A rare ultrasound glimpse at a fetal manta ray reveals that that these graceful fish can “breathe” in the womb.
Unlike most animals that give birth to live young, manta rays don’t have placentas or umbilical cords. That means their fetuses must get nutrients in some other way. Despite the rays’ huge size (they can grow up to 16 feet, or 5 meters, across), marine biologists know little about their lives. New research detailed Tuesday in the journal Biology Letters reveals more than ever before about manta ray pregnancies.