Subject: Bumblebee Mimic

From: Hank Brodkin <[email-masked]>
Date: Fri, 16 Jun 1995 20:12:04 -0700

On 6/13 on the north slope of Frazier Mountain in Ventura County,
California I was observing Spring Azures (Echo Blues) [Celastrina ladon]
and (Western) Brown Elfins [Callophrys augustinus] nectaring on a Golden
Current shrub along with many other insects including several large
bumblebees (Bombus sp.) when I saw what was later identified as a Bumble
Bee Moth (Hemaris diffinis).
Does anyone know the reason for this mimicry?  This sphinx/hummingbird
moth certainly is maneuverable enough to escape most predators - so it
seems hard to believe that it uses the bumble bee pattern for protection.
Anyone out there studying this beast?
For the record the elevation was between 6600 and 6800', the temperature
around 80F and the time around 12N.

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        Hank Brodkin <[email-masked]> Marina Del Rey, CA
                        33.58'24"N 118.27'39"W
 finger <[email-masked]> for information about the Calbird-L Mail List

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From: [email-masked] (Doug Yanega)
Date: 17 Jun 1995 21:03:28 GMT

In article <[email-masked]>,

> Anyone out there studying this beast?

It certainly *does* mimic a bumblebee for protection...there are two
Hemaris species, both good bumblebee mimics, and their color patterns
change geographically to match the locally-abundant bumblebees. *NO*
insect is uncatchable. Even Bot Flies are bee mimics, and they fly about
as fast as an insect can. After a few million generations of natural
selection, even a slight survival advantage can add up.
-- 
Doug Yanega
Illinois Natural History Survey, Center for Biodiversity
607 E. Peabody Dr. Champaign, IL 61820  USA
"There are some enterprises in which a careful disorderliness is
    the true method" - Herman Melville, Moby Dick

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From: [email-masked] (Julie K. Stahlhut)
Date: 18 Jun 1995 22:35:20 GMT

>seems hard to believe that it uses the bumble bee pattern for protection.

Well, having once in my childhood made the mistake of catching a speeding
bumblebee in my hand, I can see a distinct advantage to a non-stinging
insect which resembles a large bumblebee, even if it's a strong evasive
flier!  There are quite a few Batesian mimics of bees and wasps, including
syrphid flies, which are no slouches in the maneuverability department!

It would be interesting if someone has studied the responses of vertebrate
predators to bee-mimicking moths, though.  I'll be watching this space too!
-- 
Julie K. Stahlhut, Petite Mutant   [email-masked]
"Why ... yes ... I ... would ... like ... a ... knuckle ... sandwich."