Phylogenetic data bearing on the REM sleep learning connection

The phylogenetic data arc inconsistent with the hypothesis that REM sleep d uration is correlated with learning or learning ability. Humans do not have uniquely high amounts of REM sleep. The platypus. marsupials, and other ma mmals not generally thought to have extraordinary-learning abilities have t he largest amounts of REM sleep. The whales and dolphins (cetacean,) have t he lowest amounts of REM sleep and may go without REM sleep for extended pe riods of time, despite their prodigious learning abilities.