Ozimek volans: homology and analogy

Earlier we looked at the new protorosaur
Ozimek volans (Fig. 1) here and determined by phylogenetic analysis that it was a sister to Prolacerta, not Sharovipteryx.

Today, just a short note
about its homology with Prolacerta and its purported and invalid analogy with the unrelated membrane gliders Sharovipteryx and Cynocephalus.

Figure 1. Ozimek volans compared to its homolog sister, Prolacerta, and to two putative analogs, Sharovipteryx and Cynocephalus, all to scale. Note the lack of climbing claws and the weakness of the limbs and girdles in Ozimek.

Figure 1. Ozimek volans compared to its homolog sister, Prolacerta, and to two putative analogs, Sharovipteryx and Cynocephalus, all to scale. Note the lack of climbing claws and the weakness of the limbs and girdles in Ozimek, adorned here with hypothetical membranes.

Floating is just one niche possibility
based on the weakness of the muscle anchors in Ozimek. I have never seen such skinny arms and legs, so I am at a loss for a suitable niche for it.
I don’t see large climbing claws,
long manual digits, large muscles and their anchors on Ozimek that one finds on Cynocephalus. If it were it otherwise, I might support the gliding hypothesis.
Gliding animals need strong limbs
and muscle anchors not only for supporting their total weight in the air, but also for climbing trees and the momentum shock of both take-off and landing. In this regard, Ozimek appears to be quite a bit weaker than either Cynocephalus or Sharovipteryx. If it was like Sharovipteryx the diameter of the limb bones should have been scaled up to deal with the magnitude greater mass.
Sharovipteryx has elongate ilia and pectoral elements with short arms, plus seven sacrals, all lacking in Ozimek, its putative sister.
Sharovipteryx does not have a lateral membrane
Old and bad reconstructions of Sharovipteryx used to add a membrane between imagined long forelimbs with short fingers and the longer hind limbs. No one has ever seen such a membrane in the fossil. No sisters have such a membrane. Rather a uropatagium trails each hind limb, as in pterosaurs and Cosesaurus. Phylogenetic bracketing adds a pterosaur-like brachiopatagium behind each tiny Sharovipteryx forelimb, but it is likewise not visible in the fossil. The Dzik and Sulej team counts on the validity of the fantasy lateral membrane between the limbs to make their Ozimek a glider. But it was never there in any case.
Figure 1. Dzik and Sulej are so sure that their Ozimek was a spectacular big sister to Sharovipteryx that they gave a model gliding membranes and used the largest disassociated humerus for scale. More likely it was an aquatic animal that did not move around much underwater.

Figure 2. Dzik and Sulej are so sure that their Ozimek was a spectacular big sister to Sharovipteryx that they gave a model gliding membranes and used the largest disassociated humerus for scale. No membranes are present lateral to the pancaked ribs in Sharovipteryx and so this patagium on Ozimek, lacking such ribs, is also based on fantasy.

Prolacerta is also hollow-boned,
and is the sister of Ozimek in the LRT. No tested taxon, including Sharovipteryx, is phylogenetically closer.
Langobardisaurus analogy
Overall, Ozimek looks like a big, skinny Langobardisaurus (Fig. 3).
Figure 2. Langobardisaurus compared to Ozimek and its sister, Prolacerta.

Figure 3. Langobardisaurus compared to Ozimek and its sister, Prolacerta to scale. Structurally, Ozimek was similar to Langobardisaurus, but had much longer, weaker limbs and girdles and despite a long list of similarities, still nested with Prolacerta.

Langobardisaurus had the same long neck
and big skull as seen in Ozimek, but is not related, The girdles are larger and the limbs are more robust in the smaller Langobardisaurus than in the larger Ozimek. So, whatever Langobardisaurus was doing, Ozimek might have been doing, but more slowly, cautiously and secretly, perhaps like a spider.

Protorosaurs and Tritosaurs
appear on opposite sides of the LRT, but closely resemble one another such that macrocnemids and langobardisaurs were both considered protorosaurs (even by me) before the LRT showed macorcnemids and langobardisaurs actually nested with tritosaur lepidosaurs. The convergence is amazing and potentially confusing unless a rigorous analysis is performed. The LRT has been successful in separating such convergent taxa and continues to do so.

References
Dzik J and Sulej T 2016. An early Late Triassic long-necked reptile with a bony pectoral shield and gracile appendages. Acta Palaeontologica Polonica 61 (4): 805–823.

Splitting up the Tenrecidae

Everyone agrees
that the current list of genera within the clade Tenrecidae are a diverse lot. Asher and Hofreiter 2006 report, With the exception of a single genus of shrew (Suncus), insectivoran-grade mammals from Madagascar are members of the family TenrecidaeThis group of placental mammals consists of eight genera endemic to Madagascar and two from equatorial Africa and is remarkably diverse, occupying terrestrial, semi-arboreal, fossorial, and semiaquatic niches.” Finlay and Cooper 2015 sought to quantify that diversity. They report, “There are tenrecs which resemble shrews (Microgale tenrecs), moles (Oryzorictes tenrecs) and hedgehogs (Echinops and Setifer tenrecs). The small mammal species they resemble are absent from the island.”

Olson and Goodman 2003 report,
“Morphological studies have not support [genomic studies], however and the higher-level origins of both tenrecs and golden moles remain in dispute.” However, they limited their report to tenrecs, assuming a single origin.

According to Poux et al. 2008
Tenrecidae includes the following clades:

  1. Potamogalinae includes the genera Potamogale and Micropotamogale
  2. Tenrecinae includes the genera Tenrec, Echinops, Setifer and Hemicentetes;
  3. Oryzorictinae includes the genera Oryzorictes, Limnogale and Microgale;
  4. Geogalinae: includes Geogale. 

What makes a tenrec a tenrec?
Wikipedia provides no clue. And the academic literature has been similarly bereft. Instead all authors emphasize the diversity in this clade. The traditional and recent hypotheses of common ancestry are based on genomic studies that provide no clues to skeletal similarities and differences. As mentioned earlier, the anus and genitals revert to a single cloaca, as in golden moles and the scrotum reverts to an internal arrangement, distinct from many other mammals, but similar to odontocetes and hippos + mysticetes. The permanent dentition in tenrecs tends not to completely erupt until well after adult body size has been reached. Some tenrecids [which ones?] erupt their molars before shedding any deciduous teeth other than the third milk incisors.

Helping to define tenrecs, MacPhee 1987 reported,
“Shrew tenrecs are sometimes considered to be the most primitive members of Tenrecoidea. They outwardly resemble other unspecialized soricomorph insectivores (e.g., Crocidura) in possessing dense, rather velvety fur, abundant vibrissae, tiny eyes, short pentadactyl limbs slung under a long, fusiform body, and an elongated skull tapering into a narrow rostrum. Notably, like other tenrecs they retain ancient plesiomorphies that have been lost in virtually all other eutherian lineages (including true shrews), such as variable and rather low body temperature and cloacae in both sexes.”

Genomic analysis
by Asher and Hofreiter 2006 found Tenrecidae to be monophyletic. The proximal outgroup taxon was  Chrysospalax, a highly derived genus within the Chrysochloridae, or golden moles. In like fashion, Elephantulus, an elephant shrew, and Procavia, the hyrax, were successive outgroups as members of the Afrotheria, a diverse clade that only arises in genomic analyses and seems to provide a long list of oddly matched sister taxa.

Figure 1. Subset of the LRT highlighting tenrecs and former tenrecs

Figure 1. Subset of the LRT highlighting tenrecs and former tenrecs

By contrast
The large reptile tree (LRT, Fiig. 1) found the members of the former Tenrecidae so diverse that they nested in three different clades, apart from one another.

  1. Potamogale and Micropotamogale (both from Africa) nested with the shrew, Scutisorex within Glires.
  2. Echinops, Limnogale and Microgale (all from Madagascar) nested with the hedgehog, Erinaceus, despite lacking spines and also within Glires,
  3. Hemicentetes and Tenrec (both from Madagascar) nested with several fossil leptictids basal to odontocetes (toothed whales)  among extant taxa.

Those taxa nesting in Glires
have enlarged central incisors lacking in Hemicentetes and Tenrec, which have a longer, more pointed rostrum with relatively tiny incisors. Shifting aquatic Limnogale to nest with aquatic Potamogale adds 13 steps, so water habits are convergent.

Genomic sequencing lumps

  1. Limnogale and Microgale, as in the LRT.
  2. Micropotamogale and Potamogale, as in the LRT.
  3. Hemicentetes and Tenrec, as in the LRT.

Dissimilarities in DNA and trait-based tree topologies arise
with greater phylogenetic distance. The LRT permits one to include fossil taxa and to observe changes in traits that genomic codes can not do.

In the LRT
Hemicentetes and Tenrec are surrounded by fossil lepitictids. Asher and Hofreiter do not list odontocetes in their analysis, but these nest with Hemicentetes and Tenrec among living taxa in the LRT. Rose 1999 ran an analysis of postcranial traits that included Leptictidae and Tenrecidae. It nested Tenrecidae between Solenodon and shrews and Leptictidae between Tupaia and Zalambdalestes, distinct from the LRT which includes more characters, more body parts and more taxa. In the LRT Lepticitis and Lepticitidium nest with Andrewsarchus and Tenrec between them.

See what happens when you include more taxa? Topologies change.

Body masses of tenrecs
Finlay and Cooper 2015 report, “Body masses of tenrecs span three orders of magnitude (2.5 to >2,000 g): a greater range than all other families, and most orders, of living mammals.” The new phylogenetic set will not include the tiniest shrew tenrecs, but it will include the sperm whale weighing in at 57,000 kg.

If anyone has access to 
skeletal images of Geogale and/or Oryzorictes, please send them my way in order to add them to the LRT.

When you use molecules

  1. you don’t use traits. Therefore you lump and divide taxa based on combinations of DNA you can’t see or argue about.
  2. you don’t use fossils. Therefore you can’t tell which fossil taxa gave rise to which other fossil and extant taxa.
  3. you often recover very odd sister taxa that anti-evolutionists love to use in their PowerPoint lectures. That gives them power over audiences who want to see the evidence of evolution, which the LRT provides.

We have to own up to the shortcomings of DNA
while we still can. Great for criminals and baby daddies, bad for turtles and archosaurs. I think we need to get back to morph studies in mammal phylogeny. Molecules have given us very weird and unwieldy answers that don’t start small, extinct and simple and end large, extant and exotic, like the LRT does.

 

Authority
Granted if have not seen any specimens first hand, nor am I anywhere near a tenrec expert. Like Galileo, I am metaphorically tossing balls off the Tower of Pisa, coming to my own conclusions following repeatable observations. Because you can do that in Science. Others may argue methods and observations, but they will have to duplicate the list of taxa before they can do so with their own authority. This post provides an expanded taxon list and tentative insights for future studies.

References
Asher RJ and Hofreiter M 2006. Tenrec phylogeny and the noninvasive extraction of nuclear DNA. Systematic Biology 55(2):181-194. 
Asher RJ 2007. 
A web-database of mammalian morphology and a reanalysis of placental phylogeny. BMC Evol Biol. 7: 108-10 online
Asher  RJ and Helgen KM 2010. Nomenclature and placental mammal phylogeny. BMC Evolutionary Biology 10:102 online
Du Chaillu P 1860. Descriptions of mammals from equatorial Africa. Proceedings of the Boston Society of Natural History, 7, 358–369.
Eisenberg JF and Gould E 1970. The tenrecs: a study in mammalian behavior and evolution. Smithsonian Institution Press, Washington, DC. 138 pp. PDF online
Finlay S and Cooper N 2015. Morphological diversity in tenrecs (Afrosoricida, Tenrecidae): comparing tenrec skull diversity to their closest relatives. PeerJ 3:e927; DOI 10.7717/peerj.927
Linnaeus C 1758. Systema naturæ per regna tria naturæ, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. Tomus I. Editio decima, reformata.
MacPhee RDE 1987. The shrew tenrecs of Madagascar: systematic revision and Holocene distribution of Microgale (Tenrecidae, Insectivora).
Martin WCL 1838. On a new genus of insectivorous mammalia. Proceedings of the Zoological Socieety, London, 6:17.
Mouchaty SK, Gullberg A, Janke A, Arnason U 2000. Phylogenetic position of the Tenrecs (Mammalia: Tenrecidae) of Madagascar based on analysis of the complete mitochondrial genome sequence of Echinops telfairi. Zoologica Scripta. 2000, 29 (4): 307-317. 10.1046/j.1463-6409.2000.00045.x.
Nicoll M 1985. The biology of the giant otter shrew *Potamogale velox*. National Geographic Society Research Reports, 21: 331-337.
O’Leary, MA et al. 2013. The placental mammal ancestor and the post-K-Pg radiation of  placentals. Science 339:662-667. abstract
Olson LR and Goodman SM 2003. Phylogeny and biogeography of tenrecs. Pp. 1235-1242 in Natural History of Madagascar, SM Goodman & JP Benstead (eds.), University of Chicago Press, Chicago.
Poux C, Madsen O, JGlos J, de Jong WW and Vences M 2008. Molecular phylogeny and divergence times of Malagasy tenrecs: Influence of data partitioning and taxon sampling on dating analyses. BMC Evolutionary Biology 8:102. Open Access
Rose KD 1999. Postcranial skeleton of Eocene Leptictidae (Mammalia), and its implications for behavior and relationships. Journal of Vertebrate Paleontology 19(2):355-372.
Suárez R, Villalón A, Künzle H and Mpodozis J 2009. Transposition and Intermingling of Gαi2 and Gαo Afferences into Single Vomeronasal Glomeruli in the Madagascan Lesser Tenrec Echinops telfairi. PLoS ONE 4(11): e8005. doi:10.1371/journal.pone.0008005

 

Tenrec bones website here (Microgale and Tenrec skulls and jaws)

More evidence that Meiolania is a basal turtle

Figure 5. Meiolania, the most primitive of known turtles, has lateral forelimbs, like non turtles.

Figure 1. Meiolania, the most primitive of known turtles, has lateral forelimbs, like non turtles. Extant turtle elbows point anteriorly. 

Earlier we looked at the bizarre and seeming highly derived skulls of Meiolania (Fig. 1) and Niolamia, (Fig. 2) two large late-surviving meiolanid turtles that are only known from rather recent fossil material following an undocumented origin in the Late Permian or Early Triassic.  They both nested as sisters to Elginia (Fig. 2; Late Permian), a toothed turtle sister with horns. So the horns and frills are primitive, not derived.

Figure 2. Comparing the skulls of Elginia, with teeth, and the turtle, Niolamia, toothless.

Figure 2. Comparing the skulls of Elginia, with teeth, and the turtle, Niolamia, toothless.

Here’s a review
of various turtle ancestor candidates in graphic format (Fig. 3). A candidate touted by several recent authors, Eunotosaurus, is among those shown.

Figure 1. In traditional studies Eunotosaurus nests at the base of turtles, but that is only in the absence of the taxa shown here and correctly scored. Here Eunotosaurus is convergent with turtles, but not related. Turtles arise from small pareiasaurs.

Figure 3. In traditional studies Eunotosaurus nests at the base of turtles, but that is only in the absence of the taxa shown here and correctly scored. Here Eunotosaurus is convergent with turtles, but not related. Turtles arise from small pareiasaurs.

Cervical count
Pareiasaurs have 6 cervicals. Turtles have 8, several of which are tucked inside the shell. Proganochelys, often touted as the most basal turtle, has 8 cervicals. Horned Meiolania, at the base of the hard-shell turtles has 6 cervicals with ribs and 2 without ribs according to Gaffney (1985; Fig. 4). Most living turtles do not have cervical ribs. In Proganochelys cervical ribs are much reduced.

Note that in Odontochelys (Fig. 3 a similar situation arises where the all the vertebrae anterior to the expanded ribs are considered cervicals, even though two are posterior to the scapula. Similarly, in Proganchelys (Fig. 3) the last cervical is posterior to the scapula. In other tetrapods (let me know if I am forgetting any), all the cervicals are anterior to the scapula and a few dorsal vertebrae typically appear anterior to the scapulae. The tucking of the scapula beneath the ribs of turtles is a recurring problem with many offering insight.

Figure 1. Meiolania cervicals. Did Gaffney follow tradition when he identified 8 cervicals here? Only 6 have ribs and the shape changes between 6 and 7.

Figure 4. Meiolania cervicals. Did Gaffney follow tradition when he identified 8 cervicals here? Only 6 have ribs (yellow) and the shape changes between 6 and 7.

There are several different possible nesting sites
for turtles with regard to living reptiles (including mammals and birds, Fig. 5). Only the LRT (in yellow) has not made it to the academic literature (after several tries) because it is the only tree topology that splits Archosauromorpha from Lepidosauromorpha in the Viséan, further in the past than other workers venture to place reptiles that still look like amphibians. Until we get the basic topology down and agreed upon, it is going to be difficult to nest turtles properly.

Figure 2. Various hypotheses regarding turtle origins. The LRT is added in yellow.

Figure 5. Various hypotheses regarding turtle origins. The LRT is added in yellow. Most studies show Synapsida as the basal dichotomy, whereas the LRT divides Lepidosauromorpha from Archosauromorpha together with two separate origins for diapsid reptiles.

References
Gaffney ES 1985. The cervical and caudal vertebrae of the cryptodiran turtle, Meiolania platyceps, form the Pleistocene of Lord Howe Island, Australia. American Museum Novitates 2805:1-29.

Ozimek volans: long and skinny, but not a glider

Updated a few hours later
with a phylogenetic analysis nesting Ozimek with Prolacerta.

A new and very slender
Late Triassic (230 mya) reptile from lake sediment, Ozimek volans (Dzik and Sulej 2016; ZPAL AbIII / 2512; Figs. 1-3) appears to look like a variety of taxa on both sides of the great divide within the Reptilia: macrocnemids and protorosaurs. Based on the long, thin-walled neck bones, Ozimek was originally considered a possible pterosaur or tanystropheid, but Dzik and Sulej nested it with Sharovipteryx (Fig. 1), the Middle Triassic gliding fenestrasaur, and considered it a big glider (Fig. 3).

Figure 1. Three in situ specimens attributed to Ozimek. The largest humerus (purple) is scaled up from the smaller specimen. These are 80% of full scale when viewed at  72 dpi. To me, that 2012 ulna looks like a tibia + fibula and the 2012 humerus looks like a femur, distinct from the 2512 humerus.

Figure 1. Three in situ specimens attributed to Ozimek. The largest humerus (purple) is scaled up from the smaller specimen. These are 80% of full scale when viewed at  72 dpi. To me, that 2012 ulna looks like a tibia + fibula and the 2012 humerus looks like a femur, distinct from the 2512 humerus.

The large reptile tree
(LRT) does not nest the much larger Ozimek with tiny Sharovipteryx, but with Prolacerta (Fig. 2). While lacking an antorbital fenestra, Dzik and Sulej consider Ozimek an archosauromorph. They also consider Sharovipteryx an archosauromorph.  Like all fenestrasaurs, Sharovipteryx has an antorbital fenestra by convergence with archosauromorpha.

Figure 2. Reconstruction of Ozimek with hands and feet flipped to a standard medial digit 1 configuration and compared to Sharovipteryx and Prolacerta to scale. Note the short robust forelimbs and elongate pectoral elements of Sharovipteryx, in contrast to those in Ozimek.

Figure 2. Reconstruction of Ozimek with hands and feet flipped to a standard medial digit 1 configuration and compared to Sharovipteryx and Prolacerta to scale. Note the short robust forelimbs and elongate pectoral elements of Sharovipteryx, in contrast to those in Ozimek. Compared to Prolacerta the girdles are much smaller, indicating a much smaller muscle mass on the limbs, probably making it a poor walker. Perhaps it floated to support its weight.

Sediment
The authors report on the limestone concretion, “the fossils under study occur in the one-meter thick lacustrine horizon in the upper part where the dominant species are aquatic or semi-aquatic animals. These also include the armored aetosaur Stagonolepis, possible dinosauriform Silesaurus, crocodile-like labyrinthodont Cyclotosaurus, and the predatory rauisuchian Polonosuchus.”

Figure 1. Dzik and Sulej are so sure that their Ozimek was a spectacular big sister to Sharovipteryx that they gave a model gliding membranes and used the largest disassociated humerus for scale. More likely it was an aquatic animal that did not move around much underwater.

Figure 3. Dzik and Sulej are so sure that their Ozimek was a spectacular big sister to Sharovipteryx that they gave a model gliding membranes and used the largest disassociated humerus for scale. More likely it was an aquatic animal that did not move around much underwater due to its weak musculature. The model was built based on crappy reconstructions of Sharovipteryx.

Forelimbs
Dzik and Sulej take the word of Unwin 2000, who did not see forelimbs in Sharovipteryx (and illustrated it with Sharov’s drawing), rather than the reports of Sharov 1971, Gans et al. 1987 and Peters 2000 who did see forelimbs. The latter three authors found the  forelimbs were short with long fingers, distinct from the gracile forelimbs and short fingers found in Ozimek. So, that’s one way to twist the data to fit a preconception. New specimens often get a free pass when it comes to odd interpretations, as we’ve seen before in Yi qi and others.

Manus and pes
In the reconstruction it appears that the medial and lateral digits are flipped from standards. This is both shown and repaired in figure 2.

According to the scale bars
the ZPAL AbIII/2511 specimen is exactly half the size of the ZPAL AbIII/2012 specimen. That issue was not resolved by the SuppData  The humerus shown in the 2012 specimen is not listed in the SuppData. Even so, the authors also ally another large humerus (2028) to Ozimek, and this provides the large scale seen in the fleshed-out model built for the museum and the camera (Fig. 3).

Built on several disassociated specimens
the reconstruction of Ozimek (Fig. 2) is a chimaera, something to watch out for.

Initial attempts at a phylogenetic analysis
based on the reconstruction pointed in three different directions, including one as a sauropterygian based on the illustrated dorsal configuration of the clavicles relative to the coronoids. If the clavicles are rotated so the vernal rim is aligned with the anterior coracoids the dorsal processes line up correctly with the indentations on the scapula (Fig. 2), alleviating the phylogenetic problem.

Lifestyle and niche
Sharovipteryx has an elongate scapula and coracoid, traits lacking in Ozimek. Sharovipteryx also has an elongate ilium and deep ventral pelvis, traits lacking in Ozimek. The limbs are so slender in Ozimek, much more so than in the much smaller Sharovipteryx, that it does not seem possible that they could support the large skull, long neck and long torso in the air – or on the ground. This is a weak reptile, likely incapable of rapid or robust locomotion. So instead of gliding, or even walking, perhaps Ozimek was buoyed by still water. Perhaps it moved its spidery limbs very little based on the small size of the available pectoral and pelvic anchors for muscles, despite those long anterior caudal transverse processes. Those might have been more useful at snaking a long thin tail for propulsion.

If we use our imagination,
perhaps with a large oval membrane that extended from the base of the neck to fore imbs to hind limbs Ozimek might have been like a Triassic water lily pad, able to dip its skull beneath the surface seeking prey, propelled by a flagellum-like tail. Not sure how else to interpret this set of specimens.

References
Dzik J and Sulej T 2016. An early Late Triassic long-necked reptile with a bony pectoral shield and gracile appendages. Acta Palaeontologica Polonica 61 (4): 805–823.

wiki/Ozimek (in Polish)

The ‘hedgehog’ tenrecs: they nest with hedgehogs

This is a think piece.
You’re going to be faced with

  1. a geographically inspired return of the cloaca (proposed heresy) or
  2. MASSIVE convergence involving everything but the cloaca (current and traditional paradigm)

Arguments will be presented.
You decide which is more parsimonious. We may need to bring in the DNA guys here, and I would welcome them! I don’t think such a study involving a wide range of purported and actual tenrecs has been proposed or done yet. Let me know as I am unaware of published work on this subject.

The present problem had its genesis in whale phylogenetic studies.
Earlier, from skeletal data, the the large reptile tree (LRT) nested odontocete (toothed) whales with tenrecs and mysticete (baleen) whales with hippos and desmostylians.

However
current DNA studies do not support the tenrec – odontocete relationship — perhaps because workers used the lesser hedgehog tenrec (Echinops telfairi, Martin 1838, Figs. 2, 3) in their DNA studies. Echinops is traditionally considered a tenrec, but it may not be one based on bones (Fig. 3) and massive homology/convergence with the European hedgehog, Erinaceus (Figs. 1, 3).

Figure 4. European hedgehog, a member of Glires.

Figure 1. European hedgehog, Erinaceus, a member of Glires.

It’s the cloaca that seems to matter most
in tenrec studies. Plus the location: Madagascar.

Figur3 5. Madagascar hedgehog, is not a tenrec, but another member of Glires.

Figure 2. Madagascar hedgehog tenrec, Echinops, perhaps not a tenrec, but another member of hedgehog family within Glires.

There are two extant hedgehog tenrecs (HHTs):
the greater HHT (Setifer = Ericulus setosus) and the lesser HHT (Echinops telfari). Their skulls are not that different from each other, except in size. They have similar skeletons and spines coats. So we’ll focus on the lesser HHT as other workers have done before.

The problem is
the large reptile tree (LRT) nests Echinops rather convincingly with hedgehogs, like Erinaceus, within Glires, not with tenrecs like Tenrec (Fig. 1). Shifting Echinops to the tenrecs adds 30 steps to the LRT. Shifting the entire tenrec clade (ncluding the odontocetes) to the hedgehogs adds only 12 steps.

We’ve seen something like this before
when the purported tenrec, Potamogale (Du Chaillu 1860, Nicoll 1985; extant), the giant otter shrew that was supposed to be a tenrec, instead nested rather convincingly with shrews, far from tenrecs. It, too, has a cloaca.

Maybe it’s because they’re all from Madagascar.
Not sure what it is about that island that takes a perfectly good set of genital and anal openings and reverts them back into a single primitive cloaca. But that appears to be happening here among unrelated taxa, by convergence.

Among mammals
monotremes have a cloaca and that is most likely the primitive condition, as a cloaca is found in all other reptiles. Most marsupials separate the anus and genitals, so no cloaca is present — except in the very derived marsupial moles. Marsupials are basal to placentals according to the LRT, so any appearance of a cloaca in placentals is a reversal. Thus the Madagascar hedgehogs, the African golden moles and giant otter shrews (Potamogale) that redevelop a cloaca are examples of phylogenetic reversals.

So you  have a choice in nesting these purported tenrecs:

  1. Do you follow the bones and other soft (and prickly, Fig. 2) tissue with the exception of the cloaca?
  2. Or do you follow the cloaca alone? Current taxonomy and experts for over a century favor this choice.

To my knowledge,
mtDNA studies have not been conducted yet to resolve interrelationships among tenrecs and other mammals. If Echinops is indeed a hedgehog, then tenrecs have not been genetically tested against odontocetes. In fact, tell me if I’m wrong, but this may be the first time such a study has been conducted on morphology alone. Asher and Hofreiter 2006 stated at the time: “Due in part to scarcity of material, no published study has yet cladistically addressed the systematics of living and fossil Tenrecidae (Mammalia, Afrotheria).”

Echinops was employed by Mouchaty et al. 2000. Echinops might have been used by Meredith 2011 and Song 2012 to nest tenrecs with golden moles (Chrysocloris) as Afrotheres, related to elephants (Elephas) and hyraxes (Procavia). I don’t see any other tenrecs being used in molecular studies.

Echinops was recently employed by
Suarez 2009 in a study of the vomernasal system (VNS). The distribution of both vomernasal pathways in Eutheria was found to be present in rodents and Echinops, but not in other tested eutherians, none of which included other tenrecs. Of course, hedgehogs nest with rodents in the LRT.

Figure 1. The skulls of Erinaceus (above), Echinops (middle) and Tenrec (below), compared. Note the large premaxillary teeth common to all members of the Glires to the exclusion of other clades, including Tenrecidae.

Figure 3. The skulls of Erinaceus (above), Echinops (middle) and Tenrec (below), compared. Note the large premaxillary teeth common to all members of the Glires to the exclusion of other clades, including Tenrecidae. The anterior maxillary tooth of Erinaceus might be a canine, but it is not at the anterior rim of the maxilla, where one expects a canine.

Let’s compare
a hedgehog, a tenrec and the lesser hedgehog tenrec and perhaps you’ll see that a mistake was made over 100 years ago that continues to adversely affect phylogenetic analyses today. Perhaps a member of Glires has been long considered a member of Tenrecidae by virtue of its location, Madagascar, and its cloaca.

The European hedgehog
Erinaceus europaeus (Linneaus 1758; 20-30cm; extant) this omnivore can roll itself into a ball, erecting its spines for defence. Unlike most Glires, the hedgehog does not have a diastema. The jugal is very tiny in this clade.

The lesser hedgehog tenrec
Echinops telfairi (Martin 1838; extant, 13-17 cm) the lesser or pygmy hedgehog tenrec is widely considered a tenrec, but here it nests with hedgehogs and other Glires including rodents. This omnivore is restricted to Madagascar, home of severalt tenrecs. Note the large canines, like tenrecs and unlike hedgehogs. Note the large premaxillary teeth, like hedgehogs and unlike tenrecs. Unlike tenrecs, the ears are prominent. Like tenrecs, the jugal is absent.

Given that the Madagascar mammals with a cloaca
all do some burrowing, I wonder if the genitals and anus retreated beneath the cover of a single opening in order to keep dirt out? If that’s not the answer, I wonder what the common thread is that these unrelated taxa have that caused that primitive trait to reappear? And I wonder if there are any analyses based on morphology that include several tenrecs and other eutherians for comparison? So far I have found none, so the LRT is shedding light where it may be needed.

If Echinops is indeed a hedgehog with a cloaca
then we have to go get some mtDNA from Tenrec to see if it is a good match for odontocete mtDNA. At present, Tenrec has not been tested for its mtDNA, that I know of, so the whale connection question remains open.

While we’re at it it
count the stomachs in Tenrec. Even odontocetes have subdivided stomachs. Let’s find out when that trait appeared.

References
Asher RJ 2007. A web-database of mammalian morphology and a reanalysis of placental phylogeny. BMC Evol Biol. 7: 108-10 online
Asher  RJ and Helgen KM 2010. Nomenclature and placental mammal phylogeny. BMC Evolutionary Biology 10:102 online
Du Chaillu P 1860. Descriptions of mammals from equatorial Africa. Proceedings of the Boston Society of Natural History, 7, 358–369.
Eisenberg JF and Gould E 1970. The tenrecs: a study in mammalian behavior and evolution. Smithsonian Institution Press, Washington, DC. 138 pp. PDF online
Linnaeus C 1758. Systema naturæ per regna tria naturæ, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. Tomus I. Editio decima, reformata.
Martin WCL 1838. On a new genus of insectivorous mammalia. Proceedings of the Zoological Socieety, London, 6:17.
Mouchaty SK, Gullberg A, Janke A, Arnason U 2000. Phylogenetic position of the Tenrecs (Mammalia: Tenrecidae) of Madagascar based on analysis of the complete mitochondrial genome sequence of Echinops telfairi. Zoologica Scripta. 2000, 29 (4): 307-317. 10.1046/j.1463-6409.2000.00045.x.
Nicoll M 1985. The biology of the giant otter shrew *Potamogale velox*. National Geographic Society Research Reports, 21: 331-337.
O’Leary, MA et al. 2013. The placental mammal ancestor and the post-K-Pg radiation of  placentals. Science 339:662-667. abstract
Suárez R, Villalón A, Künzle H and Mpodozis J 2009. Transposition and Intermingling of Gαi2 and Gαo Afferences into Single Vomeronasal Glomeruli in the Madagascan Lesser Tenrec Echinops telfairi. PLoS ONE 4(11): e8005. doi:10.1371/journal.pone.0008005

Dr. David Unwin on pterosaur reproduction – YouTube

Dr. David Unwin’ talk on pterosaur reproduction 
was recorded at the XIV Annual Meeting of the European Association of Vertebrate Palaeontologists, Teylers Museum, Haarlem, Netherlands and are online as a YouTube video.
Dr. Unwin is an excellent and engaging speaker.
However, some of the issues Dr. Unwin raises have been solved at www.ReptileEvolution.com
The virtual lack of calcite in pterosaur eggs were compared to lepidosaurs by Dr. Unwin, because pterosaurs ARE lepidosaurs.  See: www.ReptileEvolution.com/reptile-tree.htm
Lepidosaurs carry their eggs internally much longer than archosaurs, some to the point of live birth or hatching within hours of egg laying. Given this, pterosaurs did not have to bury their eggs where hatchlings would risk damaging their fragile membranes while digging out. Rather mothers carried them until hatching. The Mrs. T external egg was prematurely expelled at death, thus the embryo was poorly ossified and small.
Dr. Unwin ignores the fact that hatchlings and juveniles had adult proportions as demonstrated by growth series in Zhejiangopterus, Pterodaustro and all others, like the JZMP embryo (with adult ornithocheirid proportions) and the IVPP embryo (with adult anurognathid proportions).
Dr. Unwin also holds to the disproved assumption that all Solnhofen sparrow- to hummingbird-sized pterosaurs were juveniles or hatchlings distinct from any adult in the strata. So they can’t be juveniles (see above). Rather these have been demonstrated to be phylogenetically miniaturized adults and transitional taxa linking larger long-tailed dorygnathid and scaphognathid ancestors to larger short-tailed pterodactyloid-grade descendants, as shown at: www.ReptileEvolution.com/MPUM6009-3.htm
Thus the BMNH 42736 specimen and Ningchengopterus are adults, not hatchlings. And the small Rhamphorhynchus specimens are also small adults.

More turtles with temporal fenestrae

Everyone knows that turtles are supposed to be ‘anapsids’.
In other words, they aren’t supposed to have temporal fenestrae. However, many extant taxa, like the box turtle, Terrapene, have such extensive posttemporal fenestrae that the entire posterior half of the skull can be greatly eroded as it is refilled with large jaw muscles.

Figure 1. Meiolania has a lateral temporal fenestra created by more bone encircling the tympanum (ear drum) at the quadrate. It could be that the top of the qj is actually the fused sq.

Figure 1. Meiolania has a lateral temporal fenestra created by more bone encircling the tympanum (ear drum) at the quadrate. It could be that the top of the qj is actually the fused sq.

Sometimes more bone makes a fenestra
Earlier we looked at Meiolania a basal turtle with an unusual lateral temporal fenestra created by MORE BONE that encircled the eardrum and quadrate.

The extant leatherback,
Dermochelys (Fig. 2) also has a lateral temporal fenestra, but it lacks a lateral temporal bar. Dermochelys nests with Santanachelys, rather than Chelonia. Neither share this trait, nor do any other tested turtles.

Figure 1. Dermochelys, the leatherback turtle, has a lateral temporal fenestra, a product of bone reduction between the jugal and squamosal + quadrate. Adult at left, juvenile at right, not to scale. The elongate premaxilla is convergent with soft-shell turtles. Note the ontogenetic changes here. Pretty remarkable.

Figure 1. Dermochelys, the leatherback turtle, has a lateral temporal fenestra, a product of bone reduction between the jugal and squamosal + quadrate. Adult at left, juvenile at right, not to scale. The elongate premaxilla is convergent with soft-shell turtles. Note the ontogenetic changes here. Pretty remarkable.

It’s interesting
to see the ontogenetic changes that take place in the skull bones of the juvenile Dermochelys as it matures. The lateral temporal fenestra appears to enlarge with age. Other bones change their shape as the turtle matures.

Figure 2. Chelus frmbiata, the mata-mata has a temporal fenestra. Not sure if it's a lateral or upper type. Note also the mistake made by Dr. Gaffney in overlooking the squamosal and quadratojugal, and mislabeling the supratemporal.

Figure 2. Chelus frmbiata, the mata-mata has a temporal fenestra. Not sure if it’s a lateral or upper type and I”m not looking, this time, at the hole leading into the quadrate. Just in front of those projections in dorsal view you’ll see the temporal fenestra of Chelus. Note the mistake made by Dr. Gaffney in overlooking the squamosal and quadratojugal (light green and yellow) while mislabeling the supratemporal (orange). The blue bones in ventral view are all hyoids used to anchor muscles that greatly expand the throat during prey capture.  Left image from Digimorph.org and used with permission. Right image from Gaffney 1979.

Another turtle with a lateral temporal fenestra
is Chelus frimbriata, otherwise known as the Mata-mata (Fig. 2), a side-neck turtle (pleurodire) with huge hyoids that help its neck expand quickly to suck in swimming prey items. This skull also qualifies for a top-ten position among the weirdest of all reptile skulls.

Dr. Eugene Gaffney, AMNH,
the dean of all turtle studies, unfortunately overlooked the squamosal and quadratojugal in Chelus (Fig. 2) while mislabeling the supratemporal in this and all other turtles he worked on (Fig. 3). That bone is typically very large in pareiasaurs and that mislabeling is likely one reason why some turtle workers are not recognizing the one and only valid pareiasaur – turtle relationship.

Here’s another example of the same mistake. 

Figure 3. This GIF movie of two frames changes every 5 seconds. Note the caption Dr. Gaffney provides as he misidentifies the supratemporal as the squamosal. The right side of the specimen, not illustrated, 

Figure 3. This GIF movie of two frames changes every 5 seconds. Note the caption Dr. Gaffney provides as he misidentifies the supratemporal as the squamosal. The right side of the specimen, not illustrated, could represent a loss or, more likely fusion of the squomosal and quadratojugal cheekbones. Image from Gaffney 1979.

Pelomedusa
(Fig. 3) is a more plesiomorphic (basal) side-neck turtle without a lateral temporal fenestra and a very deep post-temporal fenestra. But note the ventral emargination in the cheek region. Gaffney noted the extra bone, but because he had already mislabeled the squamosal, he didn’t recognize the combination of the squamosal and quadratojugal in the cheek.

And speaking of pleurodires
(side-neck turtles), most traditional studies find a basal split between pleurodires and cryptodires (vertical neck flexure). By contrast, the LRT splits hard, dome-shelled turtles from flatter, soft-shelled turtles by the Triassic. Proganochelys represents the former while Odontochelys represents the latter. And each has their own small pareiasaur ancestor. So turtles are diphyletic, but the two clades are closely related.

References
Gaffney ES 1979. Comparative cranial morphology of recent and fossil turtles. Bulletin of the American Museum of Natural History 164(2):65-376.

wiki/Dermochelys
wiki/Chelus
wiki/Pelomedusa