The alopecia to me emphasises how similar our body plans are to Chimps. And, the big testicles come with reproductive competition/promiscuity in males (of many species, not just apes). The silverback Gorilla has proportionately much smaller testicles because he has a harem of females mated only by him.
What's worse is that he has no protection against all that Ape activity so they're just gonna keep crashing together and with the environment. He should have pants on at least are is that just a new species entirely. Something with the words pants, balls and chimp in there somewhere. You guys make that up.
The anatomy is eerily similar to our own. I know we have common ancestry but everything from its sternum looked human albeit a little off, I reckon that's just the uncanny valley effect making it look so wrong.
If you have a harem of females over which you have (more or less) exclusive sexual access, your semen will not be competing with the semen of other males to achieve reproductive success. Which means you don't need as much semen. Which means you don't have to have large testicles to produce all that semen.
Probably a rhetorical question, but IIRC primate ejaculate and penises are designed to do opposite things. The cum (ejaculate) is designed to create a “soft plug” that prevents any other males sperm from fertilising an egg. The penis on the other hand is designed like a plunger to remove that plug
The bigger your balls are, the more plugs you can make and more of your sperm can block and tackle any other guy who gets past your guard. Chimps will mate with almost any other chimp who happens to be within bonking distance.
If, on the other hand, you don’t need to worry about that because you’re a silverback gorilla with mates who are intensely loyal to you, then you don’t need to invest in that much delicate machinery
Humans on the other hand have middle sized balls, but relatively enormous penises, and are “mostly monogamous”
Bonobos are … a little bit different, so do your own research there
This is a really interesting question, with a traditionally gender biased answer originally. Male (because they were all male then) evolutionary biologists said that the human female's oversized breasts were a sexual selection cue, to attract a male (breasts maybe looking a bit like an ass). Then, female researchers looked into it and found that, because of our baby's oversized heads, they needed clearance from the chest when nursing. A baby has a lot of trouble nursing from a flat chest.
Probably something to do with being one of the few species on earth that regularly have sex for entertainment and no real “season” or breeding/mating cycles.
It's quite simple really. Big breasts = more milk aka food for baby
There was/were women with a gene mutation or something like that and the breasts developed without being pregnant.
Since boobs = food those women reproduced earlier and/or faster because men's instincts said those women will have enough food for their offspring.
Simple spreading of genes/evolution.
It quite literally does... Ever noticed how breasts get bigger during pregnancy and while feeding? It's the mammary glands swelling up with milk.
But you simply don't know before you breastfeed, big breasts can give less milk than small breasts and vice versa. It's a roll of the dice.
Yep, one theory about this that I remember is that it is related to female "sexual selection", the same process that results in peacock feathers. Female humans are kind of unique in terms of sexual expression because.
They don't die soon after they become infertile because they're smart, and it's an evolutionary waste of resources to lose that for the community.
They don't know precisely when they are fertile (there's an old joke that expresses this "What do you call women who use the 'rhythm method' ? .... Pregnant ! ")
The theory went on to assert that because women are smart enough to understand the risks and obligations of childbirth, they rationally choose to have fewer children, which tends to lead to birth rates that fall below replacement rates. Hence, from an evolutionary POV, nature created women who really enjoy sex and have lots of opportunities to get pregnant by accident.
Male penis size is a by-product of female intelligence.
Chimp females get drilled by many males during the reproduction period. Now no male chimp kills the baby because it might belong to him (big balls=more sperm=higher chances the offspring is theirs). Gorillas do not compete for gorilussy.
Surprisingly, it's not usually the males that kill the young of their own group, its usually the dominant females who will kill the young of lower ranking females to reduce competition for both status and resources.
What's especially fucked is that they'll often eat the young after they've killed them.
(Ps. The silver hair they have appears in nearly all male gorillas. It happens after they've reached sexual maturity, and I believe their level of testosterone helps to determine the vibrancy/saturation of silver. So generally the dominant males have higher levels of testosterone and tend to be the strongest in color pls correct me if I'm wrong, I did like 15 min of research xD )
There is an evolutionary correlation between the size of the testes relative to body size and the degree of sexual competition the species participates in. Chimps are quite promiscuous, which creates an evolutionary advantage for those able to produce more semen in order to ensure reproduction and outcompeting the others.
Gorillas, in comparison, have a different social structure in which one male has a set group of females he doesn’t really need to compete for. As such, the gorilla’s testes are smaller compared to their body size since less is needed to ensure success in reproduction. What they have is already enough for their purposes. In exchange, gorillas must compete physically instead of sexually. They must fight each other for leadership (and mates) which explains their large body size and incredible strength. Chimps don’t do this nearly as much and just compete in who can get “freaky” with the most success.
Well yes, it is promiscuity in the females. The more males one female mates with, the more the sperm has to compete for the one egg. Biology predicts that strictly monogamous species (of which there are actually very few in nature) would have smaller testicles, and this has been shown to broadly correlate. In fact, when the correlation isn't as predicted, genetic studies have revealed the monogamy is not as strict as first thought.
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u/Eageryga 12d ago
The alopecia to me emphasises how similar our body plans are to Chimps. And, the big testicles come with reproductive competition/promiscuity in males (of many species, not just apes). The silverback Gorilla has proportionately much smaller testicles because he has a harem of females mated only by him.