Technically, humans are not eusocial, which by definition requires a biological division of reproductive labor. Most eusocial species actually have significant morphological differences in their classes (i.e. females that physically can or cannot reproduce).
Wilson tends to repeat the idea of humans and other primates as eusocial which I find confusing.
Eusociality and its evolution is indeed a fascinating topic. There are some great discussions on this from WD Hamilton (the study of led him to inclusive fitness theory and kin selection) and Richard Alexander (who discovered the only eusocial mammal - the naked mole-rat).
Wouldn't the biological division of labor regarding breast-feeding in humans be sufficient? It's a significant morphological difference.
Humans aren't eusocial, but we certainly have division of reproductive labor. So do non-social sexual species.
So, this led to some ant-related discussions with him. Did you know that ant colonies can have memories older than individual ants? (see this great Ted talk: https://www.ted.com/talks/deborah_gordon_digs_ants?language=...) The bizarre concept of eusociality also came up, how did such a thing involve? If ants (and termites and bees) are so successful with this strategy why wasn't it adopted by more species? According to https://en.wikipedia.org/wiki/Eusociality very few animals other than these exhibit eusociality (humans aside, which presents a complicated case).
There's fierce debate about the evolution of eusocial behavior, kin selection vs. other explanations. Wilson's theory presented in his 2010 Nature paper, co-written with two mathematical biologists [1], seems to be at odds with others and generated a strong reaction from other researchers [2] (see this Quora answer for a high-level intro to this technical discussion: https://www.quora.com/Does-EO-Wilson-Corina-Tarnita-and-Mart...).
My son is planning to put his mark on this debate in next year's science fair by trying to measure DNA similarity of worker ants from his colony :-)
[1] https://www.nature.com/articles/nature09205
[2] https://www.nature.com/articles/nature09836