A waterfall-climbing fish in Hawaii uses the same muscles to both rise and feed, researchers have discovered.
Scientists looked at the Nopoli rock-climbing goby (Sicyopterus stimpsoni), also known in Hawaiian as o’opu nopili. This plant-eating fish is found throughout Hawaii, and was once greatly relished as food, apparently being a favorite snack among priests.
Many gobies can inch their way up waterfalls with the aid of a sucker on their bellies formed from fused pelvic fins. The Nopoli rock-climbing goby, on the other hand, can climb waterfalls as tall as 330 feet (100 meters) with the aid of a second mouth sucker, which develops after their mouthparts move from a forward-facing position to under the body during a two-day-long metamorphosis into adulthood.
“For a human to go the equivalent distance based on body size, it’d be like doing a marathon, some 26 miles (42 kilometers) long, except climbing up a vertical cliff-face against rushing water,” researcher Richard Blob, an evolutionary biomechanist at Clemson University in South Carolina, told LiveScience. Indeed, an old Hawaiian saying is that as the Nopili clings, so will luck.
The goby, which can grow up to 7 inches (18 centimeters) long as an adult, feeds by cyclically sticking the tip of its upper jaw against rock to scrape food off surfaces.
( via news.discovery.com )