Mousebirds (genus: Urocolius)

Yesterday we looked at the hoopoe (genus: Upupa)
famous for its head crest of elevating feathers. Today we look at its sister, the mousebird (genus: Urocolius) which has a similar feathery crest, but differs in having a short parrot-like beak, a long parrot-like tail and a rare parrot-like reversible toe 4. These nest between toucans + hornbills and barbets + tropicbirds. These birds share a deep maxilla with a relatively elevated jugal (Fig. 1).

Figure 1. Urocolius, the blue-napes mousebird, converges with parrots in having a reversible toe 4, the ability to feed upside-down and having a short, deep, hooked beak...plus that long parrot-like tail!

Figure 1. Urocolius, the blue-napes mousebird, converges with parrots in having a reversible toe 4, the ability to feed upside-down and having a short, deep, hooked beak…plus that long parrot-like tail! The pygostyle is missing from this specimen.

Urocolius macrourus (Bonaparte 1854; 10cm snout-vent length) is the extant blue-naped mousebird, a member of the Coliiformers. Note the deep maxilla compared to the jugal. It nests with the hoopoe in the large reptile tree between hornbills and barbets. An omniovore restricted to sub-Saharan Africa, mousebirds build nests. They are gregarious, acrobatic and scurry through the leaves like rodents. Reversible toe 4 is able to rotate posteriorly, as in the related toucan, Pteroglossus.

References
Bonaparte CL 1854. En Ateneo Italiano. 1854. 2: 313.
wiki/Urocolius
wiki/Mousebird

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The hoopoe (genus: Upupa) joins the LRT

And so does the mousebird, Colius.
They nest together between hornbills + toucans and barbets + tropicbirds.

Figure 1. Hoopoe (genus: Upupa) in vivo and as a skeleton.

Figure 1. Hoopoe (genus: Upupa) in vivo and as a skeleton.

First bird watchers thought the hoopoe was a kingfisher relative.
Then it was nested with barbets, which is where the large reptile tree (LRT, 1288 taxa) nests the hoopoe, famous for its head crest of mobile feathers.

Using DNA
Prum et al. 2015 nests all the barbets, hornbills, hoopoes, toucans and mousebirds together. And so does the LRT! The only difference is, Prum et al. split mousebirds off first, toucans last. The untenable outgroup for mousebirds and kin includes owls, vultures and the hoatzin in order of increasing distance.

Using skeletal traits
the outgroups for the extant taxa listed above are fossil specimens, Septencoracias and Cyrilavis. Owls nest with predator birds, nowhere near this clade.

Not well publicized,
the hoopoe skull appears to have four nostrils (Fig. 2). The anterior two are operative, while the posterior two are novel fenestrae opening dorsally.

Figure 1. Upupa skull in the three views. Pink arrows point to nares and fenestrae.

Figure 1. Upupa skull in the three views. Pink arrows point to nares and fenestrae.

Upupa epops (Linneaus 1758) is the extant hoopoe. It nests with mousebirds in the large reptile tree. According to Wikipedia: “The hoopoe has two basic requirements of its habitat: bare or lightly vegetated ground on which to forage and vertical surfaces with cavities in which to nest.”

Figure 3. Hoopoe skull superimposed on a specimen showing alignment of the nares, orbit and rostral tip. The rest is feathers.

Figure 3. Hoopoe skull superimposed on a specimen showing alignment of the nares, orbit and rostral tip. The rest is feathers.

We’ll look at mousebirds tomorrow.

References
Linnaeus C 1758. Systema naturæ per regna tria naturæ, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. Tomus I. Editio decima, reformata.

Not even an elevated Dimetrodon made these Dimetropus tracks

Matching tracks to trackmakers
can only ever be a semi-rewarding experience. Estimates and exclusions can be advanced. Exact matches are harder to come by. This is due to both the vagaries and varieties of sequential footprints in mud or sand, and to the rarity of having skeletal data that matches.

Figure 1. Dimetrodon adult, juvenile, skull, manus, pes.

Figure 1. Dimetrodon adult, juvenile, skull, manus, pes. Note the asymmetry of the fingers and toes. Dimetropus tracks were named for this taxon.

Which brings us to Dimetropus
Traditionally Early Permian Dimetropus tracks (Fig. 2–8; Romer and Price 1940) have been matched to the coeval pelycosaur, Dimetrodon (Fig. 1)—but only by narrowing the gauge of the Dimetrodon feet and elevating the belly off the surface, as Hunt and Lucas 1998 showed.

Today we’ll take a look at some other solutions
not involving Dimetrodon doing high-rise pushups. Several distinctly different tracks have fallen into the Dimetropus wastebasket. Let’s look at three ichnospecimens.

Traditionally, and according to Wikipedia,
citing Hunt and Lucas 1998: “Trackways called Dimetropus (“Dimetrodon foot”) that match the foot configuration of large sphenacodontids show animals walking with their limbs brought under the body for a narrow, semi-erect gait without tail or belly drag marks. Such clear evidence for a more efficient upright posture suggests that important details about the anatomy and locomotion of Sphenacodon and Dimetrodon may not be fully understood.” Hunt and Lucas blamed traditional reconstructions of Dimetrodon for the mismatch. Instead they should have looked at other candidate trackmakers from the Early Permian. Note the asymmetric manus and pes of Dimetrodon (Fig. 1). Those don’t match the tracks no matter how high the belly is above the substrate. Dimetrodon is just fine the way it is.

Figure 1. Early Permian Dimetropus tracks matched to Middle Triassic Sclerosaurus, one of the few turtle-lineage pareiasaurs for which hands and feet are known.

Figure 2. Early Permian Dimetropus tracks matched to Middle Triassic Sclerosaurus, one of the few turtle-lineage pareiasaurs for which hands and feet are known.

A better match
can be made to the Middle Triassic pre-softshell turtle pareiasaur, Sclerosaurus (Fig. 2). Note the symmetric manus and pes like those of living turtles (Fig. 3) and the Dimetropus specimen in figure 2.

Figure 2. Snapping turtle tracks in mud. Note the relatively narrow gauge and symmetric imprints.

Figure 3. Snapping turtle tracks in mud. Note the relatively narrow gauge and symmetric imprints like those of Dimetropus.

Living turtle tracks
like those of the snapping turtle, Macrochelys (Fig. 3) are also symmetrical and surprisingly narrow gauge. Let’s not forget, Dimetropus tracks occur in Early Permian sediments, predating the earliest fossil turtles, like Proganochelys, first appearing in the Late Triassic. Let’s also not forget, in the large reptile tree (LRT, subset Fig. 7) Proganochelys is not the most basal turtle and valid predecessors (not eunotosaurs) had similar hands and feet.

FIgure 4. Dimetropus tracks compared to a large Dimetrodon matched to finger and toe tips. Hand too wide. Compared to a small Dimetrodon. Hand too small. Compared to a normal size Hipposaurus, good match even if not all the digits are known.

FIgure 4. Dimetropus tracks compared to a large Dimetrodon matched to finger and toe tips. Hand too wide. Compared to a small Dimetrodon. Hand too small. Compared to a normal size Hipposaurus, good match even if not all the digits are known.

A second set of Dimetropus tracks
(Fig. 4, right), have distinctive heels behind symmetric + asymmetric imprints. A large Dimetrodon could not have made these tracks because they are too narrow. A small Dimetrodon had extremities that were too small, as the animated GIF shows.

FIgure 3. Hipposaurus compared Dimetropus. The overall and leg length is right, as are many of the digits. Unfortunately the medial digits are too short in Hipposaurus. Hipposaurus has a narrower gauge and lifted its belly of the ground, as did the Dimetropus trackmaker.

FIgure 5. Hipposaurus compared Dimetropus. The overall and leg length is right, as are many of the digits. Unfortunately the medial digits are too short in Hipposaurus. Hipposaurus has a narrower gauge and lifted its belly of the ground, as did the Dimetropus trackmaker.

Fortunately,
we also have Middle Permian basal therapsid, Hipposaurus (Figs. 4, 5), a close relative of the last common ancestor of all pelycosaurs (see Haptodus and Pantelosaurus; Fig. 6). No doubt Hipposaurus elevated its torso on a narrow gauge track, with manus tracks slightly wider than pedal traces, as in Dimetropus. Both the carpus and tarsus are elongate, matching Dimetropus tracks.

Unfortunately,
we don’t have all the phalanges for the Hipposaurus manus and pes (Fig. 4). Drag marks can lengthen a digit trace. Flexing a claw into the substrate can shorten a digit trace. It is also important to note that during the last moment of the manus propulsion phase, the medial and lateral metacarpals can rotate axially, creating the impression of an ‘opposable thumb’ in the substrate. Note that no two ichnites are identical, despite being made one after another by the same animal.

Figure 5. Closeup of Hipposaurus manus and pes compared to random Dimetropus manus and pes tracks. Note, some digits remain unknown. Some digits might create drag marks. Others may dig in a claw or two apparently shortening the digit imprint.

Figure 6. Closeup of Hipposaurus manus and pes compared to random Dimetropus manus and pes tracks. Note, some digits remain unknown. Some digits might create drag marks. Others may dig in a claw or two apparently shortening the digit imprint.

At present
a more primitive sister to Hipposaurus is the best match for the Hunt et al. 1995 Dimetropus tracks and the Early Permian timing is right.

FIgure 6. Subset of the LRT focusing on Hipposaurus and its relatives, color coded to time.

FIgure 7. Subset of the LRT focusing on Hipposaurus and its relatives, color coded to time. Hipposaurus is nearly Early Permian and probably had its genesis in the Early Permian.

In the popular press
NewScientist.com reported, “We’ve drawn iconic sail-wearing Dimetrodon wrong for 100 years. Some palaeontologists did offer an explanation – that Dimetrodon thrashed its spine from side to side so much as it walked that it could leave narrow sets of footprints despite having sprawled legs.” That hypothesis, based on omitting pertinent taxa, is no longer necessary or valid.

Abbott, Sues and Lockwood 2017 reported the limbs of Dimetrodon were morphologically closest to those of the extant Caiman, which sits on its belly, but also rises when it walks.

It is unfortunate that no prior workers considered Hipposaurus, a nearly coeval taxon with Dimetropus having matching slender digits, long legs, an erect carriage, and just about the right digit proportions.

A third ichnotaxon,
Dimetropus osageorum (Sacchi et al. 2014), was considered a possible caseid, rather than a sphenacodontid, but caseids have more asymmetric digits (= a shorter digit 2). Unfortunately, taxon exclusion also hampered the Sacchi et al. study. They did not consider Early Permian stephanospondylids, Late Permian pareiasaurs in the turtle lineage and Triassic turtles. No skeletal taxon is a perfect match for this ichnotaxon, but the Late Cretaceous turtle, Mongolochelys, is close  (Fig. 8). It took some 200 million years after the trackmaker of Dimetropus for the lateral pedal digits to shrink, but everything else is a pretty good match.

Figure 7. Dimetropus oageorum from Sacchi et al. 2014 matched to Mongolochelys, a Late Cretaceous turtle. Only pareiasaurs and turtles, among basal taxa, have such a long manual and pedal digit 2.

Figure 8. Dimetropus oageorum from Sacchi et al. 2014 matched to Mongolochelys, a Late Cretaceous turtle. Only pareiasaurs and turtles, among basal taxa, have such a long manual and pedal digit 2. The reduction of pedal digits 4 and 5 are derived in this late surviving basal turtle.

Also compare the hands and feet
of Early Permian Dimetropus osageorum (Fig. 8) to the Middle Triassic Sclerosaurus (Fig. 2). Dimetropus is solid evidence that turtle-ancestor pareiasaurs were present in the Early Permian (see Stephanospondylus, an Early Permian turtle and pareiasaur ancestor).

Saachi et al. conclude, “At the same time, the process of attributing ichnotaxa, on the basis of well preserved tracks and by comparison with known skeletal remains, is validated.”  True. Unfortunately all prior workers overlooked a wider gamut of skeletal taxa to compare with their ichnotaxon in their search for a ‘best match.’ Perhaps they felt restricted by time (Early Permian). As the above notes demonstrate, that is not a good excuse.

References
Abbott CP, Sues H-D and Lockwood R 2017. The Dimetrodon dilemma: reassessing posture in sphenacodonts. GSA annual meeting in Seattle, WA USA 2017. DOI: 10.1130/abs/2017AM-307190
Hunt AP and Lucas SG 1998. Vertebrate tracks and the myth of the belly-dragging, tail-dragging tetrapods of the Late Paleozoic. Bulletin New Mexico Museum of Natural History and Science. 271: 67–69.
Peters D 2011. A Catalog of Pterosaur Pedes for Trackmaker Identification. Ichnos 18(2):114-141. http://dx.doi.org/10.1080/10420940.2011.573605
Romano M, Citton P and Nicosia U 2015. Corroborating trackmaker identification through footprint functional analysis: the case study of Ichniotherium and Dimetropus. Lethaia https://doi.org/10.1111/let.12136
Romer AS and Price LI 1940. Review of the Pelycosauria: Geological Society of America, Special Paper 28:538pp
Sacchi E, Cifelli R, Citton P, Nicosia U and Romano M 2014. Dimetropus osageorum n. isp. from the Early Permian of Oklahoma (USA): A trace and its trackmaker. Ichnos 21(3):175–192. https://doi.org/10.1080/10420940.2014.933070

Sauropods as neotenous prosauropods

In the course of dinosaur evolution
sauropods reverted to quadrupedal locomotion, a trait found in embryo prosauropods, like Massospondylus, Fig. 1), but not in adult prosauropods or their dinosaurian ancestors.

FIgure 1. Massospondylus embryo in situ and reconstructed.

FIgure 1. Massospondylus embryo in situ and reconstructed.

This topic came to mind after seeing the new paper
on the Early Jurassic basal saurpodiform, Yizhousaurus (Zhang et al. 2018, which appears to remain bipedal as an adult; Fig. 2).

Notably, and despite it’s bipedal appearance,
in the large reptile tree (LRT, 1286 taxa), Yizhousaurus nests with the embryo Massospondylus (Fig. 1), not the adult (Fig. 4). Hence the title of this blogpost.

Figure 1. Yizhousaurus is an early Jurassic basal sauropod.

Figure 2. Yizhousaurus the early Jurassic basal sauropod that currently nests with the embryo Massospondylus.

Yes, the skeleton of Yizhousaurus
has much longer hind limbs than front limbs, which shows that the transition to a quadrupedal locomotion was gradual in adults, but the skull has several sauropod traits and the manual digit 1 ungual is no longer a big hook, but a stub, like the other manual unguals.

Figure 2. Skull of Yizhousaurus in several views.

Figure 3. Skull of Yizhousaurus in several views.

Sauropods like Yizhousaurus had their genesis
in the Early Jurassic and their greatest radiation in the Late Jurassic. Some clades extended to the Late Cretaceous.

FIgure 4. Massospondylus adult in situ.

FIgure 4. Massospondylus adult in situ.

Did sauropods have several or a single origin?
I have no idea, but the idea is already floating around out there.

References
Barrett PM 2009. A new basal sauropodomorph dinosaur from the upper Elliot formation (Lower Jurassic) of South Africa. Journal of Vertebrate Paleontology 29(4):1032-1045.
Carrano MT 2005.The evolution of sauropod locomotion: morphological diversity of a secondarily quadrupedal radiation.” in The Sauropods: Evolution and Paleobiology, edited by Curry Rogers, K. A. and Wilson, J. A., 229–251. University of California Press.
Morris J 1843. A Catalogue of British Fossils. British Museum, London, 222 pp.
Reisz RR, Scott D; Sues H-D, Evans DC and Raath MA 2005. Embryos of an Early Jurassic prosauropod dinosaur and their evolutionary significance. Science. 309(5735): 761–764.
Reisz RR, Evans DC, Roberts EM, Sues H-D and Yates AM 2012. Oldest known dinosaurian nesting site and reproductive biology of the Early Jurassic sauropodomorph Massospondylus PDF. Proceedings of the National Academy of Sciences of the United States of America. 109(7): 2428–2433.
Riley H and Stutchbury S 1836. A description of various fossil remains of three distinct saurian animals discovered in the autumn of 1834, in the Magnesian Conglomerate on Durdham Down, near Bristol. Proceedings of the Geological Society of London 2:397-399.
Zhang Q-N, You H-K, Wang T and Chatterjee S 2018. A new sauropodiform dinosaur with a ‘sauropodan’ skull from the Lower Jurassic Lufeng Formation of Yunnan Province, China. Nature.com/scientificreports 8:13464 | DOI:10.1038/s41598-018-31874-9

wiki/Massospondylus
wiki/Yizhousaurus

Convergent anterior shifts of the zygomatic arch in Glires

Something  a little strange in the course of mammal evolution here.
The temporal region of rodents (Fig. 1) appears to ‘break the rules’, but on further examination merely bends them.

We’re used to seeing
the orbit separate from the temporal fenestra, as in most reptiles, but it is a little disconcerting to see them confluent, as in most mammals, knowing that the eyeball and temporal muscle share the same opening without division.

In some rodents,
like the capybara (genus: Hydrochoerus) (Fig. 1), the lateral temporal arch (aka: zygomatic arch) drifts/shifts so far forward that it moves anterior to the temporal region and just borders the orbit (or so it seems).

Actually
the temporal jaw muscle continues to dive inside the temporal arch to the coronoid process of the dentary (= mandible). The difference is the temporal muscle in capybaras pulls at an angle over the valley created by the squamosal (Fig. 1, lower right).

FIgure 3. Hydrochoerus the capybara. At lower right, large jaw muscles are illustrated.

FIgure1. Hydrochoerus the capybara. At lower right, large jaw muscles are illustrated. The temporalis muscle (light red) anchors on the temple and inserts on the coronoid process as usual, just angled much closer to the eyeball to maintain these contacts. In dorsal view the zygomatic arch is located anterior to the temporal region of the skull here.

In other words,
the zygomatic arch (maxilla + jugal + squamosal bar) in the capybara and several other rodents and their allies (Fig. 3) does not extend to the posterior skull, as it does in basal tetrapods and most mammals, including multituberculates (Fig. 3). Even so, the temporalis muscle (Fig. 1, light red) always anchors on the temple and inserts on the coronoid process. In the capybara the temporal muscle inserts much closer to the eyeball.

Rodents have a loose jaw joint
(Fig. 2) that permits the mandible to move freely (not restricted by an axle and shaft as in Carnivora) within a muscular sling to alternately gnaw with incisors in one position, then grind with the molars in another. Primates, including humans, are similar in this regard. The alignment of the teeth can shift because the axis of rotation is loose.

Figure 3. Xianshou animation showing the loose jaw joint permitting both gnawing and grinding.

Figure 2. Xianshou animation showing the loose jaw joint permitting both gnawing and grinding. The zygomatic arch is shifted slightly anteriorly here, distinct from sister taxa (Fig. 3). If the jugal is still present, it is located as a vestigial patch on the inner rim of the zygomatic arch, as in sister taxa. This is obviously a highly derived skull and it nests at a highly derived node, contra the present paradigm and despite its early Late Jurassic appearance in the fossil record.

Cox et al. 2012 report,
“The masticatory musculature of rodents has evolved to enable both gnawing at the incisors and chewing at the molars. In particular, the masseter muscle is highly specialised, having extended anteriorly to originate from the rostrum. All living rodents have achieved this masseteric expansion in one of three ways, known as the sciuromorph, hystricomorph and myomorph conditions. Our results show that the morphology of the skull and masticatory muscles have allowed squirrels to specialise as gnawers and guinea pigs as chewers, but that rats are high-performance generalists, which helps explain their overwhelming success as a group.”

Other groups not traditionally associated with rodents,
but nest with rodents in the large reptile tree (LRT, 1281 taxa) include:

  1. The aye-aye (genus: Daubentonia) possesses large, ever-growing incisors, which it uses to gnaw wood and to access the subsurface larvae it locates through tapping. This feature of ever-growing teeth was once considered unique among primates (Simons 1995), but the aye-aye is not a primate in the LRT. Daubentonia also uses its rodent-like teeth to gnaw at nuts and hard-shelled fruits (Sterling et al. 1994, Sterling 1994b). In the LRT, Daubentonia is not a primate, but a rodent, explaining all of the above issues.
  2. The Multituberculata and Haramiyida, also posses large presumably ever-growing incisors, which they presumably use as rodents use these teeth.
  3. Maiopatagium was originally considered a haramiyid, but here nests with porcupines.

Typically the auditory bulla becomes larger
as the zygomatic arch advances forward, thus filling the vacated space below the temples. This happened several times by convergence. I wonder if that was the driving force: improved hearing for predator avoidance and/or prey detection, that made this happen in the following taxa and their kin.

  1. Scutisorex (shrews)
  2. Chrysochloris (golden moles)
  3. Macroscelides (one type of elephant shrew not related to the other type.)
  4. Solenodon 
  5. Gomphos (rabbits)
  6. Coendou (porcupines) and maybe Maiopatagium (back of skull missing)
  7. Heterocephalus (naked mole rats)
Figure 2. A selection of taxa from figure 1 more or less to scale and in phylogenetic order (pink arrows). Hope this helps with the concept of a gradual accumulation of traits. The hedgehogs Erinaceus and Echinops are transitional to the higher taxa with teeth and without.

Figure 3. A selection of taxa from figure 1 more or less to scale and in phylogenetic order (pink arrows). The hedgehogs Erinaceus and Echinops are transitional to the higher taxa with a complete arcade of teeth and without. Today, please note the posterior anchor of the squamosal (zygomatic arch).

I wonder if multituberculates are no longer with us
because they could not hear as well, based on their smaller auditory apparatus? Good question…

References
Cox et al. 2012. Functional evolution of the feeding system in rodents. PloS One 7(4): e36299. Online here.
Simons EL 1995. History, anatomy, subfossil record and management of Daubentonia Madagascariensis. In: Alterman L, Doyle GA, Izard MK. Creatures of the dark: the nocturnal prosimians. New York: Plenum Pr. p133-140.
Sterling EJ, Dierenfeld ES, Ashbourne CJ, Feistner ATC 1994. Dietary intake, food composition and nutrient intake in wild and captive populations of Daubentonia madagascariensis. Folia Primatol 62(1-3):115-24.
Sterling E 1994b. Ayes-ayes: Specialists on structurally defended resources. Folia Primatologica 62:142-154.

http://pin.primate.wisc.edu/factsheets/entry/aye-aye

Unfavorable mention on a Joe Rogan podcast two years ago

About two years ago
paleontologist, Trevor Valle, appeared on a Joe Rogan podcast (link here and below) entitled “Paleontologist Trevor Valle Debunks ‘Dinosaurs Never Existed’ Conspiracy.” Between 4:30 and 6:30 minutes into the podcast Valle said several things about me and this webpage that are not true. See below.

The following is a copy of the email
I sent to Trevor Valle. Another copy went into the comments section of the Joe Rogan podcast about 8pm CDT, September 9, 2018. Evidently there’s a jungle of misunderstanding out there that needs to be trimmed back.


Hi Dr. Valle:

I just saw your YouTube video on the Joe Rogan podcast.

You said a few things about me (I am David Peters) that are not true.

1. “He’s a jackass.” We’ve never met.

2. “All reptiles are mammals.” Actually just the opposite. All mammals are reptiles (= amniotes, under the new tetrapod family tree that minimizes taxon exclusion, see below). I hope you just had a memory lapse and misspoke and that you did check the site out first and not just rely on hear-say.

3. “All of these clades should be in this…and all of this crap” The new tetrapod family tree has a magnitude more included taxa than any prior study. Some taxa not previously tested together now nest together. Since this is science, anyone can duplicate the study using a similar list of taxa/specimens and their own list of character traits. I encourage everyone interested to do so. Note: DNA studies are widely known not to duplicate trait studies, and the new tetrapod family tree is similar to other trait studies in that regard. Here, birds still nest with birds, snakes with snakes, etc. So there are broad areas of agreement with past studies. Importantly, every branch of the tree shows a gradual accumulation of traits that appears to mirror actual evolutionary pathways. Some do break paradigms and traditions. Also note, whenever taxa have been tested together later by other workers, as in Chilesaurus, Diandongosuchus, Lagerpeton and others, their results confirm the earlier results recovered here.

4. “He wholesale copied from a colleague of mine, posted it, which is a violation of copyright, because he’s attempting to supersede that work by importing his own ideas to it.” Not sure which blogpost is the focus of your interest here, but I commonly copy and criticize pertinent parts of publications in order to help spread the news and, whenever necessary, to show errors and omissions. In science this is the process for arguing a new hypothesis. Copyright laws are not violated when arguing scientific validity. Whether it’s ‘confirmation’ or ‘refutation’ this is all legal, standard and how could we ever do without it? All work is cited. Often links are made to the original sites.

5. “He will refuse any critical comments to be posted on his WordPress site.” Actually just the opposite. I rarely get feedback, but it’s all there to be viewed over the last 7 years. I do edit emotionally charged words (cussing) from reader replies and I edit out ad hominem attacks as they are inappropriate for a scientific discussion.

Moreover, I make changes all the time whenever new data comes in, because, like anybody, I make mistakes, too. Nearly every one of the 1284 included taxa was new to me when I first studied it. Any scientist would say the same thing.

Trevor, since the cladogram is the core of the study, I encourage you to look at the site and tell me which taxa should not nest together and where they should nest instead. I would hate to think that you simply listened to an opinion without checking out the facts.

Sometimes it takes an outsider to shed light on false paradigms. I have been published in Nature, Science, the Journal of Vertebrate Paleontology, Ichnos, Historical Biology and other peer-reviewed academic publications, so despite lacking a PhD, I have made contributions to the literature and continue to do so.

A large gamut analysis of the tetrapod family tree has been long sought by the paleo community. Now that it is available online, apparently that’s not what they really wanted all along.

Best regards, and let’s have lunch sometime.

David Peters
www.ReptileEvolution.com/reptile-tree.htm
www.PterosaurHeresies.Wordpress.com

 

What are birds-of-paradise? (part 2, Paradisaea minor)

 Figure 1. Paradisaea minor skeleton somewhat matched to in vivo pose.


Figure 1. Paradisaea minor skeleton somewhat matched to in vivo pose.

Yesterday a bird-of-paradise (BoP; Semioptera) was added to the large reptile tree (LRT, 1285 taxa) based on skull material only. It nested between the lyrebird and the roadrunner (genera: Menura and Geoccocyx, respectively) within the trumpeter/cuckoo clade. Crows (genus: Corvus) are the traditional (based on DNA) sister clade.

Fortunately,
I found a BoP skeleton online (Figs. 1, 2). It belongs to Paradisaea minor (Shaw 1809), the lesser bird-of-paradise. In BoPs the legs are shorter than in sister taxa, reflecting an instance of phylogenetic miniaturization at the genesis of the clade.

Even with the semi-crappy data currently available
(note the tibia and femur flipped upside down, lack of ribs and the lo-rez image overall) the LRT was able to successfully nest the BoPs together, apart from crows and jays.

Figure 2. Skull or Paradisaea minor, the lesser bird-of-paradise.

Figure 2. Skull or Paradisaea minor, the lesser bird-of-paradise.

Let’s not forget
that trumpeters and lyrebirds are both jungle residents, as are BoPs.

References
Shaw 1809. General Zoology 7 pt2:486

wiki/Lesser_bird-of-paradise