rat bastard

sequences from my 'moth for halloween' animation

the second part of the death note text posts I just posted.

bogos binted?

fork spotted in kitchen come on now

a silly alternate universe for us dumbass gaijin dandadan viewers

there’s no way someone else in the dandadan fandom hasn’t already drawn this but i had to roll with the vision when it struck me

Yeah that’s how I remember the manga

ダンダダン Ep. 04: Kicking Turbo Granny's ass

was browsing thru papers about animal coloration and learned that a gene that helps make the placenta in humans (the thing that keeps you alive when you're a fetus in the womb) also exists in cheetahs, but in the cheetahs, it just controls the placement of their spots

How does THAT happen?!

this is the paper

cheetahs and domestic cats, with a mutation that breaks this gene develop more chaotic and random patterns on their fur, showing that the gene is important for organizing the pattern of the markings

Noticeably, the cats and cheetahs don't die in the womb from placenta not working. Which means that either the cats turned their make-placenta-do-the-thing gene into a spots-organizing gene, or humans somehow need a spots-organizing gene to Get Born like the biological equivalent of a load-bearing jpeg of a coconut. Or at some point long ago, evolution was like "eh, put make-placenta-do-the-thing and spots-organizing on the same gene, it'll be fine." All of these options are hilarious.

i regret looking at the notes on this post because i am in tears. "my hypothesis is that--" babes please remember how you learned to make a hypothesis back in third grade. you can LOOK UP what the gene is! you don't have to just MAKE UP FACTS to show off how smart you are! PLEASE actually click through links before speculating or just making claims, jfc

the paper OP links is a review on the evolution & genetics of mammilian coat pigmentation by Eizirik and Trindade. Using control+f for "placenta" easily gets you the passage in question:

So basically, Eizirik et al. suggest that in their model for cat coat development, there's some sort of establishment of what the pattern will look like during embryonic skin development, which they call "prepatterning." That "56" citation leads to a paper that found that two genes (Taqpep and Edn3) contributing to tabby pattern variation.

So what is this Taqpep? According to 56 (Kaelin et al), it's "a type II membrane-spanning protein of the M1 aminopeptidase family, whose members are characterized by the presence of GAMEN exopeptidase (SAMEN in Taqpep) and HEXXHX18E zinc-binding motifs in their extracellular domains," which is a ton of jargon that's way outside my area of knowledge. But, long story short: it's a guy that hangs out on membranes and does stuff to proteins. There's lots of different aminopeptidases, but this specific one was previous only found in human embryos (x). given humans and cats have a common ancestor, it's not weird we have some of the same genes. it is always pretty interesting when our same genes seem to do different things!

also, BTW, here's the Kaelin et al proposal for what role Taqpep plays in skin development:

i wanted to see if anyone else was publishing on this, and i found a write up by the same guy as the review (Eizirik) on a study on Taqpep's role in tiger stripes:

so, it appears to me that the link between the human function of Taqpep and the cat function is just something Eizirik is really intrigued by, rather than something the researchers in the cited studies are actually interested.

as several people in the notes have pointed out, it is a common pattern for the same genes to have different functions in different species, simply because they've had millions of years to change and repurpose all sorts of things. Taqpep isn't a magic "make pigments appear" gene and it's not a magic "make a placenta" gene-- it's a tiny membrane protein that slots into how a huge number of different genes work together to make more obvious phenotypes. perhaps cats simply do not need it for placentation, or they have another gene that now serves the same function. maybe millions upon millions of years ago, it did something completely different in the human-cat common ancestor. my point is, we don't know, and none of the publications i've cited speculate because apparently no one has looked into it (or if they have, Eizirik is not citing them and i didn't see them when I looked to see who was citing the pigmentation papers). there's multiple comments in the notes like "oh, it's probably this" based on literally nothing and apparently this is a huge pet peeve of mine!!!! did you know you can click the link and view what the gene is and what it codes for!!!!!!!!!

also people keep bringing up lines of blaschko/the human stripes post, which i also did a write up on because there's a ton of misinfo out there on it

hey i think people guessing and coming up with ideas about things is important to developing scientific thinking.

This is cool information but telling people they're wrong to speculate and think of ideas without researching in depth themselves first does not help them develop their curiosity

my point isn't that you shouldn't be thinking about your own theories and ideas, it's that you (general you) are fully capable of then looking into the information available and seeing if it jives with your ideas or not (or, indeed, if someone hasn't already answered your exact question!). that itself is a crucial part of the scientific process & scientific thinking. that's why i included links and my own thought process for how i looked into the question. i even hunted down open access links where i could find them.

to clarify because my post is worded a little aggressively, i am not annoyed by individual tumblr users, because i understand "oh i just had this thought" is a normal thing to post on a personal blog. however, i'm annoyed by the general trend of random speculation because it sometimes leads to "someone makes a plausible-sounding speculation on biology but DOESN'T disclaim their idea is based on literally just a tumblr post -> it gets spread as fact." it's something i've seen happen over and over on this website, like with the linked "human stripes" post. in this case i think i was extra frustrated because there's literally a link to the review in the post, where you can see the name of the gene in question and what sort of thing it codes for, rather than just make random guesses

It's all good. I get overwhelmed considering how much faster it is to propagate misinformation than correct it. However I have a general optimism with the power of curiosity to help people develop and sharpen their critical thinking skills.

It's like how sometimes before looking up a question on the internet, you ask it to your friends or family to see what they think, and after you have argued about it you can see how your reasoning failed or held.

I post in ways to invite this kind of speculation and thinking, because I really experience a lot of joy and happiness both in finding new ideas and in watching the lights flicker on in people's brains as they consider a new idea

One of the best ways to learn to think and reason, is for other people to model that process of learning. It's like how any animals learn, by imitating others and practicing the steps in play. This is play. We're playing.

So instead of researching everything at the start and posting a detailed explanation of how a complicated process works, I share my initial reaction to learning a new thing (A gene that makes placentas work in humans, controls the arrangement of the cheetah's spots?? How does that happen????) and elaborate upon it and discuss it as I look further into it, and sooner or later other people chime in, elucidating how the complex mechanisms that could be behind this strange thing work, which leads to more discussion and more ideas, and soon everyone has a much greater appreciation for the complexity and weirdness of biology.

Telling people information doesn't model the process of thinking and investigating, and I think that is why so many people lose their curiosity over their life.

You've done a great job here with modeling the process of investigating a perplexing question. I just think it's important to remember that it's playful, it's just practicing the art of being curious, thinking, and researching in a safe, low-stakes environment.

oh no....the full moon...you have to run, i won't be able to control myself once i tr-AUGH....GRRRRRRRAAAAAUUUYGGGGHHHHHH *painfully contorts my body and my bones crack and when my scary transformation is complete i am a little rabbit sitting peacefully on the ground*

kind of embarrassing to play a game that your friend recommended it’s like. ohh i’m pregnant with your game. i’m playing and it’s yours

Your tags have been reviewed @ruffboijuliaburnsides