ADVERTISEMENT
  About the SA Blog Network













Tetrapod Zoology

Tetrapod Zoology


Amphibians, reptiles, birds and mammals - living and extinct
Tetrapod Zoology Home

Dinosauroids revisited, revisited

The views expressed are those of the author and are not necessarily those of Scientific American.


Email   PrintPrint



Regular readers of Tet Zoo – especially those who have been following things since ver 1 of 2006 – will recognise hypothetical ‘smart dinosaurs’ as a sort of Tet Zoo meme that have been visited again, again, and again.

Much has happened since things started in 2006, and in fact I’ve since published a popular article on the subject (Naish 2008), as has Jeff Hecht (Hecht 2007). For starters, Cevdet Kosemen’s alternative smart dinosaur – the hypothetical big-brained maniraptoran Avisapiens – has become the centre of its very own alternative, speculative culture and even its own world, populated by other maniraptoran species and even by members of wholly distinct dinosaurian and non-dinosaurian lineages.

A scene from 'Dinosapien' (yeah, yeah: should really be 'Dinosapient' or such), showing Eno and Lauren (= Brittney Wilson). Yikes, so scaly! From IMDB.

Then there’s the whole 2007 BBC Horizon debacle (no, I still haven’t seen this episode) whereby Simon Conway-Morris explained how smart, humanoid dinosaurs would have been a sort of evolutionary inevitability, and might have evolved alongside humans and even co-operated with them. There’s the 2007 children’s TV series Dinosapien: it featured a big-brained dromaeosaurid called Eno and peculiar, big-brained, semi-bipedal ankylosaurs, all living in the woods of modern-day Canada. Greg Paul was involved in the design of the creatures, and I think it can be assumed that the people behind the series were very much aware of the ‘smart dinosaur’ literature. 2009 saw Richard Dawkins’s ‘coming out’ in apparent support of Russellian dinosauroids while Brian Switek, in his 2010 book Written in Stone: the Hidden Secrets of Fossils and the Story of Life on Earth, described how belief in the ‘inevitability’ of a humanoid dinosaur betrays belief in the idea “that the emergence of Homo sapiens … [is] woven into the very fabric of the universe itself” (Switek 2010, p. 268). Finally, substantial interest in the intellectual abilities of real-world maniraptorans resulted in John Marzluff and Tony Angell’s excellent 2012 book Gifts of the Crow: How Perception, Emotion, and Thought Allow Smart Birds to Behave Like Humans. I’m still reading that book and will be reviewing it here in due time. Anyway, crippled by an inability to produce anything new for Tet Zoo, I here offer this old, old Tet Zoo classic, from way, way back in 2006…

Real-world smart dinosaurs: Gifts of the Crow. I love this book.

Pretty much everyone interested in dinosaurs, in the history of life, or in such matters as the evolution of intelligence and/or brain size, will be familiar with the various speculations on ‘humanoid dinosaurs’ that have made their way into the literature. During the 1970s it became widely accepted that one group of Cretaceous theropods – the troodontids (known at the time as saurornithoidids) – were relatively big-brained, with encephalisation quotients overlapping those of modern birds and mammals. In reality, troodontids might therefore have been as ‘smart’ as bustards, emus or opossums. The notion that these dinosaurs were ‘big brained’ and therefore ‘intelligent’ seems to have given rise to a myth, however: that these were really smart dinosaurs, approaching the anthropoid level in terms of their ability to solve problems and understand the world around them. At least one book on earth mysteries and the paranormal states that some dinosaurs were “probably as intelligent as primitive man” – a quote almost certainly based on studies of troodontids. In Jurassic Park (the book), the dromaeosaurids are said to be intellectually on par with chimpanzees.

Inspired by new data on troodontid brain size, Carl Sagan speculated about intelligent dinosaurs in The Dragons of Eden (1977) and posed the question: what if non-avialan dinosaurs hadn’t become extinct? If Cretaceous forms were already so ‘smart’, what would have happened given another 60-odd million years of evolution? His question seems to have inspired a number of science fiction stories that appeared soon afterwards. Among the most important data on troodontid brain size was that published by Dale Russell, then of the National Museum of Natural Sciences (Ottawa), and besides publishing several key studies on troodontid anatomy and functional morphology, in 1982 he did a rather peculiar thing. Co-operating with taxidermist and model maker Ron Séguin, he produced the article ‘Reconstruction of the small Cretaceous theropod Stenonychosaurus inequalis and a hypothetical dinosauroid’.

While part of the article discussed how a life-sized model Stenonychosaurus (presently regarded as a junior synonym of Troodon) was reconstructed and made, the rest was devoted to a thought experiment in which Russell & Séguin (1982) reconstructed a hypothetical ‘evolved’ troodontid that had reached an encephalisation quotient similar to that of humans. Most of us are familiar with the look of the finished product, dubbed the dinosauroid, but some of the decisions Russell & Séguin (1982) made in creating the creature have not been mentioned or discussed outside of their paper.

Troodontids and other non-avialan maniraptoran theropods were fully feathered and wholly bird-like. This reconstruction, by the excellent Emily Willoughby, shows a foraging pair of the small Chinese troodontid Mei long. Used with permission.

Dinosauroid skull, from Russell & Seguin (1982). A small antorbital fenestra is still present: not entirely clear what's going on posterior to the postorbital bar, but I think that the opening there is for the ear, since they state in the text that the laterotemporal opening has become closed.

They reasoned that an enlarged brain would result in a shortened facial region, and they used the cranial proportions of a chick embryo as a guide (Russell & Séguin 1982). Based on the idea that troodontids had a reduced dentition compared to other theropods, and on the notion that big-brained primates have a reduced dentition compared to smaller-brained forms, they made the dinosauroid toothless. They further argued that a big-brained head would need to be supported directly over the body, and that a short neck and vertical human-like posture would evolve (Russell & Séguin 1982).

The vertical posture meant goodbye to the tail (reduced to a stump in the dinosauroid), and the need to give birth to big-headed babies led them to imagine a broad, human-like pelvis (Russell & Séguin 1982). Dinosauroids were imagined to be viviparous, so the model is equipped with a navel. Because human legs obviously work well for humans, Russell & Séguin (1982) proposed that human-like legs would also work for a human-like dinosauroid, and they gave the creature plantigrade feet. Interestingly, they used tree kangaroos as a model, and the feet of the dinosauroid are not tridactyl and clawed as usually shown in drawings, but four-toed, with nails rather than claws, and with the two medial toes smaller than the lateral ones.

All in all, the dinosauroid is disturbingly human-like and, I think, too human-like. While Russell & Séguin (1982) made efforts to justify their chain of logic, they may as well have looked at life restorations of hominids, and just ‘reptilised’ them a bit. Essentially the message is that the human body plan is the ‘best’ body plan for a big-brained tetrapod. But Russell & Séguin (1982) knew that they would be accused of this, and they ended their discussion by wondering if they had been directed by bias, or if the humanoid shape really would crop up convergently, as do so many other body shapes. Are they wrong, and would things have been different? Well, the last line of their article is: “We invite our colleagues to identify alternate solutions” (p. 36).

Who brought the concept of 'smart troodontids' to the mainstream? Even before Dragons of Eden and the debut of the dinosauroid, we have Adrian Desmond (in his 1975 The Hot-Blooded Dinosaurs) presenting this ugly, dragonesque troodontid as possessing "avian intelligence, stereo vision and manipulative fingers".

Understandably, the unveiling of the dinosauroid model in 1981 resulted in a huge media furore, with Dale Russell in the middle. Some people liked it, others hated it. Today it seems well-known, but I don’t think many people really understand what the point of it was. This isn’t helped by the fact that tabloid newspapers have often used images of it in stories about reptilian aliens or lizard-men, or whatever. Most amusing are those cases where the dinosauroid was completely misunderstood, as is the case in the obscure little book Dinosaur Mysteries (O’Neill 1989). Accompanying some illustrations of Dale Russell, and both Russell and Séguin’s troodontid and dinosauroid models, O’Neill’s text stated…

In 1969, a scientist named Dale Russell found some bones of a small, meat-eating dinosaur called Stenonychosaurus … This dinosaur’s skull showed that it had been small, but with a large skull. The skull also showed that Stenonychosaurus’s eyesight worked like ours. Stenonychosaurus also had hands that resembled humans’. It had thumbs that could be turned inwards to grasp things. This is unusual among animals.

Russell put together a startling model of Stenonychosaurus. He showed it standing upright, like a human. The model was 1.2 (4 ft) tall and weighed about 40 kilograms (90 lb). Russell called this human-like model a “dinosauroid”. People were amazed by this dinosaur which seemed so advanced for its time (p. 24).

John Sibbick's dinosauroid, from David Norman's 1985 Illustrated Encyclopedia of Dinosaurs.

I told all of this to Adrienne Mayor while she was researching the dinosauroid for inclusion in her The First Fossil Hunters (2000). She regarded the dinosauroid as an interesting palaeontological fiction echoing the tritons and satyrs made in ancient Greece, and noted that – like tritons and satyrs – the dinosauroid is deemed realistic enough by some for it to be misidentified as real, hence O’Neill’s mistake.

The reactions that palaeontologists have had to the dinosauroid have been mixed. Some have been fairly positive about it. David Norman (1985) considered the dinosauroid in a favourable light, concluding that “Such an idea is an obviously fanciful, though provocative thought” (p. 55). On the same page, an illustration of the dinosauroid by John Sibbick (which looks a bit scarier than the Russell and Séguin model, and also differs from it in foot anatomy) is accompanied by a caption that is even more favourable. After listing the morphological changes required to turn a Cretaceous troodontid into a dinosauroid, it ends by stating that “given the right conditions, such changes would be quite feasible”. ‘Feasible’? Note that the captions in the book were not written by Norman, so he shouldn’t get the blame for that (I will refrain from saying who did write the captions… a noted British palaeontologist with the initials MJB).

Emma Norman inside Peter Minister's dinosauroid suit, from David Norman's 1991 Dinosaur!

Another of David Norman’s books, the 1991 Dinosaur!, discusses the use of a real, live dinosauroid in the Granada television TV series that the book was written to accompany (Norman 1991). Played by a person in a suit* (obviously), the dinosauroid from Dinosaur! had a more reptilian look to it than Russell and Séguin’s model: it had far scalier-looking skin, snake-like ventral scales, and a vivid green and red colour scheme. The series concluded with the dinosauroid acting as narrator. Another positive interpretation of the dinosauroid came from Cristiano Dal Sasso (2004) in his Dinosaurs of Italy. He seems to have accepted Russell & Séguin’s (1982) idea as if it were universally agreed as likely, which it isn’t.

* 2012 UPDATE: Emma Norman was that person, and I’ve only just noticed that the suit itself was constructed by my friend Peter Minister. I’ve worked with Peter on several book projects over the past few years and had no idea he previously made dinosauroid suits.

One of my favourite pictures of the dinosauroid. It appeared online in 2008, I think at Mike Ryan's blog. The tie is decorated with Zeta Reticulans.

Other palaeontologists have been negative, however. At least one reviewer of Russell & Séguin (1982) wrote that “I do not see much value in the extremely speculative ‘dinosauroid’ discussion” (Russell 1987, p. 127). In Predatory Dinosaurs of the World, Greg Paul (1988) found the dinosauroid to be “suspiciously human”, and he argued that – were theropods to evolve big brains and ‘intelligence’ – we should instead expect them to retain horizontal bodies and long tails. Theropod expert Tom Holtz has stated much the same, and so far as I can tell from discussion, most dinosaur workers feel this way too.

There really isn’t any reason to think that big-brained dinosaurs would have evolved in the first place (recall that even ‘big-brained’ Troodon was, at best, on par with ostriches and opossums). Even if they had, there is also no reason to think that they would have ended up looking like scaly people… or feathery people, given that we now know that troodontids were feathered. On the subject of feathery troodontids, look at the excellent colour illustration of a foraging Mei long pair by Emily Willoughby, shown above, and the brooding Troodon below, by Jason Brougham. As a researcher and writer who specialises on dinosaurs, I still encounter resistance to the idea that maniraptorans like troodontids were fully feathered and bird-like. It is obvious that the people doing this resisting have somehow managed to stay several decades behind advances in human knowledge.

Troodon on its egg-filled nest, by Jason Brougham. Used with permission.

The reason that we humans have the body shape that we do is not – I think – because it’s the ‘best’ body shape for a smart, big-brained biped to have, it is instead the result of our specific lineage’s evolutionary history. Given that, so far as we know, the humanoid body shape has evolved just once, we simply have no way of knowing whether it’s a particularly ‘good’ morphology or not. Furthermore, the humanoid body shape is not a prerequisite for the evolution of big brains given that brains proportionally as big as, or bigger than, those of hominids are found in some birds and fish (that’s right: humans do NOT have the proportionally biggest brains).

Darren Naish interacts with Southern ground hornbill.

With this in mind, my feeling on dinosauroids and intelligent theropods and so on is that – if they were to evolve – they wouldn’t look like scaly, or feathery, people, but would instead be far more normal from the theropod point of view. A horizontal body posture, not a vertical one. Digitigrade feet, not plantigrade ones. A long tail, not a reduced one. The main theme here might be familiar to regular blog readers given that I’ve covered much of this before in articles on ground hornbills. While they aren’t particularly big-brained, ground hornbills can be regarded as avian pseudo-hominids, their evolution paralleling our own in several respects. The concluding paragraph of a ground hornbill article I wrote in 2006 was…

No, post-Cretaceous maniraptorans wouldn’t end up looking like scaly tridactyl plantigrade humanoids with erect tailless bodies. They would be decked out with feathers and brightly coloured skin ornaments; have nice normal horizontal bodies and digitigrade feet; long, hard, powerful jaws; stride around on the savannah kicking the shit out of little mammals; and in the evenings they would stand together in the trees, booming out a duet of du du du-du, a deep noise that would reverberate for miles around.

And here we come to the whole reason for the appearance of this post. Inspired by what I wrote I guess, the unique Cevdet Kosemen has come up with a new dinosauroid, and it is, I am pleased to say, a million miles away from scaly green humanoids. Dubbed Avisapiens saurotheos, it is of clear dinosaurian ancestry, and I like it. Thanks, Cevdet: awesome stuff!

UPDATE: if you like speculative zoology, you really might want to check out the All Yesterdays book launch, happening in London on December 7th. More on that subject here soon.

Refs – -

Hecht, J. 2007. Smartasaurus. Cosmos 15, 40-41.

Mayor, A. 2000. The First Fossil Hunters. Princeton University Press, Princeton.

Naish, D. 2008. Intelligent dinosaurs. Fortean Times 239, 52-53.

Norman, D. B. 1985. The Illustrated Encyclopedia of Dinosaurs. Salamander Books, London.

- . 1991. Dinosaur! Boxtree, London.

O’Neill, M. 1989. Dinosaur Mysteries. Hamlyn, London.

Russell, D. A. 1987. Models and paintings of North American dinosaurs. In Czerkas, S. J. & Olson, E. C. (eds) Dinosaurs Past and Present, Volume I. Natural History Museum of Los Angeles County/University of Washington Press (Seattle and Washington), pp. 114-131.

- . & Séguin, R. 1982. Reconstruction of the small Cretaceous theropod Stenonychosaurus inequalis and a hypothetical dinosauroid. Syllogeus 37, 1-43.

Switek, B. 2010. Written in Stone: the Hidden Secrets of Fossils and the Story of Life on Earth. Bellevue Literary Press, New York.

Darren Naish About the Author: Darren Naish is a science writer, technical editor and palaeozoologist (affiliated with the University of Southampton, UK). He mostly works on Cretaceous dinosaurs and pterosaurs but has an avid interest in all things tetrapod. His publications can be downloaded at darrennaish.wordpress.com. He has been blogging at Tetrapod Zoology since 2006. Check out the Tet Zoo podcast at tetzoo.com!

Nature Blog Network

Follow on Twitter @TetZoo.

The views expressed are those of the author and are not necessarily those of Scientific American.





Rights & Permissions

Comments 82 Comments

Add Comment
  1. 1. Jerzy v. 3.0. 3:07 pm 10/27/2012

    If intelligent dinosaur would have manipulative hands, it would need short fingers and flat nails. Nails serve as support of muscles in primate sensitive fingertips.

    A propos – I recently re-read Harry Harrison “West of Eden” where intelligent land-living dinosauroid Yilane descend from Tylosaurus. Never Forget!

    Link to this
  2. 2. Jerzy v. 3.0. 3:26 pm 10/27/2012

    A propos mental abilities of crow family. European Magpies pass the mirror test.

    The few animals which show self-awareness are given special protection: apes, elephants, dolphins etc. Hunting them, using in medical experiments or keeping in zoos without mental enrichment is prohibited or controversial.

    But the Magpie is viewed as just any bird. Shouldn’t it be given special legal recognition, eg. protection from killing, ban on using in experiments, special demands if kept in confinement?

    And are were ready to accept that a common suburban bird can be mentally equal to the animal celebrities like a chimpanzee and a dolphin?

    Link to this
  3. 3. naishd 3:36 pm 10/27/2012

    Certainly, most people interested in the personalities and cognitive abilities of non-human animals are more than familiar with the abilities of magpies and other corvids. Did you see the research on apparent ‘funeral rites’ in black-billed magpies?

    Darren

    Link to this
  4. 4. Andreas Johansson 4:36 pm 10/27/2012

    A little nagging thought at the back of my head: upright bipedal mammals are decidedly odd. Might we be falling in an opposite trap in assuming a hypothetical “dinosauroid” should be, more-or-less, typically theropodan overall? Maybe we should put our brains back into the box and imagine a quadrupedal, or similarly crazy, one?

    Anyway, is it only me who dislikes the term “dinosauroid”? We’re clearly not talking about a member of a family based on Dinosaurus (the dubious therapsid), nor about something that’s dinosaur-like – it’s supposed to be an actual dinosaur.

    Link to this
  5. 5. Chelydra 5:16 pm 10/27/2012

    Don’t forget about the Voth from Star Trek: Voyager, who, after evolving from Parasaurolophus, invented spaceflight during the Cretaceous and left. Very humanoid except for four-fingered, clawed hands.

    I also seem to recall a Star Trek novel where troodontids became technologically advanced while retaining a normal body plan. They had their tails surgically replaced with short counterweights to work in the tight confines of a spaceship.

    Link to this
  6. 6. naishd 5:38 pm 10/27/2012

    Comment 4; yes, the term ‘dinosauroid’ was a dumb choice. Maybe they went with it to make it seem similar to ‘humanoid’.

    Chelydra: the Voyager episode notes (if I recall correctly) that Parasaurolophus had manipulative hands, was an obligate biped etc., so I suppose the story-writer wrongly thought that ornithopods of this sort could be morphed into humanoids a la Russell & Seguin. In reality, Parasaurolophus was a heavy-bodied quadruped with short, hoofed fingers. The holograms they portray in the episode feature a synapsid of some sort as a putative Parasaurolophus ancestor.

    Darren

    Link to this
  7. 7. greg_t_laden 5:48 pm 10/27/2012

    Some random thoughts. First, in bipedalism. People outside anthro are often surprised to learn that human bipedalism does not have a satisfying explanation within anthropology, and that the link between intelligence and human bipedalism is unsupported or weak, or at least, not what is often assumed. Many species of bipedal ape existed but only one (or two, depending) experienced significant increases in brain size that we think of as “human.”

    Birds are generally bipedal, kangaroos and their relatives are generally bipedal, and lots of dinosaurs are bipedal, and there is not a general encephalization in these groups despite the presence of a few scary-smart groups of birds.

    Regarding taphonomy: There are entire categories of vertebrates that have better fossil records, and others with worse fossil records, depending on three or four factors: The habitat they tend to live in, the abundance in living communities, and the preservability of the bones. Primates are among the most diverse among living mammals but they don’t produce a great fossil record, except in the few cases where they do because of landscape related constraints (South African caves, for example). Rainforest animals are at a disadvantage. Etc. It is not unreasonable to guess that there were large categories of dinosaurs that would have been poorly reprsented in the fossil record.

    Highly intelligent human-esque dinosauroids would have reduced dentition and weak jaws, thin cranial vaults, and reduced robusticity in their post-crania, if we assume everything that is intelligent resembles an English Gentleman. If they also lived in highlands (lower preservation rates) and had a few other characteristics, why not postulate, for the purposes of science fiction, an entire race of them?

    Can’t prove it ain’t true!

    Link to this
  8. 8. Chelydra 6:07 pm 10/27/2012

    Right, I forgot about the tripedal Parasaurolophus hologram.

    Link to this
  9. 9. naishd 6:11 pm 10/27/2012

    Thanks, Greg (comment 7). If you saw the recent short article here about the ‘bonobo hypothesis’ (more specifically, the comments), you’ll know that I agree with those researchers who argue that hominid bipedality most likely evolved in an arboreal context, with compliant branches encouraging a stiff-legged gait that was then exapted for terrestrial locomotion. To get to here, hominids most likely evolved their body shape and proportions via a ‘cautious climbing’ phase (must write about that on Tet Zoo some time).

    It all means (as if it wasn’t obvious) that hominids are very different from maniraptoran theropods, the shapes and proportions of which are more linked to selection for cursoriality, raptorial use of the hands and feet, and so on.

    In view of these specialisations, it never seemed wise to imagine that maniraptorans might be on some of hominid-esque trajectory. Ok, Russell & Séguin imagined troodontids to have highly flexible, opposable manual digits (that is, they didn’t know what we know today about the birdiness of these animals) but, even so… (I can only repeat what I’ve already said above).

    Darren

    Link to this
  10. 10. Heteromeles 10:52 pm 10/27/2012

    My personal take on intelligent dinosaurs had something where instead of get rid of that oh-so-animalistic tail, they flaunted it. With feathers. And bling. They might have even looked like giant roadrunners with Archeopteryx-style bony tails, all covered with gold chain and the most tasteless medallions imaginable like a gangsta Christmas tree or a third world generalissimo.

    Seriously, why do we imagine one of these without feathers, and without all the myriad displace opportunities feathers offer? Also, considering how gaudy even simple bower birds get, why do we assume that they’re going to be so naked and boring? Every smart bird I ever met oozed attitude, and there’s no reason to think some other intelligent dinosaur descendent wouldn’t do likewise.

    Link to this
  11. 11. JoseD 11:42 pm 10/27/2012

    @Naishd

    “Then there’s the whole 2007 BBC Horizon debacle (no, I still haven’t seen this episode)”

    You can see the whole thing on Youtube ( http://www.youtube.com/watch?v=IYo44hMpl1Q&feature=plcp ). Out of curiosity, what do you think of the explanation for how humans could’ve evolved alongside non-avian dinos (about 21:40-25:30)? My favorite part is Witmer’s discussion of Troodon’s canid-esque brain power (about 30:10-34:10) although I don’t like that WWD’s Coelophysis stands in for Troodon.

    Link to this
  12. 12. Jerzy v. 3.0. 7:14 am 10/28/2012

    Are troodontids still interpreted as more intelligent than other dinosaurs? I think they were small, nocturnal hearing-heavy predators, sort of cursorial owls.

    Link to this
  13. 13. naishd 7:47 am 10/28/2012

    Jerzy (comment 12) – yes, troodontids and related maniraptorans have proportionally bigger brains than most other Mesozoic dinosaurs and were probably among the least stupid of dinosaurs. Large, sometimes asymmetrical ears suggest that they were indeed partially reliant on directional hearing, plus they have enormous orbits and seem to have done well in the cold north, living there year-round despite seasonal darkness. In other words, the cursorial owl analogy is not a bad one. I covered this at Tet Zoo ver 2 in 2007 (go here). Must revisit it here some time.

    Darren

    Link to this
  14. 14. vdinets 11:26 am 10/28/2012

    Isn’t it wrong to think that brain size is an accurate measure of intelligence when comparing taxa? I remember reading somewhere that Archosaurian brains have much higher IQ/volume rate than mammalian brains. It is totally possible that dinosaurs were smarter than birds with brains of the same size – for example, because larger parts of bird brain are used for navigation.

    I am just about to submit a paper on various coordinated hunting techniques used by crocs and gators (some of them as complex as anything used by mammals), so I am a bit skeptical about claims that dinosaurs were as stupid as ostriches.

    Link to this
  15. 15. naishd 11:39 am 10/28/2012

    Vlad – I think you’re right, there is little (maybe no) correlation between brain size and what we term ‘intelligence’. So, some small-brained animals display social skills, learning abilities and such typically interpreted as ‘intelligent’, while some big-brained animals do not perform so well. But what we know about cerebrum size in Mesozoic maniraptorans suggests that they didn’t exceed birds like ratites or chickens in ‘intelligence’.

    But, hey, I’m not saying that there’s anything wrong with being as ‘smart’ as a lizard, or a fish.

    Darren

    Link to this
  16. 16. JoseD 6:16 pm 10/28/2012

    @Naishd

    “But what we know about cerebrum size in Mesozoic maniraptorans suggests that they didn’t exceed birds like ratites or chickens in ‘intelligence’.”

    The above quote reminds me of 2 questions & a comment. Many thanks in advance for your help.

    1st question: W/all due respect, are you sure about that? I ask b/c, based on I’ve read (E.g. Page 298 of this paper: http://www.academia.edu/1139128/The_avian_brain_and_senses ), complex social behaviors such as true cooperative (as opposed to just pseudo-cooperative) hunting were w/in the cognitive capabilities of Cretaceous non-avian maniraptors (if not to the same extent as corvids & parrots). Since, AFAIK, the only non-corvid birds to be formally* described as true cooperative hunters are diurnal raptors & shrikes, wouldn’t that imply that said maniraptors (Specifically, deinonychosaurs) were similarly intelligent (especially given their similar behaviors as described in Fowler et al. 2011)?

    2nd question: I’ve read informal descriptions of ground hornbills (which are otherwise turkey-like birds behavior-wise) as true cooperative hunters (See page 229-230 of Tudge’s “The Bird”). If that’s the case, then the chicken comparison makes sense. The problem is that I haven’t been able to find any formal descriptions (Farlow 1976 might be 1, but AFAICT it doesn’t make clear whether it’s describing true cooperative or pseudo-cooperative hunting). Do you know of any formal descriptions (if not Farlow 1976) &, if so, what are they?

    My comment: This is more of a nit-pick, but I wouldn’t group ratites & chickens together when talking about avian intelligence. Based on what I’ve read, ratites are “at the bottom of the IQ index” (See “Bird IQ Index”: http://people.eku.edu/ritchisong/birdbrain.html ) while chickens “probably fall about mid-range” (See page 34 of “Keeping Chickens For Dummies”).

    *When I said “formally”, I meant “in peer-reviewed papers”.

    Link to this
  17. 17. Heteromeles 8:14 pm 10/28/2012

    Well, chickens apparently have a language of sorts, and are capable of deceiving others (Non-academic link). If we assume that chickens are mid-range for birds in general, that implies quite strongly that the majority of bird species are not only language users of some ability, but that they are capable of deception and other “primate-level” communication skills.

    I’m not sure whether Hmm or Hmmmmmmm is the proper response.

    Link to this
  18. 18. Masao 8:24 pm 10/28/2012

    So what’s this about a new book? I couldn’t find a listing at Amazon (UK or US). How can this book be ordered?

    Link to this
  19. 19. Hydrarchos 9:56 pm 10/28/2012

    Most of the “dinosauroids” in fiction tend to be based on scenarios where there was either no K/T extinction, some non-avian dinosaurs (usually – but not always, as the Star Trek example shows – theropods) escaped the K/T extinction, or occasionally in which a dinosaur civilisation’s war or ecological exploitation *caused* the K/T extinction.

    What I’d like to see, however, is a *post*-human sapient dinosaur, some millions of years in a *Life After People*-type future (a teratorn-sized corvid perhaps?). I’d imagine that corvids or parrots wouldn’t have to change their body plans much, beyond sufficient overall size to have a big enough brain, to become “human-equivalent” in civilisation-building potential. Perhaps they would be impaired relative to us in tool-use, but if they were able to stand on one leg and use their bill as the “non-dominant hand” there probably wouldn’t be many essential early-stage technologies they couldn’t manage. Maybe carrying large stones and the like would be a challenge, but they could probably figure out methods (shades of Monty Python swallows…)

    I’ve seen present-day corvids acting in ways that really looked like they have some sort of “societies”. About a year ago I walked past at least 25 magpies perched in a bare tree (in an urban area, near a school), all facing “inwards” into the tree, and agitatedly chattering at each other. As I came closer, I saw that near the top/centre of the tree was a single carrion crow, which all the magpies seemed to be looking at. It didn’t seem like they wanted to attack the crow, more like they were having an urgent discussion about information they had got from it or something. As I approached, most of the magpies flew away (but continued flying around the general area between rooves and trees, chattering loudly), while a few magpies and the crow stayed there, but fell silent. No idea what was actually going on there, but it certainly looked like some complex, and possibly inter-species, communication was happening…

    (I’d never heard of that kids’ show, and have to give it extra weirdness points for firstly having, of all things, *ankylosaurs* evolving into bipedal sapients, and secondly for having the theropod as friend to humans and the ornithopods as the villains, completely reversing the usual anthropomorphic herbivore/carnivore rule…)

    Link to this
  20. 20. vdinets 11:23 pm 10/28/2012

    JoseD: would you have the reference for cooperative hunting in shrikes, by any chance?

    Interestingly, complex (and interspecific!) cooperative hunting has been found in fishes. See:

    Bshary et al. Interspecific Communicative and Coordinated Hunting between Groupers and Giant Moray Eels in the Red Sea. PLoS Biol. 2006 December; 4(12): e431.

    For those interested, a paper just came out that neatly sorts out various levels of cooperation in hunting:

    Bailey et al. Group hunting within the Carnivora: physiological, cognitive and environmental influences on strategy and cooperation. Beh. Ecol. & Sociobiol., now available only in “online first” mode, but will probably be in December issue.

    Link to this
  21. 21. vdinets 11:26 pm 10/28/2012

    JoseD: I found the shrikes paper; thanks for bringing it to my attention.

    Link to this
  22. 22. Metridia 5:30 am 10/29/2012

    Always fun to read about Avisapiens and the others.

    About the ‘plantigrade’ dinosauroid feet. It seems like humans are rather unique amongst non-graviportal terrestrial mammals in having plantigrade feet. However, we have advanced past the completely flat-footed australopithecines to having an arched foot, which allows more efficient levering of the body against the ground as well as some level of energy recovery and shock absorbtion via the plantar fascia and the gastrocnemius/Achilles system (I think?). Meanwhile other terrestrial running mammals have become almost entirely digitigrade. I assume this is because the whole system becomes better at energy recovery or less energy expenditure when running. Given that humans are only recently terrestrial, is it possible that we were on our way to becoming digitigrade too, given the importance of running to our evolution (if you ascribe to the exhaustion-hunter hypothesis), before the technological and cultural explosion intervened? In the spirit of speculating on hominoid dinosaur evolution I wonder what we would have looked like if technology came about several million years later than it did. Would we be ostrich or Oscar Pistorius-like but with our entire legs basically a ‘blade’ designed to efficiently transmit and recover energy through a narrow contact patch with the ground?

    Link to this
  23. 23. Jerzy v. 3.0. 7:02 am 10/29/2012

    @13 Darren
    If I understand correctly what you mean by “troodontids and related maniraptorans”, troodontids were not more intelligent than dromaeosaurids and related groups.

    Which is what I expected – I was a bit dumb to talk about intelligence of all dinosaurs in general. Of course group living and omnivorous groups of dinosaurs were probably more intelligent than an average herbivore, just like modern birds and mammals differ in intelligence.

    @19 Hydrarchos
    I think there was some fantasy on a similar post-human scenario in the earlier version of Darren’s blog.

    Another interesting take is Archosaur empire at orionsarm.org , which is open-access hard sci-fi website.

    Link to this
  24. 24. Jerzy v. 3.0. 7:06 am 10/29/2012

    BTW, time to remember again a fascinating book: Bernd Heinrich’s “Mind of the Raven”. I especially liked descriptions how a flock of ravens always outsmarts a pack of wolves at the kill.

    Link to this
  25. 25. Jerzy v. 3.0. 7:08 am 10/29/2012

    BTW, am I the only one who is missing that science abandoned such big and novel topics like non-human intelligence, space quest etc., and went into increasingly fragmentary research?

    Link to this
  26. 26. Dartian 8:37 am 10/29/2012

    Jerzy:
    a flock of ravens always outsmarts a pack of wolves at the kill

    Do you consider yourself to have been ‘outsmarted’ by a mosquito every time that one bites you before you can slap it? It’s obviously much easier to ‘outsmart’ something if you can also outmaneuver it. Wonder how effective pinioned, flightless ravens would be at outsmarting wolves at the kill?

    science abandoned such big and novel topics

    Science did what when?!?

    space quest

    A politically motivated feat of engineering rather than bona fide science, really. Which started in earnest already in the goddamn 1940ies. Is that your idea of ‘novel’ research?

    Link to this
  27. 27. Dartian 9:48 am 10/29/2012

    Metridia:
    Meanwhile other terrestrial running mammals have become almost entirely digitigrade.

    But, notably, other terrestrial primates such as baboons or patas monkeys haven’t. They do adopt digitigrade (or rather, semi-digitigrade) foot postures sometimes, but, contrary to exceptions, they use these when travelling at slow speeds; when they run at faster speeds they adopt more plantigrade/palmigrade postures (Patel, 2009, 2010; Patel & Polk, 2010).

    if you ascribe to the exhaustion-hunter hypothesis

    There is very little reason to do so. We’ve been through this before in a Tet Zoo coments thread, not so long ago (look up the “Man-Eater of Mfuwe” thread).

    References:
    Patel, B.A. 2009. Not so fast: Speed effects on forelimb kinematics in cercopithecine monkeys and implications for digitigrade postures in primates. American Journal of Physical Anthropology 140, 92-112.

    Patel, B.A. 2010. The interplay between speed, kinetics, and hand postures during primate terrestrial locomotion. American Journal of Physical Anthropology 141, 222-234.

    Patel, B.A. & Polk, J.D. 2010. Distal forelimb kinematics in Erythrocebus patas and Papio anubis during walking and galloping. International Journal of Primatology 31, 191-207.

    Link to this
  28. 28. Heteromeles 10:29 am 10/29/2012

    @re: space quest. The science fiction blogs have a lot of fun getting all angsty about this. The basic problems are that (as author Charles Stross puts it) “canned monkeys don’t ship well,” and that, all too often, space exploration really is missile technology moving forward through peaceful means. In the bigger picture, we’ve found out since the 1960s that space is even more dangerous than we thought it was, and while we’ve effectively colonized space through our satellites, no one’s come up with a grand overarching reason why humans should be on other planets racking up body counts at a billion dollars (or more) per body shipped.

    On a practical basis, we still have things like the human genome race and the X-Prizes. In these guises, we still have big science galumphing forward.

    Link to this
  29. 29. JoseD 12:23 pm 10/29/2012

    @Heteromeles & Vdinets

    “I’m not sure whether Hmm or Hmmmmmmm is the proper response.”

    Given my interest level, I’d go w/Hmmmmmmm.

    “For those interested, a paper just came out that neatly sorts out various levels of cooperation in hunting:”

    That’s cool, although Ellis et al. 1993 already did that ( http://www.jstor.org/discover/10.2307/1312102?uid=3739696&uid=2&uid=4&uid=3739256&sid=21101372359457 ). If you can’t get past the paywall, the 1st 2 pages of this paper sums up the same 4 social foraging classes: http://www.ibiologia.unam.mx/links/neo/revista/Volumenes%2016-17/16-2/ON%20(16)%20271-276.pdf

    “I found the shrikes paper; thanks for bringing it to my attention.”

    No problem. Out of curiosity, which 1? I know of at least 2.

    Link to this
  30. 30. Metridia 1:52 pm 10/29/2012

    >“if you ascribe to the exhaustion-hunter hypothesis”

    >There is very little reason to do so.

    Says you. There in fact are many sound arguments in favor of it.

    Link to this
  31. 31. Metridia 1:56 pm 10/29/2012

    @Dartian:
    Additionally, humans trend towards digitigrade when running, especially if they aren’t wearing shoes.

    Link to this
  32. 32. Jerzy v. 3.0. 5:59 pm 10/29/2012

    @Dartian
    On average, wolves lose like 12% of meat to the ravens, a teensy more than human loses blood to a mosquito.

    Link to this
  33. 33. Jerzy v. 3.0. 6:05 pm 10/29/2012

    @28
    Re. poor Stross with his failed prediction of superhuman intelligence and dislike to his own primate nature. If humans don’t fly well, where is a fleet of semi-autonomous robots to build a luxury station on the orbit or Mars or atmosphere of Venus?

    I am counting on Chinese to start a competition in space and force other countries to wake up.

    Link to this
  34. 34. David Marjanović 6:24 pm 10/29/2012

    I will refrain from saying who did write the captions… a noted British palaeontologist with the initials MJB

    *facepalm*

    The man who publishes faster than his shadow!

    Says you. There in fact are many sound arguments in favor of it.

    No, dig up that post and read the comments. However, endurance running may still have been important in getting at a kill before the hyenas got there.

    The largest selection pressure towards digitigrade and unguligrade stances seems not to have been speed, but endurance: migrating over large distances is easier when you have less weight to lift, to accelerate and decelerate, at every step.

    humans trend towards digitigrade when running, especially if they aren’t wearing shoes

    At least when accelerating.

    Link to this
  35. 35. David Marjanović 6:25 pm 10/29/2012

    I am counting on Chinese to start a competition in space and force other countries to wake up.

    What for? Glory?

    Link to this
  36. 36. vdinets 6:49 pm 10/29/2012

    JoseD: Thanks again! The one I found was by Frye & Gerhardt, Apparent Cooperative Hunting in Loggerhead Shrikes. Wilson Bull., 113(4), 2001, pp. 462-464.

    Jerzy: I hope a new space race doesn’t get started. So far, manned space exploration and all probes beyond the geostationary orbit have been almost 100% useless from practical point of view. It is extremely naive to think that translocating human population to another planet could ever be easier than fixing environmental problems on our own one. I love astronomy and enjoy learning new things from Voyagers and Mars rovers, but I think it’s totally wrong to waste money on those toys while doing close to nothing to save our biosphere from falling apart within a century.

    Link to this
  37. 37. Heteromeles 8:00 pm 10/29/2012

    @Jerzy: Actually, if you think Stross stopped writing at Accelerando, you may be surprised. You might also be surprised at his take on the singularity, which was pretty skeptical to begin with, even in his books. Playing with an idea or writing a parody of it is not the same as uncritical acceptance of it.

    Certainly his blog has been a really good forum for discussing the problems of building a starship over the last few years. The general consensus is that, if you’re planning on shipping living humans to another star, we need some magic to make it work. There are problems with every aspect, from powering the starship, to keeping it from blowing up when it hits a small rock at high speed, to keeping its tiny biosphere operating without any glitches for centuries, to simply dealing with issues of birth, aging, death, and intergenerational transfer of essential skills among that small group of people. As I noted above, canned monkeys don’t ship well.

    Link to this
  38. 38. JoseD 8:13 pm 10/29/2012

    @Naishd

    Sorry to bother you again, but besides making sure that my Comment 16 questions aren’t lost amongst the raven & exhaustion-hunter discussions, I have 1 more nit-pick. In reference to the following quote, I wouldn’t group ostriches & opossums together when talking about intelligence. Based on what I’ve read (See page 25 in “Wild Mammals of North America: Biology, Management, and Conservation” AWA page 31-32 of this book: http://web.missouri.edu/~krausew/Histology/Home_files/opossum.pdf ), opossums are “above dogs and more or less on a par with pigs in intelligence”. My bad if you’ve since learned this & just forgot to update your article accordingly.

    “There really isn’t any reason to think that big-brained dinosaurs would have evolved in the first place (recall that even ‘big-brained’ Troodon was, at best, on par with ostriches and opossums).”

    Link to this
  39. 39. Metridia 9:17 pm 10/29/2012

    @David Marjanović:
    I did look at that, basically I see a couple studies, nothing conclusive. Just picking out something at random: “And here’s the important point: everything we currently know about the preferred environments of our early hominin ancestors suggests that they mostly lived in relatively mesic and well-vegetated habitats. There is no reason at all to think that they predominantly lived in sandy semidesert habitats where conditions would allow for the practising of persistence hunting. ”

    First of all, the required habitat does not have to be completely sandy; for example, the cited San running hunt took place in mixed woodland/grassland/bare soil habitat. Further, it is NOT clear that running bipedalism in humans developed in closed-canopy woodlands; for example, http://www.ncbi.nlm.nih.gov/pubmed/20534500. By no means have I looked at all the relevant citations but will try when I get a chance.

    I don’t know if every aspect of the exhaustion-hunter hypothesis will hold up under further study, and perhaps a modified form, like chasing down kills to scavenge, better explains the suite of features that make humans good endurance runners in hot weather.

    >”humans trend towards digitigrade when running, especially if they aren’t wearing shoes”

    >At least when accelerating.

    You should look up barefoot running, the optimal placement of feet is basically forefoot-first.

    Link to this
  40. 40. Mythusmage 11:45 pm 10/29/2012

    The only thing being able to recognize yourself in a mirror, is that you can recognize yourself in a mirror. What about those animals that are not visually oriented, yet are sentient?

    Does it get bored, does it socially interact, does it engage in play? If it does that then my bet is that it is sentient, even if it doesn’t recognize itself in a mirror.

    Link to this
  41. 41. Metridia 12:43 am 10/30/2012

    @naishd- I’d also like to bring it back to the original topic by posing the question another way: How ‘theropod-like’ might humans have become had we continued to transition away from arboreal ‘clambering’ bipedalism and towards cursorial bipedalism? Assuming we didn’t go down the road of the macropods…or perhaps we become satyrs :)

    Link to this
  42. 42. Dartian 5:16 am 10/30/2012

    Metridia:
    Says you.

    If you’re twelve years old, that was a good comeback. If you’re not, that was just sad.

    There in fact are many sound arguments in favor of it.

    Then by all means list them (preferably with sources to back them up). Note, however, that anything along the lines of “I really, really enjoy long-distance running myself, so I’m sure Homo erectus did too!” doesn’t qualify as an argument (never mind a sound one).

    basically I see a couple studies, nothing conclusive

    A couple studies? Just out of interest, how many studies are required to rebut and/or point out flaws in a hypothesis, in your opinion? As for conclusiveness: well, strictly speaking it’s of course very hard (impossible even!) to conclusively show that early hominids did not practise persistence hunting, so I guess you got me there. But then again, proving negatives isn’t really what science is about.

    the cited San running hunt took place in mixed woodland/grassland/bare soil habitat

    Yeah, and whenever the intended prey animals reached cover and/or were again able to run on harder soils they begun to outdistance the hunters (and sometimes ultimately succeeded in escaping them). The whole point with this specific hunting method is to get the prey exhausted before the hunters. That works best if you manage to force the prey to run on soft ground. Such as sand. (This is not to say that exhausting prey is impossible over harder ground, just that it’s much more difficult and less cost-effective.)

    it is NOT clear that running bipedalism in humans developed in closed-canopy woodlands

    Actually, the source you link to says that there may well have been riverine gallery forests (and possibly fairly extensive ones at that) in the Turkana Basin throughout the Plio-Pleistocene. So yes, there seems to have been woodland there too; surely it’s reasonable to expect that the Turkana hominids preferentially lived there rather than in the open semi-desert?

    Link to this
  43. 43. Tayo Bethel 11:06 am 10/30/2012

    Opossums on par with pigs in intelligence?

    Details details details … THat claim sounds quite incredible.

    Link to this
  44. 44. Heteromeles 11:09 am 10/30/2012

    Well, there’s this little issue that exhaustion running requires dependable sources of water. Otherwise, humans can’t sweat, and that doesn’t work. Saying that the presence of water is therefore a disproof of exhaustion running is a mistake about basic human physiology.

    Those who require total fossil proof of exhaustion running before they’ll accept it really seem like those storied anthropologists who thought that Louis Leakey was full of BS. I don’t remember their names either.

    The general utility of the exhaustion running theory is that It best explains why we’re so damn slow (we’re slower than baboons, for example–why go bipedal at all, if we’re going to hunt?), but we can run so damn far (most mammals are not marathoners, again for good reason. Jogging is not a good way to escape predators). Going bipedal decouples respiration from movement, while quadrupedal animals are stuck with breathing in rhythm with their gallop. The fact that we can adjust our breathing while jogging along allows us to run efficiently. Our style of running won’t let us get to a carcass faster than the hyenas (we *will* be the last ones on the scene), but our peculiar physiology allows us to run further with proportionally less effort. That’s how the exhaustion running trick works in any case.

    Link to this
  45. 45. vdinets 11:11 am 10/30/2012

    Why does everybody keep talking about the Sun as if they were an exact copy of the first game-hunting humans? It is true that they have many “primitive” (no racist condescending intended) features, but they certainly have plenty of cultural achievements to show. There is no reason to think that living without surface water in the Kalahari is an ancient thing; they probably didn’t move in there until the Bantu invasion. Not to mention that the Kalahari had running water relatively recently. There is no Sun rock art in the Kalahari, except in Tsodilo Hills, which are a mesic oasis. So their endurance hunts are most likely a recent adaptation, only possible in the Kalahari thanks to the unique combination of sandy soil, large open spaces and easily available (and portable!) water in the form of wild watermelons. Anywhere else in the tropics such a hunt would leave a human hunter severely dehydrated within an hour.

    Link to this
  46. 46. Henrique Niza 2:49 pm 10/30/2012

    “There really isn’t any reason to think that big-brained dinosaurs would have evolved in the first place.”

    There already are, they’re called corvids. ;)

    Link to this
  47. 47. Heteromeles 5:08 pm 10/30/2012

    Actually, I first encountered endurance running in Heinrich’s Born to Run, where he talks about how at least one Navajo hunter runs down and strangles deer in Arizona, so as to obtain the unpunctured hides they need for certain rituals. I don’t know how one skins a deer without cutting. I guess that’s a different ritual.

    Anyway, it’s not limited to the San people by any stretch of the imagination. The basic point about marathon hunting is that it’s tedious. It’s also unsuitable for a variety of animals like, oh, rabbits and fish. That was less of a problem back in the Pleistocene, of course, when there was rather more land to hunt on, and rather more animals to hunt.

    The counter-argument that I notice no one is attempting here is explaining why humans seem so well built for long-distance jogging, if it isn’t (or wasn’t) adaptive. endurance running is not a trait of any other striding biped, to my knowledge. For example, we don’t see roadrunners or ground hornbills running 20 miles at a time.

    Link to this
  48. 48. vdinets 6:09 pm 10/30/2012

    I happen to know a few Navajos who live on their main reservation on New Mexico/Arizona border, and talked to them last spring about the book. None of them had ever heard that it’s possible to run down a deer. The way deer are caught on foot is by following their tracks for many days without any running – that leaves them insufficient time to rest and feed. But the Navajos could only do it when there was snow on the ground – an option not available for most Africans. In Korea they used to do this in summer, but on soft soil of broadleaf temperate forests, and it required the level of tracking skill very few people could attain. Even if Heinrich’s account is true, which I now doubt, it was probably practiced in winter only. Note that the Tarahumara also do most of their running in winter, when it is bitterly cold in the Sierra Occidental.

    I don’t see any particularly good adaptations to endurance running in humans. Dogs can run and pull a sled at 16-20 mph for 16 hours a day every day. Wolves routinely jog for 40-60 km a day all winter. Male tigers can travel 70 km per day on average year after year. Hyenas cover 50-70 km every night. African wild dogs spend, on average, 14 hrs a day running, most of it in daytime. Even a well-trained human is well behind in terms of endurance. Remember, you have to be able to hunt day after day to be a reliable provider.

    I think what we are really adapted for (compared to other primates) is walking for 10-20 km per day while carrying stuff (babies, skins to keep us warm at night, fire in mud-covered baskets, hunting gear) in our hands. (Carrying things on top of the head seems to be a more recent African invention, since neither people of Khoisan race nor any out-of-Africa people practice it that much).

    Link to this
  49. 49. David Marjanović 6:22 pm 10/30/2012

    I love astronomy and enjoy learning new things from Voyagers and Mars rovers, but I think it’s totally wrong to waste money on those toys while doing close to nothing to save our biosphere from falling apart within a century.

    I completely refuse to accept the money argument, however. Hundreds of billions of $ are being wasted on military budgets; in comparison, everything else is peanuts. Funding both space exploration, even putting people on Mars, and saving the biosphere could easily be done at the same time; it’s a question of political will, not of money.

    >”humans trend towards digitigrade when running, especially if they aren’t wearing shoes”

    >At least when accelerating.

    You should look up barefoot running, the optimal placement of feet is basically forefoot-first.

    I’ve done a lot of running in sandals and in shoes with thin, hard soles, in which it hurts to put the heel on the ground first, on tarmac. I can sustain digitigrady for quite some time, but not for very long…

    why go bipedal at all, if we’re going to hunt?

    This question is wrong. Unlike baboons and patas monkeys, we were already bipedal before we came down to the ground, and we came down to the ground before we were able to run.

    Nothing in biology makes sense except in the light of evolution (Th. Dobzhansky 1973); nothing in evolution makes sense without a phylogeny (G. C. Gould & B. MacFadden 2002, 2004).

    Link to this
  50. 50. David Marjanović 6:26 pm 10/30/2012

    I think what we are really adapted for (compared to other primates) is walking for 10-20 km per day while carrying stuff (babies, skins to keep us warm at night, fire in mud-covered baskets, hunting gear) in our hands.

    I agree.

    Link to this
  51. 51. Jerzy v. 3.0. 6:40 pm 10/30/2012

    I also agree that human long-distance running is a by-poduct of long-distance walking for foraging.

    Also, please remember that at least Homo habilis already threw stones as projectiles and ate big mammals. So if there was time in evolution when humans hunted big animals by exhausting them in absence of tools, it was when hominids were much smaller and differently built than modern marathoners.

    And exhaustion hunting requires a rare reliable soft surface for tracks to show, plus tracking skills and capacity to carry water. I know of no proof (and it doesn’t seem very likely) that humans evolved tracking skills and water containers before hunting tools.

    Link to this
  52. 52. vdinets 6:52 pm 10/30/2012

    David: I assure you that if I was responsible for structuring the US budget, there would be HUGE defense cuts. Unfortunately (for the planet), I’ve been born outside the US and can’t run for president, so it’s unlikely that a major re-locating of funds from MIC to something useful would happen anytime soon :-(

    Link to this
  53. 53. Jerzy v. 3.0. 7:03 pm 10/30/2012

    @36
    Didn’t you see Avatar? What can be better for a biologist than discovering a whole new ecosphere? And currently there may well be life in several places in our Solar System, but humanity is lagging to check it.

    @37
    Before worrying about shipping humans to other stars, I would like to see intensive exploration and colonies of Venus and Mars, please.

    I also believe that within few decades (if not years) computer programs will become sufficiently advanced to semi-autonomously finely manage space station, or mine raw metals from the Moon or Mars build a space station locally.

    This is a scenario when humans send just several lightweight robots with few supplies, but complex instructions and communication channel. Robots then build everything (beginning with mines and followed by more robots) and humans fly in only when everything is ready, painted, checked, and greeting cards are put in bedrooms.

    Stross and many other authors are inconsequential, if you think about it. They imagine artificial intelligence with cognitive skills above human, but things like building and repair of spaceships must still be done on Earth by humans or eventually, those super-intelligences.

    Probably off topic, but surely it is fun!

    Link to this
  54. 54. David Marjanović 7:11 pm 10/30/2012

    David: I assure you that if I was responsible for structuring the US budget, there would be HUGE defense cuts.

    Oh, it’s not just the US. The US is of course the extreme example; but did you know Greece has a ridiculously large defense budget, that this is apparently a large part of the reason for its financial crisis*, and that it has lots and lots of tanks that couldn’t even be used in that mountaineous country? They wouldn’t even help against the Turkish arch-enemies and NATO partners!

    * “Crisis” by ECB measures. The US, for example, is deeper in debt, but nobody makes it feel guilty for that…

    Didn’t you see Avatar? What can be better for a biologist than discovering a whole new ecosphere? And currently there may well be life in several places in our Solar System, but humanity is lagging to check it.

    And you propose going there in person as the method for checking it?

    Seriously?

    Link to this
  55. 55. Halbred 7:52 pm 10/30/2012

    @vdinets Even if you could run for President, any hint of shrinking the defense budget would effectively end your campaign. Half the country would crucify you (politically). This is disappointing for many reasons.

    Link to this
  56. 56. JoseD 8:40 pm 10/30/2012

    @Tayo Bethel

    Hunsaker & Shupe 1977 is the source cited on page 25 of “Wild Mammals of North America: Biology, Management, and Conservation”. Page 31-32 of this book informally describes the intelligence tests taken.

    @Naishd

    No more questions or nit-picks for now (although I am looking forward to your response to Comment 16), just comments on things I missed.

    “After listing the morphological changes required to turn a Cretaceous troodontid into a dinosauroid, it ends by stating that “given the right conditions, such changes would be quite feasible”.”

    I have that book & there are a lot of similarly weird captions (E.g. “Although the general consensus now is that hadrosaurids were not primarily aquatic animals, their characteristic deep tails and paddle-like hands are evidence that they were certainly capable of swimming. It is possible that when threatened by a tyrannosaurid predator they would retreat to the safety of deep water just as these Parasaurolophus are doing with some alacrity.”). I can’t help but wonder what the heck MJB was thinking when he wrote them.

    “Furthermore, the humanoid body shape is not a prerequisite for the evolution of big brains given that brains proportionally as big as, or bigger than, those of hominids are found in some birds and fish”

    & mammals (“The brain of the Etruscan shrew weighs just 0.1 g (0.0035 oz.), yet relative to its tiny body, its brain is bigger than ours”) from here.

    Link to this
  57. 57. vdinets 8:59 pm 10/30/2012

    Jerzy: I’d love to explore another biosphere (if there is such a thing, which is by no means certain), but I don’t think we’ll ever find one. I am sure that if extraterrestrial life does exist, it is very rare. Most people don’t realize how many conditions must be exactly right for a biosphere to develop.

    David: true, but the US is the one with the largest budget.

    Halbred: there wouldn’t be a single word of truth in my campaign. Truth only hurts your ratings. Just look at Romney: he lies in every sentence, and keeps advancing in polls.

    Link to this
  58. 58. trolleyfan 11:12 pm 10/30/2012

    I suspect the “dinosauroid” owes more to “Land of the Losts’s” Sleestakx than anything else. (http://landofthelost.wikia.com/wiki/Sleestak)

    Link to this
  59. 59. Metridia 11:45 pm 10/30/2012

    “If you’re twelve years old, that was a good comeback. If you’re not, that was just sad.”

    Actually, it was entirely appropriate to your Dwight Schrute-like dismissal of what I said, and referencing a comment section that cites a few *inconclusive* studies. As in, the comments you made in the other thread didn’t rule out the endurance running hypothesis nor does it make it exceedingly unlikely.

    “Actually, the source you link to says that there may well have been riverine gallery forests (and possibly fairly extensive ones at that) in the Turkana Basin throughout the Plio-Pleistocene. So yes, there seems to have been woodland there too; surely it’s reasonable to expect that the Turkana hominids preferentially lived there rather than in the open semi-desert?”

    The paper says: “for example, modern Kenyan savanna environments like Nakuru, Maasai Mara, or Amboseli are not particularly good analogs for Turkana Basin paleoenvironments, because their temperatures are far lower (MAT = 17, 19, and 25 °C, respectively) than those inferred here (~ ≥30 °C). If past environments were more vegetated, a more suitable analog may be the grassland–bush–gallery forest environment typical of the lower Omo River valley north of Lake Turkana. ”

    NOT closed-canopy forest. Here are some pictures of this type of environment: link link link link.

    To me, that looks rather like the ground over which the San were hunting in the BBC video. Open ground with which to see footprints. So it’s possible.
    Further, the dense forests are really mostly along the river. There’s no reason that early hominids would have restricted themselves to a band of woods a hundred feet wide next to the rivers.

    In response to others’ points, it does seem like exhaustion hunting might require water carrying, which is a relatively advanced technique. Given how hot and dry these environments were, perhaps merely being active during the day, walking and running across the landscape, is enough for humans to develop such comprehensive cooling adaptation. The question is then what niche did they exploit that required daytime activity, and why did humans end up with an odd walking/jogging optimal gait.

    Another valid criticism is the advanced cognition required to track by footprints only. Also, would humans pass out from heat stroke or thirst before they would be able to catch up to an animal less well adapted to heat dissipation than humans? Thus, it seems that early humans would need to be able to maintain visual contact, and to chase their prey to heat stroke in the space of a relatively short period. Perhaps this isn’t possible, perhaps it would only work on a few prey types.

    “Also, please remember that at least Homo habilis already threw stones as projectiles and ate big mammals. So if there was time in evolution when humans hunted big animals by exhausting them in absence of tools, it was when hominids were much smaller and differently built than modern marathoners.”

    It doesn’t have to be in absence of tools- perhaps you chase/track the prey down until they are within throwing distance, with their flight instinct weakened with fatigue.

    “I’ve done a lot of running in sandals and in shoes with thin, hard soles, in which it hurts to put the heel on the ground first, on tarmac. I can sustain digitigrady for quite some time, but not for very long…”

    Yes, you have to train yourself to run properly when running barefoot. It’s not something that happens automatically. It requires development of muscles and muscle memory, as well as a strong foot arch to help absorb shock.

    “Even a well-trained human is well behind in terms of endurance. ”
    Didn’t the Tarahumara run over hundreds of km over days to communicate between villages? Further, you are missing that the advantage humans supposedly had was heat dissipation. Again, who collapses first, the prey or the humans? Not saying it isn’t a dangerous hunting technique…

    “The general utility of the exhaustion running theory is that It best explains why we’re so damn slow (we’re slower than baboons, for example–why go bipedal at all, if we’re going to hunt?), but we can run so damn far (most mammals are not marathoners, again for good reason. Jogging is not a good way to escape predators). Going bipedal decouples respiration from movement, while quadrupedal animals are stuck with breathing in rhythm with their gallop. The fact that we can adjust our breathing while jogging along allows us to run efficiently. Our style of running won’t let us get to a carcass faster than the hyenas (we *will* be the last ones on the scene), but our peculiar physiology allows us to run further with proportionally less effort. That’s how the exhaustion running trick works in any case.”

    I also like this idea. Once we get to carcasses, we may actually have been able to intimidate other animals away, because we could strike from a distance by throwing rocks. Although even more recent archaic hominids, like H. neanderthalensis, didn’t have a fully modern overhand-throwing ability and instead relied more on stabbing, based on the structure of the shoulder. So was early hominid throwing deadly enough to complement our endurance-running skills to make kill-usurping a dominant human foraging tactic, sufficient to explain the aforementioned physiological adaptations?

    Also, was the energy expended running to a kill still easier than finding and killing prey ourselves? Perhaps in the days before spear-throwing, yes.

    Link to this
  60. 60. Heteromeles 12:26 am 10/31/2012

    @vdinets: Bernd Heinrich, Why We Run, p. 128-129:

    “I consulted my friend the folklorist Barre Toelken at Utah State University (who had lived with and married into the Navajo tribe during the 1950s) trying to find out if the practice of running down deers and antelopes, in the days before long-range killing by rifles, might be referred to in folklore.
    ‘”I saw it done in the 1950s,” he wrote me.
    ‘But it’s deer rather than pronghorns. What I saw was my friend Yellowman (in the 1950s he was about forty or forty-five) jogging along on the trail of a deer in semi-open desert country. The deer runs in bursts and then stops, listens, and then sprints again. The hunter, by consistently jogging along the trail left by the animal, eventually tires it out. Then, approaching the exhausted deer, he slowly puts an arm-lock on it and holds his hand over the mouth and nose of the deer, smothering it. His hand is supposed to have corn-pollen in it, which is considered sacred. The deer dies while breathing the sacred substance, and then its hide can be used as a sacred deer hide, unblemished because it’s from an animal who was not punctured when it was killed. I never heard of the Paiutes doing it, but I know very little about them. I don’t personally know of anyone who still does it, but there must be some people, since sacred hides are still in demand for ceremonies, and they’re still obtainable. It usually took Yellowman all afternoon to run down the deer.”

    Also check Peter Nabokov’s Indian Running Amazon Link, which apparently contains information on similar hunting techniques from other tribes.

    Hopefully, armed with this information, you can go back to your Navajo contacts and see if they know anything and are willing to talk about it.

    As for Homo habilis throwing stones, the most complete skeleton listed by Wikipedia (OH 62 and KNM-ER3735) lacks much evidence of a shoulder joint (link), and the analysis appears to suggest that H. habilis shoulders “retained much of the presumed ancestral condition in its shoulder morphology” (Susan Larson, The First Humans: Origin and Early Evolution of the Genus Homo, 2009).

    Therefore, I’d suggest that assertions that Homo habilis hunted using missile weapons is on far shakier ground than assertions that humans hunted by running prey to exhaustion.

    Link to this
  61. 61. Margaret Pye 12:43 am 10/31/2012

    Why would a sapient crow or parrot need to be unusually large or flightless? Wild speculation here, obviously, but it strikes me that you could get a perfectly plausible (if alien) parrot or crow civilisation by evolving slightly higher intelligence and keeping the rest of the body exactly the same.

    I don’t buy the argument that “they’re too small to have complex enough brains”. It seems to me that a bauplan that can support a brain capable of “This unfamiliar wire stuff is bendy! Let me see if I can make a harpoon by bending it!”, should be able to support a brain capable of civilisation. A human has, what is it again, two or three times the brain volume of a chimpanzee? I know it’s not much more. That’s not much added weight, and not much added metabolic load. I suppose the necessary skull restructuring might cause problems with a parrot’s jaw strength.

    Link to this
  62. 62. Heteromeles 1:04 am 10/31/2012

    Ah, finally found my copy of Christopher McDougall’s Born to Run. Here’s his summary of Dennis Bramble and David Carrier’s case for humans adapted to running.

    Comparison of a chimp (our nearest relative, and a walker) and humans:
    –Chimp: long splayed toes, Human: short in-line toes
    –Chimps: Achilles tendon (connected to heel) absent. Humans: Achilles tendon present
    –Chimp: foot flat. Humans: foot arched
    –Chimp: small gluteus maximus. Humans: large gluteus maximus
    –Chimp: no nuchal ligment (behind the head). Humans: nuchal ligment.

    Other animals that share most or all of the traits of humans include dogs and horses, both of which are runners. Attachments for the Achilles tendon and Nuchal ligament are present in Homo erectus and absent in Australopithecus. The Achilles tendon, incidentally, isn’t needed for bipedal walking, but it serves as a spring, making running more efficient, rather than faster. The nuchal ligament and other structures in our neck work with our swinging arms to keep us from swaying and twisting in midstride.

    Additionally, when quadruped mammals run, they are constrained to one breath per step, due to the flexing of the spine and rib-cage powering the lungs. Humans, who do not use their spines to run, typically average two breaths per running step, although it varies substantially.

    Finally, humans are among the few animals that shed most of our heat by sweating. There are suggestions that being vertical also exposes less of our bodies to insolation, but humans don’t always hunt at noon, so I discount this.

    According to the book, videos of runners on treadmills show that the average human has a longer stride than a horse. Also, human joggers in decent shape run at 3-4 meters per second, about the same speed as a deer trots. However, if a deer breaks 4 meters per second to get away from a human jogger, it has to start galloping, where it gets stuck with one breath per stride and is thus distance-limited. A horse can hold a 7.7 meter/sec gallop for at most ten minutes before it has to slow to 5 meters/second or slower, while a fit human can run at 6 meters/second for up to six hours.

    Finally, based on data from the NY City Marathon, starting at age 19, marathoners increase in speed until age27, then speeds decline. However, the decline is very slow: 64 year-olds run as fast as 19 year-olds. A sixty year-old can apparently beat someone one-third his age, if they are both in shape and they are otherwise equal. It’s unclear whether there’s any other sport where old people can beat youngsters, and it suggests that human adults are adapted to long-distance running.

    That’s the case for humans as runners.

    Link to this
  63. 63. vdinets 2:54 am 10/31/2012

    Well, I don’t know anatomy well enough to tell which of these adaptations are needed only for long-distance running and which ones are also useful for long-distance walking or short-distance running. But I strongly suspect that changes in neck anatomy have something to do with higher center of gravity in human head compared to ape heads, and with much longer necks in humans.

    One breath per stride is not necessarily a bad thing: it is perfectly enough if you have sufficient lung volume, and it allows you to use striding movement for breathing without much additional effort required to move the ribcage. Proponents of endurance hunting theory keep saying that human way of sweating is beneficial, but in reality it creates such a dependence on water supply that any extensive physical activity away from water sources becomes impossible in tropical climate.

    Those speeds for horses and humans don’t make any sense. A horse can easily canter for hours at 20 kph; galloping speed is around 40-50 kph (depending on breed). Most savannah ungulates have somewhat similar speeds; deer are irrelevant because they are forest animals and don’t live in Africa. Human running speed at long distance is seldom more than 12 kph. The Mongols didn’t use horses because they were too lazy to walk; they did so because horses provided incomparably better speed and mobility.

    Data from NYC marathon is pretty much irrelevant. Stone Age humans seldom even survived to 64, and you have to be in really good health to run long-distance.

    Link to this
  64. 64. Dartian 3:42 am 10/31/2012

    #27:
    contrary to exceptions

    Stupid typo that I only now noticed; it should of course be “contrary to expectations“.

    Heteromeles:
    exhaustion running requires dependable sources of water. Otherwise, humans can’t sweat, and that doesn’t work. Saying that the presence of water is therefore a disproof of exhaustion running is a mistake about basic human physiology.

    That’s not quite it. The presence of water is of significance because it usually also implies the presence of trees and forests/woodlands. And in forest habitats there are more cover and more potential hiding places for the prey animals. (And, conversely, fewer places for the human hunters to set up snares and traps, or an ambush.) This is why successful persistence hunting requires fairly open terrain, where you can see your intended quarry from a long distance away and more easily anticipate its movements.

    64 year-olds run as fast as 19 year-olds. A sixty year-old can apparently beat someone one-third his age, if they are both in shape and they are otherwise equal.

    Has anyone over 50 years (or even anyone over 40 years) ever actually won an Olympics or a World Championships medal in marathon?

    It’s unclear whether there’s any other sport where old people can beat youngsters

    Isn’t that generally true for basically any sport that requires more technical skill than mere brute strength and speed? How about archery, for example? (Admittedly, archery is a relatively recent innovation in human evolutionary history, but it’s been around for several thousand years.) Or how about discus and javelin throw (just to stick to ‘hunting-like’ sports)?

    Vladimir:
    Proponents of endurance hunting theory keep saying that human way of sweating is beneficial, but in reality it creates such a dependence on water supply that any extensive physical activity away from water sources becomes impossible in tropical climate.

    Good point.

    Link to this
  65. 65. Dartian 9:33 am 10/31/2012

    Metridia:
    *inconclusive* studies

    Why do you keep using the word “(in)conclusive” in this discussion? We are talking here about a hypothetical, unobservable behaviour pattern of extinct organisms! Just what the hell could anyone say conclusively (as in, with absolute certainty) about it? For the record, I have never said that early hominids did not – or could not – ever practise persistence hunting; I have just pointed out reasons (based on what we do know about modern-day mammals and hunter-gatherer societies) why it seems unlikely that they hunted in that way on a regular basis (or, to be more precise, on so regular a basis that it has actually affected the ecomorphology and -physiology of our entire species).

    What we can be reasonably certain about is that persistence hunting is an extremely costly and, perhaps even more importantly, in most environments an unnecessary method of hunting. In most habitats, there are usually much easier ways of catching your meal than running after it for hours and hours.

    the comments you made in the other thread didn’t rule out the endurance running hypothesis nor does it make it exceedingly unlikely

    See above. I don’t consider the idea of early hominin endurance running impossible, just unparsimonious.

    NOT closed-canopy forest

    Please do not mis-quote me. I intentionally used the terms “gallery forests” (which is an exact term used in that paper by Passey et al., on page 11247) and “woodland”, respectively. Such vegetation types may or may not be “closed-canopy forests”; I took no stand on that issue.

    There’s no reason that early hominids would have restricted themselves to a band of woods a hundred feet wide next to the rivers.

    Why not? Modern-day chimpanzees do exactly that in some places, such as the Hoima District in Uganda (McLennan, 2008). And before you protest that chimpanzees are not comparable to early hominins, let me stress that my point is that the Hoima chimpanzee example illustrates the fact that populations of large-bodied primates can indeed live, or at least survive* for a considerable length of time, in such seemingly sub-optimal habitats. (Incidentally, these chimps frequently venture out to the neighbouring savanna – where they are sometimes preyed upon by lions! – in order to reach isolated fruit-bearing trees.)

    * The Hoima chimpanzee population is today threatened with extinction, but this threat comes from human activity (including active persecution) rather than from their habitat being intrinsically unsuitable to them.

    Reference:
    McLennan, M.R. 2008. Beleaguered chimpanzees in the agricultural district of Hoima, Western Uganda. Primate Conservation 23, 45-54.

    Link to this
  66. 66. naishd 11:12 am 10/31/2012

    Much enjoying the discussion you’re all having – too busy to find time to contribute. Just want to note here that several comments – locked up in moderation due to the links they included – have been added upstream of this one.

    Darren

    Link to this
  67. 67. David Marjanović 1:07 pm 10/31/2012

    Chimps throw stuff at attacking leopards, right? How do they do it? Why wouldn’t an animal capable of brachiation be capable of throwing overhead?

    Halbred: there wouldn’t be a single word of truth in my campaign. Truth only hurts your ratings. Just look at Romney: he lies in every sentence, and keeps advancing in polls.

    It’s not quite clear if his advance petered out before Sandy blew it away… but it has stopped in any case.

    The question is then what niche did they exploit that required daytime activity

    …er. Anthropoids are ancestrally diurnal. No explanation is required for the retention of a plesiomorphy.

    Why would a sapient crow or parrot need to be unusually large or flightless? Wild speculation here, obviously, but it strikes me that you could get a perfectly plausible (if alien) parrot or crow civilisation by evolving slightly higher intelligence and keeping the rest of the body exactly the same.

    Agreed. Gray parrots can be taught to read…

    I suppose the necessary skull restructuring might cause problems with a parrot’s jaw strength.

    It didn’t with ours – and, compared to chimps, we’re outright durophagous.

    –Chimps: Achilles tendon (connected to heel) absent. Humans: Achilles tendon present

    …Are you trying to say the gastrocnemius muscle reaches all the way to the heel in chimps, without an intervening tendon? That’s said to be the case, or nearly so, in human couch potatoes; in people who run a lot, the muscle shortens and the tendon lengthens.

    –Chimp: small gluteus maximus. Humans: large gluteus maximus

    Is that even genetic? I’m told it balloons if you run a lot.

    –Chimp: no nuchal lig[a]ment (behind the head). Humans: nuchal lig[a]ment.

    That’s the exact opposite of what I’d expect. Nuchal ligaments are widespread, perhaps universal, in tetrapods; they’re especially well developed in quadrupedal mammals with heavy heads. I’d expect knuckle-walking chimps to have much larger nuchal ligaments than bipedal humans.

    a fit human can run at 6 meters/second for up to six hours

    Wwwwwwwwait.

    1 m/s = 3.6 km/h. 6 m/s = 21.6 km/h. Running at that speed for 6 h will get you far: more than 120 km. A human running 120 km nonstop? Was “6″ a typo? If not, I have to ask the old question: “What have you smoked, and can I get it legally in the Netherlands?”

    I’ve heard of double marathons (more than 84 km). That’s the kind of distance where the women catch up with the men because fat storage becomes at least as important as low total weight and high muscle mass. But 120 km? In 6 h nonstop? No.

    Link to this
  68. 68. vdinets 1:47 pm 10/31/2012

    Wow, that Born to Run book is apparently as scientific as Ungulate Taxonomy! I’m glad I didn’t waste my time reading it ;-)

    Link to this
  69. 69. Margaret Pye 9:18 pm 10/31/2012

    /I suppose the necessary skull restructuring might cause problems with a parrot’s jaw strength.

    It didn’t with ours – and, compared to chimps, we’re outright durophagous./

    Really? I’d picked up the impression (don’t know where from, though) that humans have much weaker jaws than chimpanzees. Have I been relying on outdated information?

    I wonder how much jaw strength a Stone Age parrot would really need? Probably similar to a regular parrot, since they’d be using the beak as their primary manipulator.

    How’s that for an idea more fun than green scaly lizard men? Australian cockatoos gnawing high-rise tribal settlements out of big gum trees… Arctic ravens harrying reindeer, setting fires to frighten them over cliffs… it’d be really interesting to view the world from the perspective of an animal so much smaller, and so much more vulnerable to predation.

    Link to this
  70. 70. Dartian 3:16 am 11/1/2012

    David:
    Nuchal ligaments are widespread, perhaps universal, in tetrapods; they’re especially well developed in quadrupedal mammals with heavy heads.

    And yet the striped hyena Hyaena hyaena, for example, apparently lacks the nuchal ligament (Spoor & Badoux, 1986). The supposed link between the presence of nuchal ligaments and (endurance) running capabilities seems to be anything but clear.

    Reference:
    Spoor, C.F. & Badoux, D.M. 1986. Descriptive and functional myology of the neck and forelimb of the striped hyena (Hyaena hyaena, L. 1758). Anatomischer Anzeiger 161, 375-387.

    Link to this
  71. 71. farandfew 7:18 am 11/1/2012

    Anyway, even if all those supposed running adaptations in humans vs chimps are bona fide, what’s stopping them being adaptations to running away from stuff – because climbing trees is no longer the best option?

    Just to get back to the original subject for a moment – I feel it would be more fun to speculate on how the intelligence of an intelligent dinosaur might differ from our own, rather than just its bauplan. Of course that is vastly more speculative than something which is already hugely speculative but I wonder if anyone knows of any interesting speculations in that direction.

    Link to this
  72. 72. Jerzy v. 3.0. 8:36 am 11/1/2012

    @Heteromeles
    On top – what deer? If you are talking about American white-tailed deer, this is rather specialzed saltatorial species, that is one preferring to run into cover and hide, not adapted for long escapes. Whitetail it main game of modern North American hunters, after extiction of megafauna, bison etc, but it doesn’t occur in Africa.

    Then – in African ungulates, saltatorial running is by no means universal adaptation.

    Nor there is any direct record that primitive hominids selectively or commonly hunted small saltatorial ungulates.

    Link to this
  73. 73. Heteromeles 10:30 am 11/1/2012

    @Jerzy: I’m assuming he was hunting black-tailed/mule deer, because they’re more common in the west. There is a white-tailed deer in Arizona, but it doesn’t appear to live on the Navajo reservation.

    Link to this
  74. 74. Heteromeles 12:37 pm 11/2/2012

    That’s what’s in Born to Run, copied verbatim, and since McDougall (the author) doesn’t list a bibliography, I didn’t chase it back. My impression was that he got those information sitting down with the scientists. I’m not going to assign blame for anything other than failure to back up that book with a bibliography. So far as I know, David Carrier at least is a reputable scientist. Anyone here want to smear his reputation, while you’re bloviating?

    On the other hand, McDougall did run a 50 km race, in the mountains, with some of the best ultramarathoners of the time and some Tarahumara Indians. Based on running experience, he knows more than anyone here.

    Similarly, Bernd Heinrich set the American record in a 100 km ultramarathon at the age of 41, and wrote Why We Run about how he used his physiology expertise and research to train for the race. As a side note, at 39, he’d missed qualifying for the US olympic team by 20 seconds. Based on demonstrated expertise (both running and in academia), I tend to believe him when he says that humans evolved for long-distance running.

    Getting back to other proposed reasons for humans to run. Yes, getting away from predators. Right. In general, humans are lousy at running away from quadrupedal predators over short distances, as documented in folklore, numerous fatalities, movies, playing games with pet dogs, and so forth.

    The problem is that humans are demonstrably good at running long distances fairly slowly, as opposed to short distances quickly, and this ability demonstrably degrades slowly with age (cf: Heinrich, above). That sure sounds adaptive to me.

    As for throwing, it’s harder to tell. There have been a number of old baseballers (Wikipedia ref), so one could argue that the evidence also supports human adaptations for throwing. The problem is that modern human shoulders only seem to go back to Homo erectus (see previous entries for references). Chimps throw stuff, for short distances and inaccurately, and their best throws compare very poorly with, say, that of a human baseball player, even though they are proportionally much stronger and have longer arms.

    As for which came first, the Laetoli prints at 3.6 million years old show that arched feet with developed heels pre-date the modern shoulder, although shoulder material from Homo habilis appears to be pretty minimal. Based on this, I think we can dismiss the idea that humans evolved to throw stuff first, and then became long-distance runners.

    Link to this
  75. 75. Jerzy v. 3.0. 5:00 pm 11/2/2012

    @Heteromeles
    Mule deer is similar to white-tail in saltatorial escape.

    About throwing – baboons and chimps can also throw things with fair accuracy. On the other hand, 1,8m years ago Homo erectus already produced weapons designed to kill large animals. So there was a plenty of time for this supposed endurance running to dis-evolve.

    I guess Mr McDougall was not familiar with the chronology of human evolution? Much like vegetarians, who think that humans are not adapted to eating meat.

    Link to this
  76. 76. vdinets 5:16 pm 11/2/2012

    Putting obviously fake data into a book is scientific fraud and should be called out, no matter how respectable the author is or how successful his career has been. I think we’ve already discussed this. Even the most respectable scientists tend to get carried away when pushing their pet theories.

    Individual ability to be a good long-distance runner doesn’t make one qualified to theorize about human evolution. To the contrary, the fact that such achievements are so rare is a strong argument against the theory.

    Humans might be bad at running away from predators, but it doesn’t mean there wasn’t a strong selective pressure to make them better. When you are running away from a lion, you are not competing with the lion – you are competing with the rest of your tribe, because it’s the slowest runner who gets caught.

    Link to this
  77. 77. David Marjanović 8:40 pm 11/3/2012

    Really? I’d picked up the impression (don’t know where from, though) that humans have much weaker jaws than chimpanzees. Have I been relying on outdated information?

    AFAIK, they have low measured bite forces, and we have pretty high ones. In any case, we have much thicker enamel, and our premolars look like molars, not like canines.

    I wonder how much jaw strength a Stone Age parrot would really need?

    Same as today.

    So far as I know, David Carrier at least is a reputable scientist. Anyone here want to smear his reputation, while you’re bloviating?

    Wrong question.

    Right questions:
    1) What do the data say?
    2) Have you no shame to use an argument from authority?

    Based on demonstrated expertise (both running and in academia), I tend to believe him when he says that humans evolved for long-distance running.

    Another argument from authority. Still no evidence that humans can run 120 km in 6 h (or at all); still no evidence for natural selection for this ability.

    Link to this
  78. 78. Dartian 1:53 pm 11/4/2012

    Heteromeles:
    Based on running experience, he knows more than anyone here.

    A general remark: be careful with making assumptions of that kind about the people who post comments here on Tet Zoo. You do not know what kind of experience they/we may have in various fields. Just sayin’.

    humans are demonstrably good at running long distances fairly slowly [...] That sure sounds adaptive to me

    When it’s put like that, the entire premise of this idea sounds just odd. Should we really consider ourselves (i.e., us humans) to be particularly good at endurance running? A pack of hyenas will run down an antelope in a matter of some tens of minutes whereas for a group of human hunters it will take many hours. If anything, we humans would thus seem to be rather bad at endurance running. Even under the most optimal circumstances, this hunting method requires from us an insane amount of time and effort, in addition to involving a non-trivial risk of injury and death (of heat stroke). Doesn’t sound especially adaptive to me!

    And the fact that we modern humans (or some of us, anyway) demonstrably can run down ungulates still does not mean that earlier hominins did that too – even if they seemingly had the necessary physical traits. Human endurance running / persistence hunting requires intellect too. It takes very careful planning, both before the hunt and during it (suggesting that sophisticated language capabilities are needed); a Theory of Mind sufficiently well developed to be able to ‘think’ like a member of a different species, i.e., the prey antelope (or whatever) does and thus be able to anticipate its behaviour; and a considerable tolerance of delayed gratification. In short, it’s not at all certain that Homo erectus (sensu lato) was smart enough to hunt like this. Perhaps only H. sapiens possesses the necessary degree of intelligence for this kind of extreme persistence hunting? (And yes, I do realise that this question probably is unanswerable.)

    Link to this
  79. 79. David Marjanović 1:03 pm 11/9/2012

    …I don’t think anybody is reading this anymore, but… above, there has been speculation why our feet aren’t convergent on those of cursorial animals. I finally remembered what our feet are remarkably convergent on: those of sauropods. (I think Matt Bonnan was the first to point this out a few years ago.)

    Link to this
  80. 80. vdinets 6:09 pm 11/9/2012

    David: that means sauropods were endurance hunters. They probably chased their prey until it dropped, and then just stepped on it. I am calling Steven Spielberg with a proposal for Jurassic Park IV.

    Link to this
  81. 81. Metridia 9:03 pm 11/10/2012

    @Dartian:

    “There’s no reason that early hominids would have restricted themselves to a band of woods a hundred feet wide next to the rivers.”

    To address your response and clarify what I meant here, is that we were talking about hominids hunting. There is no reason a priori that humans would be limited to forests as dense as the aforementioned riverside forests, IF they are interested in chasing down prey and not ambushing it or scavenging.

    ““NOT closed-canopy forest”

    Please do not mis-quote me. ”

    Apologies if it seemed I was misquoting you. I took your use of ‘gallery forest’ as representing an environment with too much cover and not enough open ground, in contrast to the BBC San hunt’s environment, for an endurance hunt to be successful. My only point was that the putative Pliocene Turkana Valley environment was not really consisting of such a dense forest, and in fact was more similar to the type of environment the example of the San hunt took place in.

    @David- I’m still reading! In fact I am hoping Darren will undertake to write about these questions at some point.

    I think there is enough here on both sides to raise questions about full-fledged endurance hunter early hominins, but also to doubt that humans have apparent adaptations for throwing and jogging/walking for no reason.

    “our feet are remarkably convergent on: those of sauropods”

    I’d like to see that argument. Sauropods walked on columns with no obvious facility in terms of levers and tendons for running; humans don’t, and do.

    Link to this
  82. 82. David Marjanović 11:43 pm 11/11/2012

    Yes, humans can run, sauropods weren’t able to. But the heel, where sauropods probably had an elephant-style cushion instead, is pretty much the extent of the difference. Sauropod feet (not hands!) were much less digitigrade than those of all other dinosaurs, the metatarsals were spread (the metacarpals formed a column!), the toes curved laterally, and the feet were entaxonic – the first toe was the largest, and only the first 3 usually had claws.

    Link to this

Add a Comment
You must sign in or register as a ScientificAmerican.com member to submit a comment.

More from Scientific American

Scientific American Dinosaurs

Get Total Access to our Digital Anthology

1,200 Articles

Order Now - Just $39! >

X

Email this Article

X