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Re: Euparkeria (Triassic archosaur) high bone growth rate



> Lucas J. Legendre, Loic Segalen & Jorge Cubo (2013)
> Evidence for high bone growth rate in Euparkeria obtained using a new
> paleohistological inference model for the humerus.
> Journal of Vertebrate Paleontology 33 (6): 1343-1350
> DOI: 10.1080/02724634.2013.780060
> http://www.tandfonline.com/doi/full/10.1080/02724634.2013.780060#.UoJNxPk_sbk
>
> We obtained an instantaneous
> growth rate of 6.12 μm/day, suggesting that Euparkeria shared with
> other non-archosaurian archosauromorphs (Prolacerta, Proterosuchus,
> and Erythrosuchus) a condition of high growth rate compatible with
> endothermy. [...] In conclusion,
> we provide new evidence for the hypothesis of an ancestral endothermic
> state for the last common ancestor of archosaurs, and show that
> non-archosaurian archosauromorphs and Triassic crurotarsans may have
> been characterized by a thermometabolism more similar to that of
> dinosaurs than to that of lepidosaurs and turtles.

...Wait a minute. *Prolacerta*, as its name says, is an entirely lizard-shaped 
animal. More precisely, with its long neck, it's highly reminiscent of a 
varanid. Now, the monitors do have elevated metabolic rates, as well as a cheat 
mechanism around Carrier's constraint, but endothermic or homeothermic they're 
not.

What are their growth rates like? What are their growth rates like under Early 
Triassic temperatures (very warm) and good food supply?