(CNN) — Postojna Cave, located one hour’s drive southwest of Ljubljana, Slovenia’s capital, is so huge, it has its personal railway.
And but, one of many cave’s foremost sights is one thing on the different finish of the scale spectrum — and fully distinctive to Postojna.
Child dragons!
It’s been recognized to locals for hundreds of years and has the graffiti, dated 1213 to show it. Vacationers started arriving in critical numbers after an inaugural 1818 go to by Franz I of Austria, Europe’s final Holy Roman Emperor. About 35 million have adopted in his wake.
It’s simple to see why. The cave is so huge {that a} small prepare runs for the primary two of its 24 kilometer community of subterranean chambers and tunnels.
The prepare line ends on the large Congress Corridor the place the Milan Symphony Orchestra carried out again in 1930. From there a strolling path goes by way of six geological strata, crosses a bridge over a chasm constructed by Russian prisoners throughout World Warfare I and continues previous underground clifftops and gorges, spaghetti-thin stalactites and flowstone curtains.
Journeying to depths of 115 meters (377 toes), at occasions it takes guests by way of slits only one meter huge.
And but the true adrenaline rush is saved for coming nose to nose with the kooky creatures which can be discovered within the Postojna cave system and nowhere else on Earth.
Blind salamanders
Olms develop as much as 25 centimeters in size.
Courtesy Postojna Cave D. D
Olms, or proteus anguinus in Latin, are blind salamanders, about 25 centimeters lengthy, that by no means develop past their juvenile, watery part.
Locals dubbed them child dragons as a result of they have been washed out of Postojna throughout floods and, as caves are the abode of dragons, absolutely these have been their infants, proper?
These days, guests can encounter them swimming among the many rocks in a purpose-built aquarium deep inside the cave.
“Cute aren’t they?” asks Mateja Rosa, a giant olm fan, who works as Postojna’s advertising and marketing and PR supervisor.
They’re certainly. Virtually toylike in look, they’re additionally typically known as human fish as a result of — regardless of dwelling underwater — they’ve pinkish-white, easy pores and skin as a substitute of scales, and limbs with cartoon-like fingers under their busy crimson gills.
They might be blind, however the olms appear to listen to the method of holiday makers, apparently delicate to vibrations. One even attaches itself to the glass tank close to to the place my face is peering in.
Is it curious? Is it being pleasant?
Not so, in response to Primož Gnezda, a younger, enthusiastic biologist who’s been finding out these creatures for years.
“The olms within the cave tank hear you, get frightened and assume their secure positions,” say Gnezda throughout a tour of the Vivarium, an exhibition area subsequent to the cave that shows extra olms and a slew of different Postojna creatures.
The apparently pleasant olm is understood for its uncommon habits, however wasn’t being gregarious.
“It all the time spreads towards the glass for security,” says Gnezda. “That it appeared subsequent to your face was only a coincidence.”
Desk manners
Guests to Postojna can see olms in an aquarium.
Jure Makovec/AFP/Getty Photographs
In keeping with Rosa, olms can reside to 100 years and might survive lengthy durations with out consuming.
“Seven years for certain,” she says. “For the primary two – three years, no drawback. Afterward they begin to shed weight, cease shifting and easily anticipate prey to move by. Any longer than seven years and a few could die, some could survive, relying on the person’s metabolism.”
After they do discover meals, we will forgive their manners.
“We feed them worms,” says Gnezda. “The worms kind a small ball collectively within the water and the olms come and hoover it up complete like a vacuum cleaner. Generally they eat so violently which you can see worms popping out of their gills together with the water.”
The Vivarium results in the lab the place scientists have a license to maintain 10 olms for analysis. Some huge cash is spent on these creatures.
“Biologists have been researching their DNA,” says Gnezda. “Their genome is sort of a novella. It’s 16 occasions longer than the human one and extra sophisticated.”
“You even have lots of empty areas. We don’t know why they exist. Think about a e book 600 pages lengthy, the place all of the phrases are scrambled and we should reconstruct the story.”
Is there a cause we’re so ?
“Their regeneration energy is wonderful. In the event that they lose a limb, they regrow it. The thought of the analysis is to seek out out the mechanism behind it.”
“To not really develop again your arm or your leg, however possibly to supply a brand new human hand or a leg from your individual cells inside a laboratory after which graft it onto you. That’s, after all, far, far into the longer term.”
Mating dance
The olms can reside as much as 100 years.
Jure Makovec/AFP/Getty Photographs
Provided that the olms are cute, don’t require feeding and they’re going to most likely outlive you, Rosa says that previously they have been typically given as pets to visiting dignitaries.
“Most died,” she provides. “Olms have to be stored at round 13 Celsius (55 F). If the temperature rises rapidly, say from 10C to 15C, it kills them.”
Salamanders begin their lives within the water like olms however then they drop their gills, develop lungs, stroll on land and mature sexually; but olms stay and multiply within the juvenile stage — a organic oddity like their shut relative the axolotl, additionally dubbed the Mexican strolling fish.
Olms also have a mating dance.
“It goes like this,” Gnezda says. “When the feminine is prepared, she’ll come to the male. When he smells her, he’ll begin swimming in entrance of her; she’ll observe him and do just a few circles collectively.
“At one level the male will depart a packet of semen on the ground. She’ll decide it up and retailer it in a pocket inside her. When an egg comes out, it’ll be fertilized by itself.”
And that’s not all.
“You possibly can’t inform whether or not an olm is male or feminine from its DNA. Each female and male have the identical chromosomes. Now we’re attempting to tell apart between sexes by analyzing their blood and checking the hormone ratios. It seems promising however that is nonetheless ongoing analysis.”
Hatching dragons
Biologist Primož Gnezda is amongst scientists finding out the olms.
Jure Makovec/AFP/Getty Photographs
Now to the large announcement.
On January 30, 2016 one feminine began feeling very territorial and attacked the opposite olms in the event that they approached her; to the delight of the researchers, they noticed that she was guarding an egg.
Her companions have been instantly eliminated and her tank was remoted. Infrared cameras revealed that she stored laying eggs for one more eight weeks.
“She finally produced 64 eggs,” Gnezda says. “In nature the mom sticks the eggs on rocks, as there’s no actual predator on the market within the cave.”
“However rather a lot can go flawed whereas the egg is growing and round two thirds of the younger simply die by themselves.”
Precisely 4 months after the primary egg had been laid, the primary child child dragon hatched. It thrust out, fell onto the underside of the aquarium after which swam round precociously.
All in all 21 survived. Intriguingly, they’re born with eyes which they maintain for a number of years till pores and skin grows over them and renders them blind.
And since June 2021 two of these five-year-old olms are actually on show.
As Gnezda reveals throughout a tour of the Vivarium, they’re not Postojna’s solely uncommon occupant.
There are cave crickets that eat their very own limbs if they’ll’t discover any meals; toxic cave millipedes; slenderneck beetles whose wings have atrophied and fused on their stomach; cave shrimps, the olms’ most popular snack; and the compulsory bloodcurdling spider — since there are not any flying bugs contained in the cave, spiders use their silk to weave cocoons reasonably than webs.
Speaking of meals, when the olms have been flushed out to rivers by floods, did they ever wind up on somebody’s dinner plate?
Sure, says Rosa. “Up till the Nineteen Eighties you would discover them bought on the slab within the fish markets in Trieste.”
And?
“They style like bland calamari. Or so I’m informed.”
