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Mystery big cat skulls from the Peruvian Amazon not so mysterious anymore

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


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Skulls and accompanying life restorations of (A) the Peruvian 'Anomalous jaguar' and (B) 'Peruvian tiger'; image by Gustavo Sanchez.

Scientific projects are very often years in the making. Within the past few days, I’ve had a new paper appear in the open-access journal PeerJ. It’s co-written with Manabu Sakamoto, Peter Hocking and Gustavo Sanchez. Therein, we examine and, we think, resolve the previously vexing identity of two big cat skulls obtained in the Peruvian Amazon (Naish et al. 2014).

Long-time Tet Zoo readers with exceptionally good memories might recall the ver 2 article – pu­­­­­­blished way back in June 2007 – in which I asked that most vexing of questions: “Peter Hocking’s big cats: where are you now?”. As you’ll know if you recall that article, or if you know a reasonable amount about South American mammalogy or cryptozoology, back in 1996, Peruvian ornithologist Peter Hocking announced the procurement of two skulls belonging to pantherine cats, suggested by him to represent two of the ‘mystery’ cats said by local people to inhabit the forested highlands of Peru’s Pasco Province (Hocking 1996).

Illustration by Peter Visccher, depicting Peruvian cryptids. The primate is the 'Isnachi'. From Greenwell (1994).

Hocking – perhaps best known in the world of zoology for the several bird species he has to his name – has long been collecting anecdotes from indigenous Peruvians about mystery animals: animals that don’t seem to match those known to scientists and which might represent undiscovered taxa (Hocking 1992, 1996, Greenwell 1994). Among these is the so-called ‘striped tiger’, a reddish, jaguar-sized cat marked with white, unbranched stripes. Its paradoxical name results from the fact that ‘el tigre’ is the name used across much of South America for Panthera onca, the Jaguar. In other words, it’s meant to be a ‘Striped jaguar’. We opted to use the name ‘Peruvian tiger’ for this alleged animal. Then there’s a second, Jaguar-like big cat, said to have solid black irregular spots, not rosettes like a Jaguar. We use the term ‘Anomalous jaguar’ for this animal. The adjacent illustration by Peter Visccher – produced to accompany an article by the late cryptozoologist Richard Greenwell – shows the Peruvian tiger and Anomalous jaguar together with a few other Peruvian mystery animals reported by Hocking (Greenwell 1994), though the illustration errs in giving the ‘Peruvian tiger’ dark stripes rather than white ones. The big black cat included in the scene is the ‘Yana puma’, an animal that might not be a cat after all, but a local name for the Spectacled bear Tremarctos ornatus.

Old news now is that Hocking managed to get hold of skulls said to belong to both the ‘Peruvian tiger’ and ‘Anomalous jaguar’. Preliminary observations on the anatomy and proportions of these skulls indicated that both were different from those of Jaguars.

'Peruvian tiger' (at left) and 'Anomalous jaguar' skulls in anterior view (and pretty much to scale). Photos by Peter Hocking.

In view of the possible significance of these animals (are we really talking about the possible existence of new living species or subspecies or, at least, local variants or morphs of big cat?), the discovery of actual, physical remains was pretty exciting. Alas, while these skulls were figured and briefly discussed on a couple of occasions (Hocking 1996, Bille 1997), a detailed or proper analysis never appeared, hence my 2007 Tet Zoo article. What was happening to these specimens? Well, nothing.

At top: a box from Peru, containing replica cat skulls. Exciting! At bottom: damage incurred to the 'Peruvian tiger' skull during transport. Unfortunate, but fixed by Gustavo.

A plan was formulated. It turned out that correspondent and Tet Zoo reader Gustavo Sanchez of Fundación Neotrópico in Tenerife knew Peter Hocking and was in correspondence with him. Peter was still in possession of the skulls and would make plaster replicas and send them to Europe. A collaboration was born. Gus received the replicas in November 2009 (unfortunately, they were substantially damaged during transit and repair was required). I, in turn, was very excited to receive them in February 2010. As you can see from the photos here, Peter is obviously a master at making amazingly good plaster replicas of skulls.

Work could begin, and I now brought in Manabu Sakamoto (then of the University of Bristol), the aim being to take measurements from the skulls and incorporate these into the large set of cat skull data that Manabu had been building up for other projects (see Sakamoto & Ruta 2012). Manabu and I did this work back in February 2011. This explains why photos of Manabu and myself, holding plaster replicas of big cat skulls, featured on Tet Zoo back in January 2012.

One of our several scatterplots. This one (showing the first and third linear discriminants plotted against each other) shows both Peruvian skulls plotting at the edge of the Jaguar cloud. Image from Naish et al. (2014).

36 cranial and 13 mandibular measurements were taken from both skulls. These were then subjected to linear discriminant analysis (LDA), a statistical technique that unites variables as linear combinations for the purposes of comparison and discrimination. Scatterplots were generated to see how linear discriminants calculated for the Peruvian skulls compared to those of other cats. Both skulls were unquestionably close to Leopard P. pardus and Jaguar, though they grouped separately from both species, closer to Leopard, and closer to Jaguar, respectively, in different analyses. However, by far the most robust results placed them close to the Jaguar cloud. Admittedly, they were at the edge of Jaguar morphospace, and the results from the analyses of the mandibular dataset were not particularly strong (Naish et al. 2014).

Both skulls looked to be those of Jaguars in any case: they have the obviously robust rostrum and dentition typical of this species as well as the broad coronoid process, concave dorsal surface to the nasals, and concave, flexed surface to the dorsolateral part of the maxilla (Naish et al. 2014). It should also be added that the skulls possess characters typical of Panthera, and typical of the Panthera clade that includes all species except the Snow leopard P. uncia (Naish et al. 2014).

(A) 'Anomalous jaguar and (B) 'Peruvian tiger' skulls in oblique dorsolateral view to show the flexed, concave dorsolateral part of the maxilla present in both specimens. Photo by Barry Marsh, from Naish et al. (2014).

The conclusion has to be that both skulls are of Jaguars after all, in which case the unusual coat colours and patterns reported for these individuals represent genetic anomalies of the sort already well known among wild cats. Abnormalities of just about every conceivable sort are on record as it is: Leopards and Cheetahs with stripes or pseudo-stripes are known, for example, rendering it plausible that reports of striped ‘Peruvian tigers’ refer to sightings of weird, aberrant Jaguars. Alternatively, it’s possible that the ‘Peruvian tiger’ skull didn’t really belong together with the striped pelt it was reportedly in original association with. We can’t explore this possibility any further since that pelt (and any other remains) were sold to an unknown party (Naish et al. 2014). If you’re wondering about DNA retrieval… given that the original skulls were defleshed and then boiled by the hunters who obtained them, we opted not to attempt DNA analysis. We do recognise, of course, that this might still be do-able.

A tangent on the backstory

Manabu, hard at work measuring cat skulls in 2011. Image by Darren Naish.

The plan throughout this project is that we’d have a publishable paper, whatever the results. If the skulls really did represent one or two new taxa: that’s great – publication! But if the skulls could be identified as belonging to a known taxon: that’s great – publication! And let us not forget that there’s been a reasonable amount of interest in the outcome of this specific case.

As those of you who are publishing scientists will well know, part of the challenge of doing science comes not just from doing the science itself, but from getting your research published. Finding a ‘home’ for a given manuscript can be hard, and the ideas, recommendations and criticisms of editors and reviewers can be difficult or even utterly impossible to take account of. A specific problem we had with this manuscript is that some parties didn’t consider that it examined a hypothesis worth testing. One editor turned down the manuscript because they said that it “lacked a scientific rationale”, their thinking apparently being that, since there isn’t an active controversy over the number of living Panthera species in South America, the project is redundant and not worthy of publication. I disagree emphatically with this perspective – there’s definitely a mystery here worth analysing – and I thus ended up wasting weeks of time fighting with editors and corresponding with people higher up the chain of command. While people at the journal concerned did eventually change their mind and say that they were prepared to reconsider the manuscript, I had to give up on them because I just couldn’t find the time to meet their demands for resubmission. Horror stories like this abound in academic publishing. Remember that I do academic research ‘in spare time’ and am not paid to do it.

Lest we forget how awesome Jaguars are, here's one of several images from a sequence in which a Brazilian Jaguar swims across a river to ambush, catch and kill a large caiman. Image by Justin Black, licensed under Creative Commons Attribution-Share Alike 3.0 Unported license.

Here’s where PeerJ comes in. PeerJ is a recently launched, open-access, peer-reviewed online journal, its stated mission being to “help the world efficiently publish its knowledge”. A really painful part of the academic process concerns formatting. Every time you submit a manuscript to a journal, you’re expected to comply specifically to its style. And, seeing as virtually every single journal has its own style (in terms of how works are cited, how references are written, how figures are designed, and so on), many, most or all of us have wasted pointless, painful hours or days of our lives reformatting journal articles (this despite the fact that all technical journals have their own editorial staff and are typically owned by publishing companies anyway!). [Adjacent image by Justin Black.]

PeerJ is special in that it doesn’t have its own style – it merely demands that your manuscript is scientifically valid, novel and conforms to usual scientific protocol. This is a major plus-point: no painful reformatting required if your manuscript was previously designed with another journal in mind. To publish there, you do have to pay a $99 lifetime membership fee. Without getting into the finer points of my academic finances, let’s just say that I owe huge thanks to my excellent friends Mike P. Taylor and Matt Wedel of SV-POW! for paying for my subscription as a birthday present.

It took some years, but we got there in the end. Naish (left) and Sakamoto with replica pantherine skulls.

Anyway, the manuscript ended up in PeerJ. So, it only took me four years to get the research done and the paper published. That’s not great, but it’s not all that bad either, all things considered. I’m really pleased with everything about the experience of publishing with PeerJ and will definitely be submitting work there again. I should add that I really wanted this research to appear in an open-access journal since I think it’s important that it’s available to interested parties in Peru, not locked up behind a subscription paywall.

I think we can now say with confidence that those two skulls are those of Jaguars after all. Does this resolve the whole enigma of ‘Peruvian tigers’ and ‘Anomalous jaguars’? That question is harder to answer, and as usual we wait for good additional data before we can proceed further. And I’ll end by saying that there are other pieces of ‘mystery cat’ evidence out there that could also do with being analysed in the peer-reviewed technical literature…

For previous Tet Zoo articles on cats and other carnivorans, see…

Refs – -

Bille, M. 1997. News and comment. Exotic Zoology 4 (2), 4.

Greenwell, J. R. 1994. Mean mammals of the mountains. BBC Wildlife 12 (6), 33.

Hocking, P. J. 1992. Large Peruvian mammals unknown to zoology. Cryptozoology 11, 38-50.

- . 1996. Further investigations into unknown Peruvian mammals. Cryptozoology 12, 50-57.

Naish, D., Sakamoto, M., Hocking, P. & Sanchez, G. 2014. ‘Mystery big cats’ in the Peruvian Amazon: morphometrics solve a cryptozoological mystery. PeerJ 2:e291; DOI 10.7717/peerj.291

Sakamoto, M. & Ruta, M. 2012. Convergence and divergence in the evolution of cat skulls: temporal and spatial patterns of morphological diversity. PLoS ONE 7:e39752 DOI 10.1371/journal.pone.0039752

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. Sordes 7:41 am 03/10/2014

    That´s after all really quite interesting, even if it (sadly) doesn´t mean they are something really novel. But it´s good to see you have finally finished your analyses and published this paper, congratulations!

    What I wanted to ask, how large are those skulls, and where do they range within the size range of jaguars? On the photos where you and Manabu are holding the casts, they look comparably small. It would be especially interesting to know how well they fit into the size of jaguars in the area where they were collected, as – I don´t have to tell you (but perhaps it´s new to some other readers)- jaguars have a really dramatic range of body size within their vast distribution area.

    Link to this
  2. 2. ekocak 9:09 am 03/10/2014

    Congrats on publishing the paper! I think it’s kinda interesting that it’s that difficult to get a scientific paper published–is it that since the results aren’t a novel species there’s less interest? It’s still a result after all. I think the idea that there are such weird possible variations out there is equally interesting.

    Link to this
  3. 3. Jerzy v. 3.0. 9:11 am 03/10/2014

    Interesting stuff! What would be cool is DNA extraction. All known felids have the same genetics of coat color, and the genes are mostly known. So it would be incredibly cool to check if these cats have genetic mutations responsible for shifted color pattern.

    I guess the large primate didn’t materialize?

    Link to this
  4. 4. Tayo Bethel 11:20 am 03/10/2014

    Great article. Even if there isnt a new species involved, it’s still enlightening to see the amount of variation in P. onca.
    What are the anatomical and behavioral characteristics of the pantherineclade, besides large size and the ability to roar? *Jaguars dont roar, do they*

    Link to this
  5. 5. Heteromeles 11:25 am 03/10/2014

    Great that this got published. As for coat color genetics, that would be a wonderful contribution. Except…white stripes on a reddish background? I’ve never seen that on any cat. are we talking a tiger without the black, somehow?

    Link to this
  6. 6. naishd 11:31 am 03/10/2014

    Thanks for comments so far. Some brief responses…

    On the sizes of the specimens (comment # 1): remember that all measurements can be downloaded from the paper (‘List of specimens with measurements’ is right at the bottom). The ‘Peruvian tiger’ skull is 218 mm long, and the ‘Anomalous jaguar’ 250 mm long. These are the sorts of sizes you’d expect for Jaguar: bigger than most leopards, snow leopards and pumas, but way smaller than tigers and lions.

    ekocak (comment # 2): the fact that this paper reports negative results explains part of the reason for the difficulty in publishing. Journals increasingly want gee-whiz results that they can spin in news stories, not mundane conclusions along the lines of “we didn’t find anything novel or interesting”.

    Tayo (comment # 4): I assure you that Jaguars do roar! It’s coarse, guttural, and with a bit of ‘wood-sawing’, leopard-style thing. Lots of recordings on youtube.

    Link to this
  7. 7. naishd 12:29 pm 03/10/2014

    re: “white stripes on a reddish background?” (comment 5). I’ve been wondering if the reports could describe pseudomelanism. A pseudomelanistic Leopard photographed in Parambikkulam Tiger Reserve in 2012 looked dark, with pale pseudo-stripes being left between its coalesced dark markings. If the background colour was dark brown (as is known for other pseudomelanistic cats), pale ‘stripes’ on a ‘reddish’ background would be the result.

    Link to this
  8. 8. Tayo Bethel 12:32 pm 03/10/2014

    @Naishd:
    Thanks. Would still like to know which morphological and behavioral traits characterize the Pantherine cats. Oh for a time machine with an audio recorder attached so we could document vocal evolution in pantherine cats–how the guttural, sawing roars of leopards and jaguars gave rise to the full-throated bellows of lions and the yowling roars of tigers.

    Link to this
  9. 9. KarlShuker 2:38 pm 03/10/2014

    Good to see this published. Additionally, in my recent book Cats of Magic, Mythology, and Mystery (2012), I devote a lengthy chapter to South American mystery felids that includes various sightings and reports of cats closely corresponding to the Anomalous jaguar, plus a detailed full-colour illustration from the 19th Century of a supposed jaguar whose very pale, speckled, non-rosetted pelage very closely resembles that of the Anomalous jaguar.

    Link to this
  10. 10. Sordes 2:41 pm 03/10/2014

    Thanks Darren, I´ve really overlooked the link to the full paper.

    Link to this
  11. 11. naishd 3:36 pm 03/10/2014

    Karl – I did think about your book, but haven’t seen a copy yet so decided not to cite it. Does it include a discussion of Hocking’s cats? (if so, I’ll add a citation above). Thanks for the comment.

    Link to this
  12. 12. KarlShuker 9:44 pm 03/10/2014

    Hi Darren, Yes, in my book I included a discussion of all of the Hocking mystery cats, and I noted that a paper examining the Hocking skulls of the so-called speckled tiger (your Anomalous jaguar) and striped mystery cat (your Peruvian tiger) was in the works – I did know the results as you’d kindly mentioned them to me in confidence some time earlier, but obviously I made no mention of them in my book as your paper hadn’t been published.

    Incidentally, further to what I wrote in my previous comment, here is an excerpt from my book, ‘Cats of Magic, Mythology, and Mystery’ (CFZ Press: Bideford, 2012), re other possible Anomalous jaguar examples:

    “One other controversial cat reported from South America that is somewhat reminiscent of Peru’s speckled tiger is the cunarid din, mentioned by the Wapishana Indians of Guyana and Brazil to Stanley E. Brock. In ‘Hunting in the Wilderness’ (1963), Brock describes this strange cat as follows:

    ‘The cunarid din is quite like the ticar din [normal jaguar], except that the ground colour is nearer white than orange or yellow. The Indians say that the white kind always attain a much larger size than the former, but this is doubtful as a fact. The spots are often finer on the fore quarters and spaced further apart, and there are noticeably fewer spots within the rosettes along the sides of the body, giving the skin a rather leopard-like appearance.’

    Moreover, while browsing through a copy of Scottish naturalist Sir William Jardine’s classic ‘Natural History of the Felinae’ (1834) recently, I was startled to discover a colour plate of a very odd-looking jaguar – whose paler-than-normal coat lacked this species’ familiar, clearly-defined rosettes and instead was patterned entirely with a heterogeneous array of solid black speckles and blotches. According to the plate’s caption, this jaguar was a native of Paraguay. Consequently, always assuming of course that it had been depicted accurately, this suggests that speckled jaguars or jaguar-like cats have also occurred here in the past. Perhaps they may still do so today.”

    Link to this
  13. 13. Jerzy v. 3.0. 3:59 am 03/11/2014

    @KarlShuker
    It might be the same mutation as in some cheetahs, leopards in Zanzibar and so-called ‘servaline’ servals.

    Congrats, Darren, in any case!

    If you gave up, it would start another story about a specimen of cryptid obtained and lost… Bias on publishing positive results perpetuates cryptozoological tales.

    Link to this
  14. 14. barndad 5:04 am 03/11/2014

    If anyone is interested (as I was), Jardine’s book is free to download via Google books. The image Karl refers to is Plate 11.

    Link to this
  15. 15. naishd 5:34 am 03/11/2014

    Thanks, Karl, for the substantial extra info – it’s tempting to wonder whether these cats are all references to the same (rare) Jaguar colour morph. Of course, the new paper discussed here could be seen as another instance in which a cryptozoological investigation has resulted in a peer-reviewed analysis. As I hint at in the article, I’d really like to see people properly analyse some of the other bits of data out there — what’s happening with the ‘spotted lion’ skins, for example? In fact, where are they – does anyone know?

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  16. 16. Cahokia 7:44 am 03/11/2014

    I have to confess that it’s become my standard operating procedure to skip to the end of Naish’s cryptozoological posts to confirm that the animal in question is after all nothing special before going back to the beginning and reading the article through.

    Link to this
  17. 17. naishd 9:08 am 03/11/2014

    Cahokia: maybe one day you’ll be very surprised. Maybe… (maybe not).

    Link to this
  18. 18. KarlShuker 2:36 pm 03/11/2014

    @Jerzy v. 3.0. – Great minds think alike?! Quoting once again from my book ‘Cats of Magic, Mythology, and Mystery’ (2012): “Genetically, the presence of solid black speckles reported for Peru’s ‘speckled tiger’ rather than well-formed rosettes is anomalous. The only comparable case is that of the speckled servaline morph of the serval Leptailurus serval (see Chapter 27), and a couple of servaline-like cheetahs that I have dubbed cheetalines (see Chapter 19).”

    @naishd – Darren, I forgot to mention in my previous comments above that my book also contains a mention of a speckled mystery cat from Ecuador: “While visiting southern Ecuador’s Morona-Santiago province in July 1999, Spanish cryptozoologist Angel Morant Forés learnt of several mystery cats said to inhabit this country’s Amazonian jungles. Upon his return home, he documented them in an online field report, entitled ‘An investigation into some unidentified Ecuadorian mammals’, which he uploaded in autumn 1999 onto French cryptozoologist Michel Raynal’s website, the Virtual Institute of Cryptozoology, where it is still accessible today (at http://cryptozoo.pagesperso-orange.fr/welcome.htm). These very intriguing crypto-felids include: A white-coated cat with solid black spots known as the shiashia-yawá, recalling the cunarid din of Guyana and Brazil, and Peru’s speckled tiger, but smaller (said to be intermediate in size between a jaguar and an ocelot). Angel considers it possible that this felid is merely an albinistic jaguar, but as already discussed in relation to the speckled tiger, such an identity would not explain its solid black spots, which sound very different from the familiar rosettes of normal jaguars.”

    Link to this
  19. 19. naishd 3:26 pm 03/11/2014

    Great stuff – thanks for adding this, Karl.

    Link to this
  20. 20. Heteromeles 9:32 am 03/12/2014

    I don’t know the present range of jaguars at all well, but I do know that they’re under threat in much of their range. I wonder if we’re going to (or starting to) see more aberrant jaguars due to inbreeding in isolated populations.

    Link to this
  21. 21. Yodelling Cyclist 10:08 am 03/12/2014

    Standard disclaimer deserves repeating: I’m not a biologist/palaeontologist or even a biochemist, so should anyone find the time to reply please use small words.

    Question: How reliable do you think the morphological tests you subjected the skulls to are when it come sto species discrimination? From the above scatter plot, it seems that were one to be confronted with a P. Leo and P. Tigris skull (without any other data, and possibly just ignorant about cats in all respects other than intraspecific variation), one could reasonably fail to recognise that there were more than one species present? A similar situation seems to be present (again, based on the scatter plot) with P.Uncia and Pu. Concolor.

    Best wishes
    Yod

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  22. 22. Yodelling Cyclist 10:19 am 03/12/2014

    Also, a massively off topic question, referring way back to previous discussions of the protein intake that sauropodlets required to grow rapidly (assuming that rapid growth did occur), is anything at all known (and if so, how?) of the fungal community in the Mesozoic?

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  23. 23. KarlShuker 12:25 pm 03/12/2014

    Earlier today, I happened to discover online a beautiful full-colour plate of two mysterious big cats with whitish background-colour fur and covered in small solid black speckles that may – or may not – be relevant to the Anomalous jaguar. The plate was published during the 1750s, and appeared in Albertus Seba’s famous four-volume ‘Thesaurus’. I have written a ShukerNature blog post about this unexpected find, which can be accessed here: http://karlshuker.blogspot.co.uk/2014/03/albertus-seba-and-pair-of-speckle.html

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  24. 24. imhennessy 8:34 pm 03/12/2014

    Yod, I have long been under the impression that P. leo and P. tigris are indistinguishable if only the skeleton is examined. I have no idea what source I picked that up from.

    Ivan

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  25. 25. vdinets 5:58 pm 03/13/2014

    here is a nice overview of cranial differences between lions and tigers: http://mambobob-raptorsnest.blogspot.com/2008/07/lion-and-tiger.html

    Link to this
  26. 26. DavidMarjanovic 6:26 am 03/14/2014

    Oh, wow. Those differences are really easy to see, and the post says they’ve been known since 1906. The claim that lions and tigers have identical skeletons is really common at least in the non-primary literature.

    Link to this
  27. 27. DavidMarjanovic 6:27 am 03/14/2014

    (identical except for average size)

    Link to this
  28. 28. Heteromeles 10:40 am 03/14/2014

    Of course, people still get into arguments about whether Panthera atrox, the extinct American lion, was a jaguar or a lion. We’re lucky that the mass extinction has done away with so many of the confusing Panthera lines, I guess. As for P. atrox, I’ve seen repro skulls at close range (they’re on display at the San Diego Zoo and the SD Natural History Museum just down the road), and the darned thing looks like a Neanderthal lion, oversized nose and all.

    Link to this
  29. 29. Yodelling Cyclist 1:00 pm 03/14/2014

    That’s all cool (I mean that sincerely) but it actually confuses the question, as it implies that, yes the species can be differentiated, but not by the metrics that Darren’s employed. Which (and I type this in a small voice with due deference to the learning ranged around this blog) kind of shows that these metrics aren’t capable of reliable species discrimination in Panthera. Furthermore the discriminating characters appear to be determined post hoc, i.e. “here’s a lion skull, here’s a tiger, what are the differences?”, rather than “hey look at these two wildly different skulls.”

    I should further point out that I’m not really arguing in favour of a cryptic South American big cat – I have genuinely no idea about that. I’m just not convinced by (or perhaps I just don’t properly understand) the methodology.

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  30. 30. Tayo Bethel 1:50 pm 03/14/2014

    I suspect that if Panthera atrox were alive and kicking we would have little trouble telling if it was a lion or giant jaguar. After all, externally the Panthera cats are all fairly distinct from each other–its only when it comes to the skeleton that problems of identification crop up.

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  31. 31. Heteromeles 2:10 pm 03/14/2014

    @Tayo: You’d think so, right? Unfortunately, as I understand the analyses, P. atrox turns out to be a mosaic of characters, some of which are jaguarish, some of which are lionish. My guess is, if it were alive, we’d be giving it its own name, and not something silly like “American Lion.” Imagine deducing the ecology of a tiger if all you had were bones and living lions to compare it to. We’d probably be calling it the “extinct Siberian lion” or some such.

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  32. 32. vdinets 5:33 pm 03/14/2014

    Here is a nice page with photo line-ups of big cat skulls, including the “American lion”.

    Unfortunately, you can’t estimate the degree of intraspecific variation from those photos. I haven’t seen that many lion skulls, but tiger skulls can be quite variable in appearance. Still, judging from the photos, I would easily bet a few bucks on P. atrox being a full species.

    On the other hand, there is a good chance that P. atrox and P. leo were just terminal forms in a cline with P. spelaea in the middle. Here is a line-up of these three forms
    (That photo is from a page on Carnivora website that isn’t open to outsiders, but still shows up in Google searches. I guess it’s time for me to join…)

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  33. 33. Tayo Bethel 8:32 pm 03/14/2014

    @Heteromeles
    Point taken. That scenario would also apply to jaguars and leopards, and those two,unlike the lion and tiger, actually share ecological similarities. I’ve seen part of the paper on Panthera atrox. It would be nice if there was a way to separatesize-related morphologicalcharacters, which might account for the “lionish” characters, from the more diagnostic characters. Orhas this been done>

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  34. 34. vdinets 8:40 pm 03/14/2014

    One thing I learned while reading about Panthera skulls is that tigers have larger brains than lions. I wonder if this explains why tigers quickly learn to drag tourists out of open jeeps, while lions don’t. This also goes contrary to the patterns found in primates, where brain size correlates with group size.

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  35. 35. Dartian 6:22 am 03/15/2014

    David:
    Those differences are really easy to see

    In those two particular skulls, maybe (also, that tiger’s canine teeth are relatively larger and longer than that lion’s). But what about individual variation?

    The claim that lions and tigers have identical skeletons is really common at least in the non-primary literature.

    Well, those were skulls in Vlad’s links, not entire skeletons. I suspect that the postcranial differences between lions and tigers are even less obvious than the cranial ones. There are, of course, some subtle postcranial morphological differences between lions and tigers. For example, the tail tip of the tiger is typically much more strongly curved than that of the lion – as you can see, e.g., here. I don’t know, however, if one could tell that by just comparing their tail vertebrae.

    Heteromeles:
    the darned thing looks like a Neanderthal lion, oversized nose and all

    Dunno about the Neandertal comparison, butatrox skulls are indeed huge.

    Vlad:
    tigers quickly learn to drag tourists out of open jeeps

    When and where has this happened?

    Link to this
  36. 36. Heteromeles 11:23 am 03/15/2014

    @Dartian: what I meant by “Neanderthal lion” isn’t that the skulls are huge (and they are), but that, compared with a modern lion, P. atrox muzzles are proportionally wider, relative to their eye sockets. You can see that in these images (ignore the chatter around them. I have no idea where the original images came from). It’s reminiscent of the comparison between Cro-Magnon and Neanderthal skulls (e.g. here). I’m personally don’t think that P. atrox skulls are particularly jaguar-like, but vdinets is right in that they’re more like P. spelaea skulls, which also have proportionally wider muzzles. Is it an adaptation to Ice Age conditions (as hypothesized with the Neanderthals), the availability of megafauna on which to dine, or just one of those things?

    Anyway, SDNHM has a nice metal cast of a P. atrox skull on display where you can touch it, and the San Diego Zoo has a cast on a docent table near their lion exhibit, with a lion skull for comparison. Despite its recent bad press in the paleontology community (since resolved), SDNHM is worth visiting if you’re ever in the area.

    Link to this
  37. 37. vdinets 1:37 pm 03/15/2014

    Dartian: in the Sunderbans and elsewhere in India.

    Link to this
  38. 38. Dartian 6:21 am 03/16/2014

    Heteromeles:
    Is it an adaptation to Ice Age conditions (as hypothesized with the Neanderthals), the availability of megafauna on which to dine, or just one of those things?

    AFAWK, the different cranial proportions in the larger taxa may be the result of allometry rather than any strictly adaptive reasons.

    Vlad:
    in the Sunderbans and elsewhere in India

    I tried to google for any specific cases of tigers attacking (and killing?) tourists in open jeeps, but thus far I’ve found none. Even one such attack would be bad news for the local tourism industry (and could hardly be kept secret, especially if the victims were foreign nationals). And you’re claiming that there have been several incidents. Sorry, but I have to insist on more details. When have these attacks taken place and under what circumstances – e.g., were they provoked or unprovoked? Who were the victims – were there fatalities? How many individual tigers have been implicated in these attacks (you were suggesting earlier, in comment #34, that this might even reflect some species-specific behaviour pattern of tigers)?

    Link to this
  39. 39. irenedelse 7:38 am 03/16/2014

    Dartian, Heteromeles:
    I’m curious about this too. IIRC, tigers in the Sundarban do have a history of figuring out human ruses and becoming more dangerous, but so far not to tourists, but to the people who live in the area and have to go into tiger habitat when fishing, wood-gathering, etc. I’m thinking of the time local authorities and tiger conservation people promoted the wearing of masks behind the head when they have to walk through or work in areas where tigers live. The idea was that tigers would not attack if they thought they were watched by a human, and the mask with very visible eyes worn behind the head would fool them. Well, after some time, several tigers figured out that the “eyes behind the head” didn’t really see, and became dangerous to local people again. So the next scheme was to put dummies in the forest, clothed like local people and wearing the famous masks, but fitted with electrified wires that would give a large predator a nasty shock when it tried to munch on them. The rationale: rekindling fear of people in the Sundarban tigers.

    Link to this
  40. 40. DavidMarjanovic 8:12 am 03/16/2014

    tigers have larger brains than lions

    Isn’t that just related to body size?

    Link to this
  41. 41. Heteromeles 9:42 am 03/16/2014

    The only thing I’ve read about the Sundarbans’ tigers was Sy Montgomery’s Spell of the Tiger (looks like she wrote another one, too, The Man-eating Tigers of Sundarbans). It’s a work of journalism rather than science, but it does describe the details of a number of fatal attacks. I read it years ago, so I don’t remember that much, although I seem to remember someone getting pulled out of a boat by a tiger.

    Link to this
  42. 42. Tayo Bethel 4:08 pm 03/16/2014

    The electrified dummy idea is bound to fail sooner rather than later. The reason? Dummies don’t move or act like living creatures. It probably wont take so very long for astute tigers to figure out this latest ruse.
    Isnt brain size also related to habitat complexity?

    Link to this
  43. 43. Yodelling Cyclist 4:43 pm 03/16/2014

    I’d just point out that encephalisation coefficient and what could broadly be called intelligence don’t always correlate.

    Instinct and temperament have a lot to answer for, too. It may well be that Sundarban tigers are “culturally” more adventurous and aggressive than their counterparts in other ecosystems.

    Link to this
  44. 44. vdinets 12:41 am 03/17/2014

    Dartian: that’s really weird: I clearly remember reading something about jeep tours in the Sunderbans being temporarily banned following tiger attacks, but the only thing I can find online is references to one such attack in Rathnambore. Either I am getting false memories, or the story later got suppressed in the media. Give me a couple days, I’ll ask my friends in India if they know anything.

    Link to this
  45. 45. vdinets 12:47 am 03/17/2014

    Yod: sure, that’s possible, too.

    Link to this
  46. 46. naishd 6:37 am 03/17/2014

    FINALLY, I can login again… huh.

    Thanks for continuing comments, looks like others have beaten me to it as goes answers to questions posed above. The ‘lions are skeletally indistinguishable from tigers’ thing is an oft-heard factoid that is absolutely untrue, as indicated by that link above. If you spend any time with the bones of these cats, it’s pretty easy to distinguish them immediately – the whole look of their facial skeletons is highly distinctive in particular, but the rest of their skeletons are species-specific too – tigers have spindlier tail vertebrae and a broader scapula, for example. However, as is typical for mammals with wide ranges and a lot of variation in body size, there’s some overlap in these features.

    And this brings us to Yod’s comment way up-thread (comment # 25): given the overlap seen between the different ‘species clouds’ on the scatterplots, can we reliably differentiate species via morphometrics? Remember that the scatterplot shown above is only one of several we generated: via linear discriminant analysis, we compared different combined sets of measurements in this way, with some combinations producing more robust ‘species clouds’ than others. The overall signal is that, yes, you can be confident about specimens belonging to specific clusters when you have enough data (though there are often outliers, since this is the nature of variation). Our Peruvian specimens were outliers to a degree, but the statistical link to the Jaguar cloud is pretty robust, plus – in any case – they do possess cranial characters unique to Jaguars. Remember that the paper is open access, so more data and discussion is available there if you want to check it out.

    Link to this
  47. 47. Yodelling Cyclist 7:36 am 03/17/2014

    Thanks for the reply and clarification.

    Link to this
  48. 48. CS Shelton 2:35 am 03/18/2014

    Apropos of nothing but I can’t think of a better way to introduce this question to the masters of all Tetrapoda, there’s this article on a website about urban legends…

    http://urbanlegends.about.com/b/2009/05/05/dork-definition.htm

    Which is a response to a widespread belief that “dork” started out as a term for a whale penis. Anyone ever hear of this?

    Are there any animals in which a body part that is homologous to a human part is named differently? Aside from differently specialized homologues like flippers or wings.

    Link to this
  49. 49. DavidMarjanovic 8:19 am 03/18/2014

    Anyone ever hear of this?

    Yes.

    Are there any animals in which a body part that is homologous to a human part is named differently?

    German hunters’ jargon drives this through the roof. The same part has a different name in every species, for starters.

    Link to this
  50. 50. vdinets 1:00 am 03/21/2014

    OK, everybody, I am sorry, but the jeeps attacks story is not true. It was in one of Lonely Planet guides, and, of course, this guidebook series is known for always getting everything they write about nature wrong. There is one tiger in Rathnambore known to chase jeeps, that’s it.

    Link to this
  51. 51. Dartian 6:05 am 03/21/2014

    Vlad: Thanks for clearing that up.

    Link to this

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