Fwd: Re: Sparring Bugs Question

Chip Taylor chip at ku.edu
Wed Oct 23 19:29:30 EDT 2002


>
>
>  In answer to Doug Dawn
>
>If I read your (and Chip's) messages between the lines, both of you 
>seem to suggest that because the smaller (male) butterfly is looking 
>for a mate he becomes more aggressive.  I am certainly with you 
>there.  Then both of you seem to make a small leap of faith in the 
>assumption that an aggresive male on the prowl can engender 
>fear--observed as a dramatic  fleeing flight-- in a much larger 
>butterfly. My question focused more on the "Why" that a large insect 
>would take the fear to heart instead of moving on ignoring the 
>little fellow and going merrily along.  The is a probably 
>hypothetical question as I doubt any observers of these scenarios 
>have ever seen a large bug indifferent.  But what could possible 
>happen if the little guy caught up to the big one - what damage 
>could be done.  Chip seemed to suggest that the large bug (Monarch 
>basically in the case) could not see behind him, such that an 
>approach from behind is a blind spot of danger, which is basically 
>saying it fools the big guy.

Sure, why not? This is simply avoidance behavior. If I were to throw 
a ping pong ball at your head when you weren't looking but which you 
could "see" with your peripheral vision, I'd bet you would duck. On 
the other hand, if you saw the ball coming and could recognize it as 
a non threat, you might not move or would attempt to catch the ball. 
Reasoning is not an option for insects and in the wild rapidly 
approaching objects, imperfectly perceived, are best avoided since 
they could mean death.

The most detailed studies of insect eyes suggest that the eyes have 
areas of special sensitivity associated with specific functions. 
Ommatidia in the eyes of the worker honey bee are sensitive to the 
planes of polarization in a manner that allows them to identify the 
position of the sun as they circle. Drones have specialized areas in 
the upper frontal portion of the eye the better to chase queens with. 
Similarly, the work by Ron Rutowski shows that perching butterflies 
(males of Asterocampa) have areas of sensitivity that allows them to 
detect and respond to potential mates and competitors.

Mere speculation but I would bet that the who wins question is a 
function of age, condition, interval of recent flight, energetics, 
and thoracic temperature.

>
Exactly what damage has been observed inflicted in any case of 
sparring butterflies, even two like males?  Why does one quit and the 
other prevail,
-- 
Monarch Watch
e:  monarch at ku.edu
w: http://www.MonarchWatch.org/
Dplex-L:  send message "info Dplex-L" to Listproc at ku.edu
p: 1 (888) TAGGING (toll-free!) -or- 1 (785) 864 4441
f: 1  (785) 864 5321
usps:  University of Kansas, Entomology Program, 1200 Sunnyside
Avenue, Lawrence, KS 66045-7534
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://mailman.yale.edu/mailman/private/leps-l/attachments/20021023/38e6d23e/attachment.html 


More information about the Leps-l mailing list