I really enjoy reading about these group dynamics. Usually people interpret the "it makes sense that people would do this" as meaning "self-interest dominates c

I really enjoy reading about these group dynamics. Usually people interpret the "it makes sense that people would do this" as meaning "self-interest dominates compassion" but I actually think the meaning is "those groups which did these things survive" and so over time you get these things built-in. "Compassion" isn't something I constructed for myself from rationality. I can do that, but it is a back-formation - an explanation for a behaviour I was already going to do. I'd say it's more of a property of my ancestry than my reason since I had it as a child in more or less the same form as I have it today and I recall my younger brother come back crying after going to help an anthill survive a storm (the ants were unreceptive to this Anti-Ender's assistance). At 4 years or younger he had no capacity for the kind of reason required to reach compassion tabula rasa. I model mankind as self-similar to man. Allocare makes sense between individuals in the same way that a T-cell 'cares for' other cells in the body. And Lawrence Oates's "I am just going outside and may be some time" seems akin to apoptosis: knowing the cost on the rest of the organism, the individual has programmed escape hatches that preserve the entire operation. It seems natural and adaptive that individuals will attempt to exploit the structures (care for the injured and elderly) that so arise. And counter-adaptations to that form as well. But evidence that agrees with one's model is usually not as useful as the evidence that disagrees with it and so the thing that I find most interesting is the chap with the massive hip dislocation. That's a debilitating injury or disability and for a tribe on the move it must have been a massive expenditure of resources to bring along this individual. If encountered in childhood, perhaps the net increase in resources is not that high. If encountered in adulthood, perhaps it was a prized member of the community or perhaps the group anticipated recovery. On the other hand, we do find good reasons to "protect the team". Knowing that you will be cared for means you give more to the operation. The classic "No Man Left Behind!" stance probably has a huge effect on morale.