VOA标准英语2009-New Model Predicts Mammal Extinction

Researchers have developed a new computer model that they say helps determine which mammals are headed for extinction¹ as a result of human activity.

Earth is undergoing its sixth mass extinction, threatening about a quarter of all mammal species, according to Ana Davidson, an international conservation researcher with the University of New Mexico in Albuquerque and the University of Mexico in Mexico City.

Davidson says the threat to mammals is being driven by a number of factors, including climate change, deforestation and poaching.
　
A one-month-old Eurasian Lynx cuddles with her mother at the Sofia Zoo in Bulgaria (File)

"You name it, we're doing it. We are having widespread impacts on the Earth. Right now, 83 percent of the land surface is impacted in some way by humans. And so, that means that the millions of species that we share this planet with are being constrained² and impacted by our activities," she said.

Davidson and several other animal conservationists developed a model to predict the extinction rates of endangered mammals identified by the International Union for the Conservation of Nature, or IUCN.
　
A Fishing Cat views visitors at the Oklahoma City Zoo in Oklahoma City (File)

The list includes more than 1,100 threatened animals, some of which have been put in the critically endangered category, such as the Iberian lynx. Others, including the Fishing Cat of Southeast Asia, are listed as endangered because of habitat loss.

Davidson says the model is designed to keep track of which mammals are at risk in the future by factoring in a number of ecological³ considerations, such the amount of land where they roam.

"If an animal lives in the ground or in trees or in the ocean that kind of thing. Also, [we] use group size, which is a measure of an animal's sociality. We use life history data, which tells us how fast an animal species reproduces; things like that," she said.

Davidson says larger animal species are at greater risk of extinction than smaller mammals because they are frequently in conflict with carnivores for land and food, and they do not produce many offspring.

Davidson says the model is an attempt to help animal preservationists target their resources.

"Our funding is very limited, right? So to be able to have these sorts of guidelines, to be able to focus in and hone our efforts, is really important," said Davidson.

The researchers describe their animal conservation model in the Proceedings⁴ of the National Academy of Sciences.

1 extinction   

n.熄灭，消亡，消灭，灭绝，绝种

参考例句：

• The plant is now in danger of extinction.这种植物现在有绝种的危险。
• The island's way of life is doomed to extinction.这个岛上的生活方式注定要消失。

2 constrained   

adj.束缚的,节制的

参考例句：

• The evidence was so compelling that he felt constrained to accept it. 证据是那样的令人折服，他觉得不得不接受。
• I feel constrained to write and ask for your forgiveness. 我不得不写信请你原谅。

3 ecological   

adj.生态的，生态学的

参考例句：

• The region has been declared an ecological disaster zone.这个地区已经宣布为生态灾难区。
• Each animal has its ecological niche.每种动物都有自己的生态位.

4 proceedings   

n.进程，过程，议程；诉讼(程序)；公报

参考例句：

• He was released on bail pending committal proceedings. 他交保获释正在候审。
• to initiate legal proceedings against sb 对某人提起诉讼