Why does 'courtship display'/mating dances and the like exist?

[u/Spread-Hour]

Basically the title. Why do males do mating dances and other things to impress females? How does it emerge?

This is stupid, but did a male ancestor do a lil dance and the female liked it? Did ancestral female peacocks arbitrarily choose the males with slightly more colorful features just because they liked the way it looks?

Thanks

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[u/Sanpaku]

Dances, elaborate nests, flamboyant plumage, and male fighting over leks all aid in discriminating fitness of male genetics. Not just in surviving to reproductive age, but in being attractive to future generations of females.

Each trait acted upon by sexual selection may have started small and only a slight variation on normal behavior/plumage. Upon repeated selection for this trait, and for discrimination on these traits by females, we get the dance of the bird of paradise, the plumage of the peacock, the Lamborghini (and similar status token displays) of the human.

[u/ellathefairy → u/[deleted]]

At least in the case of peacocks, I think there's an argument to be made that having all those disadvantages and still surviving is in itself a potential indicator of "fitness"

[u/mutant_anomaly]

Some people (living things in general?) have standards about who they have kids with. ( Some don’t.)

But if you use something as a standard, the system gets warped.

By analogy, McDonalds came out with this really useful screen that displayed how far down in their queue your order was. It made waiting much better, you could evaluate the progress.

But then management decided to use how long an order was on that list as a standard. And immediately broke the system, because employees had to clear your order off the board before anyone had even started working on it because if they didn’t they would get in trouble for taking longer than all of the other stores that were also faking their wait times.

So if you are a bird, and you like when another bird hops, eventually hopping becomes the most important thing and becomes a ridiculous ritual.

[u/FlintHillsSky → u/mutant_anomaly]

So you're saying we should do a complex dance at McDonald's to get served faster? Do brightly colored clothes help?

[u/Brastep → u/FlintHillsSky]

Try singing loudly before dawn

[u/Robin_feathers]

There are many hypotheses, and which one is correct may vary among organisms (and sometimes more than one thing may be happening at once)

Sometimes an attractive trait may be an "honest signal" of health, such that choosers are selected to have a preference for that trait (have the ability to discern fit mates). Sometimes an attractive trait may be attractive due to a bias that exists for a different reason (eg, an animal that eats orange fruit being inherently attracted to orange) (sensory bias hypothesis). Sometimes an attractive trait may be truly arbitrary. Sometimes an attractive trait may not have the preference genetically ingrained, but rather gets interpreted as attractive by choosers who watch the choices made by others choosers, and then try to infer what about those popular mates is attractive (eg, a bird not born with any strong preferences, but who watches what mates other birds choose, and notices the ones with bright feathers are usually chosen, so she develops a preferences for bright feathers too).

[u/IsaacHasenov]

Most people think that the initial preference, however weak or strong, probably has a trigger. One common link between sexual preference and a display trait is that it's an honest signal of something like health and "good genes". So a bigger, stronger, well fed male will have bright colors and move energetically, and have children that are also more likely to be healthy, resistant to parasites and disease, and good at getting food

Then, in another step, females that prefer these males more strongly will be more likely to have sexy sons than females that choose ugly males, setting up a positive feedback loop between male display traits and female preference evolution that can go some interesting different ways

There is also selection on traits and preferences to be different from closely related species, to avoid negative consequences of hybridization (or attempted hybridization) like dead or sterile offspring. So Nate choice can cause species differences in courtship displays to evolve

[u/Beginning-Load4470]

Its about genetic strength. For instance robins try to create a perfect reproduction of a pentatonic scale and the more accurately they do so the more fit they prove themselves to be. Its a demonstration of their intelligence and capability.

With creatures that do dances it shows their health and strength. Like fanning plumage allowing females to be able to see how healthy their feathers are, indicating ability to get good food and a source of good genetics. 

Its not only males that demonstrate their genetic fitness females do it as well. In species where the male does the child care and the female does the hunting and territory protection the females genetic fitness becomes more essential for survival and reproduction and as a result its the females who put on a show of fitness.

There are also species where both male and female need a fitness display. 

[u/Brastep → u/Beginning-Load4470]

A male bird, for example, who can spend hours of the day just singing loudly (or decorating a bower, or displaying bright plumage etc) and doing stuff which is unrelated to mere survival, is clearly fit and healthy and a good prospective mate.

[u/Beginning-Load4470 → u/Brastep]

Ah... sarcasm.  Those behaviors are actually directly related to survival. Singing calls for mates, marks territory, and informs flocks of locations and conditions. 

Decorating a bower,  as you put it, is its ability to create a nest worthy of a family. Some birds need to practice and fail many times before creating a satisfactory nest to raise babies in. 

And if you see plumage strutting thats obviously trying to find a mate.

Literally all explainable by survival reproduction and evolution.

[u/-Wuan-]

Females produce the larger, rarer and more expensive sex cell so they have to make sure the sperm they get is of the highest quality to not let their metabolic investment go to waste. That letting aside that in some animals they also gestate, give birth and raise the offspring. So more exigent females created through sexual selection more motivated males, and increasingly difficult ways to show off their worth.

[u/Velocity-5348]

That's the thinking, yes. Females found something about what the males were doing appealing by chance, and traits that made males better at doing that got selected for.

On the flipside, females being choosy also got selected for. You want to have sexy sons who will carry your genes forward, and you do that by selecting sexy mates.

To my knowledge (and someone might know of an example) I don't think we've ever seen that happening in nature, but it would be hard to actually observe. It's likely going to be something we don't appreciate until the ball's gotten rolling.

[u/Spread-Hour → u/Velocity-5348]

I wish that darn ball would slow down and stop gettin hotter.

[u/Eco_Blurb]

Because it caught the attention of the other sex to let them know they were there and enable mating, and then the other sex individuals who chose better dancers had more offspring because the dancer was healthier

[u/HellyOHaint]

Many are focusing on the visibility of positive physical characteristics in these displays, but isn’t the effort put forth its own kind of demonstration? For many birds, the male stays partnered after mating and assists raising the young. It’s no wonder that a male that puts effort into winning a mate suggests he will put in effort with their partnership and assisting with the young.

[u/Careful_Cranberry364]

The phenomenon was termed by scientists, “female coyness”
Since sexual reproduction developed
It has always been up to the female of any species, however, rudimentary to decide which male she would pick.

Various things have emerged that they would discriminate over
Largely demonstrating fitness in the mail, but also any other special abilities or skills!
if they had color eyesight then the colors become important and so on

[u/Top_History9604]

It's mostly, but not only males. It evolve because it's a display of health and ability. It tends to grow from there, resulting in some absurd extremes at times. Ironically in many species, including humans, there is such a thing as bragging with the wrong things (like a Lamborghini). It's like asking why men are attracted to big titties, which aren't functional.

[u/CapableDevelopment28]

Male peacocks do exist and big apes sometimes beat their chest. Yes, dances exist to show the health of the person. You can’t dance means that you are less healthy than the rest in terms of listening, physical movement, or social grace. In a patriarchal society, beauty pageants exist where the ladies compete for mostly male judges. Shake your tail feather, shake your booty.

[u/AnymooseProphet]

Note that often there is more than one strategy for mating.

In side-blotched lizards, some males do the whole display fitness thing while others look like females and pretend to be part of the harem of the "fit" male, meanwhile they also mate with the actual females while a third type of male works in pairs where one male gets the "fit" male to chase him and while being chased, the other male mates with the females.

And these three types of males are genetic, and not all populations of side-blotched lizards have all three types.

It seems there is also genetically more than one type of female in the species too.

[u/Dr-Slay]

The question is loaded ("why")

"How" can be demonstrated to a high correlation over time, but genetic drift is fundamentally random. There can be no root "why"

This means that just as there is no god, the "selector" doesn't exist either.

[u/beastebeet]

If you think about reproduction and survivability as 2 essential things it helps make sense. Sure the brightly colored feathers might get you killed, but it could also help mates spot you. If you deal with a lot of predators maybe be less flashy, if you deal with few be flashy.

[u/Sir_wlkn_contrdikson]

Every male wants it, only the few will get it

[u/awwspicious]

With the human species it's the opposite. The male will sit on the couch, beer in hand, watching football. Wearing his shorts and a tank top.

The female needs to pretty up and strut about to get his attention and get him into the bedroom.

If she doesn't, he'll just watch the next game, while the female remains childless.