StoryImage( ‘/Images/Story//Auto-img-114910064923611.jpg’, ‘Photo by Dr. Robert A. Hedeen’, ‘A giant tortoise seems to be content to live in the captivity of a zoo.’);
In 1835, Charles Darwins ship, the HMS Beagle on its five-year trip around the world, anchored in the Galapagos Islands for a stay of several weeks. This gave the Beagles naturalist, Darwin, the opportunity to study the unique flora and fauna of these 15 isolated islands located some 500 miles west of South America, approximately on the equator. Darwin was astonished by the diversity of the species he encountered that were obviously closely related, and this cemented in his mind his basic hypothesis of how new species were formed. Though he studied most of the native animals and plants in detail, it was a group of finches, marine lizards and the giant tortoises that supplied most of the answers to the questions he had asked of himself.
He encountered many animals that were not known to exist anywhere else in the world, but none of these fascinated him more than the giant tortoises that inhabited the various islands. When mature, these colossal reptiles may weigh up to 700 pounds and are generally accepted as being the longest lived of all vertebrate animals. Tortoises of a known age have approached 200 years and may, in fact, reach the ripe old age of 250 years. This means that perhaps some of the tortoises living today were teen-agers when Abraham Lincoln was born.
Legend has it the first humans to see these animals were the Inca Emperor Tupan-Yupanqui and his followers long before the Spanish conquest. The official date of the discovery of the Galapagos, however, is 1535, when the ship of the Bishop of Panama, on a voyage to Peru, was becalmed and put in at the islands that were not on any known map.
Darwin discovered the tortoises abounded on all 15 of the islands of the archipelago, but it is not known whether he knew their numbers were being decimated. Whalers, pirates and merchantmen operating in the Pacific routinely made it a practice to stop by the Galapagos to replenish their food supply with tortoise meat. The reptiles were either killed or taken alive aboard ship and stored in the hold. Held in this manner, they required no food or water for months at a time and provided a constant source of fresh meat for the seamen. When they were butchered at last, they had lost none of their fat or delectable flavor.
Large numbers of the tortoises were slaughtered on the spot merely for the oil their metabolism generated, which resembles olive oil in taste. By the beginning of the 20th century, the species was on the verge of extinction. Now, as a result of rigid conservation measures enacted by the country of Ecuador which owns the islands, tortoise numbers have increased but still are far less than in the days before man became acquainted with them.
In captivity, these animals are gentle and easy to maintain. In some zoos around the country that have them on exhibition, children are permitted to ride astride the rough carapace of the slowly-moving reptiles. One giant tortoise expert measured their maximum rate of locomotion and found it to be about 100 yards in an hours time.
Some years ago when I visited the zoo in Philadelphia, the single resident giant tortoise seemed to be quite nervous and agitated. A zoo attendant told me he believed the tortoise was a male and was upset because of a lack of female companionship.
The lovemaking of the male is involved and has been described by the late American herpetologist Raymond Ditmars, as follows: he stalks around the female in a circle, frequently stopping in a position facing the side of her shell. Here he rises up on his stubby legs and batters his shell against hers, repeating the operation a dozen or more times. This is supposed to be courting, but the resounding thumps are like blows with a heavy mallet or sledge and look far more ludicrous than romantic.
One would think a distinguished scientist like Ditmars would not stoop to such anthropomorphic drivel. Whatever the mating pattern of the giant tortoise, it works for them as they have been around for a long time.
Some years ago, an entrepreneur concocted a preparation whose base was tortoise oil. It was advertised that the agelessness of the reptiles could be transferred to miladys skin. Unfortunately, the venture was a failure, perhaps because the formulation was not made of oil from the giant Galapagos tortoise.
Dr. Robert Hedeen is a former resident of Marylands eastern shore and resided in the Chicago area from 1960 to 1971. He is a retired professor emeritus of biological sciences in the University of Maryland system. He has published more than 30 scientific papers, has written numerous magazine articles, and is the author of two books on the natural history of the Chesapeake Bay.
From the May 31- June 6, 2006, issue