Like early creatures that walked out of the sea, a blind cavefish can climb rocks and waterfalls. Researchers from the New Jersey Institute of Technology discovered that the fish in Thailand has a unique feature that allows it to crawl in a way not seen in other fish species.

The researchers believe the rare fish, Cryptotora thamicola, may reveal how critters made the switch from living and swimming in water to walk on terrain. The finding has offered clues showing that the species may have evolved millions of years ago, as per the researchers.

The research team conducted a study to examine the unique feature of the cavefish and found that the Cryptotora thamicola has characteristics similar to tetrapod, a four-footed mammal. The fish was using its fin to walk like the mammal, said the researchers.

The study has been published last week in the journal Scientific Reports.

The fish is extremely rare because it has fin structures unlike any other fish species, said a researcher of the team. “Out of the 30,000 species of fishes that we know to exist, these fish are truly spectacular and look different than everything else that we’ve ever seen”, the researcher paper added.

As per the study, the fish is blind, but still, it is capable of navigating waterways and climb rocks like a salamander. It has evolved with a robust pelvic girdle which makes it walk like a four-legged mammal, the research noted.

When watched from evolutionary perspective, the discovery is huge, and the Cryptotora thamicola is the first fish that must have acted in such a manner, said Brooke Flammang, an assistant professor from Department of Biological Sciences of the New Jersey Institute of Technology.