With the olm’s sinuous body and external gills, it\u2019s not too difficult to understand this particular case of mistaken identity.\u00a0<\/p> Olms are about a foot long (12 inches or 30cm) and are one of the weirdest animals in the world<\/a><\/p> Unlike the majority of amphibians<\/a>, the olm is completely aquatic, and like all troglobites (true cave-dwelling creatures), it is adapted to living its whole life in the darkness of caves. It lacks any pigmentation in its skin, resulting in it being a pink or yellow-white colour. This led to it being described as a \u2018human fish\u2019 by locals, due to the similarity of its coloration to their own skin colour.\u00a0<\/p> Skin pigmentation isn\u2019t the only thing the olm lacks. Its eyes are severely undeveloped and, in fact, after a few months of development during its larval stage, its eyes begin to atrophy (wither away). It does retain a small amount of photosensitivity, but why bother growing eyes at all if they aren\u2019t going to be used for subterranean hunting? Instead, priority is given to its other senses.\u00a0<\/p> ” Olms are cave-dwelling salamanders that have been surrounded by mystery for centuries.”<\/p><\/blockquote> The olm has enhanced mechanosensory and chemosensory abilities. \u201cHearing is essentially mechanosensory \u2013 picking up vibrations or sounds caused by the motion of prey,\u201d says Professor Geoff Boxshall, a zoologist at the Natural History Museum<\/a> in London. \u201cSimilarly, for chemosensory abilities \u2013 it would be important for a scavenger locating decaying bodies, as there would be a good source of chemicals diffusing out of them, and the scavenger could home in on that.\u201d\u00a0<\/p> However, the olm also has an extra sense \u2013 the remarkable ability to sense the bioelectric field of other organisms. \u201cAll animals produce a weak bioelectric field from nerve impulses, muscle contractions, and so on,\u201d continues Boxshall. \u201cThe olm is able to sense when its own bioelectric field is disturbed by an interaction with the field of an approaching creature, such as a shrimp, and can then catch its prey.\u201d\u00a0<\/p> Caves are low-energy systems, with no light and thus no plants nor photosynthesis<\/a>. Cave food-webs are reliant on nutrients flowing into the cave from outside. The unreliability of such systems means that patience is the key for a cave\u2019s residents.\u00a0<\/p> The olm is an ambush predator, lurking silently and completely still, waiting for some unknowing creature to enter its bioelectric field. <\/p> During times of plenty, the olm is able to consume considerable amounts of prey and lay down reserves in its liver, to tide it over when food is scarce. Research has shown that, in extreme cases, olms can survive for a decade without feeding. If food is scarce, an olm will reduce its activity and lower its metabolic rate. In severe cases, it can even reabsorb its own tissue for nutrients.\u00a0<\/p> “The olm is an ambush predator, lurking silently and completely still, waiting for some unknowing creature to enter its bioelectric field.”<\/p><\/blockquote> The olm develops relatively slowly and scientists don\u2019t actually know how long it lives. One captive olm was recorded as being at least 58 years old, but there are some estimates that olms could live to be 100 \u2013 there’s still much to be discovered about this elusive species.\u00a0<\/p> The olm is renowned for being a pale creature lacking skin pigmentation. However, not all olms are the same. In fact, there is one recognised subspecies, Proteus anguinus parkelj<\/em>, the black olm, which can be dark brown as well as black. Discovered in 1986, the black olm is restricted to an area smaller than 100sq km near Crnomelj in Slovenia.\u00a0<\/p> As well as having pigmentation, the black olm has a number of other differences to the nominate subspecies (P. a. anguinus<\/em>). Its head is slightly shorter, with strong jaw muscles, and it has shorter legs. Though its body length is slightly longer (it has 34\u201335 vertebrae compared to 29\u201332 in the nominate subspecies), its tail is shorter, in proportion.\u00a0<\/p> In addition, rather than having completely regressed eyes, the eyes of the black olm develop almost normally, and have principal rods, and both red-sensitive and blue-sensitive cones.<\/p>How big are olms?<\/h2>
What do olms look like?<\/h2>
Do olms have eyes?<\/h2>
How do olms find their prey if they are blind?<\/h2>
![\"Olm](\"https:\/\/c02.purpledshub.com\/uploads\/sites\/62\/2024\/02\/Olm-1.jpg\")
What do olms eat?<\/h2>
How long do olms live?<\/h2>
What is a black olm?<\/h2>