Tremex behaviour

[Barry M. OConnor]

At 11:12 AM +0200 9/5/02, Susanne Schulmeister wrote:

>If I understand you correctly, the mites do not feed from the mammals,
>but use them simply as a habitat. In that case, it is not such a big
>deal to switch the "host" (habitat). (I wouldn't even call that a host
>switch -- rather a habitat switch.)
>
>The case with the horntails is completely different. Even though the
>adult does not feed from the tree / horse, the larva certainly does
>(from the tree). And it is extremely unlikely that a larva adapted to
>feeding on wood would happily consume horse flesh. That would be hell
>of a host switch and it can only be a mistake, in my opinion.
>
The mite situation is interesting because the mites in the large mammal
ears are presumably feeding on materials of host origin (cerumen, tissue
fluid, or bacteria in such fluids).  Thus, in one sense they are parasites.
They are certainly specific to their particular host groups anyway.
        I can't believe that the Tremex-horse association is anything but
accidental.  But the mite case does at least provide some evidence that
"accidental" dispersal events leading to new habitats may lead to
establishment of new associations.
        All the best! - Barry

Barry M. OConnor
Curator & Professor             phone: (734) 763-4354
Museum of Zoology               FAX: (734) 763-4080
University of Michigan          e-mail: bmoc at umich.edu
1109 Geddes Ave.
Ann Arbor, MI 48109-1079  USA