Southern Right Whale Breached On A Ship

"Whale lice", parasitic cyamid crustaceans that live off skin debris, offer information through their own genetic patterns. Lice genetic diversity is greater than whales' because lice reproduce more quickly. Marine biologists at the University of Utah examined lice genes and determined that their hosts split into three species 5–6 million years ago, and that these species were equally abundant before whaling began in the 11th century.