As for cooperation "across genetic boundaries" within a species, I can think of lots without even having to search. Vampire bats sharing blood with unlucky fellow bats who didn't find anything comes to mind.
It seems that almost every time someone (often someone trying to make a point about human exceptionalism without having bothered to actually check if they're talking nonsense) makes a statement that "humans are the only creature to exhibit behaviour X", a counter-example is only a websearch away. I've come to strongly suspect that there isn't any special or unique quality humans have that no other species does; we differ only on the scale of some of them and perhaps got lucky with a few physical characteristics that lent themselves to additional uses (although that's very speculative; we built ourselves a society and a way of life perfectly suited for our shape and characteristics, so of course that shape and characteristics look really helpful).
Almost invariably capitalists try to define capitalism as being intrinsic to "human nature" or "society", and are always wrong. If you read the higher upvoted comments -- that statement is believed and taken at face value.
If you have to take the time to defend that your accumulation of material wealth is ethical when there are millions of people dying from a lack of resources... I don't know what to say. I just hope HN grows to stop believing the obvious lies.
Oh yes, lots. Here are some really interesting ones betweens species.
https://listverse.com/2015/02/23/10-amazing-cooperations-bet...
There are many more.
As for cooperation "across genetic boundaries" within a species, I can think of lots without even having to search. Vampire bats sharing blood with unlucky fellow bats who didn't find anything comes to mind.
It seems that almost every time someone (often someone trying to make a point about human exceptionalism without having bothered to actually check if they're talking nonsense) makes a statement that "humans are the only creature to exhibit behaviour X", a counter-example is only a websearch away. I've come to strongly suspect that there isn't any special or unique quality humans have that no other species does; we differ only on the scale of some of them and perhaps got lucky with a few physical characteristics that lent themselves to additional uses (although that's very speculative; we built ourselves a society and a way of life perfectly suited for our shape and characteristics, so of course that shape and characteristics look really helpful).