OK we all have seen it. 2 of Gods little creatures getting ready to go at it and make some more of Gods little creatures. I was watching 2 squirels run past. The ritual seems to be (with some assumptions):
1 Female goes into heat - releases pheromones
2 Male senses this and gets horny
3 Male runs after female
4 female runs away from male
5 Male catches & mounts female
6 The stork deliveres a load of baby squirls to the moma
OK I can see some logic in the male having to be physically fit to be worthy of having his genes past on, but it would also seem that the slow female would be having the most sex (and most babies), and the really really fast females would not be getting any and their genes would be lost (no babies).
So evolution would give pressure to fast males and slow females. What am I missing here?
I’ve seen something like that with Mallard ducks. Usually, though, it’s more like:
1 Female goes into heat - releases pheromones
2 Male senses this and gets horny
3 Male and female do courtship behavior
4 Female crouches and says, “Take me now, you gray, bushy-tailed stud!”
5 Male mounts female while female chatters gleefully
6 The stork delivers a load of baby squirrels to the momma
I imagine it also has something to do with the slower female squirrels becoming dinner for fast predators, and thus never getting around to having babies.
I’m reasonably certain that the female squirrel wants to be caught by the male and is just playing hard to get but not TOO hard to get. Why do I say this? Because predators aren’t picky and more often than not the slowest animal will become the next tasty snack. It is very much in the species’ interest that they all be very fast when the need arises.
maybe the reason why males are stronger is that males have to fight each other for females? then whoever wins takes the female. the female though can’t just “rape” a male, thus no point for female to be strong.
Is it possible that the females run to see if the males are strong/fast enough to catch them? that way the females could be sure that their children could have good genes.
Yes: the female chooses one male, and makes sure he gets her. When outside eating lunch once a couple friends and I watched a pair of pigeons cavorting-- not actually in the act, but one was clearly chasing the other, but the one being chased was only taking short 30-foot flights. They’d then land and look at each other from about ten feet apart for thirty seconds or so, and then take off again. We assumed that (since it was spring) the leading bird was female and the trailing bird was male. Whenever a third pigeon would show up and land anywhere near the pair, she would immediately fly and land within 1-2 feet of her chaser, making sure her chaser was between her and the third bird. The male would them challenge off the interloper, while the female hid a foot or so “behind” him. Because of where we were seated, we could watch this happen consistently over an area of urban landscape about the size of a football field, many times over a half-hour or so. It was cute to see, and it was surprising how deliberate it all was.
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In most species, females “invest” more energy in the production of young than males do. Eggs/ova are much larger than sperm, and cost more energy to produce. In the case of mammals, females obviously invest much more energy in pregnancy and lactation, and usually care of young, than males do.
It is for this reason that females are “choosier” than males are. Females will maximize their reproductive return by picking the highest quality males. Since they are generally able to produce many fewer offspring than a male, it pays them to shop around for the best one available - and make him prove himself by going through energetic mating displays, chases, combat with other males, etc.
Males, on the other hand, invest little energy in sperm. They will often maximize their reproductive return by mating with pretty much anything that moves. Therefore males will try to mate with just about any female around, and the race may often be to the swift (or sneaky).
Another thing . . . the actual top speed of males or females is determined by what’s necessary to elude predators. A female that is slow by nature is going to end up as hawk chow, not a mama squirrel.
One other thing about squirrels specifically is that the “mating chase” you mention is a rather ritualized part of courtship. The female squirrel in fact will not ovulate unless she has taken part in a vigorous chase by a male, and for this reason squirrels cannot be bred in small cages.
OK it seem that the part I missed is she’s playing hard to get and really will allow herself to get caught if it’s the right male (as she sees it). It makes a little more sense now.
