Whales are one of evolution's great enigmas: after life went to all the trouble of adapting to dry land, some mammals decided life was better in the water after all. Philip Gingerich of the University of Michigan has discovered a number of fossils that shed light on the gradual transformation of a furry, four-legged, land-dwelling carnivore into the whales that we know. In the December 22 issue of Publications of the National Academy of Science, he announced the oldest whale fossil yet know, a 53.5-million-year-old creature called Himalayacetus. The creature seemingly lived in a predominantly salt-water environment along the edge of the long-vanished Tethys Sea. It challenges the conventional notion that whales first made the transition to water by hunting for fish in fresh-water rivers.
Despite millions of years of adaptation, many whales now face extinction as a result of hunting by humans. One of the most endangered whales, the northern right whale, is receiving new support from the International Maritime Organization (IMO). Hunting right whales has been illegal since 1937; even so, there are only about 3,000 of them alive today. Under a new IMO proposal, commercial ships will have to report when they enter the birthing or feeding grounds of right whales. The U.S. Coast Guard will then send the ships information about the locations of the whales, preventing the ships from disturbing or colliding with the whales.
--Corey S. Powell
Posted 1/6/99
discover.com
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