ants
awild | August 29, 2008
Juergen Heinze has a must-read piece in the latest edition of Myrmecological News about how ant colonies are not often simple families as we like to think of them:
Abstract: The social systems of ants are far more variable than has traditionally been believed. In addition to variation in queen number and queen mating frequency, recent research has documented such bizarre phenomena as the parthenogenetic production of females from unfertilized eggs or genetic caste determination. All these affect the genetic structure of ant societies, and it appears that in a large percentage of species…
awild | August 28, 2008
A perpetually happy Venezuelan Leptogenys
We don't really know why some species of Leptogenys hunting ants sport a permanent grin. The oddly ecstatic mandible shape might, however, have something to do with handling the broadly curved exoskeleton of their preferred prey: isopods (the sow bugs and pill bugs).
Flickr user "venwu225" recently uploaded a fantastic series of the related species L. falcigera in action. Some of the shots show how the mandibles allow the ant to grip the isopod both above and below its wide skirt of armor. Cool stuff.
photo details: Canon MP-E 65mm 1-5x macro…
awild | August 21, 2008
On my recent visit to the coastal forests of Kwazulu-Natal I noticed basketball-like growths on many of the Acacia trees. In North America, any large gray ball you see hanging off a tree branch is liable to be a hornet's nest. In South America, it's probably a carton nest of fierce little Azteca ants. The equivalent in South Africa? I didn't know.
A little bit of poking around in the acacias revealed the culprit. It was Crematogaster tricolor, an orange ant about half a centimeter long:
They didn't appreciate the disturbance, apparently, because they came after me without…
awild | August 18, 2008
Both nature and nurture control caste development in harvester ants, forthcoming in The American Naturalist. (via Physorg).
An ant slave rebellion? Temnothorax often kill their Protomognathus captors.
awild | August 17, 2008
Tetramorium sericeiventre
2008, Canon MP-E 65mm macro lens, MT-24EX twin flash
One nice thing about my recent trip to South Africa was that I could revisit the same species I shot on my last visit in 2003. Only, with decent equipment this time around. Check out the difference between the SLR (above) and the little coolpix digicam (below).
Tetramorium sericeiventre
2003, Nikon Coolpix 995, onboard flash
An obvious contrast is the stronger magnification of the SLR system, but I'd hold that the most important aspect is the flexibility of the off-camera flash, allowing for tight control over…
awild | August 16, 2008
Dorylus helvolus, KZN, South Africa
Last night the internet arrived at our new house. I've celebrated the occasion by tackling the backlog of photo uploads.
Over at myrmecos.net the South Africa photos are starting to go up. The first batch covers Dorylus helvolus, a subterranean predatory ant. Meanwhile, the fine art galleries at www.alexanderwild.com have also been beefed up with new material, including some stylized ant portraiture and the first of the Illinois scarabs.
On an unrelated note, Jo-anne has been sending along updates from the famous Ant Course in Venezuela. Word is that…
awild | August 12, 2008
This shot wasn't too difficult. The ant was following my finger about menacingly, as seen here, so I only needed to lift my hand just above the viewing frame to get her to pose.
awild | August 11, 2008
Asphinctopone differens Bolton & Fisher 2008
A new species from the Central African Republic
Bolton & Fisher Revise Asphinctopone (Zootaxa)
Shattuck Revises the Indo-Pacific Prionopelta
All imported Fire Ants in the U.S. are descended from 9-20 initial foundress queens
[summary in ScienceDaily]
ZooKeys: A new open-access journal for biodiversity & taxonomy
awild | August 10, 2008Our yard here in Champaign is about the size of a postage stamp, but it is in an older part of town and the ant fauna isnât half bad. In moving up from Tucson Iâve traded my desert harvester ants for a more midwestern fauna. Hereâs what I uncovered yesterday in a few minutes of looking around:
Camponotus pennsylvanicus
Camponotus nearcticus
Lasius neoniger
Formica pallidefulva group sp.
Paratrechina sp.
Tapinoma sessile
Myrmecina americana
Tetramorium âsp. Eâ
Ponera pennsylvanica
As a rule of thumb, older parts of town are better for ant diversity than newer developments. Iâve found this…
awild | August 6, 2008
Euprenolepis procera
(photo by Witte and Maschwitz)
This is cool. A new paper by Volker Witte and Ulrich Maschwitz details a previously unknown behavior for ants: nomadic fungivory. Here's the cite and the abstract:
Witte, V. and U. Maschwitz. 2008. Mushroom harvesting ants in the topical rain forest. Naturwissenschaften, online early.
Abstract: Ants belong to the most important groups of arthropods, inhabiting and commonly dominating most terrestrial habitats, especially tropical rainforests. Their highly collective behavior enables exploitation of various resources and is viewed as a key…
grrlscientist | August 6, 2008tags: white-tailed sea eagle, behavior, fetch, streaming video
Are you suffering from a problem with ants? Perhaps you should check your scanner to see if they've set up housekeeping in there? [1:19]
awild | July 31, 2008
Harpegnathos saltator - Jumping Ant
I thought I would have to travel all the way to India (the horror!) to photograph one of the world's most charming insects, the jumping ant Harpegnathos saltator. But I recently learned that myrmecologist Juergen Liebig, a professor at Arizona State University, maintains dozens of captive colonies in his lab in Phoenix. Juergen studies these ants' rather unusual behavior. Unlike most ants that show a clear division between reproductive queens and sterile workers, Harpegnathos workers can mate and produce fertile offspring, leading to soap opera-style…
awild | July 21, 2008Oecophylla weaver ants are exceptionally cooperative subjects for photography, allowing for plenty of experimentation with lighting while the ants preen and pose. While developing the photographs from South Africa I discovered that strong backlighting allows a crystal-clear view of the tracheal system:
Oecophylla longinoda, St. Lucia, KZN, South Africa
The tracheae are visible as dark canals running through the body. These connect to the outside air in a series of circular spiracles and are essentially the lungs of the insect, channeling oxygen to the respiring cells and carrying away…
awild | July 17, 2008
Leptogenys attenuata
In spite of the southern winter, the coastal forests of Kwazulu-Natal had plenty of ant activity to keep me occupied last week. In addition to the beautiful Polyrhachis I posted earlier, here are portraits of a few of the species I encountered.
Crematogaster tricolor
Platythyrea cooperi
Myrmicaria natalensis
Plectroctena mandibularis
Anochetus faurei
Oecophylla longinoda (African Tailor Ant)
Cataulacus brevisetosus
Dorylus helvolus
Pachycondyla (Bothroponera) mlanjiensis
Atopomyrmex mocquerysi
Pheidole megacephala (Big-Headed Ant)
Solenopsis geminata (…
awild | July 17, 2008Among the more charismatic ants I saw during my visit to South Africa was a silver Polyrhachis that seemed all too happy to pose for me. With such an unusually cooperative subject, I was able to experiment with several different arrangements of the flash heads on my MT-24EX twin flash. Compare these two shots, differing only in the placement of one of the two heads:
Polyrhachis schlueteri, St. Lucia, KZN, South Africa
The top photo is the clear winner. The MT-24EX has detachable heads, and what I did here was remove one of them and hand-hold it under the leaf, facing upward at the ant.…
awild | July 16, 2008Who was that waspy-looking male ant I posted last week?
Cephalotes rohweri, the Arizona Turtle Ant. Workers like like this:
awild | July 8, 2008
After a stroll through a Palo Verde woodland in the Tucson mountains I returned to my car to find this male ant sitting on the roof. I didn't immediately recognize it, and several hours later, after I figured it out, I wished I'd stuck around to looks for queens. What is it? I'll provide the answer next week.
Update: the answer!
awild | June 27, 2008
Yesterday's unexpectedly intense monsoon storms brought several inches of rain and flash floods to Tucson. Many of our desert ants cue their mating flights with the onset of the summer rains, and this morning the Forelius were flying, congregating in dense swarms that twirled and twisted above the desert floor.
Males emerge from the nest, ready to go:
photo details: (flight photos) Canon 100mm f2.8 macro lens on a Canon 20D
ISO 100, f/2.8, 1/800sec exposure
(close-ups) Canon MP-E 65mm macro lens on a Canon 20D
ISO 100, f/13, 1/250sec exposure, twin flash diffused through tracing…