Anonymous at Mon, 22 Jul 2024 01:02:29 UTC No. 16291696

Most people don't even have complete circle of Willis.

Anonymous at Mon, 22 Jul 2024 02:01:52 UTC No. 16291723

if atherosclerosis - anastomosis = bad news brain
if atherosclerosis + anastomosis = collateral supply happy brain

Anonymous at Mon, 22 Jul 2024 02:20:59 UTC No. 16291730

>>16291723
Not a risk factor for people of reproductive age = no evolutionary presence.

Anonymous at Mon, 22 Jul 2024 06:59:54 UTC No. 16291861

>>16291730
true, it might have other unclear functions, or maybe it just randomly emerged and it lingered on because it is also not a hinderance.
But being that it's present in reptiles, birds, and mammals, it probably does something important that we're not quite enlightened about yet.

Thanks for posting this, I was not aware of it.

Anonymous at Mon, 22 Jul 2024 07:00:21 UTC No. 16291862

>>16291730
do you seriously think organisms stop having an impact on their environment the moment they finish reproducing?

Anonymous at Mon, 22 Jul 2024 07:44:36 UTC No. 16291884

>>16291861
I suspect it has to do with something embriologic in a very ancient ancestor. I don't know if amphibians have it, this sort of thing is difficult to look for.

It must have something to do with embriology because that's when cardiovascular changes are more radical e.g. fetal circulation.

Anonymous at Mon, 22 Jul 2024 07:47:30 UTC No. 16291885

>>16291862
That has nothing to do with a redundant feature present across classes.

Anonymous at Mon, 22 Jul 2024 08:02:29 UTC No. 16291896

>>16291603
Symmetry is very cheap evolutionary and connecting 2 small scale features like that is also very cheap. The fact that it probably results in better circulation and more even blood supply is more than enough reason for it to exist.

Anonymous at Mon, 22 Jul 2024 08:10:17 UTC No. 16291901

>>16291730
its not only age that causes clots/strokes
it may be injury related in which case there would be very real evolutionary pressure for developing alternate bloodflow route

Anonymous at Mon, 22 Jul 2024 09:10:51 UTC No. 16291926

evolution selects for symmetry (generally advantageous), but also because symmetrical things are easier to encode genetically.

Anonymous at Mon, 22 Jul 2024 12:24:48 UTC No. 16292034

>>16291730
>parents die
>your competitors with live parents help raise your children
>you suffer disadvantage to early-death parents

Anonymous at Mon, 22 Jul 2024 15:42:09 UTC No. 16292237

>>16291926
>>16291896
You dont know what you're talking about. This is a system that connects the dorsal and ventral circulation, it connects it in such an irrelevant way at best it works as a pressure dissipation system and at worst it only helps the animal well past the age it gets eaten. It may have better benefit in quadrupedals, or like I say it may have to do with some vestigial function during birth, hatching or anything like that.

Anonymous at Mon, 22 Jul 2024 15:54:21 UTC No. 16292244

>>16292237
I fail to see your point, pressure regulation in the most sensitive organ of the body is extremely important and the whole system is free since blood vessels already have an inbuilt tendency to connect to other blood vessels.

Anonymous at Mon, 22 Jul 2024 16:02:06 UTC No. 16292260

>>16292244
>I fail to see your point
It's not indispensable. Not all people have the full circuit, those who don't have it live way past reproductive age. It's found across all amniotes for what I know so far. It's not that it's cheap, it's that it was essential for survival at some point, not merely helpful.

>"le tendency to connect to other blood vessels"
That's bullshit and you know it. Don't know why you people love to talk out of your ass.

Anonymous at Mon, 22 Jul 2024 16:19:36 UTC No. 16292273

>>16292260
>It's not indispensable. Not all people have the full circuit,
Which again blows you out.

>it's that it was essential for survival at some point, not merely helpful.
Contradicted by the previous point

>That's bullshit and you know it
Ok you were baiting, carry on then.

Anonymous at Mon, 22 Jul 2024 16:38:01 UTC No. 16292299

>>16292273
I seriously don't know why people like you love to talk out of their asses when it's clear you have no idea what you're talking about. You got mad and started to make satirical replies. Why? What's your reward in that? You didn't help the thread at all. Is this behavior equivalent to marking territory by smearing shit in walls?