Tetrapod Zoology


By complete coincidence – honestly! – we looked yesterday at discovery rates among terrestrial mammals. All indications are that many species remain to be discovered. It should also be well known, and I hope it is, that the same is true for large marine vertebrates: recent discoveries, and extrapolations based on discovery rates, indicate that there are still new, large marine animals to find. Today sees the publication of a new paper by myself and two colleagues, Michael Woodley and Hugh Shanahan, in which we attempt to estimate the number of pinnipeds that might remain undiscovered (pinnipeds are the seals, sea lions, and walruses). And what makes our study unusual is that we then linked this research with an analysis of the cryptozoological literature. How? Why? Who cares? Let’s find out…

New sharks, whales, coelacanths… and seals?

The contention that new, large marine vertebrates await discovery is vindicated by history. The Lesser beaked whale Mesoplodon peruvianus (aka Bandolero beaked whale, or Peruvian beaked whale) is known from specimens discovered between 1975 and 1989, both Perrin’s beaked whale M. perrini and Omura’s whale Balaenoptera omurai were discovered during the late 1970s, the Megamouth shark Megachasma pelagios was discovered in 1976 (and the discovery of a possible second species was announced in 2004), and the Indonesian coelacanth Latimeria menadoensis was discovered in 1998 [image above, showing a merhorse/cadborosaur, long-necked seal and tizheruk to scale with a diver, by Cevdet Kosemen].

A surprising eight pinniped species were named during the 20th century, though most have either turned out to be synonymous with other species, or were actually known long prior to the 20th century. When all of this is taken into account, the most recently named species is the Hawaiian monk seal Monachus schauinslandi Matschie, 1905. If new, large marine vertebrates can still be discovered recently, and if new pinniped species were still being named as recently (comparatively speaking!) as the early 20th century, is it at least possible that new pinnipeds might await discovery?

Are there new pinnipeds to find?


We decided to test this possibility by subjecting the data to statistical analysis. By plotting discovery rates over time, an extrapolation curve can be generated, and estimates can then be made about the species yet to be discovered. Discovery curves typically reach a plateau phase before the likelihood of further discoveries becomes statistically negligible. Several workers have published analyses of this sort before. Paxton (1998, 2001) looked at discovery rates among large, open-water marine animals, Raynal (2001) looked at discovery rates in cetaceans alone, and Solow & Smith (2005) looked at large marine animals in general. These studies all concluded that (at minimum) ten new large marine animals await discovery, with the upper limits from some analyses being 15, 16 or even as high as 50. And what did the pinniped discovery data indicate? Essentially, that there might be a few species yet to find, but that the number is low (Woodley et al. 2009). Note that, while one statistical technique we employed (regression based on a Michaelis-Menten function) suggested the presence of as many as 15 new species, we conclude that this ‘represents a sizable over-estimation of the true numbers remaining to be described’, and it did not match the discovery record as well as other techniques (namely logistic regression) [Fig. 2 from Woodley et al. (2009) shown here. The curve shown was generated following logistic regression].


So, there might be a few pinniped species yet to find. Given that pinnipeds are – generally speaking – large, noisy, obvious animals that use coastlines, it stands to reason that there aren’t going to be lots of undiscovered species. The analytical work is still worth doing however: without it, any extrapolations are conjectural and based on opinion more than analysis [in adjacent image, Michael and I are shown hard at work. Photo by kind courtesy of Dr Mark Witton].

Going that little bit further: the cryptozoological data

Most workers would, probably, have stopped there. We decided to do something different. Michael and I are very interested in cryptozoology and have both published on aquatic cryptids (Naish 1997, 2001, Woodley 2008): that is, on the mysterious aquatic creatures, known almost exclusively from anecdotal accounts, that seem not to match officially recognised taxa. Here I must note that, while it’s inevitable that journalists and commentators will focus on the ‘sea serpent’ aspect of our article, our study is, first and foremost, about the pinniped discovery record.

Anyway, the cryptozoological literature is full of accounts of weird aquatic creatures, and at least some of these animals sound pinniped-like. In fact it has been speculated by some that certain aquatic cryptids might be undiscovered pinnipeds (Oudemans 1892, Heuvelmans 1968, Costello 1974, Mackal 1983, Cornes 2001, Coleman & Huyghe 2003). What’s interesting is that the number of cryptids suggested to be of a pinniped identity is low: as in, around two or three. In other words, the cryptozoological record matches with the extrapolation made from the discovery data. It might seem odd to include a discussion of crypto-pinnipeds in a technical paper, and I know that some people are not going to see this as at all useful. Nevertheless, as we note in the paper, ‘the exclusion of many cryptids from the formal literature has prevented technical appraisal. In turn, this has helped perpetuate a cycle in which these alleged creatures remain predominantly in the ‘grey literature’ and are never really objectively assessed’ (Woodley et al. 2009, p. 5).

i-e249d9144e353e393b8d5a9410a3800f-tizhurek _final_resized.jpg

So, could Heuvelmans’s long-necked sea-serpent, the merhorse, or the tizheruk of the Canadian Arctic [shown here] really be plausible crypto-pinnipeds? If so, these are radically strange beasts, different from known pinnipeds in several respects (size being one notable factor!). On the other hand, their peculiarity relative to other pinnipeds could, hypothetically, explain how they’ve evaded detection for so long: ‘Ultimately, only with the passage of time will the question of whether there remain undescribed pinniped species be resolved, irrespective of how intriguing the evidence’ (Woodley et al. 2009, p. 9).

For previous Tet Zoo articles on aquatic cryptids see…

Refs – –

Coleman, L. & Huyghe, P. 2003. The Field Guide to Lake Monsters, Sea Serpents, and Other Mystery Denizens of the Deep. Tarcher/Penguin, New York.

Cornes, R. 2001. The case for the surreal seal. In Heinselman, C. (ed) Dracontology Special Number 1: Being an Examination of Unknown Aquatic Animals. Craig Heinselman (Francestown, New Hampshire), pp. 39-45.

Costello, P. 1974. In Search of Lake Monsters. Garnstone Press, London.

Heuvelmans, B. 1968. In the Wake of the Sea-Serpents. Hill and Wang, New York.

Mackal, R. 1983. Searching for Hidden Animals: an Inquiry into Zoological Mysteries. Cadogan Books, London.

Naish, D. 1997. Another Caddy carcass? The Cryptozoology Review 2 (1), 26-29.

– . 2001. Sea serpents, seals and coelacanths: an attempt at a holistic approach to the identity of large aquatic cryptids. In Simmons, I. & Quin, M. (eds) Fortean Studies Volume 7. John Brown Publishing (London), pp. 75-94.

Oudemans, C. A. 1892. The Great Sea-Serpent: An Historical and Critical Treatise. Brill, Leiden.

Paxton, C. 1998. A cumulative species description curve for large open water marine animals. Journal of the Marine Biologists Association, U.K. 78, 1389-1391.

– . 2001. Predicting pelagic peculiarities: some thoughts on future discoveries in the open seas. In Heinselman, C. (ed) Dracontology Special Number 1: Being an Examination of Unknown Aquatic Animals. Craig Heinselman (Francestown, New Hampshire), pp. 60-65.

Raynal, M. 2001. Cryptocetology and mathematics: how many cetaceans remain to be discovered? In Heinselman, C. (ed) Dracontology Special Number 1: Being an Examination of Unknown Aquatic Animals. Craig Heinselman (Francestown, New Hampshire), pp. 75-90.

Solow, A. R. & Smith, W. K. 2005. On estimating the number of species from the discovery record, Proceedings of the Royal Society B 272, 285-287.

Woodley, M. A. 2008. In the Wake of Bernard Heuvelmans. CFZ Press, Bideford.

– ., Naish, D. & Shanahan, H. P. 2009. How many extant pinniped species remain to be described? Historical Biology doi:10.1080/08912960902830210


  1. #1 David Marjanović
    March 24, 2009

    Historical Biology… not bad…!

  2. #2 Darren Naish
    March 24, 2009

    Thanks David: we tried Nature, Science and PNAS, but in the end Historical Biology was good enough 🙂

  3. #3 wolfwalker
    March 24, 2009

    Very nice analysis and post, Darren. To some it might not seem like much, but to me it’s an interesting example of applying new tools and thoughts to an old question.

    A thought that occurred to me: your analysis is sound as long as the assumption of pinnipeds as “large, noisy, obvious animals that use coastlines” holds true. If it doesn’t, then the analysis might be badly off.

    I also wonder about the possibility that genetic analysis might reveal that some populations which we think are one species, are in fact two.

    I have no trouble believing there are undiscovered species of whales in the oceans. New species of pelagic birds seem less likely, but still possible.

  4. #4 Naraoia
    March 24, 2009

    I think Paxton has kind of disowned his sea monster discovery curves by now. Or at least the predictions he made from them. IIRC this even came up as an Extrapolation Is Dodgy example in a module he teaches here at St Andrews (though it’s been more than two years since I took that module).

    That guy is quite a character ^_^

    BTW, I’ve been lurking here for a while, and I just wanted to say thanks to Darren and the commenters for the good education. *re-lurks*

  5. #5 Darren Naish
    March 24, 2009

    Michael and I know Charles Paxton well, and we note in our paper that he has indeed toned down his earlier extrapolations (citing pers. comm., we say that ‘more recent study predicts a lower number’ than the 51 or 47 potential new animals postulated in his 1998 and 2001 articles). That’s ok – as discussed above, the lower figures now mooted by some are still plenty exciting enough.

    By the way, isn’t ‘Naraoia’ a trilobite?

  6. #6 Bruce Mohn
    March 24, 2009

    Hi Darren:

    I agree with your statement that finding additional pinniped species at this point is highly unlikely given their terrestrial needs. Has anyone given any thought to the possibility that this cryptid might represent a species that has made the transition to a fully aquatic lifestyle? Presumably that could happen at some point given what we know about the evolutionary history of whales.

    Also wondering if leopard seals might be considered to be longnecked. Do any extant seal/sea lion species lift their heads and necks high out of the water such as the cryptids are claimed to? My experience is limited to harbor seals, which very rarely raised their heads higher than needed to clear their nostrils.

    Thanks for another great post!


  7. #7 Metalraptor
    March 24, 2009

    Excellent post Darren. Although you have to realize, say one of these cryptid pinnipeds is found alive. In that case, it wouldn’t exactly have been a “new” pinniped, because we would have known about it before, it just had not been scientifically described. A catch-22.

    But anyway, one might wonder if all of these “late-surviving plesosaur” sightings are really those of another derived lineage of pinnipeds, maybe something distantly related to Acrophoca or Enaliarctos. Some of the traits of these animals, if the reports are to be believed, show behaviors that Late Cretaceous plesiosaurs appear not to have had, such as the ability to come onto land and the ability to hold their neck swan-like out of the water. Of course, then again, whose to say that evolution hasn’t happened in the past 65 million years these animals were absent from the fossil record, if they are plesiosaurs. Perhaps adaptations to return, at least temporarily, to land and to hold one’s head swan-like out of the water are adaptations towards a generalist lifestyle, in order to compete with whales, seals, and such.

  8. #8 Metalraptor
    March 24, 2009

    “large, noisy, obvious animals that use coastlines”

    Perhaps more primitive seals were not noisy, gregarious animals, or perhaps this is a group that has made a full transistion to the water, as Bruce stated above.

  9. #9 Jerzy
    March 24, 2009

    Just my post got eaten 🙁

    Very overfed Cadborosaurus and optical size distortion over water explains records of sea lions.

    But I would advocate doing DNA research on all bone specimens in S Pacific museums. There can really be undiscovered cetaceans. But to believe, I need proper DNA research showing species-level divergence.

  10. #10 David Marjanović
    March 24, 2009

    isn’t ‘Naraoia’ a trilobite?

    No, it’s another sort of Cambrian arthropod.

  11. #11 Jerzy
    March 24, 2009


    BTW – can I open-access it using doi?

  12. #12 David Marjanović
    March 24, 2009

    I need proper DNA research showing species-level divergence.

    So suddenly you’re advocating a phenetic species concept?

  13. #13 Matt Bille
    March 24, 2009

    To Darren, et. al.,

    This looks like superb work. It may, and hopefully will, prove to be a major advance in finding and identifying “sea serpent” species.

    Loren Coleman on Cryptomundo suggested there may be only two species of pinniped involved, with age and sex accounting for the variations in the largest species. I’m curious what you think of that.
    I still think another animal that could be “out there” is a huge eel, and I’m interested in whether you believe this might possibly be “swapped” for one of the pinnipeds.

    Two additional tidbits, which you probably know, but I’ll offer them up:

    Dr. Bruce Robison of MBARI said at least a third of the “large animals” (he didn’t define the term) in the oceans were unidentified, and that may be conservative – “it could be half.”

    When I was writing Shadows of Existence (2006), I corresponded with James Mead and other leading researchers on beaked whales. They were unanimous in believing there were still undescribed species in Mesoplodon or a related genus, so you have solid scientific opinion in favor of some large marine mammals yet to be classified. I know Darren is an expert on this, but I’ll throw in the notion that, while beaked whales are, as a rule, harder to find than pinnipeds, in both cases you have good sighting reports to indicate new species. Given that most beaked whales have only been pinned down taxonomically after skulls or carcasses were discovered, it seems likely that a thorough examination of museum collections of pinniped skulls (a hugely manpower-intensive effort, to be sure) would turn up something.
    Again, congratulations to all the authors on an excellent contribution.

  14. #14 David Marjanović
    March 24, 2009

    …blockquote fail… the second line is mine.

  15. #15 anon
    March 24, 2009

    Bruce Mohn posted:

    “Do any extant seal/sea lion species lift their heads and necks high out of the water such as the cryptids are claimed to?”

    — A few photos of (not-very-long-necked) pinnipeds “periscoping” (mixed in with photos of submarines and stuff).


    Harbor Seal (Phoca vitulina) periscoping


    I *think* I’ve seen photos of Leopard Seal (Hydrurga) doing this, but haven’t found any online yet.

  16. #16 Erik Knatterud
    March 24, 2009

    A very interesting article. I got no problem whatsoever that some 15 plus new species of cetaceans or pinnipeds may yet be discovered in the seas. I have studied Norwegian sea serpents from our fjords, rivers and lakes for some time and have nearly finished a book manuscript of said animals. My analysis have revealed some very remarkable qualities that enable them to survive in such harsh environments with ice covers lasting months and freezing temperatures for the remainder of the year. Moreover, I have come to doubt very much that sea serpents really are mammals as most researchers do claim, but rather of reptilian origin. To verify that, one obviously has to be caught.
    I have seen them, they do exist.
    P.s. Sture the Stork is back at his favourite lamp post!

  17. #17 thylacine
    March 24, 2009

    And the water horse would fit in where?

  18. #18 Raymond Minton
    March 24, 2009

    Sea monsters are certainly more likely than lake monsters, for a variety of reasons, and I certainly want to hear more about this.

  19. #19 Loren Coleman
    March 24, 2009

    My sincere congratulations to Darren Naish, Michael Woodley and Hugh Shanahan. This is a milestone paper. At midnight in America on Cryptomundo, I mentioned this has been a greatly anticipated paper. Also, I penned this nod to them: “Cryptozoology can now come out of the cold water.”

    Being a long-term member (since before Heuvelmans’ In the Wake… book reached me in 1965) of the pinniped school as the source for some of the more dramatic reports of “Sea Serpents,” I think Darren knows my concerns about Merhorses & Long Necks are minor compared to my overall sense they are out there! I merely find the evidence for a combined new species, the Waterhorse, makes more sense.

    But hey, I bet Darren Naish, Michael Woodley, Hugh Shanahan, and I would all agree that to find one new pinniped species in a marine or freshwater environment that is a match for the records from cryptozoology would be a remarkable discovery, indeed!

  20. #20 220mya
    March 24, 2009

    I can’t seem to find the article on the Historical Biology Informaworld website. The DOI Darren provided (10.1080/08912960902830210) also doesn’t seem to work. Anyone else having this problem?

  21. #21 Jerzy
    March 24, 2009

    Well I thought it could be 1 April joke, but even bright Darren is not THAT far before everybody else?

    Or do we see Fools Day leaking around, no doubt because of certain qualities of members of Parlament?

  22. #22 William D. Robertson
    March 24, 2009

    This sounds like an interesting paper, which hopefully I will be able to read in full sometime. One question that springs to mind is whether the paper considers the reproductive biology of these putative pinnipeds. There are cryptozoological reports of people finding tiny baby Cadborosauri in coastal areas of the Pacific Northwest. If these reports are true, that would cast some doubt on a pinniped identification for these (supposed) animals, as producing and abandoning very small offspring seems a non-mammalian breeding strategy.

  23. #23 Cameron
    March 24, 2009


    I’m nearly convinced that the illustration from the story is a poorly-drawn pipefish.

    Also, how cool is that monsterous, green, leopard seal-like pinniped drawn by Nemo Ramjet?

  24. #24 Erik Knatterud
    March 24, 2009

    Merhorses, waterhorses or long necked seals won’t fit at all, since these are mammals. Having studied our indigenous sea serpents, “sea monsters” and “lake monsters” are but one species, except the lake creatures are easier to study since they are in a confined area. I have not used foreign sea serpents or creatures from the high seas, except a few examples of comparisons when baby monsters are concerned. You will have to wait for the book about our fjord monsters till early autumn supposed I can get somebody interested in publishing it, hopefully in digestable English.
    Sorry Darren, for marketing my upcoming book this way. Won’t happen again.

  25. #25 Metalraptor
    March 24, 2009

    I would probably say that if these creatures do exist, they may just be variations of different species within the same genus, the differences between individuals in sightings attributed to age, gender, location (think subspecies) or species. These animals may have taken a niche similar to long-necked plesiosaurs in the Mesozoic, which has remained curiously somewhat unoccupied throughout the Cenozoic (as in, that of a long-necked piscivore).

    I have also heard from sources that perhaps these “sea serpents” and “lake serpents” are instead highly derived temnospondyls, possibly Koolasuchus derived. Or, if they perhaps came from Antarctica and then later became pelagic there, it would explain why so no fossils of them have been found as of yet. But I am still surprised as to why no one has attempted to follow up on one of the more obvious ideas: that sea serpents are archaeocetes of some kind, perhaps a third lineage of whale that survived the extinction of their other kin with the odontocetes and mysticetes by becoming somewhat plesiosaur-like.

    However, I feel we may be taking this study a bit too far (though it is fun). The study above suggested that there could be more large marine mammal or tetrapod genera out there that we don’t know about, which means that these long-necked plesiosaur mimics (or in some suggested cases, plesiosaurs themselves) could be out there, but it doesn’t guarantee it. For all we know, the genera that are out there could be even stranger. Nature doesn’t always like to follow our rules. A giant flying manta ray that eats people? Maybe….

  26. #26 Carlos
    March 24, 2009

    And what about the bloop? 😛

  27. #27 Cameron
    March 24, 2009

    I have also heard from sources that perhaps these “sea serpents” and “lake serpents” are instead highly derived temnospondyls

    No, they’re clearly pachypleurosaurs. Seriously though, what trait could temnospondyls possibly have that makes them a more likely candidate for sea serpent sightings than any other group of aquatic tetrapods? I really need to come up with a term for the apparently random selection of proposed cryptid identities…

    that sea serpents are archaeocetes of some kind

    Now that we know a little more about cetacean evolution, somehow archaeocetes looking like giant otters, strings of buoys, and giant centipedes don’t look very plausible.

  28. #28 Morgan Churchill
    March 25, 2009

    brand spanking new species of pinniped wouldn’t be impossible; known species have been overhunted and subsequently declared extinct, only to be rediscovered. I would say though any completely new species would more likely be a phocid, as they are much less gregarious than otariids or odobenids.

    What I would expect though is more likely is the recognition of known populations as distinct species. Some of the freshwater populations of Harbor and Ringed Seals in particular seem to be morphologically and genetically distinct, and I question whether the Atlantic and Pacific populations of Walrus should be really treated as one species.

    Also, rediscovery of a surviving population of Japanese Sea Lion would be great…they are believed to be extinct, but I think recently an effort was made to look for them somewhere around Korea. This used to be considered a subspecies of California Sea Lion, but recent genetic studies have advocated splitting this and the Galapagos population off as separate species.

  29. #29 Checkmate
    March 25, 2009

    I searched for “tizhurek” on Google and I found almost nothing. Instead, I was given recipes for “Zurek,” a type of soup.

  30. #30 Loren Coleman
    March 25, 2009

    Of course, we must remember that Native terms for cryptids, folkloric beings, and twice-told creatures exist outside of Google, in oral traditions and printed books.

    But if one is looking up tizhurek alone, they would get frustrated quickly.

    The alternative spelling, tizheruk, would eventually reward the Google-seeker with even a Wikipedia passage.

  31. #31 Darren Naish
    March 25, 2009

    Sorry – ‘tizhurek’ used above was a typo, and in the paper we refer to it as ‘tizheruk’. I’ll go correct this.

  32. #32 Jerzy
    March 25, 2009

    Cryptozoological animals, naturally, only require cryptic names and cryptic papers. 😉

    BTW, I have terrific idea to find sea cryptid by looking for washed-up carcasses on remote pacific coasts. Any idea who can finance my holiday to Alaska?

  33. #33 Dartian
    March 25, 2009


    the most recently named [pinniped] species is the Hawaiian monk seal Monachus schauinslandi Matschie, 1905.

    Any particular reason why it wasn’t named much earlier? The seals were, after all, known – and even hunted – by Westerners well before that (e.g., Svihla, 1959). Did people think that the Hawaiian monk seal was conspecific with some already described seal species?


    Svihla, A. 1959. Notes on the Hawaiian monk seal. Journal of Mammalogy 40, 226-229.

  34. #34 Mark Lees
    March 25, 2009

    Excellent post. I hope to get to read the article sometime.

    While it is important to approach claims relating to ‘cryptids’ with a reasonable measure of scepticism, there does seem to be substantial body of evidence for the existence of some of them. I was very impressed by the sheer volume of evidence presented in O’Neill’s ‘The Great New England Sea Serpent’ – it certainly seems to me that something was going on from the late 18th to the early 20th Centuries off the Atlantic coasts of the northern USA and Canada, and it’s hard to see how this could be attributed to any recognised species. I think that Oudemans, Huevelmans and Sanderson all suggested that it may have been a zeuglodon (Archaecete) – though Oudemans seems to have changed his ideas later.

    Personally I think that a giant pinniped is less plausible than an archaecete for the large sea serpents. I know that Darren has previously commented on the large gap in the fossil record of archaecetes as an argument against them as potential explanations for sea serpents, but which is the more likely, the continued existence of creatures for which there is a long gap in the fossil record, or the existence of a creature for which there is no fossil record?

    On the subject of the archaecete fossil record, this reminded me that a few years ago when doing a bit of personal research I came across two references to fossils attributed to an archaecete genus (I can’t recall which) being found in Pliocene/Lower Pleistocene deposits. I’m afraid I don’t have the references to hand, but I recall they were vague and when I attempted to find more information I drew a blank. I assume that these were based on a mistake (either a typo or misdating) or else where reworked, but I’d be intrigued to know if anyone else has any more info on it.

    Also with reguard to archaecetes, as far as I can establish protocetids and remingtonocetids lacked tail flukes (they lack key features in their tail structure) while the likes of Basilosaurus and Dorudon (the traditional archaecetes) had them. This would have had significant impact on their biology – while Dorudon could have swam like a modern whale, protocetids clearly could not. Personally I would like to see the term archaecete restricted to the forms like Basilosaurus and Dorudon, with another term used for the fluke-less forms. I stongly suspect that if they existed today we would think of the likes of Dorudon as whales, while protocetids would be very dfferent animals.

    Anyway, back on topic. Darren congratulations to you and you coauthors on you publication. I look forward to next big marine mammal discovery, and hope it warrants at least a new genus.

  35. #35 Darren Naish
    March 25, 2009

    Dartian asked about the delay in the scientific discovery of the Hawaiian monk seal. Good question…

    The Hawaiian monk seal was actually discovered pretty late: it’s usually stated that Yuri Lisianski, the Russian explorer, was first to bring attention to them in 1805. For the next 90-odd years, it seems that everyone who knew about them assumed that the Hawaiian seals were ‘just seals’. In 1896-7, Hugo H. Schauinsland stayed at Laysan, and here he collected seal material and later sent it on to Berlin. Here it came to the attention of Paul Matschie: this was the first time the Hawaiian seal had been looked at by anyone with the means to study it properly. It was clearly a new species, most similar to the monk seals of the Mediterranean and Caribbean, and hence Matschie published his description, with the new name Monachus schauinslandi, in 1905.

    Peter J. H. van Bree wrote an article on this subject in 2002, available here.

  36. #36 Naraoia
    March 25, 2009

    By the way, isn’t ‘Naraoia’ a trilobite?

    It’s great to be in a place where people know it’s not someone’s fantasy character ^_^

    I think it was thought to be a trilobite, but it no longer is. I haven’t really looked, other than checking it at trilobites.info.

    Whatever it is, it has a cool name.

  37. #37 Andreas Johansson
    March 25, 2009

    Near as I can tell, Naraoia is either a basal trilobite or a relative of the trilobites. The answer may depend on how wide your definition of Trilobita is.

  38. #38 Jerzy
    March 25, 2009

    I think Galapagos sea lion was recognized later (Sivertsen, 1953), earlier was misclassified as Patagonian sealion.

    BTW, this blog turned into long discussions. Anybody knows some serious zoological forum?

  39. #39 David Marjanović
    March 25, 2009

    Personally I would like to see the term archaecete restricted to the forms like Basilosaurus and Dorudon

    The term “archaeocete” seems to have already been widely abandoned simply for being paraphyletic. The smaller paraphyletic group you’re talking about is best described as “non-neocetan pelagicetes” according to the title-page paper of the September issue of JVP.

  40. #40 Dr Vector
    March 25, 2009

    I really need to come up with a term for the apparently random selection of proposed cryptid identities…

    True dat. Darren has coined PSP for the Prehistoric Survivor Paradigm; the only problems with this are (1) inevitable turf war with Postcranial Skeletal Pneumaticity, and (2) it’s not exactly what you’re talking about.

    How about Phylogenetic Roulette for Identifying Cryptids? Modesty prevents me from pointing out the aptness of the resulting acronym.

  41. #41 Cameron
    March 25, 2009

    Phylogenetic Roulette for Identifying Cryptids?

    I love it! Now to write a post ranting/whining about its most heinous uses…

  42. #42 Jerzy
    March 25, 2009

    Not exactly this, but.

    What about Cool Megamonsters in analogy of charismatic megavertebrates?

  43. #43 Jude
    March 26, 2009

    Congratulations on publication, but species discovery curves became obsolete a couple of years ago.

    Bebber et al in “Predicting unknown species numbers using discovery curves” (2007) conclude that “…using discovery curves for incomplete groups is largely futile.”

    Their reasoning: “There are many reasons why species continue to be described for many taxa such as the use of new analytical techniques, new species concepts, new areas of the world being explored, publication of a long-term monographic study, etc. Thus, even for apparently completed curves, it only takes effort in any one of these variables to discover new species.”

    The authors go on to “…suggest that biologists shift focus from species discovery curves to other methods…that are immune to the problems caused by temporal variations in the discovery process.”

  44. #44 Darren Naish
    March 26, 2009

    The paper being referred to is…

    Bebber, D. P, Marriott, F. H. C, Gaston, K. J, Harris, S. A, Scotland, R. W. 2007. Predicting unknown species numbers using discovery curves. Proceedings of the Royal Society B: Biological Sciences 274, 1651-1658.

    While, indeed, the authors note that species discovery curves may well produce estimates that are way off for many groups, they said that this is less likely to be the case when ‘the inventory of a group is nearly complete’. For such groups as pinnipeds, cetaceans, and perhaps even large marine vertebrates in general, therefore, the endeavour seems not to be futile. They were mostly cautioning about applying discovery curves to such things as birds, mosses, gymnosperms, etc., and not to small groups of, say, less than 100 species.

    I wonder what this means for the Mesozoic dinosaur extrapolation curves?

  45. #45 Dartian
    March 26, 2009


    For such groups as pinnipeds, cetaceans, and perhaps even large marine vertebrates in general, therefore, the endeavour seems not to be futile.

    At least the discovery of new species of elasmobranchs, which surely qualify as ‘large marine vertebrates’, is still very much ongoing.

  46. #46 Jude
    March 27, 2009

    “…this is less likely to be the case when ‘the inventory of a group is nearly complete’.”

    But then you end up begging the question. You’ve already concluded that the inventory of pinnipeds is nearly complete (“there might be a few pinniped species yet to find”). Now, in order for species discovery curves to be useful, you have to assume that the inventory of pinnipeds is nearly complete. Your conclusion becomes a premise in your argument.

  47. #47 Darren Naish
    March 27, 2009

    But what I said about the pinniped inventory being nearly complete isn’t an assumption: it’s a conclusion based on pretty good evidence.

  48. #48 Titanis walleri
    March 28, 2009

    “A giant flying manta ray that eats people? Maybe….”
    So I’m not the only one who’s read Natural Selection

  49. #49 Tim Morris
    March 28, 2009

    Firstly I’d like to second the idea that the Sea-serpent-seal might have evolved to become fully aquatic, giving birth in water.

    And secondly, why hasn’t anyone mentioned steller’s sea-ape?

  50. #50 David Marjanović
    March 28, 2009

    I wonder what this means for the Mesozoic dinosaur extrapolation curves?

    Not much, because those curves are barely reaching what looks like a long vertical part.

  51. #51 bose headphones
    July 20, 2009

    I like very much the writings and pictures and explanations in your adress so I look forward to see your next writings.

    [from Darren: wow, new spam. Have deleted the url.]

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