Bright pink spots flashed among the trees, gliding between the branches, gracefully encircle the stems, swollen with water. This is a dive into the flooded jungle river Amazon dolphins, they are the same Boat (local) or inii (Inia geoffrensis). Amazon flooded in the rainy season, in its upper reaches flooded jungle, thus giving a chance for a real dolphin forest
hunting.
Boat is almost two and a half feet long and weighs about 200 pounds. Its distinguishing feature - a long, leathery snout-like beak, or sting, which is so easy to dig shellfish from the bottom sediment and fish catch, rushing about in confusion branches.
Why should dolphins, native inhabitants of salty sea water, moved vpresnye water? Healy Hamilton, a biologist at the California Academy of Sciences, explains: about 15 million years ago during the Miocene, the sea level was higher, and so large parts of present South America remained under a layer of salt water. Hamilton's hypothesis is that over time the sea gradually receded to the modern lines, and some dolphins remained in their former territories. And for millions of years in the Amazon, they have become quite amazing creatures, not much like the universal favorite, kinogeroya Flipper.
River dolphins are found not only in the Amazon? they can also be found vindiyskom Ganges, the Indus in Pakistan and in the waters of the Rio de la Plata, between Argentina and Uruguay. There are four species of river dolphins, and Boat - the largest of them.
Until recently, the species of river dolphins was five. However, in the beginning of this century have been completely destroyed dolphins from the Yangtze River China - since 2002, scientists have not been able to find them.
According to Hamilton, at first glance, freshwater dolphins kazhutsyaodinakovymi? however, there are four kinds belong to three different families. Based on DNA analysis, river dolphins, sea earlier split from their common ancestors, the ancestors of cetaceans, at least on three occasions - first in India, then China and South America. The evolution of each of the families was independently and in parallel - and geographically isolated genetically distinct species by adapting to similar conditions, eventually acquired similar characteristics.
Each spring brings a chance to leave the Amazonian dolphins narrow confines of the river bed and think of the endless ancient homeland.
Tony Martin of the University of Kent in England studying dolphins vprirodnom Mamiraua Reserve in the west of Brazil for 16 years. Here, two tributary of the Amazon for six months flooded thousands of square miles of jungle, turning it into a huge lake under a tree crown cover.
Martin and his Brazilian counterpart, Vera da Silva found that females swim deeper vles dolphins - perhaps to hide from aggressive males bright pink. Females are mostly gray in color, but males, according to Martin and da Silva, became a darling pink as a result of multiple injuries.
Pink color - not the only thing that can attract a female. Sometimes the beak boutoberet bunch of plants or a piece of wood starts to whirl and beat his prey in the water. Local residents have long thought that this is just a game, while Martin was not found: objects in the mouth are kept only males - and only in the presence of females.
Martin believes: in nature there are only about 100 thousand Amazonian dolphins, and they are in great danger. For seven years, the population of the reserve Mamiraua halved. Fishermen use dolphin meat as bait for catfish, and often Boat accidentally fall into the network and choking, unable to emerge.
