Competing for space on a fake walnut


Two male Rhagoletis walnut flies joust on an artificial walnut in a lab cage at the University of Arizona. What's an artificial walnut? It's a painted ping pong ball. As long as the ball is the right color and shape, the flies apparently don't mind.


Biologist Jeremy Davis uses these flies to study the interaction between fruit quality and fly behavioral ecology.


Of course, for the flies it's all about access to females.

Technical details.

top photo: Lens: Canon MP-E 65mm 1-5x macro lens
Body: Canon EOS 20D dSLR
Flash: Canon 550EX flash, indirect
Settings: ISO 200, f/11, 1/200 sec

middle photo: Lens: Tamron 11-18 wide angle zoom
Body: Canon EOS 20D dSLR
Flash: Canon 550EX flash, held overhead
Settings: ISO 100, f/8, 1/250 sec

bottom photo: Lens: Canon MP-E 65mm 1-5x macro lens
Body: Canon EOS 20D dSLR
Flash: Canon 550EX flash, handheld behind leaf
Settings: ISO 200, f/11, 1/200 sec

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Ah, the Ron Prokopy kind of research. I was fortunate to see him speak shortly before he died. One of the people I greatly admire - showed how much one can discover through creative experiments that do not even use electricity, let alone computers or other expensive machines. Decades of painting balls, cutting flowers, etc, taught us an awful lot about Rhagoletis flies in particular, and about insect behavioral ecology in general. He was one of the greats!

Rhagoletis pomonella is my second-favorite host-switching insect (after Leptinotarsa decemlineata)!

Gorgeous, gorgeous, gorgeous photos! I am so happy that this blog was added to the horde. :)

By ctenotrish (not verified) on 08 May 2009 #permalink

I love it. They look like they're high-fiving.

"Dude! Check out this awesome walnut we just scored! It's off the hizzaay!"

"Dude! Let's throw a kegger!"


I have a general existential question about your photography. You've mentioned that on some traveling trips, you set up a white box in your room and bring specimens back. What happens to those specimens after your photos? Are they already samples you're bringing home? Do you return them to where you found them, shove them out the window, just kill them, or eat them with fava beans?


Normally they're pickled and sent to whichever institution is relevant for vouchers (if the material is rare or otherwise noteworthy), or they end up in my own reference collection or released back out to where they came from (the dirt-common insects). Depends a lot on what it is.