Matt Jones wrote in message <7ake8t$ok7$1 at fremont.ohsu.edu>...
..................>So in that sense, they're not
>garbage, they're highly evolved, highly specialized systems for getting
>the most diversity in the range of neural responses. Maybe this is right.
>But maybe it was just evolutionarily cheaper to leave all these extra
>proteins lying around than it would be to get rid of them once they're
I am not sure if this of off-the-wall or even pertinent, but spiders (as
well as other venomous animals) frequently use numerous variations of the
same general type of toxin, e.g. sodium channel agonist, calcium channel or
potassium channel antagonist and etc. Some of this diversity may be due to
the diversity of prey which the venoms must handle, but the venoms may also
act synergistically ... getting a more reliable knock-down by hitting more
than one sub-type of receptor.
On the flip side, I am wondering if a greater diversity of channels and
receptors could offer some resistance to toxins (of any origin). For
example, if a nerve is using multiple sub-types of potassium channels it may
still continue to function if some of these is knocked out. Similarly,
alternate pathways (with different channels or receptors) might kick in if
another is affected. This might offer some adaptive advantage which may
mitigate against garbage collection.