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Zebras’ stripes discourage biting flies from landing

theatlantic.com

11–20 of 54 posts

Re: Zebras’ stripes discourage biting flies from landing

#11
If the theory of evolution is correct, then there is no why to any animal trait. There's no "reason" for the traits, it only happens that maybe some traits allowed the species to survive longer and so they are still around today, but that doesn't mean "someone" enforced a certain trait with a certain purpose.

So, a more scientifically oriented title should be: What do Stripes do for Zebras? Shoo away flies.

Re: Zebras’ stripes discourage biting flies from landing

#12
Interesting theory. Also surprising that the counter-measure to disease-carrying flies is not a stronger immune system but something that gets them fewer bites.

EDIT: but thinking about it more, nothing says multiple traits can't gain traction as a consequence of deadly pressure. I guess I never thought that much about evolution!

Re: Zebras’ stripes discourage biting flies from landing

#14
post #5
post #3

Earlier quoted context omitted.

No, its pretty obvious to recognize a zebra using a neural net (e.g. resnet)

I meant with regards for reference for landings, although I imagine a drone could look around, it’s far larger than a fly.

I've wondered if you could do something similar for keeping birds from landing on flat elevated surfaces. I wasn't thinking stripes though, more like reflective holographic surfaces so the birds couldn't even identify the flat surface as flat. I'm inclined to believe that the crows would figure it out sooner or later though.

Re: Zebras’ stripes discourage biting flies from landing

#17

If the theory of evolution is correct, then there is no why to any animal trait. There's no "reason" for the traits, it only happens that maybe some traits allowed the species to survive longer and so they are still around today, but that doesn't mean "someone" enforced a certain trait with a certain purpose. So, a more scientifically oriented title should be: What do Stripes do for Zebras? Shoo away flies.

No, that's a common mistake. In fact, there can be causation without a sentient causal entity.

Zebras have stripes because their stripes shoo away flies, which helped previous generations of zebras who had stripes thrive and pass their genes forward. Why do zebras have stripes? Because they shoo flies away and evolution ensured that that helpful trait kept passing through descendants until every zebra had it as a dominant, visible trait.

No one ever said there had to be "someone" somewhere to paint zebras black and white, that's just you using anthropomorphized evolution as a straw man/entity.

Re: Zebras’ stripes discourage biting flies from landing

#18
post #17

If the theory of evolution is correct, then there is no why to any animal trait. There's no "reason" for the traits, it only happens that maybe some traits allowed the species to survive longer and so they are still around today, but that doesn't mean "someone" enforced a certain trait with a certain purpose. So, a more scientifically oriented title should be: What do Stripes do for Zebras? Shoo away flies.

No, that's a common mistake. In fact, there can be causation without a sentient causal entity. Zebras have stripes because their stripes shoo away flies, which helped previous generations of zebras who had stripes thrive and pass their genes forward. Why do zebras have stripes? Because they shoo flies away and evolution ensured that that helpful trait kept passing through descendants until every zebra had it as a dom…

It's still a philosophical debate if such an phenomenon can be seen as cause and effect. It's a similar problem as with teleological views in eg biology and medicine: "what's the task/purpose of the lungs?" - there is no predefined task.

Re: Zebras’ stripes discourage biting flies from landing

#19

If the theory of evolution is correct, then there is no why to any animal trait. There's no "reason" for the traits, it only happens that maybe some traits allowed the species to survive longer and so they are still around today, but that doesn't mean "someone" enforced a certain trait with a certain purpose. So, a more scientifically oriented title should be: What do Stripes do for Zebras? Shoo away flies.

While it only happens that some traits allowed the species to survive longer (or multiply more), there's still the "reason why" - there's generally a specific mechanism (or multiple mechanisms) how exactly that trait allows the species to survive longer or multiply more. As that particular mechanism is the reason for that trait being useful, it's also the reason (cause) for that trait to having outcompeted other traits.

So, there's nothing wrong with the title of "Why do Zebras have stripes [other than the obvious default non-answer 'because stripes are somehow good for them']? To Shoo Away Flies."

I.e. "why do they have Y" is "why" in the sense "what's the reason/cause of Y's continued existence".

Re: Zebras’ stripes discourage biting flies from landing

#20
Evolution doesn’t answer to a single why question. Maybe the stripes have been useful to the zebra population’s survival, maybe not – but it is quite clear.that there is no singular reason but a bundle of things. E.g. the stripes make zebras harder to distinguish in a herd, which certainly lead to some percentage of survival. Flies too? Cool! But answering it as if there was some intention behind it? That is not how evolution works.

Evolution doesn’t care and has no sense of meaning, like in genetic algrotihms it is just about which patterns survive, which die and which remain as a funny annecdote with no practical effect.

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