svp abstracts of interest or bombast 2024: K–N

It is abstract season.
Here are selected sentences from selected abstracts from SVP 2024 – Minneapolis:

Figure 1. Tetraceratops and relatives: Concordia and Reiszorhinus in the LRT. ” data-image-caption=”

Figure 1. Tetraceratops and relatives: Concordia and Reiszorhinus in the LRT.

” data-medium-file=”https://pterosaurheresies.wordpress.com/wp-content/uploads/2024/11/tetraceratops_spindler588.jpg?w=149″ data-large-file=”https://pterosaurheresies.wordpress.com/wp-content/uploads/2024/11/tetraceratops_spindler588.jpg?w=509″ class=”size-full wp-image-89569″ src=”https://pterosaurheresies.wordpress.com/wp-content/uploads/2024/11/tetraceratops_spindler588.jpg” alt=”Figure 1. Tetraceratops and relatives: Concordia and Reiszorhinus in the LRT.” width=”584″ height=”1176″ />

Figure 1. Tetraceratops and relatives: Concordia and Reiszorhinus in the LRT. Note the rising jaw tips and splitting nares. Also note the raggedy edges of the squamosal (magenta).

Mercado MM et al: A Micro-CT based reconstruction of Tetraceratops insignis (Synapsida;Eupelycosauria) and new insights into its taxonomy and biology.
“Tetraceratops insignis is an enigmatic early Permian synapsid, known from a single skull.”

In the LRT Tetraceratops (Fig 1) is not a synapsid, but close to Resizorhinus and Concordia sharing a longer list of traits than any synapsid.

“This damage has prevented decisive interpretation of its anatomy, obscuring the phylogenetic affinity of Tetraceratops and its putative therapsid identity.” “μCT scanning of the specimen has provided new details of its anatomy.”

Taxon exclusion is the problem here, not ‘new details of its anatomy.”

Figure 2. Thanatosdrakon compared to Quetzalcoatlus showing the distinct morphologies. ” data-image-caption=”

Figure 2. Thanatosdrakon compared to Quetzalcoatlus showing the distinct morphologies.

” data-medium-file=”https://pterosaurheresies.wordpress.com/wp-content/uploads/2022/04/thanatosdrakon_quetz_recon2-588.gif?w=193″ data-large-file=”https://pterosaurheresies.wordpress.com/wp-content/uploads/2022/04/thanatosdrakon_quetz_recon2-588.gif?w=584″ class=”size-full wp-image-66921″ src=”https://pterosaurheresies.wordpress.com/wp-content/uploads/2022/04/thanatosdrakon_quetz_recon2-588.gif” alt=”Figure 2. Thanatosdrakon compared to Quetzalcoatlus showing the distinct morphologies.” width=”584″ height=”908″ />

Figure 2. Volant Thanatosdrakon compared to flightless Quetzalcoatlus showing the distinct morphologies.

Miller K et al: Terror from the skies? Investigating the energetics and feeding ecology of the largest pterosaurs Quetzalcoatlus.
“Pterosaurs, a lineage of Mesozoic flying archosaurs, include the largest flying animals
ever known.”

The largest azhdarchids were flightless and became extra large because they were flightless, as in the largest birds. The largest flying pterosaurs were pteranodontids and ornithocheirids where no wing elements were reduced.

“Despite the great wingspan of Quetzalcoatlus,

Actually Q had a relatively small wing, actually, with vestigial distal elements (Fig 2).

“Given these factors (expected glide speeds on the order of 20 m/s or more, the costs of landing and launching are high, the maximum gut capacity low) we suggest that the primary ecological role was a terrestrial walking small prey specialist and/or scavenger.”

Finally! Someone agrees that flight was not the prime manner of locomotion.

“we suggest it played the role of a lower trophic level consumer andnot an apex predator”

Miller K and Beard KC: Re-assessment of the relationships within the plesiadapiform family Microsyopidae in North America.
“Plesiadapiforms (Mammalia, Primatomorpha) are an extinct, paraphyletic group that figure
prominently in discussions of primate origins.”

Not confirmed in the LRT, where Plesiadapis and Microsyops are close to the aye-aye, Daubentonia, rodents and multituberculates. Primates nest elsewhere.

Napoli JG et al: Reorganization of the theropod wrist facilitated the origin of avian flight.
“The plesiomorphic condition for theropod dinosaurs is to have six discrete carpals, but only four persist in modern birds, and the homologies of these carpals have been historically contentious. The posterior-proximal carpal has proven especially problematic – while often identified as “ulnare”, recent embryological studies demonstrate that this element is actually the pisiform. The pisiform is primitively a small, peripheral sesamoid, but
in birds it migrates into the main carpal block, impeding development of the ulnare before
replacing it both topologically and functionally.”

Good to know!

“The apparent absence of a pisiform in all nonavian theropods has led to proposals that it
was lost as an ossified element early in theropod evolution, and secondarily regained
only within Avialae.”

So… the authors just painted themselves into a corner.

“We report two new exceptionally preserved theropods from the Gobi Desert of Mongolia that preserve articulated carpi, and clearly demonstrate the presence of a pisiform within the broader clade Pennaraptora. The first of these is a new specimen of Citipati. The second is a new species of troodontid, which also preserves an articulated carpus and has a small pisiform in the posterior-proximal position.”

In the LRT oviraptorids, ornithomimids and tyrannosaurs are compsognathids.
Troodontids are much closer to birds.