Effigia okeeffeae, a shuvosaurid (an historic relative of the crocodiles) that lived in North America through the Triassic interval, was a specialist herbivore that possible ate up delicate plant materials, in response to new analysis led by the College of Birmingham.
Life reconstruction of Effigia okeeffeae. Picture credit score: Mark Witton.
Effigia okeeffeae was concerning the measurement of a gazelle and lived in North America round 205 million years in the past.
Its fossil stays had been discovered within the Ghost Ranch Quarry in New Mexico within the Forties, though the fabric was not formally described by paleontologists till 2006.
The stays had been comparatively poorly preserved within the quarry and the cranium, specifically, was fairly badly deformed, making correct reconstruction problematic.
Early evaluation of the specimen concluded that it belonged to the group of reptiles that features crocodylians and birds and which began to flourish within the Triassic interval.
Though extra carefully associated to crocodylians, Effigia okeeffeae’s light-weight physique, elongated neck, giant eyes and beak shared many similarities with a modern-day ostrich, main paleontologists to imagine the animal fed by pecking plant materials from the bottom.
However the brand new evaluation revealed the Triassic animal was in all probability a completely totally different kind of herbivore than beforehand thought.
“Effigia okeeffeae reveals an ‘ostrich-like’ bauplan comprising a gracile skeleton with edentulous jaws and enormous orbits, just like ornithomimid dinosaurs and extant palaeognaths,” mentioned lead writer Dr. Jordan Bestwick from the College of Geography, Earth and Environmental Sciences on the College of Birmingham and colleagues.
“This bauplan is thought to be an adaptation for herbivory, however this speculation assumes morphological convergence confers purposeful convergence, and has acquired little specific testing.”
Within the examine, the authors used new CT scans of Effigia okeeffeae’s cranium which revealed a way more correct reconstruction of the animal.
This included new details about the form of the cranium, equivalent to a extra rounded, bulbous mind cavity and curved higher and decrease jaws.
Not like an ostrich invoice, which is extra rounded, Effigia okeeffeae’s invoice is extra concave with jaws that open and shut a bit like a pair of shears.
The researchers used this info to mannequin the consequences of various forces appearing on the cranium, together with what occurs when the animal pecks on the floor.
By modeling the forces the cranium would want to resist with a view to feed by pecking, the scientists calculated that Effigia okeeffeae’s cranium would in all probability have shattered.
As an alternative, they counsel, the animal could be extra possible to make use of its jaws to snip off and nibble items of sentimental plant materials equivalent to younger shoots, or ferns.
“The herbivores we already acknowledge within the Triassic interval fed both by digging for roots, such because the pig-like aetosaurs, or reaching for leaves excessive up within the treetops, just like the long-necked sauropods,” Dr. Bestwick mentioned.
“These two-legged browsers with a weak chunk are distinctive to this era and present a beforehand unrecognized variety among the many herbivores of this era.”
The group’s outcomes had been revealed in The Anatomical File.
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Jordan Bestwick et al. Cranial purposeful morphology of the pseudosuchian Effigia and implications for its ecological position within the Triassic. The Anatomical File, revealed on-line November 29, 2021; doi: 10.1002/ar.24827