VOA常速英语2008年-Ancient Population of Little People Found on Pa(在线收听

By Delia Robertson
Johannesburg
12 March 2008

Scientists from a South African university have found evidence of a population of what they say were small-bodied modern humans on an island of Palau, east of the Philippines. VOA's Delia Robertson reports from our bureau in Johannesburg the find appears to support the argument that bones of so-called Hobbits, found on an Indonesian island five years ago, were also the remains of modern humans.

While on the last day of a holiday in Micronesia in 2006, Professor Lee Berger was told by his guide about a large quantity of bones in a sea-washed cave on a tiny island of Palau. Berger, a paleoanthropologist at Johannesburg's University of the Witwatersrand was thrilled to find thousands of bones in the cave.

Within months, Berger and a group of students and scientists had unearthed the bones and skulls of about 25 individuals in two caves. The smallest specimen was just more than one meter tall, the tallest 1.4 meters.

Bonita de Klerk, a doctoral student at the university, tells VOA the specimens show characteristics of modern humans.

"Well we look at things like the pelvis and also some of morphology on the face, of some of the fragments, so we have indicated they are modern humans in our paper," said de Klerk.

The bones are between 1,400 and 3,000 years old - indicating that the population probably died out about 1,400 years ago.

De Klerk, whose doctoral project is about small-bodied humans, says that in addition to characteristics of modern humans, the little people of Palau also share characteristics with the one-meter-tall, so-called Hobbits discovered in Indonesia in 2003.

Scientists who discovered the bones of several individuals on the island of Flores argue they represent a separate, primitive species of hominid identified by small size, reduced chin, large teeth and small brain. The Palauan individuals also share those characteristics, except for the small brain.

De Klerk argues that since the discovery of the ancient Palauans, it is no longer valid to identify the Hobbits as a separate species.

"In this human population, we are finding some of these very characteristics which they used to describe as significant and they actually based their description of a new species on these certain characteristics. And we are saying if we are finding this in a modern human population, then surely these characteristics should probably not be used to describe a new species," said de Klerk.

Scientists who disagree with the separate species theory argue that dwarfism in modern humans can be caused by a variety of factors. De Klerk says it is either a deformity caused by dietary toxins or an adaptation caused by such things as dietary stress and environmental factors.

"We know that when you are isolated on an island, you undergo adaptations because of things like dietary stress," said de Klerk. "There are no large terrestrial mammals on Palau, so they were probably having a diet of near-shore marine organisms. So things like having no predators, climatic changes, or even this isolation, could all help with this island dwarfism."

Consensus on whether the little people of Indonesia and Palau are modern humans will likely not be reached for some time. Scientists say the discovery on Palau will help determine whether or not modern humans do undergo major size changes in isolated populations.

  原文地址:http://www.tingroom.com/voastandard/2008/3/55123.html