Fish come in an astounding array of sizes, shapes, and colors, but only a few can be seen living topside. Of the few species that do emerge from the water from time to time, only the Pacific Leaping Blenny seems truly comfortable on land. Let’s head to the South Pacific for a closer peek at a species that truly is a fish out of water.
A Fish, Yet a Landlubber
Also known as the Leaping Rockskipper, the Pacific Leaping Blenny is a tropical species of combtooth blenny. You’ll find it throughout the southern and western Pacific Ocean, particularly in reef environments in the Marianas, Samoa, Guam, and the Society and Cook Islands. Though you can find these fish underwater at high and low tide, they emerge at midtide to forage for benthic algae, which is their primary food source.
Not only do these peculiar little fish hunt for food while skipping from one limestone rock to another, they also look for mates while above the surface. New research at the University of New South Wales shows that these blennies have actually evolved to the point where they have become poor swimmers and prefer to hide in crevices and rock holes to escape predators. They also blend into the environment very well, as their mottled brown and gold skin blends in perfectly with the hues of the intertidal rocks, so predators like crabs and birds often overlook them.
During the study, scientists looking for the key to the Pacific Leaping Blenny’s survival conducted research to see whether predators would be more likely to attack the fish in sandy, open environments rather than in the intertidal rock environments they prefer. Don’t worry – no fish were harmed during the study! Instead of using real blennies for their experiment, the researchers made detailed life-size models of the blennies from clay. They then secured the models in different places on sandy beach areas where they would stand out, and on rocks where they would blend in. After leaving the models in place for a few days, the scientists returned and collected them.
Not surprisingly, the blenny models that were left on the sandy beach in plain sight showed evidence of multiple attacks by predators. The models that had been hidden in the rocks showed barely any signs of damage, proving that the blennies have managed to survive and make the transition to land by camouflaging themselves among the rocks that also provide them with a steady source of their preferred food.
Experts estimate that animals first began to leave the oceans in favor of dry land approximately 400 million years ago; understanding how they made this transition provides valuable insight into how various species continue to evolve today. Since there are only fossils of early life forms, scientists find species in transition – such as the Pacific Leaping Blenny – extremely valuable for research, as the transitions they are making provide important clues that allow for greater insight into how animals first came to prefer life on land over life in the sea.
Comments
Spectacular