Myrmecology
awild | May 28, 2009Aptinoma antongil Fisher 2009
Brian Fisher has a paper out in Zootaxa this week describing a pair of new ant genera from Madagascar. Aptinoma and Ravavy are small ants in the subfamily dolichoderinae related to Tapinoma and Technomyrmex. Apparently, the backstory on these new ants is that ongoing genetic research from the Ant Tree of Life project revealed some Malagasy specimens to be rather distantly related to any of the previously described genera. On closer morphological inspection, Fisher found several differences that allow for the new genera to be reliably diagnosed.
Yet another…
awild | May 28, 2009
A queen and worker Argentine ant, Linepithema humile, pose for a photograph near Córdoba, Argentina.
photo details: Canon MP-E 65mm 1-5x macro lens on a Canon EOS 20D
ISO 100, 1/250 sec, f13, flash diffused through tracing paper
awild | May 11, 2009
A bold paper by Rob Dunn et al in Ecology Letters is making news this month.  Dunn and an impressive list of coauthors pool observations of ant species richness from more than 1000 sites worldwide, finding that southern hemisphere habitats consistently support more species than their equivalents in the northern hemisphere. The pattern appears to be predicted primarily, but not entirely, by climate.
These results strike me as intuitively correct, and I suspect anyone who has collected ants in both hemispheres will agree. Brazil's fauna is spectacularly rich. That of Oklahoma, less so…
awild | May 5, 2009
Benoit Guenard has been hard at work the past couple years compiling broad-scale distribution data for all the world's ants, and his efforts are now online. Here they are- global range maps for all the ant genera:
http://www.antmacroecology.org/ant_genera/index.html
These maps will be a very useful resource, especially if the myrmecological community participates to add new records and vet the occasional error.
One thought, though, is that large umbrella strategies such as this will eventually be redundant with antweb.org. Â Antweb's distributions are built from accumulated individual…
awild | April 14, 2009It is due in large part to Rettenmeyer's tireless tracking of army ants through all manner of tangled tropical jungle, for months on end, that we know as much as we do about those creatures. We've lost a real giant of myrmecology.
awild | April 11, 2009Amyrmex: Dolichoderinae? Leptanilloidinae? Who knew?
A paper out this week in Zootaxa reminds us of the hazards of excessive reliance on the worker caste for ant taxonomy. Phil Ward and Seán Brady sequenced DNA from few genes from the enigmatic Amyrmex, a rarely-collected dolichoderine genus known only from males in South America. Except, it wasn't a dolichoderine. Surprise! Genetically, this little guy is part of the doryline section (the army ants and relatives) in the Leptanilloidinae.
Where did we go wrong with Amyrmex? In my opinion, it's in our dysfunctional dependence on…
sb admin | April 10, 2009
A screen capture in Google Earth reveals a pattern of pasture freckles in Entre Rios, Argentina.
How about a closer look? I drove past the site last week, and the landscape at ground level sports an array of domed mounds, each about half a meter in height:
And the little engineer behind the mounds?
Camponotus termitarius, the tacurú ant. This perky Argentinian native (often misidentified as C. punctulatus) frequently invades land degraded by agriculture and is an excellent example of how human land-use changes can convert an innocuous local species into a pest. In this case, the…
awild | April 2, 2009Kalathomyrmex emeryi (Forel 1907), Argentina.
In Zootaxa last week, Christiana Klingenberg and Beto Brandão introduced to the world an entirely new genus of fungus-growing ant, Kalathomyrmex. Yet the single species, K. emeryi, is a widespread neotropical insect that has been known for over a century. In fact, I photographed it twice during my recent trip to Argentina. How does this happen, a new genus devoid of novel species?
The answer is understandable in light of the distinct pattern of evolution among the fungus growing ants, revealed in a 2008 study by Ted Schultz and Sean Brady…
awild | February 28, 2009Those of you who were into ants in the early '90s might remember SimAnt, a simulation game where you control the decisions your ants make to steer a colony to dominance over a competing species in a suburban lawn.
The game is based, in part, on the optimality equations summarized in Oster & Wilson's 1978 text "Caste and Ecology in the Social Insects". The book lays out mathematical foundations for determining the investments a colony should place in workers, queens, and males in order to optimize Darwinian fitness over a range of ecological conditions. If you knew the equations,…
awild | February 23, 2009What's new in ant science this week? Lots.
Atopomyrmex mocquerysi, South Africa
Myrmecological News has posted a pair of studies online. The first, by Martin Kenne et al, observe the natural history of one of Africa's most conspicuous yet chronically understudied arboreal ants, Atopomyrmex mocquerysi. The second, by Jim Wetterer, is part of a continuing series on the global spread of pest ants. This installment targets Monomorium destructor.
Onychomyrmex sp., Australia
The Australian Journal of Entomology counters with a pair of its own ant studies. In the first, Hiroki Miyata et al…
awild | February 23, 2009Stenamma sp., California.
This request comes from Michael Branstetter:
I am working on a broad-scale phylogeny of the ant genus Stenamma and am in search of fresh specimens from the Old World. Stenamma is a cryptic genus that is most often collected in forest leaf litter. The genus is primarily Holarctic in distribution, but also has representatives in the New World tropics. Producing a phylogeny of the genus will help me in my quest to better understand the genus as a whole and to revise the Mesoamerican species. In the Old World there are species records from Europe, northern…
awild | February 23, 2009From my inbox, a postdoctoral job announcement:
The Department of Botany, La Trobe University, Melbourne, Australia seeks to appoint a Postdoctoral Fellow to conduct research in Invasion Biology on Christmas Island. Over the last decade, supercolonies of the invasive yellow crazy ant Anoplolepis gracilipes have spread across island rainforest and caused a variety of significant impacts. High ant densities are consistently associated with high densities of exotic honeydew-secreting scale insects. This project will determine the dependence of ant supercolonies on associated scale insects…
awild | February 21, 2009The port at Mobile, Alabama, photographed from across the bay.
The port city of Mobile, Alabama holds special significance for students of ant science. Jo-anne and I took a weekend trip down to the gulf coast in January, and as we are both myrmecologists we felt compelled to stop and take a few photographs. Not only is Mobile the childhood home of ant guru E. O. Wilson, but the city's docks have been the point of introduction into North America for some notorious pest ants. We'd have neglected our intellectual heritage to just drive through.
Mobile's busy international commerce has…
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 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 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 | 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 25, 2009Figure 1. For the 32 most-studied ant species, the percentage of publications 1984-2008 in various contexts.
In thinking about where the myrmecological community ought to devote resources in the age of genomics, it occcured to me that putting some numbers on where researchers have previously concentrated their efforts might be useful. So I went to BIOSIS previews and quantified the number of publications in 5-year intervals from 1984 to 2008 recovered under searches for various well-studied ant species (methods and full data here). Here's what I found:
Number of publications 1984-2008…
awild | January 15, 2009This weekend, Arizona State University is hosting a slate of myrmecologists to brainstorm on ant genomes. I'd link to the meeting information, but apparently the gathering is so informal that they've not given the event a web page. In any case, the topic is this: in the age of (relatively) cheap genomes, which ants should we sequence? And, what should we do with the assembled data?
I originally planned to attend, but life intervenes and I'm frozen to the tundra of central Illinois. Instead, I will register here a few suggestions about which species should considered, in addition to…