Donald A. Windsor Norwich, NY
Post #6
Hosts seem to be unable to repel
parasites at the species level. If they were able, they would be
parasite free, which they are not. In fact, some parasites have
coevolved with their hosts in a continual arms race to the point
where the hosts seem to be addicted to their parasites.
Why? Why is parasitism a property of
life? Why is it so widespread? What is it that parasites do to
maintain the susceptibility of their hosts? Why cannot hosts evolve
to repel the parasites that harm them?
Predation is a property of life, but it
is external to the prey, so the prey cannot do much about it. But
parasitism is based on easy entry, so hosts do have a chance to
thwart entry. Perhaps parasitism is a form of predation. But, even
if it is, it is different enough to warrant special study.
Perhaps parasites put "cookies"
on their hosts' genomes. Cookies are programming codes that one
computer puts on another computer to recognize it. Perhaps parasites
insert genetic, or epigenetic, material into their hosts' genome.
These parasite cookies would allow free passage into or onto their
hosts' bodies.
Other symbionts besides parasites might
also use cookies.
Sure, this is speculation on my part,
because I have no data to support it. However, I prefer to regard it
as a working hypothesis, one that can be tested by looking for
parasite cookies.
===========================================
No comments:
Post a Comment