Tag: anatomy

andmaybegayer:

vintar:

vassraptor:

vintar:

i’m reading a book on spider biology and here’s some things i’ve learnt so far

  • they can’t move their eyes so when they need to focus on something they move their retinas independently of the rest of the eye instead and i can’t precisely pinpoint why this creeps me out but it does
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  • i mean just look at that
  • they have two main eyes and the rest are secondary
  • which deeply upsets me because there’s quite a few six-eyed spiders and this wasn’t weird when it was just going from a larger number to an arbitrary smaller number, but knowing that they’ve got six because they decided to jettison their main eyes and run on backups is much much weirder
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  • wolf spiders have the best goofy little monster faces. this isn’t

    strictly

    a biology fact but it’s still true

  • big spiders have 30-40 heartbeats per minute and lil dudes can have up to 100
  • their arteries run from the heart, into the chest, and down their legs, and then they open up and dump their blood in their feet. just right in there. let it slosh around. that’s all you need from a circulatory system, right.
  • their blood sloshes around and eventually winds up at the lowest point of their bodies, where their lungs slurp up all that loose blood and shove it back into the heart
  • instead of being made in bone marrow or anything, their blood cells just bud directly off of the heart muscle into the bloodstream
  • they can taste with their feet but not their mouths
  • god spiders are weird

thanks to this post i just looked up spider anatomy on wikipedia (actually i did a search for “spider organs” on duckduckgo and that’s what came up first) and it was even weirder than i imagined, their heart looks like WHAT? and did i misunderstand the diagram or do they have intestines running down all their legs? anyway a+++ would recommend

i get the gist that if there’s something that makes you go “that can’t be right” wrt spiders, it absolutely is right

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mgd is midgut branches and lmao yep they poke down into the leg segments sometimes (or, as in friend jumping spider in fig b, up surrounding the eyes…….)

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their hearts are just tubes! big tubes! so big that you can see them from the outside!!

there’s so much happening inside spiders, who authorised this

Most arthropods have /hilarious/ circulatory systems because a significant chunk of it is “toss the organs in a pool of oxygen enriched blood and hope that works out”