Nature and Fauna
Darkness, moisture and the cold constitute extreme living conditions, however, there are quite a few animal species that have successfully adapted to them.
Postojna Cave is considered to be the richest of its kind in the world both in terms of biotic diversity and the number of cave-dwelling animal species found for the first time; hence, it is often referred to as the cradle of a special branch of biology – speleobiology.
The Dragons' Offspring
The olm has always excited people's imagination. People used to believe that olms were the dragons' offspring, and as a matter of fact this description might not be so far off. The olm is the only European vertebrate living exclusively in the subterranean world.
Although scientists used to believe - for quite some time - that life without the sun or the seasons was not possible, some animal species that inhabit the underground world of Postojna have proven them wrong. By far the best known Postojna Cave inhabitant is without doubt the olm (Proteus anguinus), it is however far from being the only one.
Due to their specific living conditions, cave-dwelling animals evolved in their own unique ways, which includes loss of pigmentation, undeveloped or partially developed eyes, but also acutely developed tactile and olfactory organs. Many specimens have very long tentacles, eyelids and limbs, allowing them to maximize the area they are able to get a sense of.
Cave-dwelling animals are highly sensitive to light, as a result of which their living space within the Vivarium has been suitably darkened.
You can visit the Vivarium daily throughout the year
During the summer months, it is open most of the day, while during the darker months its opening times are somewhat limited.
Over 3,000 Species of Colourful Butterflies
The Vivarium Proteus hall houses a photographic exhibition Butterflies of the World, and a collection of over 3,000 colourful diurnal and nocturnal butterflies from all over the world.