Some of the skeletons that we've found from... basically the last ice age, some even further back, show humans (or proto humans) that had had badly fractured bones... but they healed up (not well by modern standards, but nonetheless), and then those bones grew, and the individual died at a much greater age than when the serious fracture occured.

... And these people are buried in graves, with grave goods, not just thrown out or left behind in the wild.

Strong evidence of early human groups actually giving enough of a shit about their members to take care of the wounded, helps to be able to date early societal formation.

https://kimwerkmeister.substack.com/p/the-first-sign-of-civilization-how

Empathy and responsibility to care for others are actually the literal foundation of human society and civilization, contra to Musk and all the fascists and Christian Nationalists recently claiming 'empathy is a sin'.

Kangaroos form two sorts of groups

1. Like most herbivores, they have one male and many females in a mob (kangaroo equivalent to a herd)
2. Males outside that mob form loose groups for defence and within that they fight to establish dominance and the top roo may challenge the male lead of a mob to take it over