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Re: Individual Age

Jonathan R. Wagner wrote:
> >and others still show signs of a Haversian Canal system, a marker for
> >Endothermy.
>         Recent experiments suggest that this is really a marker for high
> activity levels. I believe they ran some poor unfortunate lizard on a
> treadmill for a very long time and observed Haversian systems in its bones. :)

I've got to put in my own two cents worth here. This lizard was
subjected to constantly optimised temperatures and fed more than it
could ever possibly catch in the natural environment in order to
sustain these activity levels. In other words, the laboratory allowed
it to do what only an endotherm could do in the wild. So yes, the
haversion canals are a result of activity levels, but these are
activity levels that only an endotherm can sustain outside of a
laboratory! This is another one of those times that I'm astonished at
how outright stupid professional scientists can be sometimes. A lot of
time, effort and I'm sure money was put into an experiment that was
invalidated by its own methodology!