It’s is... some species exploit it:
https://en.wikipedia.org/wiki/Cuckoo
There is very obvious evolutionary necessity for familiar love. Social bonding is not the same as familiar bonding. A species can have one, but not the other.
https://en.wikipedia.org/wiki/Human_bonding
Hope... fading..... fading......... fad..........In 2003, a researcher from Northwestern University in Illinois found that progesterone, a hormone more usually associated with pregnancy and maternal bonding, may also control the way men react towards their children. Specifically, they found that a lack of progesterone reduced aggressive behavior in male mice and stimulated them to act in a fatherly way towards their offspring.
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Don’t want to name it, because of recreational use... but, there is a neurotoxin that causes the releases of more serotonin than you can ever naturally experience. Enough of that, is objectively the best sensation in the world.