The sea horse is a magical animal, which has puzzled   people for thousands of years. In ancient Rome sea horses were believed to be the babies of Neptune's horses. And Neptune was the god of the ocean. Now we know they are not horses at all -- they are a kind of fish. They still seem as magical as ever, especially to divers who have watched them horsing around  in the sea. But today, sea horse populations face an uncertain future. Fishermen are catching too many of them, and their undersea habitats   are being destroyed. At least 20 million sea horses are taken from the ocean each year. More than 95% are used for traditional medicines in Asian countries. The sea horses are usually dried and then made into powder which is used to treat such problems as asthma , throat infections, skin diseases and cuts. How well the medicines work is unclear. Sea horses are also bought and sold in large numbers as pets. Sea horse expert Amanda Vincent warns against buying pet sea horses. "A lot of people treat them as if they're goldfish," she says. But sea horses require very special care and live food. Most captive   sea horses _ diseases and die. Sea horse experts are trying to teach fishermen to become sea horse farmers. Instead of pulling nets of sea horses from the ocean, fishermen could learn to raise them in specially designed saltwater "farms". That way, fishermen would have sea horses to sell, but ocean populations would not be hurt. Vincent and her team have only discovered the 35 different species of sea horses, and they still have plenty of sea horse secrets left to unlock. That is why, Vincent told TFK, protecting future sea horse populations is especially important: "I promise your readers that by the time they grow up to be marine biologists, we'll still have a lot to learn." In the past, Romans thought the sea horse to be   _  .
a kind of horse a kind of fish the god of the ocean one of Neptune's pets