Platypus Crackers

One of the problems in working in the mammal department on the fifth floor of the Museum of Comparative Zoology is the whale supports, the great iron turnbuckles that disappear with Melvillean inscrutability into the ceiling and are anchored somewhere high up in the attic. Two floors below, the skeletons of the leviathans are stretched out for the length of the exhibit room in static mimicry of their aquatic postures. The problem with the whale supports, says M. Edith Rutzmoser, who works out of the mammal department as curatorial associate, is that they get in the way when you're trying to move cases of specimens or open the venerable glass cases that are filled with racks of more specimens.

The mammal department itself is a rectangular oasis of light and better air at the rump of the museum, which you only come upon after a confused trip through the intestinal corridors that wrap themselves around the gray floor-to-ceiling cases and racks. The mammal room is also the only place on the fifth floor that you'll find living mammals. Edie Rutzmoser works there, and in the corner there's Charles P. Lyman, curator of Mammalogy, who is talking on the phone and asking someone where he can acquire a pair of canvas duckback hunting trousers. The walls of the office are covered with lithographs of various mammals and on a desk in the center of the office are a huddle of ledgers with Museum of Comparative Zoology on the bindings. If you want to see just how many specimens of a particular species the department has, you first have to look the animal up in a small file. Under Ornithorhynchus Anatinus, there are 31 listings, cross-indexed to the sagging ledgers. That book says that the first specimens of Ornithorhynchus, commonly known as the duck-billed platypus of Australia, were handed over to Alexander Agassiz in 1878 by E. Gerrard Jr. Those first specimens are skeletal parts and they are catalogued, down to the last tibia, in a small hand in black ink under the title Ornithorhynchus Paradoxus.

Until the 20th century, the platypus was scientifically known as Paradoxus because it is such a baffling creature. It lays eggs, has a toothless bill and its feet are webbed. But it also has fur and a diaphragm, the females suckle their young, and the males have foreskins--all of which are characteristic of mammals. The platypus was discovered in Australian backwaters by westerners in 1797, long after aborigines had cultivated a spiritual respect for the creature. When the first specimens were shipped to England, scientists tried to pry off the bill, because they were convinced it was a graft.

Harvard sent an expedition to Australia in 1931-32 and on February 27, 1932, in Dorrigo, New South Wales, the group trapped one fine dark-furred platypus. He--for it is a he, as he has poison spurs on his back legs--now rests in taxidermic peace, beneath the stupor of paradiethylchloride, with 12 of his fellows in the bottom rack of a huge case of monotremes and marsupials on the fifth floor. It is an austerely bolted cabinet, anciently designed to preserve the skins mechanically if not chemically. The skins lie on great wooden beds that slide out with the surging and lachrymatory bouquet of mothballs. The rest of the monotreme family is represented by spiny echidnas, one rack above--also from Australia, of an ant-eating predilection. The larger delegation is of marsupials, creatures that spend a portion of their pre-natal existences in their mothers' pouches. The kangaroos are small and flat and sad-looking, their once-powerful tails somewhat dessicated by this umbrageous and horizontal, decidedly scientific, afterlife.

Rutzmoser says that no one really looks at the platypus skins. After all, she explains, the taxonomy, or classification, of the creature is no longer a mystery, and students are usually more interested in the bones, which are closeted non-hermetically in another end of the room.

All those who are interested in platypuses came to Romer Library, on the first floor of the MCZ, on Monday to hear Peter D. Temple-Smith give a seminar on the animal. Temple-Smith is from Tasmania and before he came to Cornell Medical School as a post-doctoral student, he spent two years trapping platypuses "on a fairly regular basis," to study the male's crural glands, which secrete the poison that it releases through its spurs.

Pamela Cook, a post-doc at Harvard, introduced Temple-Smith to the informal audience of 20 by calling the platypus a zoologist's "favorite animal of all animals," and Temple-Smith himself allowed that the platypus is "weird". Not nearly enough study has been done on the platypus, he said, largely because it is so difficult to keep in captivity. The biggest work on the animal is a troglodytic volume produced forty years ago by Harry Burrell, and it is an elementary natural history of the platypus. Temple-Smith's own work has been done on the streams and backwaters of Australia, with the use of nets set parallel to the banks, where the platypus lives in a long and shallow burrow.

The platypus, says Temple-Smith, is a very "solitary" animal. Each creature maintains its own burrow and forages for the sea-bottom mollusks and crustaceans that are its diet. When the female releases her young from the burrow, they don't, apparently, return but continue alone. Furthermore, the creature is nocturnal.

The platypus has adapted to its environment through a minor evolution of specializations. Its powerful claws allow it to dig its burrow; its thick fur allows it to maintain an aquatic existence; its musculature allows it to scramble over land, paddle through water, and close its eyes while underwater; and its extremely sensitive bill allows it to find food below the surface. Temple-Smith says, "When we were rowing about at night, the sound of the paddles would attract the animals."

Where the poison glands of the male fit into this survival scheme is what Temple-Smith has been looking into. He speculates that the poison is intra-specific, that it is used by one male platypus against another platypus. He conjectures, from examining the bodies of the platypuses he trapped, that the males attack one another more often than they attack females and that the weapon maintains the solitary nature of the animal. Platypuses, he says, probably have territories, and the poison spur could be the defense.

The other way that platypuses might maintain territories, he says, is with the complicated array of scents that the male secretes from the area around his neck. The scents could be used to mark trees or rocks to warn off other platypuses.

The biologists in attendance took an intense interest in Temple-Smith's investigations. Farish A. Jenkins, Jr., professor of Biology and curator of Vertebrate Paleontology, was especially perplexed by the manner in which the platypus walks--on its knuckles, as shown in a film that Temple-Smith had brought with him. "That running around on their knuckles is something else," he said, shaking his head. "That knuckle-walking bothers me," he added. "I don't know why it should do that."

Temple-Smith agreed that if the platypus is compared with its only closest evolutionary relative, the echidna, the gaits don't match. "How do you reconcile these things?" Jenkins, who has studied the echidna's walk, asked. Temple-Smith responded, "When you look at the echidna, you're looking at a very different kettle of fish."

Jenkins keeps an echidna named Frances on the second floor of the new MCZ labs. He has been studying the locomotion of the echidna, which is a Mesozoic mammal. So is the platypus, but before Jenkins makes conclusions about those early mammals, he says he has to determine what makes them living fossils. "The difficulty in using these as analogs for Mesozoic mammals is that on top of their primitive features are a whole range of specialized features related to their aquatic and fossorial [digging] functions," Jenkins says.

Another scientist who turned up for Temple-Smith's session was Charles R. Schaff, curatorial associate of the museum. One of the reasons Schaff was there is that two summers ago, on a 105 degree day in Big Horn County, Montana, Schaff was on an MCZ expedition kicking around a mesa looking for fossils. The group had been turning up dinosaurs, but on that particular morning, Schaff saw a small bone. "I knew at that moment that I had something," he says now. "Once I spotted the teeth, I knew it was a mammal."

The collection of chips and rocks that Schaff brought back has slowly yielded a Mesozoic mammal, and a distinctive feature of the animal is what appears to be a poison spur on the back foot. Schaff says of the spur that he is "groping for something to compare it with." Thus the platypus. Schaff and Jenkins have collaborated on the work, and amid the litter of clay and tools in the lab is at least one Ornithorhynchus Anatinus skeleton, on loan from the dark racks of the fifth floor.

Edie Rutzmoser, the associate curator of the fifth floor, says that it is not likely that any more platypus skeletons or skins will be coming in within the near future. The department is somewhat strapped for money and personnel, she explains. Somewhere, she says, the department also has a few "alcoholics," or pickled specimens, but she is not sure what has become of them. They might have been thrown away, she says. The embargo on more platypuses, she says, is almost guaranteed by the strict laws Australia has against killing the creatures.

The platypus population was severely threatened in the 1920s, Temple-Smith says, when poachers after the furs had hunted them down. Now, he says, streams as small as one meter across yield platypuses. "Even in dams and ponds with no streams feeding into them you find platypus in them," he says. (He avoids the difficult choice between platypuses and platypi by simply saying platypus for the plural.) But Temple-Smith says he does not know how much more work he will do on platypuses; "the field work is not easy to do." In almost all of the cases of people trying to keep the creature in captivity, the platypuses have died. Just why platypuses dig burrows is not known. Just how the platypus finds its food is not understood. People have never even seen the platypus copulate.