Sea snakes, which are also elapids, have adapted to a marine way of life in different ways. All have evolved their tails so they can be used for swimming. They can also excrete salt. Most also have changed bodies, better suited for swimming. Ventral scales are much smaller, the nostrils of the snakes are located dorsally and without scales between them. They give birth to live young (ovoviviparous). In general they have the ability to breathe through their skin; experiments with the yellow-bellied sea snake, "Pelamis platurus", have shown that this species can satisfy about 20% of its oxygen requirements in this manner. This makes it possible to stay underwater longer. The sea kraits ("Laticauda sp. "), are the least well-adapted to an aquatic life. They spend much of their time on land where they also lay their eggs (oviparous). They have wide ventral scales, the tail is not as well-developed for swimming, and their nostrils are separated by scales.