Despite what you’ve been led to believe, planet Earth is practically unchartered territory. About 71% of its surface is covered in water too deep and dangerous to explore. Even on land, unexplained mysteries creep up on all sides, beneath ceilings of dangling stalactites. Caves - and the creatures that live in them - are unlike anything you've probably ever seen before. If anything, they’re more akin to space aliens and the monsters drawn up by authors of science fiction.
Creatures that only live in caves are known as troglobites or troglophiles. Troglobites are obligatory cave dwellers who cannot survive outside of this natural habitat. On the other hand, troglophiles can survive outside of these caverns, but they choose to remain within their confines for the vast majority of their lives. Crazy cave creatures are of two varieties, troglofauna (animals of the land) and stygofauna (inhabitants of the sea).
Here are some mindboggling troglobite facts that prove, once and for all, that a strange, inexplicable universe is footsteps away as opposed to light years ahead.
This cave dwelling critter is blind as a bat, but he’s actually a spider. One of the strangest aspects of his anatomy is that the Kauaʻi Cave wolf spider is the only member of the big eyed spider species who doesn’t have eyes at all. Classified as a troglofauna troglobite, or land dwelling, cave-only creature, this astounding endangered spider is so rare that only three populations of its kind are known to be in existence. Conservation efforts are becoming a pivotal factor in securing this particular spider’s place on the planet. You can find the Kauaʻi Cave wolf spider scurrying through the Koloa-Poipu cave system, hunting down its favorite prey, the Kaua‘i cave amphipod, a tiny crustacean that is, unfortunately, also endangered.
This mesmerizing spider is quite distinguished in its looks. In addition to having a vacant space where eyes should be, it’s also semi transparent and earth toned with silver haired, spindly legs. In addition to population and appearance, the Kaua‘i is unique in that it lacks the characteristic most associated with spiders to begin with. It doesn’t take the time to spin a web. In order to devour prey, this eyeless, webless spider relies on its three vampire-esque, puncturing fangs and its fast, nimble legs, hunting, capturing, and consuming all in one exaggerated movement.
Of all the wonders that caves and caverns hold, who knew they would be guarded by their very own species of snake? This is certainly true of the caves in Thailand and along the Peninsular Malaysia. Cave dwelling rat snakes are a subspecies of the land dwelling beauty rat snake and they possess a similar vicious temperament. The cave dwelling variety survives on regular meals consisting of cave dwelling bats. In one particularly batty cave, these snakes that can grow four to eight feet long upon adulthood, are literally seen dangling from the ceiling on the hunt for fresh flying prey.
Phreatichthys andruzzii are an amazing example of a highly adapted subterranean species. Found in the deep sea caves of Somalia, these non-pigmented ray finned fish are entirely blind and suspected to have been dwelling in cave environments for more than 2 million years. They fall under the classification of stygofauna troglobites, or obligate nautical cave dwellers. They survive by consuming fallen sea insects and other aquatic debris.
This small, silvery species has been the subject of study and controversy for many different reasons. Firstly, it is the one and only animal to be discovered on earth whose biological clock does not rely on the light of the sun to function. Secondly, since it appears to have survived for millions of years without the presence of sight, its numerical acuity - or the ability to process numbers and time - has been studied by scientists. Why? Because these fish can differentiate numbers and time without being able to see.
The olm is a true aquatic troglobite with characteristics distinct to its cave dwelling lifestyle. While it might resemble a translucent snake, or even a body snatching space creature, this odd-looking animal is actually a salamander. It spends its entire life underwater, which is unique to other salamanders found outside of the cave system.
The olm is technically blind, but its sensory system does come complete with photoreceptors that allow it to retain light sensitivity, a component several cave creatures lack, most notably the Phreatichthys andruzzii. The olm is also equipped with taste buds that can detect toxic chemicals, a lateral line that supports up to 15,000 Hz of underwater hearing, and a previously unknown organ on the crown of its head that scientists are now referring to as the ampullary organ. This salamander also has some sort of perception of the Earth’s magnetic field.