The Case of the Scimitarian Mandibles. Here is a male Lasioglossum acuminatum (from Wisconsin, thanks Nolan Amon!). L. a. is part of the Big Lasioglossum group. They are all black (no metallic glitterings here) much bigger than than the other groups. For technical reasons they are called the Lasioglossum sensu strictu subgenus, which someone else will explain to you as to why it is Lasioglossum in the "strict sense", but not me. Now, look at those long mandibles. A not uncommon length for L. sensu strictu group males. The females have the usual "I have to do all the work digging the kids home" mandibles that most sensible females in the bee world have, but, really, what use are those long mandibles for you males? They certainly don't dig, in fact they are really just sex machines donating their sperm to progenitzise themselves into future generations. Do they fight with them?...seems both unwieldy and unlikely since I think the females don't have time to watch Lasioglossum gladiator rounds. Perhaps it is a "look at me" sort of thing, where large mandibles (maybe all oiled up?) increase mating opportunities. Interestingly, pattern is absent in most of the other Lasioglossum groups, the males mostly have tiny wittle mandibles, smaller than the females (very reasonable since they don't have to go around digging with them). The exception being a few males in the Hemihalictus subgenus. Why? Why? Why? I have no answer, but are listening to your theories. ~~~~~~~~~~{{{{{{0}}}}}}~~~~~~~~~~
All photographs are public domain, feel free to download and use as you wish.
Photography Information:
Canon Mark II 5D, Zerene Stacker, Stackshot Sled, 65mm Canon MP-E 1-5X macro lens, Twin Macro Flash in Styrofoam Cooler, F5.0, ISO 100, Shutter Speed 200
We Are Made One with What We Touch and See
We are resolved into the supreme air,
We are made one with what we touch and see,
With our heart's blood each crimson sun is fair,
With our young lives each spring impassioned tree
Flames into green, the wildest beasts that range
The moor our kinsmen are, all life is one, and all is change.
- Oscar Wilde
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Want some Useful Links to the Techniques We Use? Well now here you go Citizen:
Best over all technical resource for photo stacking:
www.extreme-macro.co.uk/
Art Photo Book: Bees: An Up-Close Look at Pollinators Around the World:
www.amazon.com/Bees-Up-Close-Pollinators-Around-World/dp/...
Free Field Guide to Bee Genera of Maryland:
bio2.elmira.edu/fieldbio/beesofmarylandbookversion1.pdf
Basic USGSBIML set up:
www.youtube.com/watch?v=S-_yvIsucOY
USGSBIML Photoshopping Technique: Note that we now have added using the burn tool at 50% opacity set to shadows to clean up the halos that bleed into the black background from "hot" color sections of the picture.
www.youtube.com/watch?v=Bdmx_8zqvN4
Bees of Maryland Organized by Taxa with information on each Genus
www.flickr.com/photos/usgsbiml/collections
PDF of Basic USGSBIML Photography Set Up:
Google Hangout Demonstration of Techniques:
plus.google.com/events/c5569losvskrv2nu606ltof8odo
or
www.youtube.com/watch?v=4c15neFttoU
Excellent Technical Form on Stacking:
www.photomacrography.net/
Contact information:
Sam Droege
sdroege@usgs.gov
301 497 5840