Re: EARLY BIRD FROM SPAIN

[John Bois <jbois@umd5.umd.edu>]

On Thu, 1 Aug 1996, Nick Longrich wrote:

> I can't think of any reason to call bats clumsy fliers, and the fact
> that there are about 1000 species of them or something ridiculous
> like that proves that they're good enough at it to suit Mother
> Nature or natural selection.

But they are almost completely outcompeted in the day time by 
alula-bearing birds.  Any enhancement of aerial agility in a flying 
animal must have a telling selective edge.  Although this is 
self-evident, I also wonder whether other things such as increased 
heaviness due to having to carry offspring within, or fragility of bat's 
wings might also affect their day/night distribution?

 > Pterosaurs were very diverse, and they didn't have an alula.

...but seem to have become less diverse when things evolved that _did_ 
have alulas.