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Re: four winged Archaeopteryx


This brought something to mind:

"the long bony tail provides a huge amount of drag rather than lift"

It appears that both pterosaurs and birds had long tails in the  ancestral
form and with tailess designs being the only ones to avoid extinction when
crisis came.

Has anyone looked into the problem of stability in tailess forms and overall
effect on drag? It should be possible to calculate generalised tradeoffs over a fair range of flight envelope (at least low and high speed, moment).

It might even be possible to do a follow up study on modern birds that have
long tail feathers (eg. the Pica pica I saw at Tyrell a few years back). It
would be interesting to see if they have any role in flight or are only
ordamental (and if this correlates with niche or flight abilities).

In particular the results could possibly have interesting implications for
evolutionary rates and neural development.

It is too bad that the fossil record is so fragmentary as it would be
fascinating if tailess forms appeared during a radiation into a new set of
niches and co-existed with the long tailed forms for a fair period of time
(especially if secondary characteristics changed at the same time).

By the way, what do people think of the idea that birds outcompeted
terrestrial forms for the smallest predatory niches in the late Cretaceous?

-Jonas Weselake-George