Feresa: The Growling Wolf-Dolphin

The dolphin Feresa attenuata has been bestowed with dreadfully stupid common names. Feresa has been recognized as distinct from Orca since Gray (1871), which makes "Pygmy Killer Whale" both inappropriate and archaic. The alternative "Slender Blackfish" is actively misleading as the superficially similar Pseudorca is more slender (Reeves et al. 2002) and well-lit color photographs in Rossi-Santos et al. (2006) show that the species is actually brown, contra every illustration. I'll be calling the dolphin "Feresa" from here on out (I'm also not too fond of  "attenuata") as my alternate suggestion in the title is a tad verbose.

Feresea... maybe. This species can be distinguished from Pseudorca by having a proportionally larger dorsal fin (2 base lengths away from the blowhole vs. 2.5) and by having a clearly demarcated cape; Peponocephala can be distinguished by having pointed flipper tips, a pointed head when viewed from above, and no white extending around the face (Baird 2010). I think this is the case in the above photo, but I'm not entirely certain. Photo by Gary L. Friedrichsen from WoRMS.

Feresa is one of the most poorly-known toothed whales (McSweeney et al. 2009) and single sightings or strandings are still viewed as deserving publication (Baird 2010). Prior to 1954, the species was known from only two skulls (Reeves et al. 2002), making it extremely poorly-known even compared to beaked whales. What makes this absolutely shocking is that Feresa is not a cryptic species. They are known from the tropics and subtropics worldwide, are easy to detect in visual surveys, do not take extended dives, and (contra Leatherwood et al. 1982) do not avoid vessels (McSweeney et al. 2009). While their surface behavior is normally subdued compared to other dolphins, they have been observed jumping high above the surface and even riding on bow waves (Reeves et al. 2002). It appears that while a deep-water habitat and confusion with Pseudorca and Peponocephala can explain the lack of observations to a degree, the main factor is probably the species being rare (McSweeney et al. 2009).

In 1965 - a little over a decade after the external appearance of the animal became known - Feresa was held in captivity. Pryor (1991) remarked that one individual behaved "more like a wolf than a normal dolphin" would "growl and snap like as canid" and "not hesitate to attack people and other cetaceans". Since when are cetaceans capable of growling? This behavior has led some to presume that Feresa preys on mammals in the wild (Leatherwood et al. 1982) and aggression towards other dolphins has been observed whilst individuals were trapped in tuna seines (Reeves et al. 2002). Considering that both situations occurred in cramped and undoubtedly stressful environments, I think it is completely unfounded to conclude that Feresa is a pugnacious marine mammal-killing macropredator with the available evidence. Stomach contents have included squid and fish (Rodríguez-López and Mignucci- Giannoni 1999; Zerbini & Santos 1997)

Feresa skeleton. From Wikipedia Commons.

The skeleton of Feresa does appear superficially Orca-like, however, it is not a particularly close relative, hence my strong dislike of the "Pygmy Killer Whale". There is some disagreement as to how closely they are related; Slater et al. (2010) places Orcinus (and Orcaella) as the most basal delphinids, however Vilstrup et al. (2011) consider both to be both members of the clade Globicephalinae, but with Orca as the most basal member and Feresa as a derived member and close relative of Peponocephala and Globicephala. This seems like a very interesting group, and perhaps I'll give it some more coverage.


References:

Baird, R. W. (2010). Pygmy Killer Whales (Feresa attenuata) or False Killer Whales (Pseudorca crassidens) Identification of a Group of Small Cetaceans Seen off Ecuador in 2003. Aquatic Mammals 36(3), 326-327. Available.

Gray, J. E. (1871). Supplement to the Catalogue of seals and whales in the British Museum. Available.

Leatherwood, S., Reeves, R. R., Perrin, W. F., & Evans, W. (1982). Whales, dolphins, and porpoises of the eastern north pacific and adjacent arctic waters (NOAA Technical Report NMFA Circular 444). Washington, DC: U.S. Department of Commerce, National Oceanic and Atmospheric Administration, National Marine Fisheries Service. Partially Available.

McSweeney, D. J., Baird, R. W., Mahaffy, S. D., Webster, D. L., and Schorr, G. S. (2009). Site fidelity and association patterns of a rare species: Pygmy killer whales (Feresa attenuata) in the main Hawaiian Island. Marine Mammal Science 25(3), 557-572. Available.

Pryor, K. (1991). Mortal remains: Studying dead animals. In: Pryor, K. & Norris, K. S. (eds.) Dolphin Society: Discoveries and Puzzles. University of California Press: Berkeley. Available.

Reeves, R. R., Stewart, B. S., Clapham, P. J., & Powell, J. A. (2002). National Audubon Society Guide to Marine Mammals of the World. Alfred A. Knopf: New York.

Rodríguez-López, M. A. & Mignucci-Giannoni, A. A. (1999). A stranded pygmy killer whale (Feresa attenuata) in Puerto Rico. Aquatic Mammals 25(2), 119-121. Available.

Rossi-Santos, M., Baracho, C., Neto, E. S., & Marcovaldi, E. (2006). First sightings of the pygmy killer whale, Feresa attenuata, for the Brazilian coast. JMBA2 - Biodiversity Records. Available.

Slater, G. J., Price, S. A., Santini, F., and Alfaro, M. E. (2010). Diversity versus disparity and the radiation of modern cetaceans. Proceedings of the Royal Society B 277(1697), 3097-3104. Available.

Vilstrup, J. T., Ho, S. Y. W., Foote, A. D., Morin, P. A., Kreb, D., Krützen, M., Parra, G. J., Robertson, K. M., de Stephanis, R., Verborgh, P., Willerslev, E., Orlando, L., & Gilbert, M. T. P. (2011). Mitogenomic phylogenetic analyses of the Delphinidae with an emphasis on the Globicephalinae. BMC Evolutionary Biology 11(65). Available.

Zerbini, A. N. & Santos, M. C. O. (1997). First record of the pygmy killer whale Feresa attenuata (Gray, 1874) for the Brazilian coast. Aquatic Mammals 23(2), 105-109. Available.

Eocetus, "Eocetus", and Friends

Update (January 28, 2014): "Eocetus" wardii is now Basilotritus wardii. More on my new post, The Third King.


I was shocked that Uhen (2010) remarked that Basilosaurus drazindai and Basiloterus hussaini "probably represent protocetids... akin to Eocetus". This would place the whales outside Pelagiceti and imply that the now-questionable basilosaurids were potentially capable of walking on land, despite being enormous. Unfortunately, other mentions of this revised placement give no further details (Uhen 2008, Uhen et al. 2011) and Uhen (2010) further states the placement is "difficult to determine with certainty" due to scarce materials. I suspect the hypothesis will not be officially discussed until further material is found and/or described... which won't stop me from wildly speculating.

Lumbar vertebrae in right lateral view. From left to right: "Eocetus" wardii (from Uhen 1999), Basiloterus hussaini, and Basilosaurus drazindai - note that the latter-most may be an anterior caudal (from Gingerich et al. 1997). For comparison: Basilosaurus isis vertebrae.

In the description of Basilosaurus drazindai, Gingerich et al. (1997) note a number of "primitive retentions" which resemble the morphology of "generalized archaeocetes": long neural spine and arch; broad, almost-horizontally placed, anterior-projecting metapophyses which project beyond the anterior edge of the vertebral centrum; and paired, posterolateral processes of the neural arch. Aside from the last trait (which I can't confirm without a dorsal view), all of these traits are present in "Eocetus" (Uhen 1999). Additionally, "Eocetus" has elongated transverse processes, unlike the condition of Basilosaurus (Uhen 1999); however, B. drazindai has processes with a 15.5 cm long base (they broke off) relative to the 30 cm centrum (Gingerich et al. 1997), and so probably had a similar, albeit slightly less extreme, condition. The only criterion for placing B. drazindai in the genus Basilosaurus was the size and shape of the centrum (Gingerich et al. 1997), and while they are uncannily similar in shape, everything else seems to be pointing towards a relationship with "Eocetus".

Lumbar vertebrae in anterior view. Ditto order.

As for awkward middle-child Basiloterus, it appears to have a centrum which is slightly more elongated than that of "Eocetus", however the neural arch and maybe the neural spine appear to be narrower. The metapophyses are upwardly-angled (Gingerich et al. 1997), less broad, less anterior-projecting, but still appear to extend past the centrum. The posterolateral processes are absent (Gingerich et al. 1997). The base of the transverse process is 9.3 cm long relative to a 19.5-20 cm centra (Gingerich et al. 1997), proportionally similar to Basilosaurus drazindai. The placement of Basiloterus is thus not clear, and perhaps it was a basilosaurid or an even more derived protocetid.

Maiacetus inuus, a basal "protocetid" (Uhen 2011). From Wikipedia Commons.

Protocetidae is a blatantly paraphyletic "family" of extinct cetaceans from Eocene coastal marine deposits with hip and femur morphology indicating amphibious capabilities (most of the time) and no evidence of flukes (Uhen 2010). Uhen (1999) appears to think that "Eocetus" wardii had weight-bearing hips, however Uhen (2010) refers to them as "moderately reduced" and regarded the species as possibly non-amphibious. This is perhaps not surprising since Eocetus, "Eocetus", and an unnamed Pisco Formation species are the sister group of Pelagiceti (Uhen et al. 2011). This could make them closer relatives of Dorudon than Maiacetus, and raises the question of how many typical protocetid traits they actually exhibited. Perhaps they were entirely aquatic tail-based swimmers which just happened to have fairly large vestigial legs.

Dorudon atrox. From Wikipedia Commons.

The scare quotes around "Eocetus" hint at a taxonomic misadventure. "E." wardii was assigned to its genus by Uhen (1999) based on comparisons of its skull and vertebrae to Eocetus schweinfurthi; the problem is, the holotype of E. schweinfurthi is an isolated skull and it is not possible to determine whether the vertebrae referred to it actually represent the species (Geisler et al. 2005). There is overlapping skull material (Uhen 1999), but Geisler et al. (2005) apparently regarded it as too incomplete to warrant unambiguous placement in the genus. Somehow, "Eocetus" and Eocetus formed a clade in phylogenetic analyses (Geisler et al. 2005, Uhen et al. 2011), making it probable that future discoveries will confirm their close relationship.

"Eocetus" wardii is clearly related to unnamed Pisco Formation material which exhibits the same distinctive traits (moderate centrum elongation, elongated neural arches and spines and transverse processes, strange pock-marked texture) with the only difference being that the unnamed material is 35% smaller (Uhen et al. 2011). The Egyptian vertebrae dubiously assigned to Eocetus schweinfurthi (figured in Uhen 1999) also seem quite similar (including the pock-marks), and if it is also a member of this clade, it would indicate a sizable trans-oceanic range. This in turn could be taken as evidence of the whales being largely pelagic... of course this is quite speculative.

There of course remains much to be known about these cetaceans, and perhaps future discoveries will be enlightening as to how similar they were to the pelagic cetaceans, as well as the origins of Pelagiceti. I really hope it turns out that a Basilosaurus-sized animal could walk on land.


References:

Geisler, J. H., Sanders, A. E., and Luo, Z-X. (2005). A New Protocetid Whale (Cetacea: Archaeoceti) from the Late Middle Eocene of South Carolina. American Museum Novitates 3480, 1-65. Available.

Gingerich, P. D., Arif, M., Bhatti, M. A., Anwar, M., & Sanders, W. J. (1997). Basilosaurus drazindai and Basiloterus hussaini, new Archaeoceti (Mammalia, Cetacea) from the middle Eocene Drazinda Formation, with a revised interpretation of ages of whale-bearing strata in the Kirthar Group of the Sulaiman Range, Punjab (Pakistan). Contributions from the Museum of Paleontology, University of Michigan 30 (2), 55-81. Available.

Uhen, M. D., Pyenson, N. D., Devries, T. J., Urbina, M., and Renne, P. R. (2011). New middle Eocene whales from the Pisco Basin of Peru. Journal of Paleontology 85(5), 955-969. doi: http://dx.doi.org/10.1666/10-162.1

Uhen, M. D. (2010). The Origin(s) of Whales. Annual Review of Earth and Planetary Sciences 38, 189–221. Available.

Uhen, M. D. (2008). Basilosaurids. In: Perrin, W. F., Würsig, B., and Thewissen, J. G. M. (eds.) Encyclopedia of Marine Mammals, Second Edition. Elsevier: Burlington, Massachusetts. Available.

Uhen, M. D. (1999). New Species of Protocetid Archaeocete Whale, Eocetus wardii (Mammalia: Cetacea) from the Middle Eocene of North Carolina. Journal of Paleontology 73(3), 512-528.

Weems, R. E., Edwards, L. E., Osborne, J. E., and Alford, A. A. (2011). An occurrence of the protocetid whale "Eocetus" wardii in the Middle Eocene formation of Virginia. Journal of Paleontology 85(2), 271-278. Available.

Picture of the Indiscriminate Interval #000008 - Eurhinodelphis longirostris

Eurhinodelphis longirostris at the American Museum of Natural History.

The most striking trait of Eurhinodelphidae is a toothless extension of the rostrum beyond the mandible (Lambert 2005), superficially similar to the bills of Billfish and Swordfish. Oddly, this morphology was speculative for a period of time (Kellogg 1925) although it has apparently been confirmed in several species as of Lambert (2005). Unfortunately, information on eurhinodelphids is scant and/or difficult to access and, among numerous other basics of their biology, I really don't know what the function of the extended rostrum would be. The only suggestion I could find is from one professor Abel who speculated that the cetaceans "swam on the surface of the sea, where they captured food - probably fishes - in much the same manner as does the skimmer (Rhynchops) [sic] among birds" (Anonymous 1909). Somehow, I find this even less plausible than azhdarchids-as-skimmers. On a curious note, there is a cetacean with the reverse of eurhinodelphid morphology (mandible extending past rostrum) unofficially known as the... skimmer porpoise.

Phylogenetically, eurhinodelphids have bounced around from being considered stem-ziphiids, the sister group to Delphinida, and the sister group to Squalodontidae + Squalodelphidae (Geisler et al. 2011 - citing various); within Geisler et al. (2011), they were placed outside crown-Odontoceti¹ in an unconstrained analysis and as the sister group of platanistoids in a constrained analysis. The authors regarded the latter position as more probable and placed eurhinodelphids within the new group Synrhina, which includes most odontocetes except for Sperm Whales and assorted extinct taxa. Whatever their placement, eurhinodelphids are certainly close relatives of living toothed whales, despite that whole extinct thing.

¹ It actually states they "did not fall inside crown Cetacea", but this is a typo. Otherwise, they'd be Miocene Archaeocetes. 

Eurhinodelphis longirostris seems to have an unusually long neck for a cetacean. The cervical vertebrae are not fused (Kellogg 1925), however this is a surprisingly common trait shared with river dolphins, monodontids, rorquals, and gray whales (Tinker 1988). The neck of E. longirostris appears to be proportionally longer than those of the baleen whales and Narwhal and is probably comparable to those of the Beluga and Dorudon. River dolphin skeletons are hard to find, but it seems likely they have similarly proportioned necks. It seems that Eurhinodelphis wasn't a total freak, well, except for the snout.

The Theatrical Tanystropheus covered Eurhinodelphis as well, and it doesn't even overlap that much!

References:

Anonymous. (1909). Notes. Nature 2088 (82), 16. Available.

Geisler, J. H., McGowen, M. R., Yang, G., Gatesy, J. (2011). A supermatrix analysis of genomic, morphological, and paleontological data from crown Cetacea. BMC Evolutionary Biology 11 (112). Available.

Kellogg, R. (1925). On the occurrence of fossil porpoises of the genus Eurhinodelphis in North America. Proceedings of the U. S. National Museum 66(26), 1-40. Available.

Lambert, O. (2005). Les dauphins longirostres et les baleines à bec du Néogène de la région d’Anvers: systématique, phylogénie, paléo-écologie et paléo-biogéographie. Doctoral Thesis. Partially Available.

Tinker, S. W. (1988). Whales of the World. E. J. Brill Publishing Company: New York. Partially Available.

Picture of the Indiscriminate Interval #000007 - Narwhal

Monodon monoceros at the American Museum of Natural History.

Narwhals are a bit strange even by cetacean standards. I'll let the title of this Tet Zoo article speak for itself: "A 3-m tooth that can bend 30 cm in any direction and is hypersentitive to salinity, temperature and pressure... and the sonic lance hypothesis".

They get weirder. Without the tooth (or sometimes, teeth) it is difficult to picture how this flat-skulled cetacean could be the same as a bulbous-headed Narwhal. As brought up in my Dorudon post, there are colossal amounts of soft tissue involved.

Another soft-tissue feature not hinted at by the skeleton are unusually shaped flukes... in males. Fontanella et al. (2010) suggest that the concave leading edge and lack of sweepback of the flukes increases lift and thrust to compensate for the drag caused by the tusk in males. The implications of the occasional tusked female narwhal were not discussed by the authors.

One female Narwhal was estimated to be 114.8 (± 10.2) years old (Garde et al. 2007) which, if correct, would make Narwhals the third oldest known mammals after humans (122 years) and Bowhead Whales (211 years?). Garde et al. (2007) used a sample of 75 individuals (15 juvenile) from a heavily hunted population, and subsequently speculated that Narwhals in other populations could potentially reach "considerably higher" ages. As for methodology, Garde et al. (2007) used aspartic acid racemization rate in the eye; this method was also used to calculate the extreme age estimate for Bowheads (George et al. 1999), and ages of over a hundred years have subsequently been supported by bomb lance fragments (George and Bockstoce 2008) and ovarian corpora counts (George et al. 2011). So it looks probable that aspartic acid racemization does not provide grossly inaccurate estimates of old age - why would Narwhals live to be centenarians? Garde et al. (2007) note that Narwhals and Bowheads are both year-round Arctic residents and speculate that their extreme longevity is an adaptation to drastic changes is climate. While an interesting idea, there does not seem to be much data available on cetacean longevity (Table 2 in Garde et al. 2007 has only 12 out of ~80 species) and Narwhals are apparently not far older than other cetaceans (for instance, Orcas apparently live to be 90). It could be possible that further investigation into cetacean longevity will reveal that lifespans of over a hundred years are perfectly normal.

References:

Fontanella, J. E., Fish, F. E., Rybczynski, N., Nweeia, M. T., & Ketten, D. R. (2010). Three-dimensional geometry of the narwhal (Monodon monoceros) flukes in relation to hydrodynamics. Marine Mammal Science 27(4), 889-898. Available.

Garde, E., Heide-Jørgensen, M. P., Hansen, S. H., Nachman, G., and Forchhammer, M. C. (2007). Age-specific growth and remarkable longevity in Narwhals (Monodon monoceros) from West Greenland as estimated by Aspartic Acid Racemization. Journal of Mammalogy 88(1), 49-58. Available.

George, J. C., Follmann, E., Zeh, J., Sousa, M., Tarpley, R., Suydam, R. Horstmann-Dehn, L. (2011). A new way to estimate the age of bowhead whales (Balaena mysticetus) using ovarian corpora counts. Canadian Journal of Zoology 89(9), 840-852. doi: 10.1139/z11-057

George, J. C., and Bocktoce, J. R. (2008). Two historical weapon fragments as an aid to estimating the longevity and movements of bowhead whales. Polar Biology 31(6), 751-754. Available.

George, J. C., Bada, J., Zeh, J., Scott, L., Brown, S. E., O'Hara, T., & Suydam, R. (1999). Age and growth estimates of bowhead whales (Balaena mysticetus) via aspartic acid racemization. Canadian Journal of Zoology 77, 571-578.

A Baby Cadborosaur No More. Part 9: ... and the rest!

Woodley et al. (2011) didn't just concern itself with poachers, pipefish, and 'Cadborosaurs'; everything vaguely similar to the Hagelund specimen in the region was considered. Just in case.

Aulorhynchus flavidus from Flickr user jmandecki.

Tube-snouts (Aulorhynchus flavidus) are pipefish-like relatives of sticklebacks (Gasterosteiformes) which fit the Hagelund specimen's proportions, head shape, and coloration. The dorsal, anal, and pelvic fins are small and transparent and thus possible to overlook. The forked caudal fin could be confused for overlapping fins if folded. Lateral scutes are present, albeit not extensive (illustrated here); it could be possible for the scutes and spines before the dorsal fin to suggest more extensive armor to an eyewitness.

Tube-snouts appear to swim primarily with their pectoral fins while keeping their bodies stiff (similar to poachers, sans ground effect), which makes sustained undulatory locomotion seem improbable. The largest known specimen was 18.8 cm in total length (Bayer 1980), which is less than half of the Hagelund specimen's reported length and hugely problematic for Tube-snouts as candidates.

From Wikipedia Commons.

The Green Sturgeon (Acipenser medirostris) reaches sizes far beyond 40 cm. The extensive bony scutes, barbels (= "whiskers"), and elongated body are interesting similarities with the Hagelund specimen. The major problem is that the dorsal, anal, and pelvic fins are prominent and don't seem capable of folding, unlike the other, more derived candidates. Plus, you'd think a sturgeon would be recognizable... but you never know.

From Wikipedia Commons.

Cutlassfishes (Trichiuridae) are interesting candidates as they are unambiguously eel-like, capable of anguilliform locomotion, have vestigial or outright absent pelvic fins, and (unlikely quite a few of the candidates) have teeth.

The Pacific Black Scabbardfish (Aphanopus arigato) and Pacific Scabbardfish (Lepidopus fitchi) both exceed 40 cm and have strongly forked caudal fins; neither fits the coloration, however. No cutlassfishes have scales, let alone plate-like ones, which can be viewed as a critical problem.

bc-spot-prawns-alive from Flickr user Island Vittles.

Staude and Lambert suggested that the Hagelund specimen may be a decapod in an editorial responding to LeBlond and Bousfield's description of 'Cadborosaurus' in Amphipacifica... an amphipod publication. In order for this identification to work, the "whiskers" would be head appendages (antennae, mandibles, maxillae), the "head" would be the carapace, the "fuzz" would be thoracic and abdominal appendages (maxillipeds, pereiopods, pleopods), the "plate-like scales" would be segments, and the tail appendages would be uropods. This is certainly thought-provoking, but it would require Hagelund to somehow fail to distinguish a vertebrate from an arthropod. There also aren't any obvious candidates, with the largest (Pandalus platyceros - pictured above) being around half the size of the Hagelund specimen with a radically different coloration and proportions.

From Wikipedia Commons.

The Hagelund specimen is surprisingly similar to pinnipeds, as it is the only group to possess a similar appendage arrangement (in phocids, at least), have true whiskers and fur, and be unambiguously coded as having a "seal-like face". Various pinnipeds also demonstrate long heads, slender bodies, and sorta similar coloration. Describing a pinniped as "eel-like" and "undulatory" is problematic, and the lack of plate-like scales and much larger size (even when born) are critical flaws. If the Hagelund specimen were to be taken literally and assumed to be a cryptid, a pinniped would be the most likely identification (far more so than 'Cadborosaurus'); of course, a misinterpreted known fish would be far more likely.


References:

Bayer, R. D. (1980). Size and Age of the Tube-snout (Aulorhynchus flavidus) in the Yaquina Estuary, Oregon. Northwest Science 54(4), 306-310. Available.

Hagelund, W. A. (1987). Whalers No More. Vancouver: Harbour Publishing.

LeBlond, P. H. & Bousfield, E. L. (1995). Cadborosaurus, Survivor from the Deep. Victoria, British Columbia: Horsdal & Schubart.

Woodley, M. A., Naish, D. & McCormick, C. A. (2011). A Baby Sea-Serpent No More: Reinterpreting Hagelund's Juvenile "Cadborosaur" Report. Journal of Scientific Exploration 25(3), 495-512.


Previous entries:

A Baby Cadborosaur No More. Part 1: Introduction

A Baby Cadborosaur No More. Part 2a: Hagelund's Account

A Baby Cadborosaur No More. Part 2b: Hagelund's Account - annotated

A Baby Cadborosaur No More. Part 3: Dealing With Traits

A Baby Cadborosaur No More. Part 4: What is 'Cadborosaurus'?
A Baby Cadborosaur No More. Part 5: Hagelund's Specimen And The Cadborosaurus
A Baby Cadborosaur No More. Part 6a: Cold Water on the 'Reptilian Hypothesis'
A Baby Cadborosaur No More. Part 6b: Reptilian Reproduction
A Baby Cadborosaur No More. Part 7: Poachers
A Baby Cadborosaur No More. Part 8a: Pipefish in a Bucket
A Baby Cadborosaur No More. Part 8b: The Bay Pipefish

Tet Zoo Coverage: 
A baby sea-serpent no more: reinterpreting Hagelund’s juvenile Cadborosaurus

Picture of the Indiscriminate Interval #000004b - Megalocnus rodens

The unusual skull from the last article does not belong to some huge rodent, glyptodont, diprotodontid, or Thylacoleo - it is from the extinct Cuban sloth Megalocnus rodens. This particular specimen was part of a panoply of sloths at the American Museum of Natural History:

Megalocnus is in the foreground, with Megalonyx facing towards it, Scelidotherium facing away, and Lestodon rearing up in the background. 

Megalocnus is probably a member of the clade Megalonychidae, which can be distinguished (in part) by canine- or incisor-like first upper and lower teeth (Gaudin 2004). It may come as a surprise that megalonychids are still with us, as Choloepus (Two-Toed Sloths) are living representatives, and grouped closely (albeit not strongly) with Megalocnus and other Antillean sloths in at least one phylogeny (Gaudin 2004). Yes, this means that Two- and Three-Toed Sloths are distant relatives, with the former being far more closely related to large-bodied 'ground sloths'. I'd recommend this article from the old Tet Zoo for a sloth primer - they're far more diverse and interesting than they're often given credit for, although I suppose that's true of just about any group.

Note the radically different skull of Scelidotherium - it is a mylodontid unlike the other two megalonychids. 'Ground Sloths' are far from a homogeneous group. 

The most striking aspect of Megalocnus rodens is the vaguely rodent-like skull, and it was in fact initially described as a giant rodent from an incomplete mandible (de Paula Couto 1967). While the chisel-like first teeth look particularly rodent-y, the overall dentition is similar to Megalonyx (de Paula Couto 1967). Compared with the other sloths on display, M. rodens displays an elongated neck, heavy body, short tail, and plantigrade hands and feet (de Paula Couto 1967). M. rodens may have been the second-smallest 'ground sloth' on display at the AMNH (Hapalops is slightly out of view), however it was still a large animal which may have weighed about 150 kg (330 lbs) in life (van der Geer et al. 2010). Not bad for a terrestrial Cuban mammal


Megalocnus rodens is most notable for when it went extinct - the latest fossil dates from 4200 years before present (MacPhee et al. 2007). These sloths were still trundling about when the Great Pyramid of Giza was hundreds of years old. All mainland sloths, except of course Bradypus and Choloepus, were extinct by about 10,000 years ago; in contrast, the Antilles had 13 species of sloths in the late Quaternary (Steadman et al. 2005). Most remarkable of all, M. rodens appears to have co-existed with humans on Cuba for over a millennium (MacPhee et al. 2007). There does not appear to be any clear evidence for how the sloths went extinct, although a 'long-fuse' model of human predation would appear to be the most likely. If only they held on for a few more millennia.


References:

Gaudin, T. J. (2004). Phylogenetic relationships among sloths (Mammalia, Xenarthra, Tardigrada): the craniodental evidence. Zoological Journal of the Linnean Society 140, 255–305. Available.

van der Geer, A., Lyras, G., de Vos, J., and Dermitzakis, M. (2010). Evolution of Island Mammals: Adaptation and Extinction of Placental Mammals on Islands. John Wiley and Sons. Partially Available.

MacPhee, R. D. E., Iturralde-Vinent, M. A., and Vazquez, O. J. (2007). Prehistoric Sloth Extinctions in Cuba: Implications of a New “Last” Appearance Date. Caribbean Journal of Science 43(1), 94-98. Available.

de Paula Couto, C. (1967). Pleistocene edentates of the West Indies. American Museum Novitates 2304: 1–55.

Steadman, D. W., Martin, P. S., MacPhee, R. D. E., Jull, A. J. T., McDonald, H. G., Woods, C. A., Iturralde-Vinent, M., and Hodgins, G. W. L. (2005). Asynchronous extinction of late Quaternary sloths on continents and islands. PNAS 102(33), 11763-11768. Available.

Picture of the Indiscriminate Interval #000004a - Not A Rodent

I'll try something new here - can anyone out there identify this skull? As the title hints, this is not a rodent...

Dorudon Was Not A Monster

The external shape of cetaceans is very much defined by blubber and other soft tissues†. In a previous article, I argued that if a cetacean were to be naïvely reconstructed by what the skeleton (or rotten carcass) 'suggests', it could end up looking more like a reptilian horror than, say, a fat, charismatic monodontid we all know and love. It's below the monstrous footnote.

† But don't just take my word for it - the Woods Hole Oceanographic Institution has excellent CT scans showing the interplay between skeleton and external shape. Aside from the caudal peduncle and (occasionally) the tip of the snout, toothed whales are cocooned in blubber. The heads of the False Killer Whale and Narwhal provide sufficiently extreme examples. Contrarily, the Minke Whale has a skull which roughly correlates with the external shape... in a dorsal view; shrink-wrapping the skull at a different angle shows that soft tissue still plays a considerable role in determining overall shape. Dorudon probably looked a great deal more like toothed than baleen whales, however more basal 'baleen' whales (stem-Mysticeti) lacking the hyper-derived skull are potentially very informative. Thanks to Markus Bühler for the link.

This intentionally incompetent Beluga bears an unexpected similarity to some reconstructions of Dorudon... notwithstanding the blowhole and fur, of course. This is partially due to the offending illustrations depicting Dorudon atrox with almost no blubber, which makes as much sense as reconstructing a fossil bird without feathers. The other factor is that skeletally, Dorudon is broadly similar to modern toothed whales, despite being basal to the toothed/baleen whale split:

Delphinapterus leucas skeleton from Wikipedia Commons.

Dorudon atrox2, taken and modified from Wikipedia Commons. Note that the arm is held at an angle and was not, in fact, really really short.

White-sided dolphin, taken and modified from Wikipedia Commons.

Above Dorudon is a Beluga, which is similar in size and also has non-fused neck vertebrae (Uhen 2004). What I find particularly striking is the similar depth of the ribcages and the comparatively short spinous processes of Dorudon. Beaked whales also have non-fused neck vertebrae and Ziphius in particular has been compared in size to Dorudon (Uhen 2004) - judging by this photo of Ziphius, the species also has a deep ribcage and relatively enormous spinous processes†. Below Dorudon is a Lagenorhynchus dolphin (either L. acutus or L. obliquidens) which has numerous highly derived characteristics (Buchholtz and Schur 2004), and thus makes for strong contrast. The ribcage seems relatively streamlined and shallower and the spinous processes of the vertebrae are extremely developed. There's still a broad similarity between Dorudon and that highly derived taxon, which makes portrayals of Dorudon as some anguilliform quasi-reptilian horror appear increasingly bizarre.

† Aside from which, the lumbar/anterior caudal region gives off a strong Basilosaurus vibe due to the elongated vertebral bodies and lack of interlocking processes. Hmm.


So why have I been talking so much about Dorudon atrox as opposed to D. serratus, Chrysocetus, Ancalecetus, or some other 'dorudontine'? Dorudon atrox is the best-known 'archaeocete', and at present "[r]elationships among the Dorudontinae are not well-defined, either by morphology or stratigraphy... [i]n addition, the relationships among the Dorudontinae cannot be determined until the taxa within the Dorudontinae are clearly delimited" (Uhen 2004). Additionally, it's become apparent that I've been citing Uhen (2004) quite a bit so far, and that source just so happens to be a massive, book-length treatise on D. atrox which is freely available. The publication is outstanding... aside from the frontispiece, which was credited as being made in cooperation with the author, but seems to contradict several points made within the publication and looks more like a zombie than a fairly close relative of extant cetaceans.

I think I can do Dorudon a bit more justice... next post.

Well, I've actually already done it for the banner - but the explanation will be in the following post! Which won't be in a month, I swear.

References:

Buchholtz, E. A., and Schur, S. A. (2004). Vertebral osteology in Delphinidae (Cetacea). Zoological Journal of the Linnean Society 140, 383–401. Available.

Uhen, M. D. (2004). Form, Function, and Anatomy of Dorudon atrox (Mammalia, Cetacea): An Archaeocete from the Middle to Late Eocene of Egypt. University of Michigan Papers on Paleontology 34, 1-222. Available.

Of the Monstrous Pictures of Whales

"But it may be fancied, that from the naked skeleton of the stranded whale, accurate hints may be derived touching his true form. Not at all. For it is one of the more curious things about this Leviathan, that his skeleton gives very little idea of his general shape"

- Herman Melville. Moby-Dick; or, The Whale. Chapter 55.

Suspiciously similar to a photo taken by Markus Bühler.

What would be made of cetaceans if they were known only from fossil bones? The reconstruction above shows how a mildly unusual Sperm Whale (Physeter macrocephalus) may appear in this hypothetical alternate reality. The unfortunate cetacean is subjected to almost unadulterated 'shrink-wrapping', with the exception of the 'forehead' region. This area of the skull has a strongly concave surface which would look highly implausible on an aquatic creature. What the angle of the reconstruction fails to show is that the concavity is part of a basin-like depression which covers most of the Sperm Whale's cranium; coupled with crests for the attachment of the maxillonasalis muscle, it should be clear that vast amounts of soft tissue were present. The soft tissue is so considerable in mass that Clarke (1978) referred to the head of a Sperm Whale as "largely snout and the crest of the skull necessary to support it". 

A huge nose can be inferred from a Sperm Whale skeleton, yet Melville's assertion is still likely correct. A sloping, prow-like snout would probably be viewed as most likely due to the shape of the skull and hydrodynamic concerns. It seems unlikely, if not impossible, for internal structures such as the spermaceti organ, junk, museau de singe, and distal sac to be inferred; the first two have a major influence on external appearance, as demonstrated by Carrier et al. (2002). Who knows what functional morphology would be hypothesized without knowledge of the complex inner anatomy of the snout, but with knowledge of the strong asymmetry, lack of functional teeth, and a big lump of tissue that must be doing something other than fill out a basin-shaped skull. 

Thanks to cryptozoology, hypothetical alternate realities are not needed for cetacean remains to be grossly misinterpreted. I really couldn't ask for a better springboard for showing off the ludicrous contrast between the skeleton and life appearance in cetaceans.

Above is an extremely literal reconstruction of the 'hairy' Russian 'plesiosaur' carcass. The position of the nostrils is unambiguously cetaceous, but surely the head is too crocodilian and the body too serpentine for this to be a known species? Nah, the skeletal morphology is unambiguously identical to that of a Beluga whale (Delphinapterus leucas). Who knew that beneath all that blubber and muscle, Belugas were reptilian monsters?

Delphinapterus leucas skeleton from Wikipedia Commons.

Beluga, from Flickr user Travis S.

What I find particularly striking is how much of this cetacean's mass lies outside of the ribcage, and that the ribcage appears to have very little 'influence' on the overall shape of the animal.

Delphinapterus leucas head 3 - taken and modified from Wikipedia Commons.

It seems that a few suggestions of the underlying skull can be seen on the live Beluga's head, but it still seems amazing that the two have anything to do with one another.

---

In 1996, a 'dragon' skeleton was pulled out of the ocean in Langkawi, Malaysia. The only available photo is unfortunately tiny, but the shape of the skull as well as the shape and number of the teeth make an Orca (Orcinus orca) identity probable. That, and it was identified as such.

Based on this.

The situation is essentially the same as that of the Beluga, but with a scarier and vaguely crocodilian head. I think that this shows that, underneath that adorable layer of blubber and high-contrast markings, Orcas are capable of serious macropredation.

---

The Ataka carcass - Worst 'Mystery' Ever.

Something like 6-7 years back in Rhode Island, a local news station ran a brief blurb on a carcass similar in condition to the Ataka specimen being unceremoniously disposed of. It was identified as a Humpback Whale (Megaptera novaeangliae) and nobody appeared to have given it a second thought. The Ataka carcass itself is similarly a complete non-mystery - it was unambiguously identified as a Bryde's Whale shortly after washing up. Even Heuvelmans' great tome, In the Wake of the Sea-Serpents, summarily lists it as such. It is then utterly baffling that some cryptozoology sites insist that this is still a valid mystery. Apparently, some people sincerely believe that this is roaming the oceans:

A thin membrane was added between the tusks so it would have some semblance of functional morphology. Baleen whales probably have the most 'alien' looking mammalian skulls around, so it is quite difficult imagining what a blind reconstruction would look like. I'll admit I just wanted to draw something which looked like a bird skull with pincers coming out of it.

This article is a runaway introduction to a somewhat more rigorous topic - giving extinct whales proper amounts of soft tissue. Yes, shrink-wrapped cetacean reconstructions have been done in all sincerity despite, as this post hopefully demonstrated, that making no sense whatsoever.

References:

Carrier, D. R., Deban, S. M., and Otterstrom, J. (2002). The face that sank the Essex: potential function of the spermaceti organ in aggression. The Journal of Experimental Biology 205, 1755-1763. Available.

Clarke, M. R. (1978). Structure and Proportions of the Spermaceti Organ in the Sperm Whale. Journal of the Marine Biological Association of the United Kingdom 58, 1-17. Available.

Book Review: True Giants

All these books just sitting there, un-reviewed...

I was thrilled to learn that Mark A. Hall and Loren Coleman wrote a new book on True Giants. My copy of Mark A. Hall's self-published The Yeti, Bigfoot & True Giants (1997) was read and re-read to the point of near-disintegration, so I'm anxious to both have a more structurally sound tome on 'True Giants' and to see how the hypothesis has evolved. The concept of 'True Giants' goes Beyond The Impossible, postulating that there's a primate bigger than Bigfoot present on multiple continents, whose interactions with humans in the past caused the ubiquitous legends of giants, including those of the anthropophagus variety. The concept of a giant hairy entity following, competing with, and even culturally mimicking Homo sapiens is fascinating - and scary, I've had at least one nightmare about it - and probably a potential goldmine for speculative fiction. However, I am not convinced that 'True Giants' are a valid category of cryptid with the evidence presented.

Major Issues:

Folklore and Cryptozoology

Mezzotint etching of The Giant/The Colossus, by Goya (?).  From Wikipedia Commons.

The pursuit of locally known but officially undescribed species resulted in some of van Roosmalen's amazing discoveries, so I'd say the 'ethnoknown' aspect of folklore is very promising for (crypto)zoology.True Giants includes legends, fables, and traditions such as Grendel, the toll-demanding giant which gave Antwerp its name, and the anthropophagus Ai Kanaka from Hawai'i which I have no more reason to believe than Kings in Mountains, El Dorado, or the Flying Dutchman. Unless the folklore in question is recent (preferably within the lifespan of an eyewitness) and shows an in-depth and realistic understanding of a cryptid, I don't think it should be treated as anything more than a curiosity. As for why giants are ubiquitous in human culture, they can have symbolic purposes (the above etching possibly comments on the Peninsular War), heroic figures can become inflated in size* (Tolkien was probably aware of this trope when he made Elendil nearly 8 feet tall), A Book of Giants suggests they are often used in fables regarding wits over brawn, and of course I suspect there's a universal fascination with things that are big, powerful, and anthropomorphic.

* Went by the name of Homer. Seven feet tall he was, with arms like tree trunks. His eyes were like steel, cold, hard. Had a shock of hair, red like the fires of Hell.

Thorkild hos Udgaardsloke by Louis Moe. From Wikipedia Commons.

For the most part, True Giants treats folklore extremely literally. The foolishness of giants in fables is taken to indicate that 'True Giants' were stupider in the past and only recently learned to avoid humans. The ubiquity of legendary giants caused the authors to propose the presence of 'True Giants' on every permanently inhabited continent, as well as island groups such as Hawai'i and the Solomon Islands. 'True Giants', despite their alleged stupidity, are also postulated to have been capable of rafting (as implied by their presence on the aforementioned islands), speaking human languages as well as their own, herding animals, and the use of advanced technology such as smithing, thanks to legends. To me, this just screams that legendary 'True Giants' are Homo sapiens inflated in scale due to storytelling.

Legendary 'True Giants' up to 20 feet (~ 6) tall are taken literally, although one Chinese tale of a 50 foot (15.25 m) giant is conceded to be a probable exaggeration (thankfully). Many folk tales are full of bizarre traits such as "double eyebrow", "bludging red eyeballs", "eyes as big as saucers"*, "[head] drawn in somewhat like a terrapin", "only one leg or eye", backwards feet, and so forth which are not commented on. One legendary giant wearing a "little hat" is interpreted to have been a reference to a sagittal crest, despite giants wearing clothes (even belts) in other tales. It just seems really strange to me that the authors would cherry-pick some very strange straits, and ignore or explain away others.

* Probably physically impossible for a terrestrial creature.

Overall, True Giants has far too much emphasis on legends. I think folk-giants can be very interesting, so long as they are not taken to indicate flesh-and-blood creatures and analyzed in Folkloristics rather than cryptozoology.

Estimating Giants

Consider Leonid Stadnyk, who claims to be 2.54 m (8' 4") tall - and was once given the title of the world's tallest living man by Guinness - yet appears to be of surprisingly modest height* when a person verified to be that size is shown standing next to an already tall person. The point is - Stadnyk almost got away with considerably exaggerating his height despite being photographed extensively, which suggests to me that the average person is terrible at estimating heights a few standard deviations outside of the norm. This creates huge problems for the concept of 'True Giants' which, aside from their alleged unusual foot morphology, are distinguished from other cryptid hominids by being at least 10 feet (~ 3 m) tall. Am I to seriously believe that a 9 foot 'Neo-Giant' and 12 foot 'True Giant' can be readily distinguished by a height estimated by eyewitnesses who got a cursory glance and (usually) no frame of reference? I only managed to find 2 references to feet with four toes being connected with a height - one 22 inch foot supposedly belonged to an 8 foot creature and a 20 inch foot was supposedly from a 12 foot creature. Assuming the tracks and sightings have any basis in reality, it would suggest that eyewitnesses are capable of grossly inaccurate estimates.

* The man he is standing next to is former Ukrainian president Viktor Yushchenko, who is about the same height as George W. Bush, and thus probably around 6' or 1.83 m.

Taking measurements from cryptid sightings literally is a potential minefield. I see no reason to classify a creature as a 'True Giant' based on alleged height alone, which means most of the observations have no business being classified so specifically. Oh yeah, and there's also the problem of an undiscovered species attaining a height of 20 feet (6.1 m) - which is of course taller than the record giraffe.

Four-Toed Tracks

I was hoping this was a reference to True Giants in mainstream TV-land. Alas, it's yet another inexplicable and ultimately unimportant mystery.

By far the most interesting evidence presented for 'True Giants' are tracks with only 4 visible toes. I counted 14 reported cases in True Giants, with most being reported from western North America (Washington, Oregon, Idaho, British Columbia, Alberta, Manitoba), but also eastern North America (Pennsylvania, Mississippi), Central Asia (Tajikistan), and Southeast Asia (Indonesia, Malaysia). They range in length from 14 to 31 inches (n = 14, median = 20", mode = 20", average = 21", stdev = 5") and in width from 6 to 17 inches (n = 8, median = 9", mode = 6", average = 10", stdev = 4"). Unfortunately, only 3 of the tracks have been depicted (2 of which are in Mark A. Hall's prior book): the 30" x 13" track from Johor has very round toes in a slightly sloping line and tapers into a pronounced heel; the 19.25" long Tajikistan track seems to have  a more rounded heel and pronounced sloping toe-line; the 15" x 6" Mississippi track seems to have a very strait toe-line and round heel (as well as a possible projection from the side, where an opposing ape-like hallux could be). As for how the length and width compare, it isn't a particularly great trend.

I would have preferred it if the authors documented all of the known 4-toed tracks. Are there casts? Is there similar overall morphology? If there evidence of dermal ridges or differing depths within the track which would be difficult to fake? The tracks are potentially very interesting, but ultimately left very mysterious by the book.

It's noteworthy that 10 other footprints were mentioned where the number of toes is not mentioned; these appear to have been connected to 'True Giants' due to their size and location - even though you'd think 4 toes would be one of the first things mentioned. One report from Ballachulish, Scotland specifically mentions toes, but not the number. I found two instances where legends stated that the toes of the giants were "normal" and none mentioned an odd number, demonstrating the tenuous connection between legendary giants and 'True Giants'.

Gigantopithecus

Gigantopithecus blacki mandible, from Wikipedia Commons.

The book suggests that True Giants are surviving Gigantopithecus, although offer contradicting opinions on how closely related they are to humans. Compare the contents of page 8:

[T]he fossils that have been found for this particular giant primate have been attributed not to a giant man but, erroneously, to a giant ape. There is no basis in the fossils themselves to support this determination. Rather, it has been merely a popular prejudice among the fossil specialists to make this categorization.

With those of page 101:

Gigantopithecus is a distant relative to humans in the scheme of primate evolution. Nevertheless, True Giants appear to have discovered and learned the characteristics familiar to other successful primates known as hominids. This convergence accounts for these apemen being seen by so many cultures around the world as "Big Men."

The authors appear to be under the impression that Gigantopithecus was preferred over Gigantanthropus since it is now universally viewed as an ape. Even if a taxa is re-interpreted phylogenetically the name stays the same - consider Basilosaurus. Junior synonyms cannot be re-used, so even if a giant man-like ape is discovered (that isn't Gigantopithecus) it can't be called Gigantanthropus - consider Livyatan melvillei and the pre-occupation of Leviathan.

I have never seen Gigantopithecus classified as anything other than a relative of orangutans in recent years, see Harrison (2010) for a recent phylogenetic tree of apes.





Big Bones

'True Giant' bones have a suspicious tendency to crumble away into nothingness, and those that found their way to scientists 'mysteriously' shrink to normal human proportions - see NABR #11 (page 5) for an article on how the decaying tendons and cartilage of normal skeletons made them appear 8 or 9 feet tall, and NABR # 13 (page 3) on how normal human femurs and mandibles have been confused for those of giants, not to mention when bones from large mammals (like mammoths) are confused for those of a human. Therefore, there is absolutely no reason to trust reports of 'giant' bones.

Minor Issues:

Denisovans

To segue into 'True Giants', the introduction (pg. 5-6) brings up a mysterious clade of humans distinct from Homo sapiens and H. neanderthalensis yet sharing genes with both, and suggests they are linked to cryptid Siberian wild-people much in the manner that H. floresiensis is 'linked' to the legendary Ebu Gogo. I feel obliged to comment that the 'hobbit'/Ebu Gogo connection could be a coincidence (legendary 'little people' are found far outside Flores), and connecting a clade described only from molecular data with cryptids known from anecdotally-reported morphology is very premature. In the mad mad mad world* of human origins, it's hard to predict what picture will emerge for the Denisovans (or what else will emerge...), so in the meantime, check out John Hawks Weblog for the story so far.

* The closer to Homo sapiens phylogenetically, the crazier things get.



Dryopithecus

The authors refer to Dryopithecus as a relative of Gigantopithecus - which is technically true of course - but there is some controversy as to where Dryopithecus places phylogenetically, and it could be a stem hominid (outside the African ape + orangutan clade) (Harrison 2010). True Giants claims that Dryopithecus is behind 'Yeti' sightings, yet Dryopithecus is exclusively European (Begun 2005). Since it would have made a lot more sense just to say Sivapithecus instead of Dryopithecus, I suspect True Giants was relying on older literature that combined them into a polyphyletic Dryopithecus (see Begun 2005 for a review). I'd recommend Grehan and Schwartz (2009) as a review on fossil apes... if you overlook the proposed phylogeny.



Shrink-wrapped skull

True Giants claims that a skull-mask from the Mongolian plateau represents a 'True Giant' head. They claim that it has an overall oval-shape, deep-set eyes, and "a peak that is an indicator of the large muscles necessary to operate the massive jaw of this ape-man" (which they connect to the "little hat" giants of Alaska). Note that the skull doesn't have a sagittal crest (which provides an attachment point for jaw muscles), it has a rounded top. How one determines that a representation of a skull has "deep-set" eyes is beyond me, and the interpretation of traits (seen a few times in 'True Giants') comes across as rather forced. A shrink-wrap reconstruction of the skull-mask serves as a logo of sorts for the start of each chapter.



Huh?

I have no idea what this paragraph is about (page 99):

The mean height of True Giants is likely to be in the range of 12-14 feet. This was determined by Lambert Adolphe Jacques Quetelet (1796-1874). This Belgian statistician and astronomer made his judgement based upon the proposed existence of a 20-foot giant [1].

The reference links to Firestone's The Coasts of Illusions. How could this average be determined from one (proposed!) skeleton? Why is this more reputable than averaging the sightings listed?

Such a statement seems especially designed to bait me into going through the book again and documenting all the described heights. So I did. For sightings with given heights (n = 19), the range was from 8-18 feet with a median and mode of 12 feet, and an average of 11.96 feet (stdev = 2.64 feet). When only sightings with toes are considered, the 'n' plummets to 2 - one of an 8 foot creature and one of a 12 foot creature (with the former having larger feet...). For what I consider 'legends' (n = 14), the range was from 9-50 feet with a median of 19 feet, mode of 20 feet, and an average of 20.23 feet (stdev = 11.16 feet). No 'legend' mentioned four toes.



Honeycombed Bones

From Wikipedia Commons.

The authors suggest that since humans can't grow over 9 feet tall, 'True Giants' must have a radically different skeletal structure to allow them to accomplish such towering heights. They raise the possibility of bones with a "honeycomb structure" which could be used to reduce mass, as well as account for why there are so few remains. I'm not sure what is meant by "honeycomb". Cancellous bone is weak, so increased extents of it would make for a rickety giant. Pneumaticity (i.e. the presence of air) is a way of reducing weight and retaining strength which is found in across tetrapods - notably the hyoid of howler monkeys (Alouatta) (Wedel 2005); however, only pterosaurs, theropods (including birds), and sauropods have pneumaticity beyond the cranium (Wedel 2006). I'm going to say that 'True Giants' having a skeletal structure (and presumably respiratory system) convergent upon archosaurs is really, really improbable.

Executive Summary:

While a tantalizing concept, there's no evidence to support 'True Giants' as a valid cryptid. Folklore could have made for a few interesting footnotes or background to some sightings, but it was given far too much emphasis and taken too literally. Most encounters appear to have been classified as 'True Giants' based on the size reported by eyewitnesses; it is extremely unlikely an eyewitness can accurately gauge how tall a cryptid far beyond normal human size is - and since when does another proposed cryptid ('Neo-Giants') have a known size limit? The large four-toed tracks are by far the most interesting part of True Giants, but remain cryptic even in this hyper-specific volume. Future volumes desperately need to document the footprints to the greatest extent possible - preferably gathering casts and analyzing the possibility it came from a living creature. I should add that I would bet against the possibility of 'True Giants', 'Bigfoot', et al. existing, but that doesn't mean I think they deserve to be ignored, and I'd be willing to change my mind if sufficient evidence turns up.



True Giants: Is Gigantopithecus Still Alive? is available at Amazon, Barnes & Noble, and Books-A-Million. I'm mentioned on page 157 (in a discussion on Meganthropus) and Markus Bühler is on page 71 (he took a photograph of an unusual orangutan-like sculpture).



References:

Begun, D. R. (2005). Sivapithecus is east and Dryopithecus is west, and never the twain shall meet. Anthropological Science 113 (1), 53-64. Available.

Grehan, J. R., and Schwartz, J. H. (2009). Evolution of the second orangutan: phylogeny and biogeography of hominid origins. Journal of Biogeography 36 (10), 1823-1844. DOI: 10.1111/j.1365-2699.2009.02141.x. Available

Harrison, T. (2010). Apes among the Tangled Branches of Human Origins. Science 327 (5965). DOI: 10.1126/science.1184703. Available

Wedel, M. J. (2006). Origin of postcranial skeletal pneumaticity in dinosaurs. Integrative Zoology 1(2), 80-85. DOI: 10.1111/j.1749-4877.2006.00019.x. Available

Wedel, M. J. (2005). Postcranial skeletal pneumaticity in sauropods and its implications for mass estimates; pp. 201-228 in Wilson, J.A., and Curry-Rogers, K. (eds.), The Sauropods: Evolution and Paleobiology. Berkley: University of California Press. Available.