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minoanmissOne is psychology, really.
Why is it that I' m grooving along, minding my own business, and my brain says to me, "HEY, REMEMBER THAT PERSON WHO HATES YOU? AND TOLD A BUNCH OF PEOPLE LIES ABOUT YOU? AND THAT FIGHT SIX YEARS AGO?" WHYYYYYYYYYYY brain do you do this to me?
More broadly, why are front legs and back legs so different when many vertebrates use them for much the same things? I mean, many don't -- look at rabbits, or great apes, especially the fully bipedal ones -- but many do. I wonder how the pelvis became the big structural organ it is and why it has no real shoulder equivalent.
Why is it that I' m grooving along, minding my own business, and my brain says to me, "HEY, REMEMBER THAT PERSON WHO HATES YOU? AND TOLD A BUNCH OF PEOPLE LIES ABOUT YOU? AND THAT FIGHT SIX YEARS AGO?" WHYYYYYYYYYYY brain do you do this to me?
More broadly, why are front legs and back legs so different when many vertebrates use them for much the same things? I mean, many don't -- look at rabbits, or great apes, especially the fully bipedal ones -- but many do. I wonder how the pelvis became the big structural organ it is and why it has no real shoulder equivalent.
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Brain why
Date: 2020-09-05 08:13 pm (UTC)I will just leave this here. (I first though just to put the first posting but the reblogs... oh the reblogs had me in stitches!)
Re: Brain why
Date: 2020-09-06 01:16 am (UTC)OMG FOSSIL EATING
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Date: 2020-09-05 09:01 pm (UTC)I don't know, but I really resent being haunted by incidents from elementary school.
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Date: 2020-09-06 01:12 am (UTC)It's so unfair!
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Date: 2020-09-05 09:21 pm (UTC)no subject
Date: 2020-09-05 09:39 pm (UTC)A few guesses for (part of) the answer to question 2:
The pelvis is also protecting a number of organs, and the basic vertebrate anatomy has one head, which needs support, and is either forward of or above the heart (depending on whether the animal is a biped).
Something to do with the fact that the pelvis contains reproductive and other organs, and the shoulder area doesn't.
It's inherited from a distant ancestor, which used its front and rear limbs for different purposes. "It made sense at the time" aren't really satisfying, but sometimes that seems to be the answer.
I just spent a little while poking around, and found that Tiktaalik may not be closely related to the first tetrapods that we're all descended from, but there's a lot of uncertainty there.
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Date: 2020-09-06 01:12 am (UTC)Yeah, evolution has a lot of "it made sense at the time" remnants in it.
I need to look up the evolution of the original pelvis (a quick google gives just human/anthropoid pelvis evolution).
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Date: 2020-09-06 02:20 am (UTC)Shoulders are apparently what happens when you take something meant for swimming with, rejigger it into something for standing on, frob it into something to hang from, and then apply a bunch of tweaks for carrying and throwing.
That paragraph in full applies only to humans, I think, though other primates get most of it.
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Date: 2020-09-06 03:23 am (UTC)Quadrupeds (where the four legs appear to do approximately equal things) are generally ambulating forward. Backward locomotion is generally awkward and slower. So, normally the front legs are setting direction and pulling weight forward, while the back legs are pushing. For speed, the back legs need to push harder (more so if the animal jumps even occasionally), front legs just need to be nimble. The higher the body off the ground, the more the front vs back legs are specialized. Going lower, turtles' four legs seem pretty similar, crabs use their eight ambulating legs in all directions, and snakes use side-to-side pushes with no apparent legs.
However, if you run into a Pushme-Pullyou, all bets are off.
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Date: 2020-09-05 09:52 pm (UTC)If you believe Susan Blackmore (and iirc), it's because our brains are memeplexes whose raison d'etre is spreading other memes, and to do that, we try to be consistent and likeable (people are more likely to copy you if you're internally consistent and likeable), so our brains spend a lot of time trying to tuck the loose ends in of where we've been inconsistent (not as kind/clever/graceful as we think we are) or where we have evidence of people not liking us. But the loose ends keep sproinging out again. (This is my wild paraphrasing, and everything I say should be fact-checked, but I found it an interesting and useful framing.)
Blackmore and Jonathan Haidt (The Happiness Hypothesis) both recommended meditation to help manage this (I keep meaning to meditate), and Haidt also had an exercise that's been proven to help, which involves writing about the incident for 15 minutes -- both to get it out of your system and to learn from it -- did you gain anything from the situation, what would you do differently, etc. I think this is supposed to help your memeplex resolve the perceived contradiction. (Even just thinking about "what did I learn/gain?" has been helpful for me; I find it easy to focus on "people hate me" and what they might be thinking about me, and lose sight of "I learned that I can be brave and eloquent (albeit not perfectly so), if the occasion calls for it.")
Anyway. You framed it as a biology question, so here's my philosophy of mind/psychology answer, since I've been reading in that area this year. I hope that's okay!
Also: *huuuuuuuugs*
Ahhh, that's so interesting! Maybe because evolution isn't finished yet?
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Date: 2020-09-05 11:46 pm (UTC)I have a really hard time believing anyone but the most arrant dismissible jackass could hate you. :) hugs you Thank you for all this information about how minds work.
Evolution doesn't really 'finish' or reach a 'destination' so much as continue proceeding like time oor rivers. Part of my curiosity is actually about the origin of the pelvis, since I've never seeen anything pelvis-like in any of the fish I've cut up. I should probbably go read about amphibians...
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Date: 2020-09-06 01:20 am (UTC)no subject
Date: 2020-09-06 02:17 am (UTC)Also, I have found the 15 minutes thing of great help. Sometimes it involves a lot of self-castigation at the beginning and then recentering, and sometimes it involves more analysis starting right out of the gate. It really just depends where *I* am at the time.
Hauntings
Date: 2020-09-05 10:10 pm (UTC)Welp, time to go fall down a well.
Re: Hauntings
Date: 2020-09-05 11:43 pm (UTC)Oh, I understand why those pop up. It's so I can remember to do better.
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Date: 2020-09-05 10:57 pm (UTC)Ha! This is the #1 reason why I hardly draw animals. What is up with their legs, why do they all bend so weird and so different from one another?? *baffled*
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Date: 2020-09-06 01:03 am (UTC)Oh my GOD yes. I was sparked in these thoughts by drawing the unicorn last month and then I was studying the animals in the vet show I watch and thinking about this.
One of these days my roommates are going to find me on all fours on the floor as I try to figure out how animals Work.
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Date: 2020-09-05 11:38 pm (UTC)no subject
Date: 2020-09-06 12:59 am (UTC)Not really -- it connects to and supports different things. While the pelvis anchors the back legs the rib cage doesn't anchor the front legs, and what does (the shoulder assembly) just doesn't seem analogous to me (though admittedly I only have a Bachelor's).
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Date: 2020-09-06 01:04 am (UTC)Ann O.
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Date: 2020-09-06 01:07 am (UTC)no subject
Date: 2020-09-06 02:49 am (UTC)no subject
Date: 2020-09-10 02:52 am (UTC)no subject
Date: 2020-09-06 01:19 am (UTC)no subject
Date: 2020-09-06 01:58 pm (UTC)no subject
Date: 2020-09-06 03:02 pm (UTC)I thought that was just me! Reading the comments here, it's a relief to find out that my brain isn't quite as broken as I thought.
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Date: 2020-09-06 09:49 pm (UTC)This is one of the nice things about an online diary. Yep, you are totally not alone. :)
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Date: 2020-09-08 04:54 pm (UTC)*Do you mean vertebrates, or mammals? Fish tend to be symmetrical. And birds use their forelimbs to fly, which makes them very asymmetric.
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Date: 2020-09-08 05:12 pm (UTC)I should probably look up the exact clade I want to discuss. I mean "land-living vertebrates who walk on all fours". So not bipeds (not birds, kangarooos, or humans) and not aquatic creatures (such as fish, though looking at sea mammals and turtles might be interesting). I was inspired to this question by contemplating quadrupeds such as cows and lizards and salamanders.
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Date: 2020-09-09 03:29 am (UTC)