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Mating rituals are various behaviours, serving as a precursor to copulation in almost all animal species. In general these serve to aid the females of the species to pick out a mate. They can be interpreted as tests or demonstrations of the male's (mental and/or physical) fitness.

Now one example of a mating ritual, practiced by many animals including deer and elephants, is chasing. It consists of the male chasing the female for sometimes several hours until the female allows the male to "catch" her. It's important to note that this "chase" is typically entered/initiated willingly by the female, she's not simply trying to get rid of unwanted attention.

Now my question is if it would be possible for an animal species to do the opposite. Could, there be an animal species where the female chases the male?

I want to make it very clear at this point that my question isn't about whether the inversion of sexual selection roles (in where females instead of males compete for the latter) is possible: indeed it is, for instance it's the dominant model undertaken by spotted hyenas, and it often happens in human beings.

My question is about whether there could be an arrangement where the females of a species chase the males as a test of the males vigour. Or in other words a mating ritual in which the male attempts to outrun the female as a demonstration of his stamina/agility.

So to conclude my main question broken down would be:

  • In what way (if any) could this inverted chase ritual be beneficial?
  • Is it a behaviour that could have plausibly evolved?
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    $\begingroup$ I recon you can more or less invert any biological mating rituals judging by physical size and strength of the both ahem... sides. But that's not what you want. Now imagine a mating ritual, where the male tries to run away from the female to prove whatever. What happens when he fulfils the criteria and succeeds? He has successfully run away from the female, he proved himself worthy, now he can mate with... er, sorry, with whom? $\endgroup$ – Oleg Lobachev Dec 24 '17 at 1:28
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    $\begingroup$ @OlegLobachev At some point, when the female is satisfied with the male's abilities, she can stop running and the male can then stop too. The point isn't for the male to completely escape the female, simply stay ahead of her. $\endgroup$ – AngelPray Dec 24 '17 at 1:54
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Is it a behaviour that could have plausibly evolved?

You need to give the male some reason to run. Usually, I think that this behavior involves several males chasing one female. The winning male would have demonstrated superiority over the losers. But with the typical male, it wouldn't make sense to reverse this. The optimal male approach would be to try to impregnate all his female chasers. So a single chaser would never develop.

This works for a female being chased by males because she can only be impregnated by one male comfortably. The winner can fertilize as many offspring as she can support. Reversing this doesn't work, as the female can only offer so many children.

To get this, you need the males to engage in some sort of female-like behavior. For example, in seahorses, it is the males that get pregnant. They fertilize a single batch of eggs from the female, which are then stored in a pouch in the male. As a result, the male can't simply spray his semen wherever. He has a real obligation after sex.

Consider something like a kangaroo, where the egg or infant is put in a pouch carried by the male (rather than the female as real kangaroos do).

Note that both the female and the male are engaging in significant effort here. The female is producing the egg, which is resource intensive. The male is safeguarding the fertilized result, which can also be resource intensive.

In what way (if any) could this inverted chase ritual be beneficial?

If the male escapes the female, then she would seem to be too weak to produce good offspring. He's better off looking for another candidate. If the male is caught immediately, then she may reject him for another, studlier male. If they can both maintain a chase for the same length of time, then they are compatible parents. The offspring will get about the same amount of strength from each parent.

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  • $\begingroup$ That doesn't sound like a stable system. If the weak mate with the weak, and the strong with the strong, then the population would quickly split in two. $\endgroup$ – Karl Dec 24 '17 at 10:48
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    $\begingroup$ Presumably a weak/weak pairing would produce offspring who would not survive. $\endgroup$ – Brythan Dec 24 '17 at 12:09
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    $\begingroup$ Interesting that with your two examples, seahorses and kangaroos, it's the males that gestate the young. An aggressive (fe)male is likely to violently usurp a rival's young to supplant their own. IMO, whichever of them carries the young to term is the one who has to do the running. Evolutionarily, if they can't catch you; you don't want them anyway, and vice-versa. $\endgroup$ – Mazura Dec 24 '17 at 20:10
  • $\begingroup$ @Karl and the weaker population would be culled off. That's a very good system when dealing with natural selection on the wild and reinforces the better fit population. $\endgroup$ – T. Sar Dec 26 '17 at 10:04
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The male could be killed by the mating ritual

There actually exists some mating rituals were the male systematically gets eaten after or even during mating. For example mantises and some species of spiders (where females are bigger than males) do this.

In those situations, the male generally doesn't run but if you consider a species where males are much more common than females, running away from her would be beneficial because it would:

  1. Make sure the female only mates with the most enduring male since after chasing him she would be too tired to run after another one, her only option would then be to finally mate then stop the chasing.

  2. Stop the female from killing all males in the vicinity by making the process a little more difficult.

If you imagine that the female of the species has sudden outbursts of this feeding/mating species, this kind of mechanism seems like a plausible result of evolution.

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    $\begingroup$ Your first conjecture doesn't hold. It makes the strong-strong pairing much less likely. A strong female would be able to mate will all the weak males, plus the strong males. A weak female would only be able to mate with weak males. This biases the selection to a weaker offspring. The truly strongest males would get away from all the females and never procreate. $\endgroup$ – Stephan Dec 24 '17 at 22:15
  • $\begingroup$ It would work in a setting where females only mate after they've finnished feasting and if you make the male inherently weaker than females (as is the case in some known species) even the stronger males could not outrun strong females for very long. $\endgroup$ – user44285 Dec 24 '17 at 22:21
  • $\begingroup$ I guess it could also work if either the males had to compete for the right to be chased, or the females chase groups of males simultaneously. Only mating with the fastest one. $\endgroup$ – Stephan Dec 24 '17 at 22:27
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Not sure if this is quite the same, but perhaps the leading-away bit might be more important than the chase or the test of vigor.

I'd thought, the male might use the chase to lure the female away (from something)...leading directly to the question of what they needed to be led away from and why it was advantageous enough they would stick around often enough to require luring from the males.

So, one option I thought of was, have the females in packs - perhaps all the time, or during season. There might be any number of advantages, from cooperative hunting to mutual defense, that would encourage such packs to form. I think having them seasonally pack up might work better, since I think they'd be less likely to have an established hierarchy than if they ran together year-round, doubly so if travel (between areas or else between female packs of an area, somehow) was not unknown.

So the way I picture this working is, there's a strong mating drive when the females are in season. A female witnessing a mating close to them may act aggressively, go and interrupt the mating - possibly injuring one of them - since the other female is competition for males, and any offspring would be competition for their own offspring. It would probably start off as a pure dominance play, so that only the strongest females in a pack mated (those that could prevent interruption), with males luring the females away from the pack being a way to game the system, so to speak.

In this scenario, a male that lures a female further from the rest of the pack before being 'caught' would have better chances of mating without being interrupted or dealing with aggression from other females, possibly injuries. A female that catches their male early, closer to their pack territory etc, will have a better chance of getting back to the pack and possibly interrupt other females mating, giving more chances for dominance, a higher position in the pack (possibly a larger share of food), and/or less competition to their offspring.

One possible consideration that could drive behavior in a different direction would be to have males wait out of range to ambush those that were leading females, and fighting to mate the lured female (with the challenger presumably less tired than the one who was chased). This could be minimized by having the female respond better to a male they chased (due to some courtship signals, etc at the beginning or during the run) or else have a higher chance of them being aggressive with a male that attempts to interrupt much like they would be with a female attempting to interrupt, as a callback to the times when breeding rights were a dominance issue to the females.

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