The Cephalocarids

Cephalocarids, literally 'head shrimp', are superficially reminiscent of those other oddball arthropods I covered, the remipedes. Both are 'class'-level crustacean clades discovered in the latter half of the 20th Century and assumed to be 'extremely primitive' on the basis of traits such as elongation, undifferentiated trunk appendages, and weak tagmosis (formation of head/thorax/abdomen by fusing 'segments') (Ruppert et al. 2004). Some have pointed out that arthropods should probably be described as 'jointed' rather than 'segmented' (Valentine 2004), suggesting the similarity of these 'primitive' clades to annelids is coincidental. A (Cephalocarida + Remipedia) clade has been recovered on occasion, and recently a molecular phylogenetic analysis proposed the taxa to be called 'Xenocarida', or 'strange shrimp' (Reiger et al. 2010). Before I delve into the hyper-controversial world of (pan)crustacean systematics, more background is needed on the cephalocarids.

Dorsal view of Hutchinsoniella macracantha taken and modified from Sanders (1955). The proportionally large head (17-18% length - excluding caudal spines) provides the 'class' name; it should be noted that copepods have similar, if not more extreme, proportions. The purported common name 'horseshoe shrimp' derives from the head shape, but I'm not enthusiastic about the descriptive value of that name either.

Cephalocarids appear not to exceed 4 mm in length (Ruppert et al. 2004), so it is not particularly surprising that they were overlooked for so long. The first recorded specimen was found in September 1953 in San Francisco Bay, although that species (Lightiella serendipita) was not properly described until Jones (1961). In August 1953 another specimen was found in Long Island Sound, but the actual holotype for Hutchinsoniella macracantha was recovered in July of the next year from the roughly the same locale (Sanders 1955). Confusing! Anyways, Hutchinsoniella specimens from Long Island Sound and Buzzard's Bay were found on muddy bottoms 9-29 m below the surface, although shortly afterwards they were found down to 100 m on a continental slope (Hessler and Sanders 1964). The Lightiella specimens from San Francisco were only found 3 to 5 feet (~0.9 to 1.5 m) below the lowest water level (Hessler and Sanders 1964). The depth record for cephalocarids as a whole is 1550 m, and they have been recorded from sand in addition to mud (Ruppert et al. 2004).

Major cephalocarid discoveries are still being made, and I would certainly look closely at any sand or mud I happen to dredge up. A new species was recently discovered from Japan (Shimomura and Akiyama 2008) and the clade (in the form of a new species) was just described from Europe (Carcupino et al. 2006). Martin et al. (2002) state the presence of cephalocarids anywhere is notable due to their infrequence and considerable interest in their morphology and phylogenetics - so why is that?

Lightiella incisa taken and modified from Martin et al. (2002). The roundish structures are oocytes - all species are hermaphrodites. 

Sanders (1955) noted that cephalocarids share traits with a number of clades such as branchiopods (number of thoracic and abdominal segments), malacostracans (postcephalic appendage morphology), and copepods (large head) - but concluded that they were at least as 'primitive' as branchiopods and probably related to the 'ancestral stock' that gave rise to those clades. Cephalocarids were assumed to be eyeless, but Burnett (1981) recorded the degenerated compound structures in H. macracantha - and used that as further evidence that cephalocarids were almost unchanged from a 'Paleozoic urcrustaceanlike organism'. I'm not particularly impressed with that line of reasoning. Read et al. (1994) found that cephalocarid muscle overall resembles that of other crustaceans, but (along with ostracods) lacks myofibrils in a condition similar to onychophorans, and was assumed to represent a 'primitive' rather than simplified condition. Considering the incredibly small size of cephalocarids (most appear to be between 2-3 mm) the possibility of simplification cannot be casually tossed aside. Elofsson and Hessler (1990) examined the central nervous system of H. macracantha and were surprised to find it highly developed (albeit missing some structures - like eyes, for the most part) and thought that since it didn't conform with the 'overall primitiveness' of the animal, it must have evolved separately from that of other crustaceans! L. incisa appears to prefer oxygen-rich microzones (Martin et al. 2002) - which would seem appropriate for animals with a complex nervous system. It seems that a lot of these systematic inferences were made with the 'primitiveness' of cephalocarids in mind and fitting the evidence into that preconception - so what happens when phylogeny is examined using modern methods?

From Reiger et al. (2010). Note the position of Xenocarida - the sister group of insects!

Reiger et al. (2005) used RNA sequences to hypothesize insects were terrestrial (pan)crustaceans and that branchiopods were their sister group, with a cephalocarid + remipede clade as the sister group to (Branchiopoda + Hexapoda). The authors speculated that members of this clade had a proclivity for near shore or marginal marine habitats, but were excluded by other pancrustaceans and forced into their present unusual habitats (hexapods live on land and freshwater, branchiopods generally in freshwater, and remipedes live in anchialine caves) (Reiger et al. 2005). A prior study using different genes also recovered a cephalocarid + remipede clade and interpreted it to be due to long-branch attraction, but Reiger et al. (2005) argue that it could be interpreted literally. While Reiger et al. (2005) argue that cephalocarids are derived, they could not answer whether or not their morphology is actually plesiomorphic - but noted that prior placements based on the 'ur-crustacean' hypothesis were somewhat anachronistic. It should be noted that a phylogeny determined from mitochondrial protein coding genes failed to recover 'Xenocarida', but did create a clade of branchiopods, malacostracans, cephalocarids, and insects (Carapelli et al. 2007).

I think what we should take away from the phylogenetic work is that the cephalocarid-as-ur-crustacean hypothesis is looking rather shaky and an extensive examination of morphology and molecular data is needed to resolve the phylogeny with anything resembling rigorous support. Cephalocarids are not known from the fossil record, so when or if those discoveries are made, hopefully it will clarify if the morphology is plesiomorphic, simplified, or some combination of the two. The potentially phylogenetically significant placement of cephalocarids probably means our knowledge of them will expanding in the near future and they won't always be so enigmatic. I certainly intend to squint at marine mud the next time I happen across it...

References:

Burnett, B. (1981). Compound eyes in the Cephalocarid Crustacean Hutchinsoniella macracantha. Journal of Crustacean Biology 1(1), 11-15.

Carapelli, A., et al. (2007). Phylogenetic analysis of mitochondrial protein coding genes confirms the reciprocal paraphyly of Hexapoda and Crustacea. BMC Evolutionary Biology 7(2). doi:10.1186/1471-2148-7-S2-S8

Carcupino, M., et al. (2006). A new species of the genus Lightiella: the first record of Cephalocarida (Crustacea) in Europe. Zoological Journal of the Linnean Society 148(2), 209-220. doi:10.1111/j.1096-3642.2006.00237.x

Hessler, R. and Sanders, H. (1964). The Discovery of Cephalocarida at a depth of 300 meters. Crustaceana 7(1), 77-78.

Jones, M. (1961). Lightiella serendipita gen. nov., sp. nov., a Cephalocarid from San Francisco Bay, California. Crustaceana 3(1), 31-46

Martin, J. et al. (2002). First record and habitat notes for the genus Lightiella (Crustacea, Cephalocarida, Hutchinsoniellidae) from the British Virgin Islands. Gulf and Caribbean Research 14, 75-79. Available.

Reiger, J. et al. (2010). Arthropod relationships revealed by phylogenomic analysis of nuclear protein-coding sequences. Nature doi:10.1038/nature08742

Reiger, J. et al. (2005). Pancrustacean phylogeny: hexapods are terrestrial crustaceans and maxillopods are not monophyletic. Proceedings of the Royal Society B 272(1561), 395-401. doi: 10.1098/rspb.2004.2917

Ruppert, E., et al. (2004). Invertebrate Zoology: A Functional Evolutionary Approach. Belmont, California: Brooks/Cole - Thomson Learning.

Sanders, H. (1955). The Cephalocarida, a new Subclass of Crustacea from Long Island Sound. Proceedings of the National Academy of Sciences 41(1), 61-66. Available.

Shimomura, M. and Akiyama, T. (2008). Description of a New Species of Cephalocarida, Sandersiella kikuchii, and Redescription of S. acuminata Shiino Based Upon the Type Material. Journal of Crustacean Biology 28(3), 572-579. doi: 10.1651/07-2864R.1

Valentine, J. (2004). On the Origins of Phyla. Chicago, USA: University of Chicago Press.

Marine Cryptid Art

I've covered marine cryptids extensively on this blog, so I figured one more post couldn't possibly make the proverbial grave I'm digging for my credibility any deeper. I think. In recent posts I experimentally subjected a proposed type of 'sea serpent' report to rigorous qualitative and cladistic analysis, and then set out to determine if another proposed 'type' could be classified amongst marine vertebrates, as the authors claimed. I am convinced that most 'sea serpent' reports are too vague to be classified as anything (mundane phenomena or otherwise) and that proposing a classification for a purported animal which bears no strong resemblance to any known clade is a futile effort. This does not mean that future reports should be ignored or that cryptids which bear an obvious resemblance to known clades (e.g. cryptid beaked whales and dolphins) should be discounted - but I seriously question the continued use of 'sea serpent' types unless some very compelling evidence is documented.

I think sea serpent 'types' are a potential goldmine for those interested in speculative biology. A while ago, I made some drawings for a recent and rather obscure sea serpent classification and did my darnedest to come up with a plausible interpretation of the given description. Just how, I ask, is one supposed to depict a near-spherical animal with a carapace, oily hair, and quills? Here's my best effort, circa 2005:

Yeah...

Tim Morris, aka ~Pristichampsus, informed me that he has been utilizing information from this blog to create his own take on the sea serpent 'types'. Tim's style is in strong contrast to whatever I was doing back then, and he has created some seriously top-notch speculative beasts. Here is his 'Type 5 Carapaced' sea serpent in all of its redoubtable glory:

Image ©2010 ~Pristichampsus. Available.

If you look at the comments, note that none other than Nemo Ramjet suggests this cryptid looks like a potential long-lost relative of Thalassocnus. The aquatic nothrothere sloths occurred from the late Miocene to late Pliocene of southern Peru; the early basal species appear to have grazed on seaweed on or near land as evidenced by sand wear on their teeth, while the more derived species lack that wear and had an elongate rostrum, adaptation for strong lips, and appendicular morphology resembling that of pinnipeds (Muizon et al. 2004a, Muizon et al. 2004b, Muizon et al. 2003) Please read the excellent writeup at Catalogue of Organisms for further discussion on morphology and the possibility of anagenesis in that clade. 

With all respect to Mr. Ramjet, I disagree with the assertion that the 'Type 5 Carapaced' marine cryptid represents a highly derived sloth. While some extinct sloths have bony ossicles, they appear restricted to the clade Mylodontidae (Delsuc et al. 2001 citing Carroll 1988); Thalassocnus is in the clade Megatheriidae. No members of Glyptodontidae are known to be semi-aquatic, but their extensive armor could provide a method of accomplishing negative buoyancy comparable to the pachyostosis of manatee bones. 

While I can't find Champagne's original description of  'Type 5', I recall my nemesis the P/A Index playing a hand in its 'classification' - and of course it is worth noting that turtles are prone to growing hair-like epiphytic algae. No quills though.

Moving on...

Champagne's 'Type 8 Digited' marine cryptid is likely based on poorly-reported frogfish, monkfish, or some other anglerfish species, although we can't be certain as he did not specify which reports constituted the 'type'. Here is Tim's take on the beast:

©2010 ~Pristichampsus. Available.

How this creature is supposed to blend in with seaweed I have no idea. Anyways, rather than go with the seemingly obvious identification of an inexplicably aquatic chameleon, I'll spin the special Prehistoric Survivor Paradigm edition wheel of Phylogenetic Roulette (somebody remind me to physically construct this at some point) and land on drepanosaurs. I wrote about this group back in the primordial days of The Lord Geekington, but to avoid further humiliation I will instead link to the Hairy Museum of Natural History article. Note that drepanosaurs are found in lake-bottom sediments and were proposed to be aquatic at some points in their history, but it is now quite clear they are arboreal. I can't help but wonder if the idea of an aquatic chameleon-like animal heavily influenced this 'type', but it went without mention in the description.

I won't go through all the types here, so here's the link to the rest of the illustrations, and the sea-serpent-stravaganza that is the 'Know your Sea Serpents' amalgamation. It reminds me of this famous mural.

When I'm finished constructing my Random Taxa Wheel, I'll have to exploit the movie monster possibilities of these sea serpents... 

References:

Carroll, R. (1988). Vertebrate Paleontology and Evolution. New York: Freeman.

Delsuc, Frederic, et al. (2001). The evolution of armadillos, anteaters and sloths depicted by nuclear and mitochondrial phylogenies: implications for the status of the enigmatic fossil Eurotamandua. Proceedings of the Royal Society B. 268, 1605-1615. Available.

Muizon, C. et al. (2004a). The evolution of feeding adaptations of the aquatic sloth Thalassocnus. Journal of Vertebrate Paleontology 24(2), 398-410. Available.

Muizon, C. et al. (2004b). The youngest species of the aquatic sloth Thalassocnus and a reassessment of the relationships of nothrothere sloths (Mammalia: Xenarthra). Journal of Vertebrate Paleontology 24(2), 387-397. Available.

Muizon, C. et al. (2003). A new early species of the aquatic sloth Thalassocnus (Mammalia: Xenarthra) from the Late Miocene of Peru. Journal of Vertebrate Paleontology 23(4), 886-894. Available.

How Not To Go About Classifying Marine Vertebrates... And Cadborosaurus

Again with the Cladistics!
In a couple prior posts, here and here, I critically examined a well-known cryptozoological categorization and found that one proposed cryptid 'type' cannot be supported from a qualitative or quantitative standpoint. Heuvelmans' system of classification and its progeny appear to use methodology inspired by evolutionary taxonomy, an 'art form' approach which relies on perceived similarities and differences between taxa (Cracraft 2006). As evolutionary taxonomy has been superseded by cladistics in the last few decades, why haven't those interested in cryptozoology attempted a modern-style parsimony analysis of anecdotal information? There is a preconception that cladistics can only be used to determine the relationships of organisms, which was the original intent, but its principles can be applied to any hierarchal (i.e. groupable) data set (Young 1995). Another preconception is that data cannot be gleaned from anecdotal information, but it is possible so long as the conclusions drawn are limited (Paxton 2009). Cladistic analyses create a large number of trees, making it possible to determine bootstrap values, i.e. how often a certain clade is recovered; I suggest clades above 50% (majority) should be viewed as potentially informative and those with values of 95% (= p value of 0.05) and up can be considered data. Of course, even clades recovered in 100% of trees should be qualitatively reviewed in order to determine if the relation is just a quirk of sampling and/or characters used. 

In my Many-Finned analysis, I found the majority of anecdotal reports vague to the point of uselessness, strongly suggesting that any sort of grouping for this 'type'  is a priori and self-deluding. I understand that cryptozoologists would be wary of a method which recovers many reports as 'noise' and cannot be used to obtain 'proof', but cladistics is a potentially useful method to objectively and scientifically approach unusual information. Cladistics is regularly utilized to determine the molecular phylogeny of purported cryptid material (see Crother et al. 2009), and I see no reason not to expand its usage to other information present in cryptozoology - aside from its somewhat time consuming nature.


Caddy of Cascadia
LeBlond and Bousfield are investigators of a marine cryptid from the Pacific Northwest with the unfortunate moniker of "Caddy" or Cadborosaurus. While their work on collecting reports is commendable, as some are quite compelling, their scientific analysis of the purported species has been heavily criticized and controversial to the degree of causing two editors to resign from the amphipod journal (!) in which a species description was published.

For the sake of argument, we are going to have to assume that the authors had good reason for thinking that 'Caddy' displays the traits they listed, and has a strong enough chance of being a valid species that an attempted phylogenetic analysis would not be a waste of time. These are probably unwarranted assumptions and I'll be upfront that my primary reason for writing this post is to establish a cautionary tale for those interested in unusual anecdotes.

The authors used a form of analysis which was previously utilized in a study of amphipod systematics by LeBlond and another author (which I cannot access), and was justified in the context of classifying cryptids because "[t]he data are far too sparse and soft to use the more mathematical techniques of biological classification" (LeBlond and Bousfield 1995). Needless to say, I am highly dubious about the reasoning behind choosing a special method because the data cannot stand up to more conventional analyses! I have not seen any subsequent uses of the 'P/A Index' in peer-reviewed literature, which in itself is probably quite telling about its applicability.

After LeBlond and Bousfield (1995). Click to enlarge

8 Characters for 8 Clades!
The 'P/A Index' uses 8 broad traits to classify 'Cadborosaurus' amongst marine vertebrates and whatever 'Primitive Mammals' are. The incremental index values (bony fish 3+, amphibians 4+, reptiles 5, 8+, mammals 7, 11, 13) are suggestive of the 'Great Chain of Being', a bizarre Western concept which still pervades popular conceptions of evolution. However, a 'Plesiomorphic/Apomorphic Index' is theoretically possible if the characters used are highly unlikely to have evolved multiple times - non-craniate chordates and craniates can be distinguished on the basis of neural crest cells, non-sarcopterygian vertebrates and sacropterygians on the basis of lobe fins - and so forth - which can create a 'chain' of increasingly derived clades. I cannot see how this index method confers any advantages over cladistics. The authors only used one trait which is highly unlikely to have evolved multiple times, placental reproduction, but, as nobody has reported the presence/absence of an afterbirth, its coding is due to an a priori assumption on the part of the authors.

Before I cover the next enormous problem in LeBlond and Bousfield's index, what happens if take the numbers given in the index at face value and put it through PARS? This tests the assumption that the value given in the 'P/A Index' is at all predictive of phylogeny:

Nope.

The next issue is that the authors used enormous clades consisting of thousands of species, with their variance expressed by '+' and '-'. What happens if we assume that each has a value of 1?


Cadborosaurus: 9-10?

Bony Fishes: 3-5
Amphibians: 3-7
Modern Reptiles: 5
Plesiosaurs: 8-11?
Primitive Mammals: 7-8
Pinnipeds, Advanced Mammals: 9-12
Cetacea: 13

Great Chain of Being no longer! I'm highly dubious about a system which gives similar scores for pinnipeds and plesiosaurs and cannot reliably distinguish fish, amphibians and reptiles. So can the P/A index be salvaged, or is it fundamentally flawed?


The Index Recoded
LeBlond and Bousfield had some very odd choices for coding character states, in fact, I would have done over half of them differently! Some of the problems were very troublesome, most notably that the small head/long neck condition was considered plesiomorphic, which is obviously not the case for a group which includes bony fish! Rather than go through all of the problems and offer a possible explanation, I'll define/refine the possible character states.

Total Length: Was 'Body Size'. Animal size should be expressed in terms of mass, but clearly this is not possible as we are dealing with a cryptid. So let's go by orders of magnitude: State 0 = 0 to 1 m, State 1 = 1 to 10 m, State 2 = 10+ m. Note that State 0 is what I consider to be plesiomorphic, as this is the state for Branchiostoma virginiae (a lancelet) one of the invertebrate chordate outgroups I shall be using.

Fineness: Was 'Body Shape'. 'Elongate' body shapes are considered to be over 7 (see this discussion), and I shall use 14 as the cutoff point for what I shall consider 'serpentine'. Both of my outgroups (a lancelet and a hagfish) are elongate, so I shall assume this was the plesiomorphic condition for vertebrates. State 0 = elongate (fineness 7 to 14), State 1 = compact (fineness under 7), State 2 = serpentine (fineness over 14). One potential issue is that animals which have partial serpentine-like morphology can code as elongate, e.g. Elasmosaurus has a fineness ratio of only 10.2.

Neck Length: Was 'Head and Neck'. State 0 = no neck, State 1 = neck present and of similar/lesser length than head. I shall also accept pseudo-necks present in some fishes, which I shall define as portions of the body which are noticeably more slender than the head (e.g. narrowneck eel, sea horse). State 2 = neck far longer in length than head, comparable to swan or plesiosaur. This is a bit more nebulous than I would like, but should serve us well for the taxa considered.

Paired Appendages: Formerly 'Number of Legs'. The name was changed in order to account for the pectoral and pelvic appendages of fishes (which the authors considered legs...). State 0 = appendages absent, State 1 = 1 pair, State 2 = 2 pair. The lack of appendages is a plesiomorphy as evidenced by the lancelet and hagfish. Unlike LeBlond and Bousfield, I still count appendages if they are reduced or have a novel orientation.

Caudal Appendage: Formerly 'Tail Style'. The name was changed in order to account for appendages located near the tail (e.g. hind flippers of pinnipeds) that could look as if they were bilobate. State 0 = vertical caudal appendage, State 1 = no caudal appendage, State 2 = bilobate or bilobate-like caudal appendage.

Thermoregulation: Formerly 'Thermal Physiology'. State 0 = Ectothermic regulation, State 1 = Homeothermy via Rete mirabile, 'Gigantothermy', et cetera. Bradymetabolic animals. State 2 = Endothermy (heat via metabolic rate), Homeothermy (stable internal temperature), Tachymetabolism (high resting metabolism).

Reproduction Location: Not where the sex occurs, but where young are spawned/born. State 0 = Aquatic, State 1 = Terrestrial (as depicted by LeBlond and Bousfield, there's no way 'Caddy' could haul out on land to reproduce).

Reproduction Type: State 0 = Oviparity, State 1 = Viviparity and Ovoviviparity (lumped to eliminate a priori reasoning).


Now with the characters more sensibly defined, we need to abandon the huge clade categorizations and use individual taxa. I'm using 30 taxa which should provide a reasonable sample of the diversity of marine and semi-aquatic vertebrates. I specifically went for large and morphologically unusual species:


Branchiostoma virginiae (Amphioxiformes)


Eptatretus goliath (Myxini)


Huso huso (Acipenseriformes)
Anguilla anguilla (Anguilliformes)
Derichthys serpentinus (Anguilliformes) - been meaning to blog about this one for a while
Poecilia reticulata (Cyprinodontiformes)
Monopterus indicus (Synbranchiformes)
Regalecus glesne (Lampriformes) - I am not certain if they can actually reach 10 meters.
Benthodesmus tenuis (Trichiuridae)
Thunnus thynnus (Scombridae) - yes, it has regional endothermy.

Bufo marinus (Anura)
Andrias davidianus (Caudata)
Amphiuma tridactylum (Caudata)
Chthonerpeton viviparum (Gymnophiona)

Dermochelys coriacea (Chelonia) - an endothermic species which even has mammal-style blubber.
Chitra chitra (Chelonia) - I have no idea how this neck can contract (and it does...)
Varanus komodoensis (Squamata)
Eunectes murinus (Squamata)
Hydrophis spiralis (Squamata)
Crocodylus porosus (Archosauria)
Cygnus olor (Archosauria)
Mauisaurus haasti (Plesiosauria)

Ornithorhynchus anatinus (Monotremata)
Ondatra zibethicus (Rodentia)
Pteronura brasiliensis (Carnivora)
Eumetopias jubatus (Carnivora)
Hydrurga leptonyx (Carnivora)
Phocoena phocoena (Cetacea)
Lissodelphis borealis (Cetacea)
Balaenoptera physalus (Cetacea)

'Caddy' (Unknown)


And their character states:

Click to enlarge

Note that giant salamanders, sturgeons, eels, and eel-like fishes have the same score (4); as do caecilians, oarfish, tuna, and crocodiles (6); softshell turtles and platypi (8); muskrats and anacondas (9); and so forth. It's clear that this index can only be used for the broadest of classifications (fish vs. mammals) and that 'Caddy's' score is essentially meaningless. Of course, there's still one thing I'd like to do:

...and that's why you don't use 8 homoplastic characters to determine the phylogeny of vertebrates!

After subjecting the data to the regular regiment, a phylogenetic tree emerges that is about as traumatizing as watching J. Walter Weatherman getting his arm unexpectedly and repeatedly amputated at several points throughout my childhood. My favorite is the marine toad/guppy clade.


Piecing together dissociated knowledge to open up terrifying vistas of reality

1. As depicted by LeBlond and Bousfield (1995), 'Cadborosaurus willsi' resembles a secondarily aquatic vertebrate - but that's about the limit of what can be said.
1. Their depiction appears to be heavily based on the Naden Harbour carcass.
2. There is a distinct possibility that said carcass is that of a basking shark
1. Has anybody ever commented on how featureless the 'skull' is and all those weird projections coming out of the neck? 
2. LeBlond and Bousfield (1995) classified 'Caddy' amongst the marine vertebrates using 8 characters.
1. It might be possible to get a crude topology of vertebrates using 8 characters (e.g. presence of lobe-fins, amnion, dentary-squamosal jaw joint, avian-style wings, et cetera) which have almost certainly evolved once.
1. None of these traits are observable/inferable from 'Caddy' reports. 
2. Almost all of the traits the authors used have evolved numerous times, dozens for some.
3. The characters they used were vaguely defined.
4. The authors compared 'Caddy' with different vertebrate 'classes'.
1. Those groups are composed of thousands of species.
2. Their character states cannot be accurately represented with a number and a character.
5. LeBlond and Bousfield (1995) had some very questionable coding:
1. According to the P/A Index:
1. All 'Modern Reptiles' are serpentine and have long necks
2. 'Modern Reptiles' and 'Bony fish' are always 'cold blooded'.
3. Plesiosaurs occasionally have less than 4 limbs and horizontal tail flukes.
4. Pinnipeds have a single pair of limbs and sometimes more
5. Cetaceans, 'Modern Reptiles', and Amphibians have the same number of limbs.
6. Et cetera.
3. LeBlond and Bousfield (1995) count up the number of apomorphic characters as if that means something.
4. 'Cadborosaurus' placed ambiguously (9?)
1. "Overall, Caddy ranks most closely with marine saurischian [sic] (plesiosaurs) or thalattosuchian (marine crocodilians) reptiles and marine mammals, which is perhaps not too surprising. To be more definite, one has to weigh the relative importance of the various characteristics." (LeBlond and Bousfield 1995, p.82).
1. Saurischia = Theropoda (including Aves) + Sauropoda
2. Read: The traits that give the desired identification will be weighted.
2. The authors make the following arguments for why 'Caddy' is a reptile:
1. Reported hair may be "something else" 
1. [Pseudo-hair? What about reported whiskers?]
2. While "no living reptiles are capable of bending their spines in the vertical plane" - marine crocodiles had whale-like vertebrae and were capable of vertical flexure
1. [Assuming the latter point is even true, the authors do not understand the difference between vertical flexure and vertical undulation. Not even all mammals locomote with vertical undulation.]
3. Slenderness and implied considerable surface area in cold waters implies that 'Caddy' is 'poikilothermic'.
1. [Yet they claim it is an extremely fast swimmer and can fold itself into a compact form comparable with tunas and orcas!]
4. Reported precocial young were very small in comparison with adults like reptiles.
1. [Extremely wrong. This shall be answered elsewhere.]
5. On the plus side, the authors don't there there is enough evidence for multiple cryptids behind 'Caddy'.

Speculating on the phylogenetic relations of 'Cryptozoological Mega-Monsters' like 'Caddy' which have highly debatable traits (Read: chimerical, poorly supported, and questionably interpreted) is far beyond the applicability of the information available. I seriously question the statistical reality of marine cryptid 'types', as reading through 'Caddy' reports in LeBlond and Bousfield (1995) reveals them to be only slightly less vague and polymorphic than the Many-Finned. And this is likely the best-supported 'type' of marine cryptid! I would strongly suggest that sea serpent 'types' should be jettisoned unless thorough qualitative and quantitative analysis suggests otherwise.

This does not mean that we should stop investigating sightings and strandings. Some of the more detailed reports can be subjected to qualitative and cladistic analysis to determine if an identity can be established. However, if somebody like Bob Pitman sees an unidentified beaked whale (which he did) and only mentions a handful of characters - considering the unambiguous relation with an extant clade and the source of the report, we can seriously propose this as a cryptid. The only way to establish that the 'Cryptozoological Mega-Monster' is out there is to wait for an unambiguous carcass to show up, and I'm sure everyone familiar with cryptozoology is aware of how that has gone so far...

References:


Cracraft, J. (2006). Why Classifications are Essential Tools for Comparative Avian Biology. Wings Without Borders: IV North American Ornithological Conference. 71. Available.


Crother, BI, et al. (2009). Giant Canadian Snakes and Forensic Phylogenetics. Contemporary Herpetology 2009(2), 1-4. Available


LeBlond, PH and Bousfield, EL. (1995). Cadborosaurus Survivor from the Deep. Horsdal and Schubart Publishers: Victoria, Canada.


Maddock L, et al. (1994). Mechanics and physiology of animal swimming. Marine Biological Association of the United Kingdom: United Kingdom. Partially Available.


Paxton, CGM. (2009). The plural of 'anecdote' can be 'data': statistical analysis of viewing distances in reports of unidentified large marine animals 1758–2000. Journal of Zoology 279(4), 381-387.


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Ais: Survivors of the Sixth Extinction

Markus Bühler of Bestiarium and I have been working on a project that has just been made public:

Ais: Survivors of the Sixth Extinction

As the web address indicates, ours is a speculative evolution project, a topic which has been most recognizably covered by the TV program The Future is Wild and the works of Dougal Dixon. Spec evolution has a rising profile and has even influenced the bestiary of Peter Jackson's King Kong and possibly Avatar. I feel that the finest example of this genre to date is The Speculative Dinosaur Project, which created a vivid and incredibly well thought-out world where the most famous extinction in history never occurred. While there have been a few spec evolution projects involving the fauna of the future, I feel that ours will be a justifiably unique take on things. I shall not discuss the scenario that has occurred, but perhaps these song lyrics will give some impression:

If there's one thing you can say

About Mankind

There's nothing kind about man

You can drive out nature with a pitch fork

But it always comes roaring back again

- Tom Waits, Misery is the River of the World

Speculating about an unspecified date in the not-too-distance future allows for our project to comment on current events. For instance, the Longsnout Copotone is a descendant of invasive Pterygoplichthys species, which proved to be an unstoppable force in the future and one of the most specious vertebrate clades ever. You might recall that I discussed the present status of those invaders here. Also of note is that marine ecosystems have incredible numbers of jellyfish controlled by highly-specialized predators. One philosophy behind this project is that the present influences of man will have lasting effects beyond quarries and removed mountain tops. At the same time, life is a remarkably resilient thing which can recover from near-apocalyptic scenarios, and the diversity of Ais will be considerably greater than the present region it is derived from. It is worth noting that one species is suspiciously absent from the landscape...

This project also intends to give animals other than mammals and birds a chance in the spotlight, as they have been cast to the side in other spec evolution projects. We will also avoid the "hey wouldn't it be neat if _____ evolved into _____ ?" type of scenario and create justifiable extrapolations. While the Longsnout Copotone appears to be a lazy example of the former, it needs to be pointed out that large loricariids are already fully capable of feeding on molluscs and crustaceans (e.g. Acanthicus adonis), so the only steps needed to evolve into a obligate-molluscivore would be an increased crushing ability, modified digestive system, and increased salt tolerance. It is worth noting that another clade of armored, benthic fishes has produced a sturgeon-like species (Podothecus accipenserinus) with actual sturgeon species already present in its region! As suggested by the common name, the Longsnout Copotone is the only species of 'molluscivorous loricariid' which is sturgeon-like, with the others having taken other approaches.


Anyways, enough cross promotion - be sure the check on Ais on the first of every month!