orcas

[Image by BarnyardBBS.]

Postpartum Sleep in Whales and Dolphins

A random brief video: wakefulness in newborn cetaceans and mothers, accompanying a Brief Communication published in Nature, 2005 (PDF). “…unilateral or bilateral eye closure was almost never (for less than 0.4% of 24 h) observed in dolphin mothers during the first 2 months postpartum.” 24 hr video surveillance confirmed human observations of the mothers keeping a near-continuous eye on offspring. Development and parenting occur without much rest “in contrast to the pattern seen so far in other animals, from flies to mammals,” conclude researchers Lyamin et al. Supplemental info PDF here, and the video supplement features a cute baby orca.

rb2_small Lyamin, O., Pryaslova, J., Lance, V., & Siegel, J. (2005). Animal behaviour: Continuous activity in cetaceans after birth Nature, 435 (7046), 1177-1177 DOI: 10.1038/4351177a