| The Magazine of the CALIFORNIA ACADEMY OF SCIENCES |
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Life on the edge Passive Aggressors Although there are few signs of out-and-out aggression, much of this issue seems to conjure up violence. There's William Light's account ("Eye of Newt...") of the mysterious toxin, tetrodotoxin (TTX), found in a wide variety of species. It's especially prevalent in the ocean, but some amphibians are apt to become carriers as well. While the toxin is generally lethal, these host species have each independently evolved an immunity. Few of the duly armed species are known to use the potion they carry aggressively, but woe betide any predator that takes a bite. Among the carriers is the pufferfish, sought after in Japan as a very expensive delicacy, because a mild dose of the poison creates a certain euphoria. It is expensive in lives, too. A few succumb each year to this Japanese roulette. And anyone who becomes sick enough to require medical attention has only about a 50/50 chance of surviving. There is also evidence that TTX is served up by voodoo exponents, whose victims can become paralyzed, entering a hibernation state where pulse and breathing are no longer detectable. Taken for dead, they are buried, later to be exhumed and, still confused and in shock, enslaved by their new masters. Carnivorous plants are also adept at passive aggression. Nonetheless, the acid and enzyme cocktails that are served up in the depths of some pitcher plants, though evolved to trap insects, have been known to even snare rats. Peter D'Amato, who wrote the introduction and captions to "Come Into My Parlor," has been growing carnivorous plants for over 30 years, and now runs a nursery in Forestville, California, which has the world's largest collection of flesh-eating plants. Jonathan Chester, who first photographed insectivorous plants on the slopes of Mount Kinabalu in Malaysia, later fell under the spell of d'Amato's enthusiasm and now spends much of his time "trying to capture drama in miniature." Another aggressor featured in these pages can only be called passive in a geographical sense. Feral cats do not choose where they live. They are the waifs of a throwaway culture. Many are drawn to large urban parks, or are dropped off there in misguided acts of compassion. As feral cat numbers have grown, bird populations, particularly the ground-nesters, have been devastated. Almost gone from San Francisco's Golden Gate Park are the once plentiful quail and white-crowned sparrow. In "Habitats," Gordy Slack describes the animosity between Sylvester's friends and Tweetybird's. Sylvester's friends come faithfully each day with sustenance and support. Friends of Tweetybird, who think that a wild bird population dependent upon people is an anathema, can only cry "foul!" But, as Jerold Lowenstein points out in "Counterpoints in Science," it is cats, along with chickens, corn, rats, raccoons, and their parasites who are doing just fine, and, as the human population burgeons, are likely to do much better. In acknowledging that it is improbable people will ever change their spots, Lowenstein envisages which animals and plants we are going to be sharing the Earth with a thousand years from now. It will only be those for whom humans are non-toxic. Songbirds, along with most other wild species, won't make the cut. Niles Eldredge, co-parent of the concept of punctuated equilibrium, looks still further ahead. In an interview with California Wild's editors, he explains his theory that species can evolve, and diversity can recover, only when the vector causing the extinction has ceased. In this on-going extinction event, that vector is, Lowenstein's word, "humagen." Keith Howell is Editor of California Wild. |
Summer 1998
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