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Ok, let's ignore everything we know about males and females for now. So like males aren't
mustached beer drinking slabs of testosterone and it's possible to leave a girl alone with
your chocolate. Let's break it down to the basic definition
of male and female. What we call a male will be the genetic class
or genetic variety of a species that produces the smaller sex cell, the smaller gamete.
The female makes the larger ones. The females gametes move around less, they take more effort
to make and the females are almost always the ones that store the babies as it gestates.
So let's make two different communities. One is made up of 9 females and 1 male and the
other 9 males and 1 female. In terms of reproduction what might we see differ?
Well, in the first, the male could fertilize all 9 females... probably in the same day.
And then after, let's say 5 months for whatever this thing is, all the females would have
an offspring, and the male would have lots of offspring.
OK. What about the other community? After 5 months, only the female and 1 male will
have a baby. And then what, it's someone elses turn?
Creatures want to leave behind as many offspring as possible. And they could get killed by
falling rocks tomorrow, they really want to reproduce as soon as possible. They're all
going to want to breed and they're not going to want to share. So they'll fight over her.
This is a part of why all over the animal kingdom, you see the males being more physically
aggressive than the females. Because females are more of a scarce resource to male reproduction
than males to females. From the female's point of view, she can pick
whatever male she wants as a mate. She also wants to make as many offspring as
possible but because she can only produce 1 every 5 months, she'll be choosier with
whom she mates with than a male is. She'll want to pick a mate that can make children
that have a high chance of reproducing. Maybe the biggest or strongest? Since the biggest
and strongest win the mating rights among the males? And is maybe a sign that this guy
survives well and his kids will too. I'm not using the word "want", to say that
they necessarily literally want something. Like they're sitting there working what the
best strategy is for spreading their genes around.
Rather I'm personifying the genes or the individual as having wants as a short way of saying that
"everything else being equal, females that are genetically inclined to being attracted
to big strong males, will leave more behind offspring or offspring with a higher chance
of reproducing compared to females who are not attracted to big strong males ".
It's want in the sense that if that individual has a gene that codes for that thing, it will
reproduce more. So it can kinda seem like that's what genes
want to do. But there's a problem with this, saying that
genes directly control behaviour. Which isn't true right? There's no gene for say: driving
a car. Gene's do influence your arms, your legs and your brains that facilitate and create
the motivation for the behaviour. But saying that a gene controls a behaviour. It's a bit
incomplete. When dog breeder picks what dog gets to breed
based on what behaviours make a good pet, what they're really selecting for are the
genes that create a certain brain structure. But also a dog trainer.. can change that brain
structure and behaviour by training and controlling it's environment.
Is there even a genetic component to her mating with this big strong guy? Maybe it's entirely
environmental. Maybe he's just intimidated or even physically dominated her into mating.
Your genes and the things that happen to you are what shape your phenotype. You could have
some mutation that makes it so that you only have 1 arm. But you could also lose an arm
in an accident or something. Seeing a behaviour and assuming a gene directly influenced it,
is the same as seeing someone with one arm and assuming a gene directly influenced that.
It may be true, but we haven't demonstrated that.
I'll come back to this later maybe... for now let's ignore any environmental factor
and just look what the genes might do and assume: gene... boop... behaviour.
Let's look at 2 broad ways a community's social structure could evolve.
You could have just the one largest, strongest male intimidating everyone and mating the
females. Because he can fight and win to cock block any other males that tries to mate.
Animals with social structures like this could be described as a tournament species. Because
here you have one geneder, usually the males, competing for the favour of the other gender.
In a system like this you would probably get a minority of the males mating with all the
females. Since he's one if the few who gets to mate, and he's is probably one of the largest
and most aggressive, future generations will continue to have males that are larger and
more aggressive. That power may change hands often but still favouring the strongest....
or just the male with the most impressive display of health and strength and good genes.
So with a tournament species, you would expect to see a lot of sexual dimorphisms, a lot
of differences in the size shape and behaviour between the sexes.
You can even use sexual dimorphisms to predict the behaviour of the species. This is the
sort of thing you see in chickens, savannah baboons, lions, moose, gorillas, all have
males larger than the females and they all exhibit some sort of tournament system.
Because whoever is on top is too concerned with maintaining his alpha status, and they've
got too many kids to care about, the females do most of the raising of the kids alone and
tend to have evolved to only produce 1 child at a time. Otherwise they might have their
hands full and be able to give proper care to each of their children.
But you could have a completely different social structure. One where where both parents
are taking care of the kids. With more parental care the kids would have a better chance at
reproduction. And since the females have some help, the females would be able to produce
more than 1 child at a time benefiting their reproduction.
Since the males are busy taking care of kids alongside the females, you tend to get a larger
majority of the males mating, rather than spending their time jockying for alpha.
Since they're not fighting, and the females are selecting for parental care, he wouldn't
have evolved big useless muscle or dramatic features like colourful feathers and you would
expect to see less sexual dimorphism. This could be called a pair bonding species.
A good example of this is the marmoset monkey. You can't really distinguish the males from
the females by looking at their behaviour or their body unless you looked real close.
But pair bonding or tournament species, these are just more categories that category people
make. They're useful as very broad ideas for describing some patterns between social structure
and physiology. But they're not entirely predictive. In baboons, where the males are super aggressive
and can be twice as large as the females, there might be a subordinate male who's too
old or too weak to ever have a chance at being alpha. But he could approach a female and
groom her a lot and otherwise woo her with his parental skills and they may have sex
in secrete in a more pair bonding fashion. And you can have a situation where the entire
community that doesn't follow the "mating rights through violence" regime.
In spotted hyenas, it's the females that are larger dominant. Even the lowest ranking female
in their dominance hierarchy is dominant to the highest ranking male.
And I'm pretty sure every bonobo is just bisexual. Which increases their chances of getting a
date, but demonstrates there's more going. And what about humans? Human males are larger
and more physically aggressive than females and females produce single children. But most
cultures have some sort of monogamous marriage system. But again, a lot of marriages end
and we don't seem to mate for life. And females can be attracted to both dominant traits and
parental traits. Does she go with the muscular competitive guy who is genetically predisposed
to taking his shirt off, or the older more mature guy who has feelings and stuff....
or maybe both at the same time. Like a lot of species we would be somewhere
in between these 2 classifications. In reality it's not about tournament or pair bonding,
it's just whatever works.
So the decision becomes pretty straight forward: you gotta kill the kids... you just... you gotta kill em. You need that baby mama to be your baby
mama but she can't if she's already pregnant or maybe she's just lactating and won't ovulate
till she's done. If you're the mother you're going to want to protect your kids, but you're
not going to put of so much of a fight.....