Earth is experiencing its sixth mass extinction: somewhere between 30 and 159 species disappear every day, and more than 300 types of animals have died out since 1500. This is not good for the future of life on our planet, but what if we could make some of the extinct species come back to life? Thanks to ongoing advances in DNA recovery and cloning technology, de-extinction（灭绝动物复活） may soon be realized, and we may see Tasmanian Tigers, or Dodo Birds back into existence in the near future.
Some scientists are confident and optimistic about de-extinction. They think that the best reasons for de-extinction have more to do with ecology than tourism. "If this is always going to be a zoo animal, then stop," says Ben Novak, the lead researcher at Revive & Restore—a foundation devoted to rescuing endangered and extinct species in San Francisco, California. "The goals have to be about ecological restoration and function."
Take passenger pigeons for example. Their numbers reached nearly 5 billion at the start of the 19th century, and they played an important role in shaping the forests they inhabited(居住). After their extinction, the forests have never been the same. "The passenger pigeon is a very important ecological species if we want their original habitat back." Novak says.
However, we need to think twice about Novak's idea. Any new scientific initiative (倡议；新方案) is bound to have risks, so is de-extinction. Although some assume that de-extinction may help the environment, we can't be so sure. The de-extinct animals would now be strangers to their habitats. As the habitat is no longer what it was, the species role within the ecosystem may have also changed. This could be actually a threat to the other species within the environment as the de-extinct animals enter the area and compete for food sources. Once again we're trying to force nature to act in a certain way, rather than letting it remain natural.
Many scientists also believe that priorities(优先权) would change within the conservation of currently endangered species. Would we still put in the effort to preserve living animals if we knew we could just magically bring them back from the dead? Douglas McCauley, an ecologist at University of California, Santa Barbara, stresses this worry. "Honestly, the thing that scares me most is that the public absorbs the misimpression that extinction is no longer scary. The general attitude becomes: Deforest, no worry, we can reforest. If we drive something extinct, no worry, we can de-extinct it. " said McCauley.
It seems that with the subject of de-extinction, we must look at our reasons for doing such a thing. Yes, we may, in the near future, be able to de-extinct the extinct species. But does that mean we should? Are the risks really worth it? Does it make sense to focus on the dead than the living? And who are we truly benefiting in the end?
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