A blind fish capable of “walking” on land could lead researchers to answer many questions regarding the evolution of life on Earth as well as how marine creatures started developing ways to reach out from the sea. Researchers at the New Jersey Institute of Technology have found the cavefish from Thailand to have anatomical features linking mammals and amphibians able to walk on four legs.

The cavefish was identified in Thailand and recorded footage shows the fish walking against a water stream and even climbing waterfalls. The cavefish’s tetrapod-like features resemble the very first land walkers’ attempts to reach out towards the ground. Even though other fish species have developed a similar trait that allows them to move simulating a stable pace, researchers claim the little climber fish shows unique features.

Blind Cavefish
A blind cavefish can lead researchers to answer many questions regarding the evolution of life on Earth. Credit: The Verge

The research involving the study of the cavefish’s unique traits was reported on Friday, March 24, in the journal Nature Scientific Report. Researchers have studied the blind cavefish from Thailand, known as Cryptotora thamicola in order to better understand how former water-dwellers developed into species able to walk on land.

The study from the New Jersey Institute of Technology has provided researchers with plenty of information for them to determine how evolution took place in the development of land-walking skills by former marine creatures. The Cryptotora thamicola cavefish shows a unique feature as the fish has a complete set of pelvic bones attached to its spine.

This separates the waterfall-climbing fish from the rest of the 30,000 fish species across the world. The characteristics found in the Cryptotora cavefish is common in current land vertebrates as well as in ancient tetrapods, thanks to the unveiling of earth fossils. Researchers now claim that further studies involving the cavefish could hold the key to understanding the species evolution from over 420 million years ago, until now.

Exceptional attributes

Co-author of the study Brooke Flammang, claims that the Cryptotora species has an exceptional morphological feature that differentiates the cavefish from any other fish species known in the world. So it’s safe to assume that researchers have struck gold with the finding and further study of the waterfall-climbing fish.

The cavefish’s pelvis and vertebral column allow it to support its own body weight as well as it provides large sites for muscle attachment for walking, according to Flammang. Considering the species known as Cryptotora thamicola is not actually a newly discovered type of fish, further analysis on other animals could provide amazing data for improving researchers’ insight on evolution.

Given that the cavefish will be able to shed light on how sea creatures made their transition to land, the research won’t stop there as new technologic methods to study animals become available.

CT scanners made the examination of the cavefish more practical as it allows researchers to safely get a better understanding of the anatomy of the animal. According to Flammang, a CT scan is way better than taking a photograph of a specimen at a museum.

“This research gives us insight into the plasticity of the fish body plan and the convergent morphological features that were seen in the evolution of tetrapods,” said Brooke Flammang, co-author of the study at the New Jersey Institute of Technology.

Source: Wired