Anyone that has eaten chicken knows what a drumstick is - it's the lower leg of a long, spine-like bone, more specifically the fibula, one of the two long bones of the lower leg (the outer one). In dinosaurs, the ancestors of birds, this bone is tube-shaped and reaches all the way down to the ankle, but in evolution birds lost the lower end, and no longer connects to the ankle, being shorter than the other bone in the lower leg, the tibia. In the 19th century, scientists had noted that bird embryos first develop a tubular, dinosaur-like fibula. Only afterwards, it becomes shorter than the tibia and acquires its adult, splinter-like shape.