A battle for the desert


Pogonomyrmex maricopa (at left) tussles with an Aphaenogaster albisetosa at the Aphaenogaster nest entrance.

While in Arizona, I chanced upon a set of ant fights that I'd observed several times previously.  Single workers of the maricopa harvester ant Pogonomyrmex maricopa would approach a nest of their competitor, Aphaenogaster long-legged ants, and spend a few minutes drawing heat from the guards before wandering off.


Same thing, but different individuals (note differences in limb wounds from the previous photo)

The interaction is common enough that it really couldn't be just a chance encounter.  Are the Pogos doing this for a reason?  Are they distracting the Aphaenogaster from foraging?  And, are there any myrmecology students in Arizona who need a little research project? It'd be great to figure out the purpose of the fights.


Three on one.  Do the Pogos subject themselves to this treatment as a decoy, to draw Aphaenogaster away from shared foraging territory?

photo details (all photos): Canon mp-e 65mm 1-5x macro lens on a Canon EOS 50D

ISO 100, f/13, 1/250 sec, twin flash diffused through tracing paper

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Interesting observations and great action shots! If these competing ants are active for the same parts of the day, I wonder if the Pogos are scouting out rival colonies' activity at certain times? Would make an interesting little project, that's for sure.

whow, these are the action shots that make a heart thumb faster. Very sweet observation and nicely caught onto the digital film.

Couldn't the behaviour be like testing "the lines" ? Like if there is little resistance, it's good to attack, else back off ? I thought there were a few insectspecies around that use that tactic.