yes, a defendable nest seems important for many lineages. Researchers (e.g., Strassmann and Queller 1998 academic.oup.com/bioscience/a...) have argued that there are two main ways of being eusocial: fortress defenders and life insurers.

The signal was driven by a single lineage: the aculeate Hymenoptera (stinging wasps, bees, ants). Outside that lineage, haplodiploid insects did not evolve eusociality faster than diploids. The apparent association between haplodiploidy and eusociality is not a general property across insects. 11/13

At first glance, the data seemed to support the haplodiploid hypothesis. Across insects, we estimated nearly 2x as many independent origins of eusociality, at approximately 7x the transition rate, in haplodiploid lineages as in diploid lineages. But… 10/13

Meanwhile for >40 years, most empirical researchers have doubted the hypothesis. Further, some researchers (incorrectly) claimed that an apparent lack of evidence supporting the hypothesis amounted to evidence against inclusive fitness theory more generally. 6/13

Interestingly, over the last 50+ years, theoreticians have developed an array of increasingly sophisticated models for how and when haplodiploidy might facilitate the evolution of eusociality 5/13

But almost immediately, theoreticians noted important complications. Haplodiploid females are related to their brothers by only r = 0.25, so that on average, full sibs are equally related to each other and their offspring, just as in diploids. 4/13

Could one of life’s major transitions (solitary-> eusocial) be predicted by patterns of genetic relatedness? Inclusive fitness theorists said yes! Hamilton (1964) proposed that haplodiploidy could promote eusociality because haplodiploid full sisters are relatively closely related. 2/13

Heard of the haplodiploid hypothesis (=¾ relatedness hypothesis)? It’s long been a staple of biology textbooks – you may’ve run into it in Intro Biology, Genetics, Evolution, or Behavior. It’s also been very influential on social evolution theory, yet surprisingly, it long remained untested.🧵

Oops, those are flies, not honey bees!

Species vary more in behavioral space for activity cycles at the collective level (pink area) than at the individual level (blue area) 5/

We estimated rates of behavioral evolution across our phylogeny and infer that collective behavior evolved more rapidly than individual behavior. 4/

Colonies of ants show regular bursts of activity over time. Individual ants also have these activity cycles, and ant species differ for these individual- and colony-level activity cycles. 3/

Collective behaviors are striking, widespread, and can emerge when individuals follow simple interaction rules. How does collective behavior evolve? New paper @pnas.org led by postdoc Grant Doering www.pnas.org/doi/10.1073/... 1/

my "hot take": carefully thought out and carefully written perspectives that "create new discussions, inspire future research, and maybe stir things up a bit" ...that's all great and I'm definitely looking forward to these new articles. But actual hot takes don't belong in a leading journal.

and also this:

interesting that they make this assertion: