CHICAGO (AP) -- A rare rattlesnake has given birth to four babies at Chicago’s Lincoln Park Zoo.

Earlier this year officials with the U.S. Fish and Wildlife Service and the Illinois Department of Natural Resources went on an emergency species survival effort and collected eastern massasauga rattlesnakes.

Officials say one male and one female were taken to Lincoln Park Zoo and protected. They’ve been referred to as Adam and Eve, although zoo officials say it’s unclear if Adam sired the babies.

Scientists say Eve may have bred before she was taken to the zoo.

The massasauga is on Illinois’ endangered species list. The snakes were once common to the Chicago area, but now can only be found in one area wetland.