The lady Galapagos tortoise likes to play hard to get, so males have to chase females before mating. During mating (which can last several hours) the couple fit together like spoons due to the males having a shell with a concave base (intelligent design for sexy times!) It may take the female up to five hours to build her nest, and the temperature of the nest plays a role in determining the sex of the hatchlings. It may take young tortoises up to a month to dig their way to the surface of the nest after hatching. Taronga zoo-keepers say "Courting has been said to begin with the male ramming the female with the front of his shell and nipping her exposed legs until she draws them in, immobilizing herself. However our keepers have also observed that copulation can occur by the female elevating the back end of her shell and stretching her cloaca open and positioned towards him. Our female tortoise has even been observed to help the male with his aim, guiding him with her back feet."