15 Beyond Fascinating Adaptations Of Cave-Dwelling Creatures

Most of us are more than a little wary of caves, and with good reason. Their dark, dank interiors are concealed from us, giving our minds ample opportunity to imagine all manner of weird looking cave animals creeping and crawling in their depths.

Caves have extremely rare and strange ecosystems, and the animals that live there have adapted to live away from the sun. These bizarre animals living in caves don't look like their brethren on the outside. That's because these cave-dwelling or troglophilic creatures have adapted to their extreme environments in very extreme - and often icky - ways. These scary cave creatures have some bizarre adaptations they've devised to master living in a subterranean world.

Photo: Photo by Greg Hume / Wikimedia Commons / CC-BY-SA 3.0

  • The Tobini Cave Millipede Turned Four Of Its Legs Into Penises

    The Tobini Cave Millipede Turned Four Of Its Legs Into Penises
    Photo: Marek, P.; Shear, W.; Bond, J. (2012) / Wikimedia Commons / CC-BY 3.0

    Illacme tobini was discovered in October 2016 by cave biologist Ben Tobin of the National Park Service, found living deep underground in dark marble caves in Sequoia National Park in California. This creature has some really bizarre adaptations to subterranean life. While its closest relative, the Illacme plenipes, has 750 legs, Illacme tobini only has 414 legs. Additional modifications to cave life include strange mouthparts, four legs that have turned into penises, silk-secreting hairs, and nozzles on every segment that squirt a defensive chemical that is still a mystery.

  • Texas Blind Salamanders Have No Eyes
    Photo: Ryan Hagerty/USFWS / Wikimedia Commons / Public Domain

    The Texas blind salamander is a highly specialized salamander species only found in the water-filled caves of Hays County, TX. The top predators in their niche environments, the Texas blind salamander has adapted to total darkness so well that it no longer has eyes, only two black spots where eyes would normally be. It does not need pigment to protect its skin from sunlight or for camouflage, so its skin is translucent and ghostly white. The US Fish & Wildlife Service has classified them as endangered because of their restricted range and the threat of water pollution.

  • Tailless Whip Scorpions Have Crazy Legs To Move Around Dark, Dank Caves

    The tailless whip scorpion, also known as the cave spider, is neither scorpion nor spider, but its own order of arachnid called Amblypygi. Tailless whip scorpions look terrifying, but they are not venomous and pose no threat to humans. Their bodies have developed to be low to the ground so they can stick closely to cave walls and fit through narrow cracks. They have poor eyesight, but make up for it with highly-modified front legs that grow extremely long and act as feelers to help it hunt for food in the dark subterranean environments they call home. Unlike other arachnids, which are largely solitary and primarily concerned with hunting, tailless whip scorpions have adapted to the lack of space in suitable caves by becoming less aggressive and territorial, allowing colonies of them to live together without cannibalizing each other.

  • Phantom Cave Snails Are Completely White - Unlike Their Non-Cave Relatives

    Phantom cave snails are cave-dwelling relatives of freshwater gastropods known as springsnails, native to a small series of caves in the vicinity of Balmorhea, TX. Like many subterranean creatures, phantom cave snails are blind and have abandoned the use of pigment in their bodies so they appear pale white or transparent. They also have more convex shell whorls than their terrestrial relatives, longer umbilicus, and a simple penis. Due to their existence being dependent upon three small springs, the phantom cave snail is considered to be a critically imperiled species.

  • Grand Canyon Pseudoscorpions Have No Stinging Tail

    Scientists were amazed when two new species of pseudoscorpions - ancient relatives of scorpions that lack tails with venomous stingers - were discovered living in the same caves in the Grand Canyon. It is rare for two related species of predators to co-exist in a single cave system, so scientists think the cave must have a robust ecosystem with ample food. Named Hesperochernes bradybaughii and Tuberochernes cohni, the two species of arachnids have adapted to the lack of a stinging tail by having venomous stingers in their pincers. They retain limited use of their eyes, but have lost much of their bodily pigmentation.

  • The Mexican Blind Cavefish Looks Different Than Its Fish Relatives, But Can Still Reproduce With Them

    The Mexican Blind Cavefish Looks Different Than Its Fish Relatives, But Can Still Reproduce With Them
    Photo: H. Zell / Wikimedia Commons / CC-BY-SA 3.0

    Found in caves throughout Mexico and the southern United States, the Astyanax mexicanus, commonly called the Mexican blind cavefish, can co-exist with and still reproduce with its surface-water relatives, even though it has become heavily mutated and modified from years in total darkness. To conserve energy, Mexican blind cavefish have lost their eyes and the vision center of their brains, as well as their pigmentation; their scales have become translucent. The Mexican blind cavefish have adapted to being blind by having taste buds that grow on the outside of their lower jaws, which help them taste the water around them for food.