Their nearest relatives are sharks, stingrays, devilrays, and skates. They are marked by mystery, a seductive sinuosity, a strangeness hard to penetrate. What look like wings to us are the manta's pectoral fins. But they are strong. If a manta gets entangled in an anchor line, it can pull a boat for miles.
Most rays live sliding along the sandy ocean floor, digging up mollusks.
The fins on their heads have evolved to form flexible scoops around their enormous mouths, and they feed by swimming placidly with mouths wide open, sending great quantities of water through sets of branchial filters that collect the miniature sea life. They usually die in captivity, refusing to eat and seeming to experience tremendous stress when confined. Three mature mantas in an aquarium in Okinawa, Japan, are the only ones known to have survived any time in a tank-and those three are in a really big tank. The Makai reaches the dive site, just south of downtown Kona, in full darkness, not far from the shoreline and a line of hotel lights. These days, thousands of divers and snorkelers come to this one bit of coastline every year.