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Re: Tilted world & more genetics



> 
> James Shields wrote;
> >Is it possible that the Earth's tilt has varied in the last few billion
> years? My guess is that it is.<
> 
> Could something like this account for magnetic flip-flops?

Simply - no.

The earths magnetic field is generated from within.  If the earth 
were to flip through 180 degrees would still be in the same 
orientation with respect to an observer (or suitable piece of rock 
in a plastic state) on the earth.

> Could species numbers have dropped below the healthy genetic breeding point
> at the K/T "event"? 

It certainly looks like they did.  After all, extinction pretty
much guarantees that.

Even if they did though, would it make a difference?  There is 
some genetic evidence that Cheetahs dropped down to perhaps as few
as two pairs at some point around the end of the last ice age.

They are apparently prone to genetic defects and this is affecting 
their ability to sustain their numbers where they are living in 
favourable areas.  However in the absence of competition (which 
may well be the case if a large number of animals were killed by 
an extraterrestrial object) it is unclear what effect that would 
have on the viability of the group.  After all, a higher number 
of mutations might mean a higher rate of speciation, which may
not be such a bad thing after a major die off.