Behavioral Ecology Blog

OK, so jury duty unfortunately means that I have not been keeping up on current literature.. So, this paper: Wasp Gene Expression Supports an Evolutionary Link Between Maternal Behavior and Eusociality from the 27-Sept issue of Science was missed completely…

Before I get into the paper, I want to rant for a minute about “Next generation” sequencing. So I am a Behavioral Ecologist, and generally study behavior at the level of the population or species. For example, while reproductive behavior surely varies at the level of the individual, more interesting are the patterns of behavior that emerge at higher levels. So while whole genome scans are becoming more available, it’s utility for me seems limited at best. In a nutshell- there won’t be 45MB of DNA sequence data (a 454 run) in my near future…

Th’s being said- the U of Illinois researchers have used 454 and the Apis genome to do something pretty cool. Here is what they did:

1. Characterize behavior of 4 different worker castes in Polistes and ID a bunch of individuals of those particular castes.
2. Wait for the Apis genome
3. ID a set of genes that are related to maternal care
4. Get the cash money for the 454 run using Polistes cDNA
5. ID those maternal care genes in Polistes using the Apis genome
6. Measured gene expression for these genes in the 4 castes
7. See which groups were similar using LD and some strange clustering analysis.

Turns out, the workers (provide sibling care) are really similar to Foundresses (provide maternal care) in their patterns of gene expression. But does that mean that maternal care and eusociality are mechanistically related?? They claim yes, and maybe I would too if I too thought that the only thing that made eusociality noteworthy and different than other things was sibling care.. There are a whole shit-load of cooperative breeders… If these genes are associated specifically with eusociality and not just care-giving, then care givers in cooperative systems should be distinct from eusocial care givers..

For me, it seems like this is another example of overstating conclusions.. I’ll not deny that it is cool, and that we should be excited about this, but just because the same set of genes seem to regulate maternal care and sibling care does not mean that maternal care is so tightly linked to eusociality- especially in Polistes- a wasp genus that is not all that eusocial. Now I’d be alot more excited if this same study was done in some eusocial Hymenoptera or in mole rats, and if knockout experiments dissolved colony structure…

Basically, if sibling care = eusocialiy, then their conclusions are right on…otherwise, not so much, at least not until more work is done…

Oh hell, what the heck do I know, it got ‘em into Science I guess..
Toth, A.L., Varala, K., Newman, T.C., Miguez, F.E., Hutchison, S.K., Willoughby, D.A., Simons, J.F., Egholm, M., Hunt, J.H., Hudson, M.E., Robinson, G.E. (2007). Wasp Gene Expression Supports an Evolutionary Link Between Maternal Behavior and Eusociality. Science, 318(5849), 441-444. DOI: 10.1126/science.1146647