VOA慢速英語：科學家利用DNA尋找尼斯湖水怪
For hundreds of years, visitors to Scotland's Loch Ness have described seeing a creature that some people believe lives deep in the lake.
But now the story of “Nessie” -- the Loch Ness Monster -- may have no place to hide.
A New Zealand scientist is leading an international team to the lake next month. They plan to take some of the water and study genetic material from the lake to see what species live there.
Neil Gemmell is a professor at the University of Otago in Dunedin, New Zealand. The 51-year-old researcher says he does not believe all the stories about Nessie. But he said he wants to take people on an interesting trip and communicate some science to them along the way. Besides, he added, his children think it is one of the coolest things he has ever done.
One of the more unusual theories is that Nessie is a long-necked dinosaur that somehow survived after other dinosaurs died out.
Another theory is that the creature is actually a large fish, such as a sturgeon or giant catfish. Many people believe the claims of sightings are tricks or can be explained by trees floating in the water or strong winds.
Gemmell said that when creatures move in water, they leave behind small pieces of deoxyribonucleic acid, or DNA. DNA is found in the cells of all animals and plants. It carries their genetic information. DNA comes from their skin, hair and waste fluids.
The New Zealand researcher said his team will take water from different points around the lake and at different depths. After removing the organic material, they will take the DNA, and sequence it by using technology created for the human genome project. The goal of that project was the complete mapping and understanding of all the genes of human beings.
Gemmell said the results of his team’s DNA tests will then be compared against all known species. He said they should have answers by the end of the year.
"I'm going into this thinking it is unlikely there is a monster, but I want to test that hypothesis," Gemmell said, adding that the results will also show “the biodiversity of the Loch Ness."
He noted that the real discoveries may come in finding things like the number of invasive species.
Gemmell said he first visited Loch Ness when he was in his late 20s. Like thousands of visitors before him, he looked out over the lake trying to see a monster. He said he first came up with the idea of testing DNA from the lake a few years ago and many people liked it, including his children.
Graeme Matheson, chief of the Scottish Society of New Zealand, said he, too, had visited Loch Ness and looked for a monster.
"I hope he (Gemmell) and his cohorts find something, although I think they'll be battling," Matheson said. "Still, it's a good way to get a trip to Scotland."
Gemmell said that even if his team fails to find any monster DNA, it won't stop some Nessie believers. He said they have already been offering him theories. One idea is that Nessie might have left the lake and, after a lot of swimming, gone somewhere else for a rest. Another theory is that the monster might be an extraterrestrial, perhaps coming may another planet, and not leave behind any DNA.
"In our lives we want there still to be mysteries, some of which we will solve," Gemmell said, adding that sometimes we find what we were not expecting to find.
I'm Susan Shand.
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Words in This Story
species – n. a group of animals or plants that are similar and can produce young animals or plants
dinosaur – n. one of many reptiles that lived on Earth millions of years ago
sequencing – v. to determine the order in which things happen or should happen
hypothesis – n. an idea or theory that is not proven but that leads to further study or discussion
biodiversity - n. the existence of many different kinds of plants and animals in an environment
cohort – n. a friend or companion
extraterrestrial – n. coming from or existing outside the planet Earth
cool – adj. very good or excellent
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