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Thanks to Siya, Zachary, Khalil, and Eilee for their suggestions this week!\n\nThe enamel pin Kickstarter goes live on Wednesday, August 14, 2024!!\n\nFurther reading:\n\nHow spiders breathe under water: Spider\u2019s diving bell performs like gill extracting oxygen from water\n\nAggressive spiders are quick at making accurate decisions, better at hunting unpredictable preys\n\nInto the Spider-Verse: A young biologist shares her love for eight-legged creatures\n\nA New Genus of Prodidominae Cave Spider from a Paleoburrow and Ferruginous Caves in Brazil\n\nThe diving bell spider [photo from this paper]:\n\n\n\nJumping spiders are incredibly cute, even the ones that eat other spiders [photo taken from this excellent site]:\n\n\n\nThe spoor spider's web looks like a cloven hoofprint in the sand [photo by JMK - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=39988887]:\n\n\n\nShow transcript:\nWelcome to Strange Animals Podcast. I\u2019m your host, Kate Shaw.\nI\u2019m excited this week, because on Wednesday my little Kickstarter to fund getting more enamel pins made goes live, and also we\u2019re talking about some weird and fascinating spiders! Thanks to Siya, Zachary, Khalil, and Eilee for their spider suggestions!\nA lot of people are afraid of spiders, but don\u2019t worry. All the spiders in this episode are small and completely harmless unless you are a bug. Also, they probably live very far away from you. Personally, I think most spiders are cute.\nLet\u2019s start with a spider suggested by Siya, who pointed out that we don\u2019t actually have very many episodes about spiders. Siya suggested we learn about the diving bell spider, a tiny, remarkable animal that lives in parts of Europe and Asia.\nThe diving bell spider gets its name because it mostly lives underwater but still needs to breathe air, so it brings air with it into the water. A diving bell made by humans is a structure shaped sort of like a big bell that can be lowered straight down into the water on a cable. If the diving bell doesn\u2019t tip to one side or another, the air inside it stays inside and allows a human diver to take breaths without coming to the surface. A diving bell made by spiders is made of silk but is shaped sort of the same, with an entrance at the bottom. The spider builds its bell among water plants to anchor it and keep it hidden. The spider brings air from the surface to replenish the supply of air inside the bell.\nThe spider does this by surfacing briefly. Its belly and legs are covered with tiny water-repellent hairs, and after surfacing the hairs trap air, so that when it dives back into the water it\u2019s covered with little silvery bubbles. It swims down to its diving bell and rubs the bubbles off its body, which rise into the bell and are trapped there by the closely woven silk. Then it goes back to the surface for more air.\nOnce the bell is full of air, the spider only needs to replenish the air supply about once a day under normal circumstances. That\u2019s because the bell itself acts as a sort of external gill. It\u2019s able to absorb oxygen from the water quite efficiently, but it still loses volume slowly because nitrogen from the air diffuses into the water. If not for that, the spider probably wouldn\u2019t need to come to the surface at all.\nThe diving bell is the spider\u2019s home, especially for the female. Unlike most spiders, the female diving bell spider is much smaller than the male and she hunts differently. The male is an active hunter, swimming quickly to catch tiny animals like mosquito larvae, so he\u2019s large and strong but only has a small diving bell. The female spends most of her time in her diving bell and only swims out to catch animals that come too close, or occasionally to replenish the air in her bell.\nWhen the spider leaves its diving bell to hunt, air bubbles remain trapped on its abdomen, which allows it to breathe while it\u2019s hunting too. Then it can dart back to its bell to get more air or hide if it needs to.