> It's expected some cooperatio, but also some treason and backstabing.
That wouldn't be surprising, but I don't know if that is true.
I wouldn't not be surprised either way. A species survives not because its individuals do but because its genes do. Taking all available genes and spreading a subset of them amongst sperm-cells randomly is an interesting strategy.
It might be even optimal because the traits of a sperm-cell that make it survive during conception are not the same traits that help an individual thrive outside the womb.
If the 'fastest swimming' sperm-cell would always win, it would mean that in future generations faster and faster sperm-cells would win, but that would not necessarily help the survival of the species.
Each sperm has a different DNA, they are like siblings. It's expected some cooperatio, but also some treason and backstabing.
[1] Ignoring some interesting cases.