Lost world gives up prehistoric flora and fauna

Press, 29 March 1985, Page 26

Lost world gives up prehistoric flora and fauna

By

Edward Holland

of Associated Press (through NZPA) Caracas A remote, cloud-covered mountain in the jungles of southern Venezuela has provided a lost world where plants and animals have evolved in isolation since prehistoric times. Scientists who ended a year-long study on Cerro de la Neblina—the Mountain of Mists — brought back samples of dozens of previously unknown species that will take years to analyse. More than 120 Venezuelan, American and British scientists took part in the expedition, representing almost every speciality in botany and zoology. The specimens they collected range in size from microscopic fungi to snakes six metres long. “In terms of the groups I’ve worked with, almost everything we’ve collected up there is unknown,” Roy McDiarmid, a reptile and amphibian expert with the United States Fish and Wildlife Service, said in an interview. Up there is a 3000 metre mountain tucked into the Venezuela’s with Brazil. Despite its height, La Neblina was’ not discovered until 1953 by two American scientists, Bassett McGuire and John Wordach. La Neblina is one of the Tepuis, the flat-topped mountains scattered throughout southern Venezuela. The mountain is a geological island, the remnant of a huge sandstone

plateau. La Neblina contains a variety of tropical forest habitats of flora and fauna that have developed on their own for millions of years. “As you get isolation, you don’t get any genetic exchange between a lot of these things,” Mr McDiarmid said. Of the 15 species of frogs, snakes and lizards he collected on La Neblina, McDiarmid says, all but three of them are almost assuredly new. Similar discoveries were found by botanists and zoologists in a wide range of specialties. While the geologic age of the Tepuis is estimated between 80 million years and 1.2 billion years, lack of fossils makes it impossible to say how far back La Neblina’s life forms date. Mr McDiarmid says most of the birds, mammals and reptiles are Cenozoic-type things, which means their species could have first appeared as long as 65 million years ago, the geological era when primitive man appeared. Some scientists speculate that in their ancestral forms, the reptiles, amphibians and insects date from the Mesozoic era (between 135 million and 230 million years ago), when dinosaurs stalked the Earth. Half the specimens collected will go to the participating institutions abroad and the other half will remain in Venezuela. Specimens will be compared with those from highland areas on other continents. Similarities could pro-

vide biological support for the continental drift theory, an idea which has already been corroborated by fossil evidence. The theory states that the present continents broke away from what was a much larger land mass under intense geological pressure. Charles Brewer Carias, a Venezuelan explorer and naturalist who co-ordinated the study, said one flowering plant, the pitcamia, a type of bromeliad like the pineapple, has already been found in Africa. The expedition began in January, 1984, when three scientists flew by helicopter to the mountain to set up a base camp in a clearing near the Baria River. Despite rain, bugs, and the cold at higher elevations, working conditions were generally good, Mr McDiarmid says. But the study ran into trouble of a different sort when politicians began asking what foreign scientists were doing in a remote border region of Venezuela, and press reports accused them of spying and taking out gold and strategic minerals. Bureaucratic roadblocks suddenly appeared; some scientists were searched, specimens taken away and at least one expedition member detained. Brewer Carias insists, however, that the Government’s official policy all along was to support the expedition, and that the problems came from individuals in authority acting on the basis of the bad information.