Editing Earless seal (section)

===Growth and maturation===

The pup's diet is so high in [[Calorie|calories]] that it builds up a fat store. Before the pup is ready to forage, the mother abandons it, and the pup consumes its own fat for weeks or even months while it matures. Seals, like all marine mammals, need time to develop the oxygen stores, swimming muscles, and neural pathways necessary for effective diving and foraging. Seal pups typically eat no food and drink no water during the period, although some polar species eat snow. The postweaning fast ranges from two weeks in the hooded seal to 9–12 weeks in the northern elephant seal.<ref>{{Cite journal|title = The energetics of lactation in the Northern elephant seal, ''Mirounga angustirostris''|journal = Journal of Zoology|date = 1986|pages = 21–33|volume = 209|issue = 1|doi = 10.1111/j.1469-7998.1986.tb03563.x|first1 = D. P.|last1 = Costa|first2 = B. J. Le|last2 = Boeuf|first3 = A. C.|last3 = Huntley|first4 = C. L.|last4 = Ortiz}}</ref> The physiological and behavioral adaptations that allow phocid pups to endure these remarkable fasts, which are among the longest for any mammal, remain an area of active study and research.