ants
awild | February 16, 2009
Myrmecologist extraordinaire Mike Kaspari sends out the following call to arms:
I am working on a project with Jamie Gillooly examing how various life history traits scale in ant colonies. Specifically, we are testing the hypothesis that when total colony mass is used (instead of the mass of an individual in the colony) social insects scale much like their unitary counterparts.
From the subject heading, you can see where I am going with this. Allometries need to be tested across the entire natural range of variability, and a regression of total worker mass against queen mass (of monogyne…
awild | February 15, 2009Lasius (Acanthomyops) arizonicus with mealybug, Huachuca Mountains, Arizona.
Students of the North American myrmecofauna will undoubtedly recognize this ant. Pudgy, pleasingly orange in color, and smelling sweetly of citrus, the Citronella ant is an endearing creature.  This Nearctic endemic is among our most common ants, living in underground empires farming root aphids and mealybugs for sustenance.
Yet few people ever encounter these shy insects. They emerge above ground for only a few hours each year, in late summer to see off the colony's winged reproductives.
The dozen or so…
awild | February 14, 2009Who is supposed to read The Superorganism?
I can't really tell. While I'm enjoying Holldobler & Wilson's latest tome, I am perplexed at the book's target audience. The text switches between broadly anthropomorphic prose clearly aimed for a general audience and obtuse jargon digestible only by the experienced biologist.
I get the feeling that the authors- at least one of them, anyway- desired a technical book more along the lines of Bourke & Franks, while the marketing department at Harvard University Press wished to trade on the authors' name recognition with a glossy coffee-table…
awild | February 12, 2009In honor of the old man's 200th, Myrmecos Blog is proud to feature Charles Darwin writing prophetically about the problems posed by social insects for his theory of natural selection.  The passage below is from the first edition of On the Origin of Species, and in it Darwin anticipates the same answers- kin and group selection- that later generations of biologists converged on to solve the riddle. Not bad for a barnacle taxonomist...
No doubt many instincts of very difficult explanation could be opposed to the theory of natural selection,âcases, in which we cannot see how an instinct could…
awild | February 11, 2009A few years ago I needed to image some ants for a short taxonomic paper. Lacking a decent specimen imaging system (like Entovision), I decided to snap the photos at home using my standard macro gear: a dSLR with the Canon MP-E lens. The images turned out fine and were published in Zootaxa with the paper.
Later, the Antweb team imaged the same species using their standard set-up: a high-res video camera on a Leica microscope, focus-stacking the images with specialized software. I decided to compare the two. Here they are (click on each to view the uncompressed file):
Pachycondyla…
awild | February 10, 2009 There's been a debate simmering among Argentine Ant researchers about the difference between the ant's ecology in its native South America and in the introduced populations. The heart of the disagreement is this: is the introduced Argentine ant dominant because its biology changed during introduction, or because the ecologies of the native and introduced ranges are different?
Like most scientific debates, some aspects are factual in nature while others are semantic. Sometimes the semantic and the factual become confused in a way that makes it difficult to tease the arguments apart…
awild | February 9, 2009Simopelta sp. nr. pergandei, Venezuela
I've just started a project in collaboration with Daniel Kronauer, Jack Longino, and Andy Suarez to infer the phylogeny of species in the Neotropical ponerine genus Simopelta. If you happen to have any DNA-quality specimens of these unusual ants in your keep, we'd greatly appreciate a donation.
Why Simopelta? These insects are among the "other" army ants, the barely-known lineages that have also evolved the specialized nomadic lifestyle that characterizes the well-known, photogenic, and oft-televised ecitonine and doryline army ants. Yet Simopelta…
awild | February 9, 2009Reader Sam Tomkinson has been experimenting with my tracing-paper diffusion trick and took this lovely shot of a Myrmecia bull ant in western Australia:
Myrmecia are aggressive ants with a nasty sting, so kudos to Sam for putting his life at risk to bring us a taste of wild Australia.
It also occurs to me to explain that Aussies call the larger Myrmecia species "Bull Ants", and "Red" is used as a modifier. They aren't predators of energy drinks. Although if they were, those teeth could probably open a can.
awild | February 8, 2009
In the comments, blogger Huckleberry Days asks:
Speaking of tasty, what about chocolate covered ants: which ants are used?
Having never made chocolate-covered ants, I am not the best person to be opining about formicine confections.  I do, however, have many years' worth of mostly accidental ant ingestion experience, enough to offer the following advice for choosing a species to coat in chocolate. Here's what to look for:
Medium-large species at least 6-10 mm in length. Smaller ants won't give your candy any noticeable crunch.
Species with a strongly acidic chemistry will yield an…
awild | February 7, 2009
Formica francoeuri tending larvae of the copper butterfly, Lycaena xanthoides. Southern California
photo details: Canon MP-E 65mm 1-5x macro lens on a Canon EOS 20D
ISO 100, 1/250 sec, f/13, flash diffused through tracing paper
awild | February 6, 2009As if butterflies weren't flamboyant enough already, it seems that some of them actively impersonate queens.
Queen ants, that is. A report by Francesca Barbero et al in today's issue of Science documents a clever strategy employed by a European butterfly, the Mountain Alcon Blue Maculinea rebeli, to infiltrate nests of Myrmica schencki. The immature stages of the butterfly are parasites of ant colonies, and it seems the secret to their success is acoustic mimicry. The larvae and pupae squeak like queens, eliciting preferential treatment from the workers. Here's the abstract:
Ants…
edyong | February 6, 2009Ants are among the most successful of living things. Their nests are well-defended fortresses, coordinated through complex communication systems involving touch and chemical signals. These strongholds are stocked with food and secure from the outside world, so they make a tempting prospect for any burglars that manage to break in.
One species of butterfly - the mountain alcon blue (Maculinea rebeli) - is just one such master felon. Somehow, it manipulates the workers into carrying it inside the nest, feeding it and caring for it. The caterpillar does so little for itself that it packs on 98…
awild | February 5, 2009A trail of Atta leafcutting ants in Gamboa, Panama.
From the recent literature:
The Journal of Experimental Biology has a lab study by Dussutour et al documenting how leafcutter ants avoid traffic jams under crowded trail conditions. Apparently, unladen ants increase a narrow trail's efficiency by following the leaf-carrying ants instead of trying to pass their slower sisters. See also commentary by JEB and Wired.
source: Dussutour, A., Beshers, S., Deneubourg, J. L., Fourcassie, V. 2009. Priority rules govern the organization of traffic on foraging trails under crowding conditions in the…
awild | February 4, 2009The blue-green iridescence on these Iridomyrmex purpureus workers shines from microscopic sculpturing on the ants' cuticle.
I've never taken to the Australian vernacular for one of their most conspicuous insects. The latin Iridomyrmex purpureus translates as "purple rainbow ant", referring both to the base color of the body and to the attractive metallic refractions on the cuticle. But Aussies instead call this colorful species the "meat ant." Crass by comparison.
On the other hand, it'd probably not do my reputation of masculine bravado much good were I to stroll into a dusty pub in the…
awild | January 31, 2009
My earlier list of the most-studied ant species contained a few omissions. Here is a more inclusive list:
Ant species sorted by number of BIOSIS-listed publications, 1984-2008
The Top 10 Species
Publications
Solenopsis invicta
984
Linepithema humile
343
Lasius niger
250
Formica rufa
167
Atta sexdens
163
Formica polyctena
160
Solenopsis geminata
151
Myrmica rubra
142
Monomorium pharaonis
121
Atta cephalotes
112
The Rest
Publications
Oecophylla smaragdina
111
Solenopsis richteri
110
Pheidole megacephala
104
Tetramorium "caespitum"
93
Formica fusca
92
Myrmica ruginodis
88
Pogonomyrmex…
awild | January 29, 2009Pheidole moerens, major worker, Louisiana
Pheidole moerens is a small, barely noticeable insect that travels about with human commerce, arriving without announcement and slipping quietly into the leaf litter and potted plants about town.  As introduced ants go, P. moerens is timid and innocuous- it's certainly no fire ant. The species is now present in the southeastern United States, a few places along the west coast, and Hawaii. Conventional wisdom suggests that P. moerens originated in the Greater Antilles, but even though the ant was first described from Puerto Rico a century ago…
awild | January 27, 2009Widow spider and harvester ants. Hallelujah Junction, California
This young black widow (Latrodectus hesperus) set up shop above the nest entrance of a colony of Pogonomyrmex harvester ants. It's an all-you-can-eat buffet, allowing the spider nearly unlimited pickings as the ants come and go.
The spider's mottled coloration is typical of young widows; they don't acquire the striking black and red warning garb until maturity.
photo details: Canon 100mm f2.8 macro lens on a Canon EOS D60
ISO 100, 1/200 sec, f/11, MT-24EX twin flash
awild | January 26, 2009Owing to a volume of incoming specimen requests, I've added a tab in the top menu for Myrmecology News to hold items like specimen requests and miscellaneous ant-related announcements so they don't scroll off the bottom of the blog too quickly.
If you've got something to post, please email me, alexwild -at- illinois.edu (but replace the "-at-" with @, of course).
awild | January 26, 2009Ted Schultz writes:
Postdoc Scott Solomon has arrived here at the Smithsonian to work on the systematics and phylogenetics of Trachymyrmex and Acromyrmex ants and fungi. Scott has spent a fair amount of time collecting in South America, but we want to be sure that we have an exhaustive representation of species as well as multiple examples of species from across their ranges. Â To that end, we're contacting folks to inquire about whether they might have Trachymyrmex or Acromyrmex specimens that we can use in this project, particularly from undercollected localities.
Ideally, we require…
awild | January 26, 2009
Rachelle Adams writes:
I have begun a one year postdoc molecular project focusing on the species in the Solenopsidini tribe with Ted Schultz and Seán Brady at the Smithsonian, Washington DC. Due to the vastness of this tribe and its taxonomic challenges, I want to thoroughly sample each genus currently classified in the tribe as well as those that were historically classified as solenopsidines. ANY samples that belong in the genera listed below are needed. I have also included a species âwish listâ that will complement a morphological study done by Juanita Rodriguez and my dissertation…