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The Magazine of the CALIFORNIA ACADEMY OF SCIENCES |
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Life on the Edge Founding Fathers Among the charismatic minifauna, probably none outshines the seahorse. First and foremost, of course, there is its uncanny resemblance to its landbound namesake. What convergent processes could have produced such shapely heads twice? Despite its vertical posture and unusual shape, the seahorse is actually a fish, related to the pipefishes. But it doesn't behave like a fish. It moves slowly, and must wrap its tail around thin reeds or pieces of coral to avoid drifting off in the current. Its eye rotate separately, like those of chameleons. It is faithful to its partner for life. But its most extraordinary behavior becomes evident when it is time to reproduce. The female transfers her eggs to the male's pouch, where they are fertilized, fed, and nurtured. He becomes responsible for incubating the couple's babies. Today, seahorses might be better off if they hadn't drawn such attention to themselves. But to human minds, all these unlikely, unique, and, perhaps, mystical properties must be good for something. As Chiori Santiago writes in "For Want of a Seahorse," they've certainly caught the eye of practitioners of traditional Chinese medicine. Whether or not pulverized seahorse in tea provides any medicinal benefits is untested. It is said to help with asthma, ease the pains of menopause and, of course, improve virility. None of that can be completely discounted. For example, rhino horn, while not able to enhance manliness, has been found to reduce high fevers in combination with certain herbs far more effectively than, say, buffalo horn. Santiago's article does not question the validity of the medical claims, but is concerned about the consequences. Seahorses are caught throughout much of the tropical Pacific and Indian oceans. Some end up in aquariums, others are casually discarded by shrimp trawlers as part of their bycatch, but most are harvested for medicine. As China has become more affluent, the trade has mushroomed. Dried seahorses can weigh as little as one tenth of an ounce each, while the trade in these fish is measured by the ton--over 70 tons in 2001, according to Project Seahorse. If there is a solution that will maintain both the trade and the seahorse it may be up to aquaculturalists to find it. Seahorses are not easy to keep alive in captivity, and attempts at aquaculture in China in the 1950s were unsuccessful. But there are new experiments afoot on the East Coast and the seahorses have their tails crossed. Males have other interesting tricks up their genetic sleeves. While they have a monopoly on the much disparaged Y chromosome--it's short and relatively useless compared to the other 22 human chromosomes--males have by no means surrendered control of the X chromosome. Jerold Lowenstein writes in "Battle of the Xs" that males can have a lot of influence over the characteristics of their offspring's X. And the qualities that Daddy's X wants to pass on can be in direct opposition to the qualities Mommy's X would like baby to inherit. But the male who is attempting to deliver the most spectacular birth is J. Craig Venter, late of Celera Genomics and perhaps the man most responsible for completing the sequencing of the human genome. As you'll read in the interview in this issue, he's currently involved in two other, equally ambitious, projects. One is to sample the world's oceans and analyze the genomes of all the animals, plants, and bacteria that surrender to his buckets. His other, far more controversial endeavor is to create a "designer microbe," a minimal synthetic life form that, unlike the virus he has already manufactured, will be capable of reproduction. That would make him both mother and father to a whole new kingdom. Keith K. Howell is Editor of California Wild. |