Thank you for finally naming the experiment I always cite when arguing homosexuality is natural population control.
It a nice piece of evidence for "environmental" conditions, though it's often missed they didn't start with an overcrowded cage. They let them breed to the overcrowding, to better study the change in behavior. When you add that it sorta fucks up the common 'real male' argument.
Especially the second one with mice instead of ship rats.
The experiment was stopped when conditions of the rodents became too extreme even for the ethical standards of the time. A second experiment was made in the 1970s with a 101-inch square cage and using mice, reaching a population about 2200 mice
I personally like the idea that hormonal levels in the mother trigger genes (predisposed towards behavioral traits) one way or the other. Hormones affected by environmental conditions (hormone overloads), as a mama rat had to breed some of those warped incel or asexual rats.
Another cool one is the successive born males to a single father. Which happened along those same, "Ok, nature say's that is enough breeding." lines.
Even the 3rd born male has a 50% chance of being homosexual along an increasing likelihood. So by logic alone the religion with the most homosexual males has to be The Mormons.
Our ape cousins are also interesting in proclivity. Find a great ape habitat at a zoo that isn't filled with a supermajority of bisexual animals. Faggot emasculated chimpanzees.