Fish farming, practiced in Ancient Egypt, as evidenced by the sources dated about 2000 BC, over four thousand years ago. In Mesopotamia, in temples the priests kept the fish in ponds. Fish were kept in ponds in ancient Rome and Greece.
But only in China began to engage in purposeful breeding of different breeds of fish, which we know under the name goldfish.
To the right is a detail of a mural in Egyptian tomb, which depicts a pond with fish
Goldfish is the usual subspecies of the goldfish ( Carassius auratus ). It is assumed that the subspecies living in China, was separated from the rest of toothcarps formed millions of years ago mountains. This subspecies, which is West of the Himalayas is not found, when it was developed ornamental goldfish.
Left – map showing the distribution of toothcarps ( Cypridontae ), to which the goldfish belongs, and the primary habitat of a goldfish. In the wild this fish niceley rivers, lakes, ponds and all dents filled with water. Carp undemanding and can live in flowing and stagnant water. In nature, fish may have different color variations, depending on ambient conditions. The most important of these conditions is light. Continue reading
Red sea — most beautiful sea in the world . This title rightly belongs to him. Is the sea really fascinates by the diversity of colors and shapes.
The red sea is a tectonic depression and is an inland sea of the Indian ocean, it is the youngest and considered by many the most beautiful, interesting variety of flora and fauna.
Despite the fact that the Red sea is the most salty seas are part of oceans, it amazes even experienced divers the beauty and diversity of different creatures living in it. The red sea is the most salty because it, unlike all the other seas of the world, no freshwater flows into the river. Of course, it is much inferior to the salt content of the Dead sea, but it is known not to survive in fact a single living organism. The salinity of the beautiful red sea reaches 60 grams of salt per liter of water. In the Black sea – only 18 grams of salt per liter of water.
Besides, describing the Red sea, which is assigned to one of the 7 wonders of the underwater world, it must be remembered that it is also the warmest sea on Earth. All because its not only warm rays of the sun but also the earth surface, mantle, and in the Red sea, unlike other seas, from the depths, from the bottom podnimayutsya cold, but rather warm layers of water. In winter the water is heated to 21 – 23 degrees Celsius, and in summer even up to +30. Largely because of the high temperature of sea water and its continuous evaporation of this sea is the most saline in the world after the Dead. Continue reading