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Quetzalcoatlus ecology (was T. rex vision)

Dr Naish concludes that, based on the anatomical evidence, "azhdarchids were stork-like generalists, picking up assorted invertebrate and vertebrate prey from shallow water and/or terrestrial environments." I like his line of reasoning, although I doubt it's the last word on the topic. I hope his blog on azhdarchid ecomorphology, by reference to modern analogs, gets morphed into a paper.

Like Jim, I also find the stork analog unlikely. I think Darren (despite being quite an insightful guy) has overlooked how storks actually feed; their feeding behavior actually has a lot of similarities to that of herons. In fact, storks sometimes snap up small birds that are airborne. Storks are rapid strike predators. Opportunistic yes, but not dippers.

It is also worth noting that Dr. Naish pins some of his conclusions on assumptions about Quetzalcoatlus flight parameters (and flight mechanics in general) that are in error. For example, he seems to confuse the adaptations for gliding and convective soaring. Vultures are great convective soarers; they're not great gliders. More to the point, Dr. Naish uses a broad-wing, low aspect ratio model of Quetz. planform to help reject the vulture-type hypothesis. This would, in fact, be evidence _for_ a vulture-like flight mode. I happen to disagree with that wing reconstruction for various reasons, and thus also reject the obligate scavenger model, so I agree on that point in the end. It is important to reject ideas for the right reasons, however.

There are also some errors concerning which locomotor modes have strong hindlimbs relative to the forelimbs, at least for the bird analogs. Note that length and robustness (or, more accurately, strength) should not be confused.

All that said, I love Dr. Naish's blog. Thanks to Darren for making such an informative and well-written blog available. I just happen to disagree with some of the points raised in this case.


--Mike H.