Re: Extinction due to "blue balls"

[Waylon Rowley <cryptovolans@yahoo.com>]

Garrison Hilliard wrote:

> An asteroid may have wiped
> out the dinosaurs 65 million
> years ago not simply by changing the world's climate
> and causing years of dark
> skies, but also by causing too many of them to be
> born male. 
 
This reminds me of the idea that mammals gobbled up
all the dinosaur eggs, leading to their eventual
extinction. It seems a bit of a stretch.
 
> But in crocodilians, turtles and some fish, the
> temperature at which eggs are
> incubated can affect the sex of the developing
> babies... 
> ..."These animals live at the intersection of
aquatic
> and terrestrial environments,
> in estuarine waters and river beds, which might have
> afforded some protection
> against the more extreme effects of environmental
> change, hence giving them more
> time to adapt," the researchers wrote. 

1) if air temperature drops, there's going to be a
proportional drop in ground temperature, where crocs
and turtles bury their eggs, save alligators, which
build vegetation mounds.

2) IIRC, Horner claims that hadrosaurs covered their
nests in plant material as well. The nesting oviraptor
specimen should have been producing _some_ heat for
its clutch, assuming it was endothermic and retained
the feathers found on its kin.

3) dinosaur remains are found in areas believed to be
somewhat cold, such as alaska, antarctica, and
"dinosaur cove" in australia. Maybe they didn't breed
and lay eggs there, and migrated to a more suitable
location, but let's not try to force-fit an idea.

4) who knows how many generations of offspring a small
dinosaur could produce relative to its croc/turtle
counterparts? that would be a major factor in
determining whether evolution had enough time to save
them from climate change.

that is all.

-Waylon R. 


        
                
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