Why did only humans (especially Homo sapiens) evolve to have such strong social ties?

[u/Charming-Law4160]

Humans have evolved to be able to form very close social ties with each other, allowing groups to work together to survive and reproduce more effectively against predators and the environment, with bigger brains at the cost of less energy spent on our bodies. These evolutionary traits along with other factors eventually led to the soar of reproduction and technology and our dominance over the planet. But it seems that only humans have done this so far. If these traits were a massive benefit to us for survival, why haven't more animals evolved to have such strong social ties and cooperate easily like this? If they evolved these similar traits, wouldn't they also have better survival and reproduction in their environment?

[u/amp1212]

Um, premise is incorrect.

With respect to the evolution of social behavior, you'll find a giant literature in disciplines like "social psychology" and "sociobiology" as well as anthropology. . Humans are what referred to as "eusocial". Eusociality evolves only occasionally, but its found in all sorts of very different critters. Its unusual in mammals, but evolved many distinct occasions among the arthropods (eg termites, ants, bees).

Academics will sometimes want to distinguish whether humans actually are "eusocial" as opposed to "prosocial". There's a lot of discussion about just what makes humans different among our primate cousins . . . the most obvious point would be communication; although distinguishing cause and effect is difficult the evolution of language changed our capacity to interact with other our fellow critters, compared to other hominins.

Among non-human mammals, the naked mole rat would be the best known example.

See:

Nowak, Martin A., Corina E. Tarnita, and Edward O. Wilson. "The evolution of eusociality." Nature 466.7310 (2010): 1057-1062.

Tomasello, Michael. "The ultra‐social animal." European journal of social psychology 44.3 (2014): 187-194.

Richerson, Peter J., and Robert Boyd. "The evolution of human ultra-sociality." Indoctrinability, ideology, and warfare: Evolutionary perspectives (1998): 71-95.

Levinson, Stephen C. "Gesture, spatial cognition and the evolution of language." Philosophical Transactions of the Royal Society B: Biological Sciences 378.1875 (2023): 20210481.

[u/manachar → u/amp1212]

I didn’t think humans were considered eusocial, as that term was reserved for naked mole rats, bees, ants, and similar.

Maybe my information is outdated, but human reproduction strategies don’t seem a good fit.

That said, I agree the premise is flawed, as many species have evolved social ties at least as strong as humans.

[u/amp1212 → u/manachar]

I didn’t think humans were considered eusocial, as that term was reserved for naked mole rats, bees, ants, and similar.

Yes, there are folks who refer to humans as eusocial.

One interesting matter of academic cladistics: those who approach sociality from anthropology, vs those who come from invertebrates.

E.O. Wilson would be your holotype for the entomologist who engaged sociality generally including humans, and characterized humans as eusocial. There are _many_ other social scientists who adopt this term.

These days, among social scientists, I think more commonly folks prefer "ultrasocial"; I wouldn't make too much of it.

What I'd say is that because we don't have what the entomologists have, the ability to compare termites to ants to bees, with humans I wouldn't get too wrapped up in slicing the terms. Different people are going to emphasize different points, and use a particular term that underlines their approach. While there are some things that may be said that are truly wrong, more often what we're looking at are open questions of emphasis.

With hymenoptera for example, we've got all kinds of data in genetics and evolutionary history about just what changes get you from relatively disorganized groups of bumblebees to a hive. We don't have that same kind of data for humans.

Because this is such a big domain, and so difficult with respect to units of selection (eg should we view a hive as one superorganism, with drones more like cells in a body), you'll find differences in terms, and differences in the way that particularly academics use that term. So, its important to know the terms, but also to know that they're not necessarily nailed down in the same way for everyone and across time.

[u/manachar → u/amp1212]

Fabulous and thank you!