jd writes "A comprehensive survey involving sweeping the entire Yangtze River four times with high-sensitivity hydrophones and high-power binoculars turned up not one single living Baiji. The Baiji, also known as the white river dolphin or Lipotes vexillifer, was the last surviving member of the Lipotidae family which split off from the other cetaceans something like 20-40 million years ago. In 1900, it was believed to number in the tens of thousands. By 1999, this had been reduced to 13 due to illegal fishing practices and heavy pollution, both of which were tolerated by corrupt officials. The last two known to have lived died in captivity due to design flaws in their holding pen. Environmental groups are getting serious flak from scientists for being weak and over-cautious in allowing the extinction to happen."