11 fish species are capable of walkingChristian Fernsby ▼ | September 10, 2020
An international team of scientists has identified at least 11 species of fish suspected to have land walking abilities.
Species Hillstream loach
Pinpointing which species of hillstream loaches have walking capabilities can help scientists piece together how the first land-walking vertebrates might have come to be.
In a new study, researchers from the Florida Museum of Natural History, the New Jersey Institute of Technology, Louisiana State University and Maejo University in Thailand analyzed the bone structure of nearly 30 hillstream loach species, describing for the first time three categories of pelvic shapes.
Based on the shape of the bone that connects some loaches' spines to their pelvic fins, the team found that 10 other species of loach shared the cave angel fish's unusually hefty pelvic girdle.
Though more than 100 species of hillstream loach are found throughout Southeast Asia, the cave angel fish is the only one whose walking capabilities have been observed and studied.
The team used CT scanning and DNA analysis to trace the evolutionary history of the hillstream loach family and found that, rather than evolving from a single origin, a robust pelvic region appeared several times across the hillstream loach family. ■