February 22

Scientists Grow Baby Sheep from Adult Cells!

On this day in 1997, scientists in Scotland introduced to the world an eight-month-old sheep named Dolly. She was the first living creature to be successfully cloned from the cells of an adult mammal. Cloning involves copying information in an organism's cells to create an identical organism.

Cloning adult animals remains a tricky process—it took scientists 276 tries before they were successful in cloning Dolly. Dolly's existence raises new questions about the possibilities of genetic cloning.