#AnimBehav2021 What explains diversity in mammalian social systems? Biologists have emphasized the roles of oxytocin & vasopressin (OT&AVP), two closely related hormones with a ~600 million year history. These pleiotropic hormones recurrently feature in reproduction & sociality

Part of the case for OT&AVP stems from comparing rodents with divergent mating systems: e.g., the ‘map’ of OT&AVP receptors differs between monogamous and polygynous vole species. This & other influential work suggests that pair-bonding has a biological signature #AnimBehav2021

But, there are challenges to the robustness & translatability of this paradigm. We present a powerful test of the above ideas using the only comparable ‘natural experiment’ in primates: the genus Eulemur, which contains both monogamous and non-monogamous species #AnimBehav2021

We obtained 12 brains from 7 Eulemur species and performed competitive receptor autoradiography to isolate locations of OT&AVP receptors. Two main questions: 1) is there a ‘lemur-typical’ map of OT&AVP receptors; 2) does this map differ between mating systems? #AnimBehav2021

For 1), we think the answer is yes! A cool takeaway: we find binding patterns reminiscent both of olfactory-guided rodents, and visually-oriented anthropoid primates, consistent with lemurs occupying an intermediate evolutionary niche between these groups. #AnimBehav2021

2): Surprisingly, we don’t see evidence of a pair-bond circuit akin to previous studies. Eulemur shows widespread inter-individual variation, unrelated to mating system. Non-traditional species can surprise us & challenge existing assumptions re: biological signatures of monogamy

I’m bending the rules a little bit & adding a 7th tweet to tag some of my wonderful co-authors ( @AnnikaSharma @SaraFreeman @BalesLab) & link to a preprint of the paper: https://osf.io/6gkc8/  Here’s another lemur picture for making it this far. Thanks for reading! #AnimBehav2021

That's what I get for trying to write down my co-authors' handles from memory--sorry, friends! Take 2: @EvNeuroNerd @BalesLab @SaraFreemanPhD