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Showing posts from August, 2017

Spinosaurus, the gigantic pangolin of the Cretaceous?

I was made aware of this not long ago - it kind of looks creepy, but it gave me an idea:

Did Spinosaurus walk like a pangolin?

That is, with it's hands low to the ground but not touching the ground - so no knuckle walking - and maintaining balance as a biped...

This pangolin seems to maintain balance on its hind legs even though, on cursory glance, its centre of mass seems too far forward for that.

Spinosaurus is supposed to have had a dense femur, so maybe its centre of gravity was farther back than you'd think from overall proportions. Maybe the sail helped tip the scale back?

...or maybe it was a giant ant-eater? Those giant claws look particularly suited to breaking open termite mounds?

Who knows. This is me being silly, but thought it was hilarious enough to share...

Cope's Rule and rates of body size evolution

The evolution of body size has been the focus of countless studies, not only in palaeontology but also in evolutionary biology using data from extant animals (or neontology as palaeontologists would say). While some colleagues have argued recently that body size is not necessarily a good trait to study, nonetheless, it still stands that body size is an important factor of fundamental biological phenomena, including metabolism, physiology, biomechanics, and ecology. For instance, the largest source of variance in biomechanical performance measures like bite force is body size - a lion's bite force is an order or two higher in magnitude than that of a domestic cat just purely out of simple scaling. Similarly, prey size categories, such as large, medium/mixed and small, are highly affected by predator body size - obviously a tabby cannot kill an ox while a lion or a tiger can. Thus, body size is not only an important biological trait, but necessarily a fundamental physical trait.

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