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Re: Climate change



>Don't forget that a climate change would be much more likely to affect small,
>delicate animals than the big ones, like dinosaurs.

I disagree- A large animal needs a large food supply- and assuming a bolide
impact and darkening  of the sky, would have a lot of trouble finding it.

>If the global temperature drops 20 degrees, for example, who would
>survive, a 30-ton brachiosaurid or a 6-ounce salamander? The
>brachiosaurid can pick up and move hundreds of miles to the south
>(or north) to get to a warmer environment, but the little salamander
>has to stay there and freeze. As Bakker once said, "It's cheap to be
>big."

There is no evidence the dinosaurs ever migrated -north/south. Nor is there 
any evidence they had navigation skills, nor a weather sattelite to find
the warmer areas- There may not have been warmer areas. As
it seems likely a shroud of particulate matter would have  covered
the entire earth.  With the 
amount of particulate matter that a bollide would release-it is quite possible
that  their was no or little light for years.  Plants would die rapidly - The 
more food you need, the more likely you are to die in those circumstances.
This applies in the sea (where the base of the food chain in photoplankton)
just as much as on land.

Large carnivores would go first. (as in contemporaary droughts). Next go
large herbivores.   Warm blooded animals (mammals, birds) would be favoured 
because of their resistance to the cold, albeit at the expense of a larger
food requirement, so only small examples could survive.


>But if you look at the fossil record, wherever there is a mass
>dinosaur extinction there is virtually no corresponding sharp drop
>in the number of small animal species.


For the reasons mentioned above.

> With the information that I have now, my vote is for a global dino
> plague.

There is no evidence of this- And why did this plague affect only animals
25 kg or over-  A diverse range of species, including amphibians and 
fish and plants also perished was this just coincidence??
 
                Tony Mills
                Roehampton Institute London
                Tel (work) ++44 181-392-3121
                tonym@roehampton.ac.uk