Europe's only cave vertebrate is blind, ghost-white and can outlive a human. It fasts for up to a decade, barely moves for years, and 17th-century locals swore its kind were baby dragons washed out of the rocks.
A pale, eyeless amphibian of the Dinaric karst that hunts by electro- and chemoreception in total darkness — the only cave-adapted vertebrate in Europe.
A tour of everything that makes the olm improbable: the century-long lifespan, the years-long fasts, and a metabolism that looks ordinary for no obvious reason.
When researchers tracked wild olms individually, one barely shifted position for seven straight years. Doing almost nothing may be the secret to living so long.
The study that put the olm's average adult life at 68 years and its maximum past 100 — figures its unremarkable biology still can't explain.
In 2016, cameras in Postojna Cave filmed olm eggs hatching for the first time — a creature that lays only every dozen years or so.
Close-up footage of the animal moving through flooded cave passages, with the feathery red gills and translucent skin that earned it the 'human fish' name.
The folklore behind the 'baby dragon' name dates to 1689, when floods flushed pale, limbed creatures out of the Slovenian karst and into local legend.