This guest post is by Pleuni Pennings on the paper “Oh sister, where art thou? Indirect fitness benefit could maintain a host defense trait”, available from the arXiv here. This is cross-posted from her website here

Tobias Pamminger, Susanne Foitzik, Dirk Metzler and I analyzed the small scale spatial structure of ants of the species Temnothorax longispinosus. These ants are the host of a slavemaking ant. The slavemakers go on raids, and steal young from the host species to work as slaves in their nests. We wanted to know whether the slaves still have relatives in the nearby nests. If they do, then their behavior – which influences the slavemakers – could have an effect on their relatives and therefore on their indirect fitness.

To find out if slaves are related to their neighbours, we collected lots of ant nests (they nest in acorns), both in New York and in West Virginia, marked exactly where we found them and genotyped them at six microsatellites.

Photograph by Andreas Gros
Temnothorax longispinosus in acorn

We put little flags at the exact location of an ant nest to measure the distances between the nests.

This is one of the figures from the manuscript. Plot R (from West Virginia) is is shown to demonstrate the distribution of colonies within a plot and to show the distribution of alleles of one of the six microsatellite loci (GT1) among colonies. Each colony is represented by a pie-diagram with the frequencies of different GT1 alleles amongst the genotyped individuals of the colony. R3 is a slavemaker nest (we genotyped the slaves, not the slavemakers) and shares most of its alleles with the free nest R7. R13 and R15 are free living host colonies in close proximity and appear to be related.

Our main conclusion is that the enslaved ants are indeed related to their neighbors. The manuscript can be found on the arXiv here: http://arxiv.org/abs/1212.0790

The manuscript was peer-reviewed at Peerage of Science, a new and very useful community of scientists who agree to review each others papers fairly. See http://www.peerageofscience.org/

The manuscript is part of Tobias Pamminger’s PhD thesis. Tobias defends his thesis this week in Mainz!! Congrats Tobias!

Tobias came up with the awesome title for the paper “Oh sister, where art thou? Indirect fitness benefit could maintain a host defense trait.”