Summary
- The northern sea robin uses its legs as both feet for walking and sensory organs to taste the ocean floor for prey.
- Scientists discovered that the sea robin’s leg prowess evolved over time, repurposing its appendages for sensory capabilities.
- The fish’s sensory legs have taste-receptor molecules specialized in detecting amino acids and chemicals produced by deep-sea organisms.
- A gene called tbx3a was found to play a crucial role in developing legs and sensory organs in the sea robin, as seen through gene-editing experiments.
- Through examining the genomes of various sea robin species, researchers found that legs for walking developed first, followed by the evolution of sensory organs on some species’ legs later.
In a groundbreaking discovery, scientists have found that a unique fish called the northern sea robin has legs that serve dual purposes – walking and tasting the sea floor for buried prey. This fascinating revelation sheds light on the evolutionary history of the sea robin family and how the fish has adapted over time.
Fish with a difference
The northern sea robin, scientifically known as Prionotus carolinus, is unlike any other fish with its bulging eyes, bird-like fins, and six legs resembling those of a crab. Researchers have long known that the sea robin’s legs have special sensory capabilities, allowing it to detect prey hidden under sediment. Molecular biologist Nicholas Bellono notes that the sea robin’s hunting abilities are so efficient that other fish follow them around in hopes of finding food scraps.
New findings
Bellono’s team, in collaboration with developmental biologist David Kingsley, conducted experiments to study the sea robin’s ability to locate and extract buried food using its legs. They discovered that the fish’s legs are covered with taste-receptor molecules specialized in detecting amino acids and chemicals from deep-sea organisms. Interestingly, when the researchers accidentally obtained a different species of sea robin known as P. evolans, they found that this species’ legs lacked the sensory papillae present in P. carolinus, suggesting that legginess and tasting ability evolved independently.
Evolutionary insights
By comparing the genomes of 13 sea robin species from around the world, scientists constructed an evolutionary family tree that revealed the development of legs for walking preceded the evolution of sensory organs on some species’ legs. Further investigation into the genes active in the sea robin’s appendages led researchers to a gene called tbx3a, which plays a crucial role in the development of legs where fins are typically found in other fish. Mutating tbx3a in P. carolinus using the CRISPR-Cas9 gene-editing tool resulted in the loss of sensory papillae and the fish’s ability to locate buried food.
Implications of the research
The discovery of tbx3a’s role in leg development and taste perception opens up new possibilities for genetic research and potential applications in genome editing. By understanding how mutations in tbx3a led to the evolution of sensory legs in sea robins, researchers may be able to replicate similar genetic changes in other fish species. These findings highlight the complex interplay between genetics and evolutionary adaptations in the animal kingdom.
Overall, the research on the northern sea robin sheds light on the fascinating evolution of sensory organs in fish and the role of specific genes in shaping unique traits. The study provides valuable insights into the genetic mechanisms driving evolution and opens up new opportunities for further research in the field of marine biology.
Zoology, Marine Biology, Environmental Science