What evolutionary parallel is suggested by the catfish's fin-based movement compared to tetrapods?
It represents a step utilizing existing paired appendages for directional thrust, a potential rehearsal for jointed limbs
The way *Clarias batrachus* employs its pectoral fins for propulsion on land offers scientists a modern glimpse into ancient evolutionary transitions. While the catfish clearly lacks the complex, multi-jointed structures characteristic of true limbs, its method of using existing paired appendages—the pectoral fins—to generate directional force while supporting weight on a solid surface is highly significant. This mechanical utilization can be viewed as a functional precursor or 'rehearsal' for the development of the true jointed limbs that eventually defined tetrapods. This concept highlights that the fundamental neurological programming and coordination required to move a segmented body using paired appendages were established within the aquatic lineage long before the first amphibians fully colonized land.
