● The newt, a small salamander, is remarkable for its ability to regrow body parts, such as its organs, tissues, limbs, and tail. But are the replacement parts as good as the originals? When it comes to the lens of the newt’s eyes, researchers say yes.

Consider: Newts regenerate the lenses in their eyes by converting iris cells into lens cells. To learn more about this process, biologists spent 16 years observing a group of Japanese newts. Eighteen times, the biologists removed the lenses from each newt. Each time, as expected, the newts grew new ones.

By the end of the study, the newts were about 30 years old​—five years beyond their expected life span in the wild. Yet, they were still able to regenerate lenses as quickly as they could when they were younger. In addition, reports the University of Dayton in Ohio, U.S.A., the regenerated lenses “were virtually identical to intact lenses removed from full-grown newts, which had never undergone lens regeneration.” Biologist Panagiotis Tsonis, a member of the team that studied the newts, admits: “Even I was surprised a little.” He described the new lens as “perfect.”

Scientists hope that the newt’s abilities to regrow damaged body parts will help them to understand how to regenerate damaged tissue in humans. “The newt is an excellent source for finding answers to regeneration,” says Tsonis, “particularly as it relates to old age.”

What do you think? Did the newt’s regenerating lens come about by evolution? Or was it designed?

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“Replacement” lenses are virtually identical to the originals

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Top photo: © Vibe Images/​Alamy; middle photo: © Juniors Bildarchiv/​Alamy