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The Mulefoot and other syndactyles: not all pigs are cloven-hoofed

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


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I’m not just interested in ‘wild’ animals – I also think domesticated animals are fascinating. After all, my general philosophy is that there’s no such thing as a boring tetrapod. If you want me to be more specific about the merits of domesticates: well, while in cases they’re not all that different from their wild brethren (yet typically far more accessible), they’ve often had all kinds of crazy morphological variation bred into them by humans. Furthermore, there’s all that docility and friendliness that (sometimes) comes as part of the domestication deal. I particularly like learning about obscure breeds of domestic animals – the ones that you don’t hear about all that often.

One of the most peculiar pigs has to be the Mulefoot hog, so named as – if you know nothing of this pig, get ready to stagger backward, clutching heart, in surprise – it’s syndactyl. That is, it’s not cloven-hoofed: the two central digits on both the fore- and hindfeet are fused into one [Mulefoot image above from One Blog for the Kids!].

The very idea of a syndactyl artiodactyl must surely be a radical one if you’re not familiar with the variation seen in domestic pig breeds, but syndactyly has actually cropped up numerous times within various different breeds (it’s also been widely reported in cattle* [syndactyl cow limb shown here; from Donal O’Toole’s Inherited and congenital diseases of food animals and horses]). Aristotle reported syndactyl pigs in Greece in 350 BC; Gesner wrote about syndactyl pigs in England, Belgium and the Netherlands; Linnaeus wrote about their occurrence in Sweden. The remains of syndactyl pigs have also been reported from various archaeological sites in Ireland, Wales, England and France: based on the frequency with which syndactyl archaeological specimens have been discovered, Madgwick et al. (2011) recently suggested that the “the condition may have been more common in the past than commonly realised” (p. 12)

* Weirdly, when cattle do possess syndactyly, they tend to express it in the right forelimb alone (Leipold et al. 1969). Why?

While it seems that syndactyly might crop up randomly within individuals of various domestic pig breeds, the American Mulefoot is special in that syndactyly (also termed syndactylism in the domestic animal/veterinary literature) is a fixed trait. It seems that the Mulefoot breed first appeared in the early 1900s in the southwest USA; it was also apparently present in Mexico at this time. In Missouri and Arkansas it was known as the Ozark hog. Over 235 herds were registered across the US by 1910, and herds were also kept in Canada. Hardy, easy to fatten, and productive, part of the breed’s popularity might also be explained by the fact that it was believed immune to swine fever, cholera and foot and mouth disease (Porter 1993). Similar beliefs were also held about syndactyl pigs in Europe: there was such demand for syndactyl pigs round about the turn of the 20th century that breeders were apparently unable to keep up with demand. Alas, none of those claims about immunity are true, though it is conceivable that syndactyl pigs are less prone to the fungal foot diseases that can occur in cloven-hoofed pig breeds [Mulefoot... foot shown here from Foust Farms].

Like so many breeds that were once fairly popular and widespread, the Mulefoot sort of went out of fashion during the later part of the 20th century. That idea about extreme immunity was no longer such a big draw, since vaccines and medicines became cheaper and more widely available.

By the 1960s, the breed would likely have been lost were it not for the efforts of R. M. Holiday in Louisiana. During the 1970s he introduced genes from a herd in North Dakota, and this unfortunately led to the incorporation of several undesirable traits into the breed, including split hooves, ‘prick’ ears and wattles. Nevertheless, by 1985, Holiday’s herd was the only one left and only 200 individuals were in existence in 2006 (there are currently about 600). For more on this breed’s history, and on its characteristics, potential significance and perpetuation, visit the website of The American Mulefoot Hog Association.

Aside from its peculiar feet, the Mulefoot isn’t that remarkable. It’s typically black (sometimes with white markings) and with floppy ears and a soft hair coat [adjacent image shows mother Mulefoot with piglets; from Deer Run Farm].

So now you know. I recently acquired Valerie Porter’s Pigs: A Handbook to the Breeds of the World and am really enjoying learning about obscure domestic pig breeds. For previous Tet Zoo articles on domestic animals, see…

Refs – -

Leipold HW, Adrian RW, Huston K, Trotter DM, Dennis SM, & Guffy MM (1969). Anatomy of hereditary bovine syndactylism. I. Osteology. Journal of dairy science, 52 (9), 1422-31 PMID: 4312935

Madgwick, R., Forest, V. & Beglane, F. 2011. Syndactyly in pigs: a review of previous research and the presentation of eight archaeological specimens. International Journal of Osteoarchaeology doi:10.1002/oa.1260

Porter, V. 1993. Pigs: A Handbook to the Breeds of the World. Helm (Mountfield, Easy Sussex).

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! Follow on Twitter @TetZoo.

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





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  1. 1. Jerzy New 6:01 am 09/28/2011

    Single hoof is probably more stable and better support. So I wonder why none of such mutants during the evolution of artiodactyls started a new, successful group of species?

    Link to this
  2. 2. naishd 9:51 am 09/28/2011

    Indeed – I hope someone is thinking of the speculative possibilities as goes future evolution. Having said that, syndactyly in humans is known to be pleiotropically linked to problems like cleft palate, ectodermal dysplasia etc., and I’m not sure if these problem affect syndactyl artiodactyls. Does anyone know?

    Darren

    Link to this
  3. 3. keesey@gmail.com 10:02 am 09/28/2011

    The implications for kashrut…

    Link to this
  4. 4. naishd 10:21 am 09/28/2011

    I didn’t think of that… hell yeah, what _does_ it mean for kashrut? You’ve probably seen the famous “Are giraffes kosher?” article.

    Darren

    Link to this
  5. 5. BrianL 10:35 am 09/28/2011

    I’m reminded of the pig-footed bandicoot here, or at least its hindfeet. According to wikipedia “The hind feet had an enlarged fourth toe with a heavy claw shaped like a tiny horse’s hoof, with the other toes being vestigial:only the fused second and third toes being useful, and that not for locomotion but for grooming.” While *Chaeropus* was not truly pigfooted e.g. hoofed (I think, though it might have been an arbitrary case)and was not syndactyl, I do wonder if its digits might in any significant way parallel those of the Mulefoot and other syndactyl pigs.
    Also, given that its often said that marsupials can’t modify their front legs too much because of having to climb to the mother’s pouch at an extremely young age, how does this relate to *Chaeropus*’ unusual digits?

    Link to this
  6. 6. farandfew 11:31 am 09/28/2011

    Following on from what Jerzy said, I’ve always found it weird that – so far as I know – no species of crown-group tetrapod has ever had more than 5 digits despite it’s being a fairly common mutation in humans and one which – again so far as I know – isn’t linked to anything deleterious.
    Maybe the explanation is as simple as ‘five digits is enough’ and, for the artiodactyla, ‘unified hooves are no better than cloven ones’.
    But that second statement is possibly testable with some biomechanic modelling. Perhaps it’s already been done?

    Link to this
  7. 7. naishd 11:52 am 09/28/2011

    Well, novel preaxial and postaxial digits have of course been evolved by ichthyosaurs, and hupehsuchians and some cetaceans (Inia) have what appear to be short, accessory forefin digits. I’m not mentioning ailurids and giant pandas (and other bears) because their structures are obviously modified radial sesamoids.

    BrianL is right about the hoofed feet of Chaeropus: they counter, in part, the otherwise fine hypothesis that marsupials have been partly constrained in disparity by the supposed requirement for prehensile hands. But, then, marsupials have lost pouches on several occasions anyway, so there’s no obvious ‘rule’ that marsupials _have to_ start out with prehensile hands.

    Darren

    Link to this
  8. 8. Ranjit Suresh 12:00 pm 09/28/2011

    As for bandicoots, *Isoodon* newborn only have to make a short 1 cm trip, moving downwards, between the urogenital opening and the pouch.

    “The newborn of the bandicoot do not have a definite crawl to the pouch, as is seen in macropodids – they move with a snake-like wriggle down a moist 1-cm pathway between the urogenital sinus and the pouch. The mother bandicoot cleans the young, removing the membranes, and lies on one side then on the other, positioning the pouch so that the young nearly ‘fall’ into the pouch.”

    - Gemmell, R. T., Veitch, C. E., & Nelson, J. (1999). Birth in the northern brown bandicoot,
    Isoodon macrourus (Marsupialia: Peramelidae). Australian Journal of Zoology, 47, 517-528.

    Link to this
  9. 9. David Marjanović 12:26 pm 09/28/2011

    Details on Inia, please!

    Link to this
  10. 10. vdinets 12:39 pm 09/28/2011

    Jerzy: single hoof would probably be an advantage for a cursorial species of open plains. But for animals living on soft soil in dense forests or reedbeds, like pigs, it’s a disadvantage. Even-toed ungulates spread their hooves on soft soil, snow, rocks etc. to spread the weight and get more stability.
    Keesey: there are no implications for kashrut, because odd-toed ungulates are not kosher :-)

    Link to this
  11. 11. Heteromeles 12:57 pm 09/28/2011

    I remember an old article (from Stephen Jay Gould) about how the Romans and other ancient groups valued polydactylous horses. Didn’t Julius Caesar have one? Perhaps there’s a bit of a theme here, with more syndactylous pigs in the past? Breeders like to go for sports, after all.

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  12. 12. Zoovolunteer 1:49 pm 09/28/2011

    There are some breeds of chicken which are naturally polydactylous. “Silkie” bantams and their crosses with other breeds have multiple toes, sometimes different numbers on each foot. The mutation is associated with an alteration of the feather structure, which is where the breed gets its name. There seems from some of the other comments to be an association between alteration in foot development and various other developmental abnormaities – is there a geneticist who could offer an explanation?

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  13. 13. kmkohler 4:43 pm 09/28/2011

    There’s an essay by Stephen Jay Gould titled “Eight (or Fewer) Little Piggies” that discusses the question of why tetrapods tend not to have more than five digits. It’s probably sort of out of date, but still interesting.
    It’s available at sjgarchive.org, but unfortunately there doesn’t seem to be any way to link to it directly. You have to drill down from the top. It’s in the “B16″ collection.

    Link to this
  14. 14. Dartian 2:39 am 09/29/2011

    Darren:
    “I’m not mentioning ailurids and giant pandas (and other bears) because their structures are obviously modified radial sesamoids.”

    You’re not mentioning talpid moles either… ;)

    And yes, details on Inia would be appreciated.

    Link to this
  15. 15. naishd 4:32 am 09/29/2011

    Inia: numerous sources on this dolphin (there are one or two species, depending on whether you choose to accept the validity of I. boliviensis) refer to the presence of the sixth digit, represented only by a single phalanx. It’s postaxial. See in particular…

    Pilleri, G. & Gihr, M. 1976. The manus of the Amazon dolphin India geoffrensis (de Blainville, 1817), and remarks concerning so-called ‘polydactyly’. Investigations of Cetacea 7, 129-137.

    Polydactyly has been reported in other cetaceans (Cooper & Dawson (2009) recently reviewed digital anomalies seen in cetaceans), but only as an anomaly.

    Cooper, L. N. & Dawson, S. D. 2009. The trouble with flippers: a report on the prevalence of digital anomalies in Cetacea. Zoological Journal of the Linnean Society 155, 722–735.

    Darren

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  16. 16. naishd 4:49 am 09/29/2011

    Re: digital anomalies (like syndactyly and polydactyly) and deformities in other parts of the body (see comment 12)… yes, there is data from dogs, mice, guinea-pigs and other animals that strong negative pleiotropic affects are associated with digital anomalies – the reasons are complicated but are to do with interactions between genes during limb development. So, animals with digital anomalies frequently have all kinds of deformities in the appendicular and axial skeleton, also in various organ systems. Incidentally, lissamphibians aren’t affected in the same way, since their limbs develop later in ontogeny as seemingly separate modules. For extensive discussion of this subject do see…

    Galis, F., van Alphen, J. J. M. & Metz, J. A. J. 2001. Why five fingers? Evolutionary constraints on digit numbers. Trends in Ecology & Evolution 16, 637-646.

    Darren

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  17. 17. David Marjanović 7:16 am 09/29/2011

    Postaxial. Hm.

    Any association to the pisiform…?

    Link to this
  18. 18. Jerzy New 10:19 am 09/29/2011

    @vdinets: Similar anomalies are found in other artiodactyls. So why there never evolved one-hoofed cattle or antelopes?

    @naishd: I don’t like the explanation that marsupial limb development is constrained by crawling to pouch. First, fingers of baby kangaroo are really of little help in crawling, second, considering morphogenetic shifts, it would be possible to redevelop newborn forefeet during the time spend in the pouch, third, not all marsupials crawl as much as kangaroos. And what prevents evolution of female marsupial simply moving gently the newborn to the pouch? And are we sure that no marsupials actually do it? I read interesting study that kangaroo hopping is more efficient energetically. However, not all land mammals hop because hopping is unable to sustain long effort due to losing elastic properties – but Australia has random climate which doesn’t support long seasonal migrations like wildebeest.

    Link to this
  19. 19. naishd 10:34 am 09/29/2011

    Hi Jerzy: as I said in comment 7, the fact that some marsupials have done away with pouches altogether shows that the need for prehensile hands in newborns is not any sort of ironclad constraint on marsupial diversification. Furthermore, as described by Ranjit in comment 8, in some marsupials with pouch young (some bandicoots), the young crawl without the use of prehensile hands. Juvenile kangaroos, I believe, do have strong, grasping hands, but this evidently does not apply to all marsupials.

    I don’t think the evolution of hopping is necessarily anything to do with the modern Australian climate.

    Darren

    Link to this
  20. 20. Jerzy New 11:59 am 09/29/2011

    True.

    Just wondered why some evolutionary constraints really exist, although evolving around them is so easy – see mutations in digit number cropping up commonly in various domestic animals.

    I guess the mechanism is, that small adaptations of existing organs push the fitness too quickly. Revolutionary developmental shift has initially lower fitness, so becomes selected out.

    So evolutionary constraints are not absolute but relative. Often only slightly less fit.

    Link to this
  21. 21. naishd 12:22 pm 09/29/2011

    I think “domestic animals” is part of the answer there. Domestic breeds with extra digits and the resulting deformities and disadvantages live comfortable, assisted lives, but would they persist in the wild as breeding populations? And while you’re right that it seems easy to grow fewer/more digits, such changes may lead to maladaptive consequences elsewhere in the body. That’s weird, but organisms consist of connected, correlated parts, not bolt-on sections that grow independently of the others. You’ve heard of research indicating that mammals are mostly constrained to ‘short’ necks due to a genetic factor that involves susceptibility to cancer?

    Darren

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  22. 22. Christopher Taylor 7:36 pm 09/29/2011

    I’ve always wondered if the evolution of bounding rather than hopping in macropodids is due to constraints inherited from arboreal ancestors with the forelimbs significantly shorter than the hindlimbs. Seeing as the macropodids evolved much earlier than the development of the modern arid Australian climate, that definitely couldn’t be a direct factor, though I suppose it may have been a factor in the evolution of the large extra-cursorial Macropus species (ie. kangaroos and euros as opposed to wallabies).

    Indeed, having been into arid Australia on a number of occassions, hopping almost seems like it might be a rather bad way to get around. Much of Australia is covered by Triodia-dominated grassland. Triodia (spinifex) is hard, spiky and f***ing hurts, and whenever I see kangaroos jumping through it I can’t help but imagine that with every landing they are continually thinking: “Ow. Ow. Ow. Ow.” I was wondering just last week if anyone has ever investigated the prevalence or otherwise of skin lesions due to Triodia stabbings in roos.

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  23. 23. vdinets 10:58 pm 09/29/2011

    Actually, modern Australian climate is pro-migration. If you look at the fauna of the interior, most birds are nomadic. Even plague rats are kind of nomadic. And larger kangaroos in the interior also migrate to some extent.

    Link to this
  24. 24. Dartian 4:10 am 09/30/2011

    Jerzy:
    fingers of baby kangaroo are really of little help in crawling

    That’s a very dubious claim. As Darren said, newborn kangaroos have proportionally very strong, grasping hands.

    Incidentally: since kangaroos were brought up in a thread about monodactyly, it should be pointed out that some extinct macropodids (e.g., Procoptodon) had functionally monodactyl hindlimbs.

    I read interesting study that kangaroo hopping is more efficient energetically.

    That seems to be the case, yes. So much so, in fact, that instead of asking why kangaroos hop, one should perhaps rather ask why no (large) placentals hop in similar fashion. I don’t think that anyone has a wholly satisfying answer to that question, but some ideas are out there. For example, in his semi-popular book about kangaroos, Country: A Continent, a Scientist & a Kangaroo (2005), Tim Flannery suggested that hopping, while energetically efficient, is also potentially a rather hazardous way of locomotion for large mammals. The risk of injury is considerable, and thus natural selection has favoured structural adaptations that minimize stress on bones, joints and tendons. Specifically, kangaroo pelvic structure is (according to Flannery) more rigid than in placentals; kangaroos can get away with that because they, being marsupials, give birth to such tiny young. (The reason why small placentals, such as jerboas and kangaroo rats, are able to be saltatorial is probably precisely because they’re so small. Among placentals, the rabbit-sized Pedetes may be near the upper size threshold where bipedal hopping gets too mechanically costly/risky as a primary mode of locomotion.)

    Personally I find this suggestion intriguing but, unfortunately, Flannery doesn’t deal with it for more than just one short paragraph in his book. I’m not even sure if the idea is originally his, as I’ve been unable to find it expressed in the technical literature. (If some Tet Zoo reader knows the original reference, I’d much appreciate that information.)

    Christopher:
    as the macropodids evolved much earlier than the development of the modern arid Australian climate, that definitely couldn’t be a direct factor

    Indeed. The first macropodids appeared in the early Miocene (or possibly even already in the Oligocene), when Australia was much wetter than today. The earliest kangaroos were most likely forest-living.

    Vladimir:
    modern Australian climate is pro-migration. If you look at the fauna of the interior, most birds are nomadic

    Nitpick: ‘migratory’ and ‘nomadic’ aren’t quite the same thing. Migration is predictable and regular (often seasonal) movement; nomadism is unpredictable and irregular.

    Link to this
  25. 25. naishd 4:22 am 09/30/2011

    Hey, 24 comments (and now 25)… I must blog about weird pigs more often :) Some of my fellow SciAm bloggers want to know how it is than I managed to bring in such (comparatively) large numbers of comments. On that subject, the argument about scrapping registration and logging-in is still continuing – it’s a priority and we’ve made it clear how important it is.

    Darren

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  26. 26. David Marjanović 8:15 am 09/30/2011

    Specifically, kangaroo pelvic structure is (according to Flannery) more rigid than in placentals; kangaroos can get away with that because they, being marsupials, give birth to such tiny young.

    Immediately convincing to me. Compare the pelvis of any dinosaur to the pelvis of any placental that isn’t a xenarthran, and weep.

    Still not crying? Take this: sacroiliac joint.

    On that subject, the argument about scrapping registration and logging-in is still continuing – it’s a priority and we’ve made it clear how important it is.

    IMHO, the blockquote tag should be an even higher priority. What is the point in commenting when you cannot discuss?
    The automatic tripling of empty lines is annoying in this context, too.

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  27. 27. KarMannJRO 11:13 am 09/30/2011

    And maybe a reply button, so I can easily make it clear that I’m replying to David here?

    It’s technically not tripling of the empty lines; there are no extra line breaks between the paragraph element tags. So it must be in the CSS, which should make it even easier to fix. On the other hand, it implies that someone chose to make it that way in the first place.

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  28. 28. naishd 11:15 am 09/30/2011

    Ok, I’m taking all this to the backroom discussion forum thing (not its proper name).

    Darren

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  29. 29. farandfew 12:33 pm 09/30/2011

    I did not know about Icthyosaurs, Inia or (I’m ashamed to say) moles. The TREE article (comment 16) claims, however, that icthyosaurs (and moles) do not show real extra digits but modified other bones. I don’t think it mentions cetaceans. The only claim of such a thing at the species level the authors accept is from frogs. Is that mainstream? There did seem to be something cautious in Darren’s tone when he brought up the flippers.
    When one notes that a fixed mutation, while not deleterious in its own right, is nonetheless associated with other deleterious effects; it does not necessarily mean that pleiotropy is involved. Instead both effects could have been independently caused by the same factor, e.g. a mutagenic agent or, in the case of domestic animals, inbreeding, extreme selective pressure and pampering (of the kind Darren mentioned in comment 21).
    Now this isn’t my field so perhaps I’m making a stupid mistake but that TREE article does make me wonder a bit. They say that there’s strong evidence that polydactyly in humans is associated with deleterious effects but, at the same time, also note that these effects only occur in a small proportion of the polydactylous population. That small proportion is much higher than the proportion in the general population but it’s still small. They therefore claim that, as we would expect there to be pleiotropic effects, these must simply not have been picked up by the studies in the remaining, apparently healthy, people. Humans are the only non-domestic animal for which any equivalent evidence is given (presumably because they’re the only non-domestic animal for which enough data are available).
    On the other hand, there is equal – if not rather better – evidence presented in the paper that loss of digits is associated with deleterious effects. Yet many tetrapod lineages have lost digits and few, if any have gained them.

    Link to this
  30. 30. Ranjit Suresh 1:51 pm 09/30/2011

    Might it be that macropodids rely upon a more energy efficient means of locomotion because they have lower metabolic rates than analogous placental grazers?

    Link to this
  31. 31. Jerzy New 7:29 pm 09/30/2011

    Coming to pleiotrophic effects of increasing body parts – I wonder why artiodactyls could start with two horns/antlers and evolve four and five?

    Link to this
  32. 32. Spugpow 8:27 pm 10/3/2011

    And a third question:

    When Australia collides with Asia, will kangaroos and wallabies be among the native mammals to successfully penetrate into the old world?

    Link to this
  33. 33. vdinets 11:15 am 10/4/2011

    Spugplow: to collide with Asia, Australia would have to go through the equatorial rainforest zone first. Unless the humans and deforestation are still around, surviving in the rainforest would be difficult for large k-roos and wallabies. Tree and rat kangaroos, as well as bettongs and pademelons, might survive, but I am not sure their anti-predatory defenses are good enough to survive cats and viverrids. On the other hand, larger sengis of E Africa closely resemble rat kangaroos, but do survive placental predators.

    Link to this
  34. 34. Ranjit Suresh 3:31 pm 10/4/2011

    Why can’t rainforests support medium to large marsupial herbivores? Large artiodactyls and perrisodactyls seem to do just fine in them, as do large bovids. Also, don’t forget Australia was not always as arid as it is today. Of course, this may come again to the issue of being constrained by the need for prehensile forelimbs, which means that cursorial marsupials suited for such habitats are not likely to evolve.

    I suspect only a minority of marsupial lineages would survive an Australia-Southeast Asia interchange.

    Link to this
  35. 35. vdinets 10:01 pm 10/4/2011

    Because hopping through the rainforest would be too difficult. In New Guinea, wallabies are confined to savanna patches in the far south.

    Well, three orders of American opossums did survive repeated placental incursions, so you can’t be sure. The interchange is millions of years away. By that time marsupials, now living with rats, dingos and cats, could evolve efficient anti-placental tactics.

    Link to this
  36. 36. Dartian 3:06 am 10/5/2011

    Vladimir:
    larger sengis of E Africa closely resemble rat kangaroos

    Rhynchocyon and Hypsiprymnodon are ecologically different, though; the former are insectivorous whereas the latter is a herbivore/omnivore.

    In New Guinea, wallabies are confined to savanna patches in the far south.

    That’s not true. The brown dorcopsis Dorcopsis muelleri lives in the western part of New Guinea (and on some nearby islands), the white-striped dorcopsis Dorcopsis hageni lives in northern New Guinea, and the small dorcopsis Dorcopsulus vanheurni is found in the central parts of the island.

    Link to this
  37. 37. Jerzy New 7:39 am 10/5/2011

    @34
    AFAIK, there was a rich fauna of large marsupials in Australian rainforests, but they gone extinct after human arrival. Many of them were actually non-hopping rhino-like relatives of wombats (diprotodons, zygomaturus etc.)

    BTW, one thing I was curious about for a long time. New Guinea and N Australia, being rainforest, would have verey interesting extinct megafauna. But almost nothing is written about it, everything is focused on semidesert parts of Australia.

    Link to this
  38. 38. David Marjanović 7:58 am 10/5/2011

    Many of them were actually non-hopping rhino-like relatives of wombats (diprotodons, zygomaturus etc.)

    …and then there were the giant grasping kangaroos like Procoptodon. It isn’t a problem to be cursorial and have grasping forelimbs if you’re bipedal!

    BTW, one thing I was curious about for a long time. New Guinea and N Australia, being rainforest, would have verey interesting extinct megafauna. But almost nothing is written about it, everything is focused on semidesert parts of Australia.

    Rainforest soil is shallow and acidic. It does not preserve bone.

    Link to this
  39. 39. vdinets 12:03 pm 10/5/2011

    Dartian: true and true. But I was talking about general shape, size and predator avoiding abilities of sengis vs. rat k-roos, and about large wallabies. Smaller species like pademelons do fine in the rainforest (I think the largest of them is Parma wallaby).

    Link to this
  40. 40. Dartian 2:55 am 10/6/2011

    Jerzy:
    New Guinea and N Australia, being rainforest, would have verey interesting extinct megafauna. But almost nothing is written about it

    Well, there are logistical and political reasons why New Guinea hasn’t received as much paleontological (or any other kind of scientific) attention as Australia. In particular, the Indonesian-controlled western part, Irian Jaya, hasn’t always been easily accessible to foreign scientists.

    However, we aren’t entirely ignorant of New Guinea’s geological past. I suggest that you (and Ranjit) look up this book (note the “New Guinea” part in the title) and the references therein:

    Long, J., Archer, M., Flannery, T. & Hand, S. 2002. Prehistoric Mammals of Australia and New Guinea. University of New South Wales Press, Sydney.

    David:
    Rainforest soil is shallow and acidic. It does not preserve bone.

    Fossils in the tropics are frequently found in caves, though. (Homo floresiensis, anyone?)

    Vladimir:
    I was talking about general shape, size and predator avoiding abilities of sengis vs. rat k-roos

    Yes, but surely we should expect that significant differences in (for example) diet between two taxa correspondingly imply significant differences in (for example) diel activity pattern, range size, substrate use, and/or social behaviour – which, in turn, presumably implies significant differences in (for example) vulnerability to predation. In other words, superficial similarity in physical appearance between Rhynchocyon and Hypsiprymnodon isn’t enough reason to presume them to be evolutionarily analogous taxa.

    large wallabies

    ‘Large wallaby’ is pretty much an oxymoron. More importantly, however, we know that there were also larger macropodids present in New Guinea in the past. For example, several species of Protemnodon (which reached sizes similar to, or slightly larger than, the largest extant kangaroos) lived there in the Pliocene and the Pleistocene; according to the earlier-mentioned Tim Flannery (who has discovered many of these fossil New Guinean marsupials), the paleoenvironment of the two known Pliocene species was lowland rainforest. Thus, it seems that any claims to the effect that large macropodids can’t adapt to living in rainforests need some qualification.

    Link to this
  41. 41. David Marjanović 7:59 am 10/6/2011

    A few decades ago, there were feral kangaroos in England and Germany. They did quite well, hadn’t it been for the hunters.

    Fossils in the tropics are frequently found in caves, though.

    When there are caves, yes!

    Protemnodon

    Heh. Temnodon and Temnodontosaurus. Tyrannus and TyrannosaurusTylosurus (not a tetrapod) and TylosaurusMastodon and Mastodonsaurus, both named by Victorian-age scientists who apparently thought in exactly the ways Freud believed they thought.

    Link to this

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