On February 2, groundhog weatherman Punxsutawney Phil roused from hibernation to predict six more weeks of winter. Scientists may snicker at people who think they can learn about the arrival of spring from a furry rodent, but researchers aren’t laughing when it comes to learning about human health from animals that check out for the winter. Understanding how hibernators, including ground squirrels, marmots and bears, survive their long winter’s naps may one day offer solutions for problems such as heart disease, osteoporosis and muscular dystrophy. Despite appearances, hibernation is not... (p. 26)

Feat suggests embryonic stem cells are less flexible in primates than mice. (p. 15)

A compound that blocks DNA unwinding can spur production of a critical brain protein in mice, leading to hope for a therapy for Angelman syndrome. (p. 8)

Naked mole rats don’t feel the burn of acid thanks to tweaks in a protein involved in sending pain messages to the brain. (p. 17)

Eyes can be grown in a frog’s gut by changing cells’ electrical properties, scientists find, opening up new possibilities for generating and regenerating complex organs. (p. 5)

Little hairlike appendages in brain cells control weight by sequestering an appetite hormone.