
https://www.nytimes.com/2025/04/29/scien...=url-share
EXCERPTS: Compared with her own experiences with nicks and cuts, the baboons’ ability to heal seemed like a superpower.
In a study published on Wednesday in Proceedings of the Royal Society B, Dr. Matsumoto-Oda and her colleagues compared the healing rates of humans, chimpanzees, monkeys and mice. They found that human wounds took more than twice as long to heal as wounds of any of the other mammals. Our slow healing may be a result of an evolutionary trade-off we made long ago, when we shed fur in favor of naked, sweaty skin that keeps us cool.
[...] What surprised Dr. Matsumoto-Oda more was the consistency between the healing rates of the animal subjects, including chimpanzees. There was no significant difference in the speedy skin regrowth among different primates, which grew about 0.62 millimeters of new skin per day, or between primates and rodents. Humans were the clear outliers.
Elaine Fuchs, a stem cell biologist at the Rockefeller University who studies skin growth and repair and was not involved in the new research, said the results were what she would have expected. That’s because skin healing depends on hair.
Each hair grows from a hair follicle, which also houses stem cells. Normally, those stem cells just make more hair. But when called upon, they can grow new skin instead. “When the epidermis is wounded, as in most kinds of scratches and scrapes, it’s really the hair-follicle stem cells that do the repair,” Dr. Fuchs said.
Furry animals are covered in follicles, which help quickly close up wounds in mice or monkeys. By comparison, “human skin has very puny hair follicles,” Dr. Fuchs said. And our ancestors lost many of those follicles, packing their skin with sweat glands instead. Sweat glands also have stem cells, but they’re much less efficient at repairing wounds, Dr. Fuchs said... (MORE - missing details)
EXCERPTS: Compared with her own experiences with nicks and cuts, the baboons’ ability to heal seemed like a superpower.
In a study published on Wednesday in Proceedings of the Royal Society B, Dr. Matsumoto-Oda and her colleagues compared the healing rates of humans, chimpanzees, monkeys and mice. They found that human wounds took more than twice as long to heal as wounds of any of the other mammals. Our slow healing may be a result of an evolutionary trade-off we made long ago, when we shed fur in favor of naked, sweaty skin that keeps us cool.
[...] What surprised Dr. Matsumoto-Oda more was the consistency between the healing rates of the animal subjects, including chimpanzees. There was no significant difference in the speedy skin regrowth among different primates, which grew about 0.62 millimeters of new skin per day, or between primates and rodents. Humans were the clear outliers.
Elaine Fuchs, a stem cell biologist at the Rockefeller University who studies skin growth and repair and was not involved in the new research, said the results were what she would have expected. That’s because skin healing depends on hair.
Each hair grows from a hair follicle, which also houses stem cells. Normally, those stem cells just make more hair. But when called upon, they can grow new skin instead. “When the epidermis is wounded, as in most kinds of scratches and scrapes, it’s really the hair-follicle stem cells that do the repair,” Dr. Fuchs said.
Furry animals are covered in follicles, which help quickly close up wounds in mice or monkeys. By comparison, “human skin has very puny hair follicles,” Dr. Fuchs said. And our ancestors lost many of those follicles, packing their skin with sweat glands instead. Sweat glands also have stem cells, but they’re much less efficient at repairing wounds, Dr. Fuchs said... (MORE - missing details)