Fossils are the remains and imprints of plants and animals that lived on Earth in the long past era. But turns into a fossil only a small part of plants and animals. As a rule, their remains are either eaten by other animals or decomposed by the action of fungi and bacteria. Shells or hard bony skeletons persist longer, but eventually they are destroyed. It was only when the remains are buried in the ground very quickly, before they have time to decompose, they have a chance to survive and turn into a fossil. To the deceased plant or animal was buried rapidly, it is necessary that over it there was a sediment, for example sand or silt. Then his remains were soon denied access of air and not rot. Over millions of years of sedimentary layers of the lower pressure of the upper turn into solid rock.
Water that seeps into sedimentary strata, contains minerals. Sometimes she washes them out of the sedimentary material. Under the weight of the upper sedimentary layers of the water displaced from the bottom. Minerals remain within and contribute to the bond of the sedimentary layers and their solidification into rock. These minerals are deposited even in the remains of plants and animals, filling the spaces between their cells, and sometimes even “replacing” their bones or shells. So obratimosti naturally grow in the stone and remain there Continue reading
No place in the world, contains the same number and diversity of fossils of the Jurassic period.
A team of paleontologists led by Dr. Juan Garcia Massini announced the opening of the largest Park of Jurassic period fossils in Patagonia in southern Argentina. The place of burial of the fossils, which were uncovered by recent erosion, it was discovered four years ago and until now was kept secret.
Dr Massini, a geologist from regional research centre reported that this plot is in the area of the massif the Deseado in the province of Santa Cruz in Patagonia.
“This is a unique discovery. Found bones and fossils of flora, micro – and macro-organisms. In addition, the organisms were buried very quickly by mud and fine earth, says Massini. – You can even see how the fungi, cyanobacteria, and worms were moved when they were still alive”.
Excavations are carried out on an area of about 60 thousand square kilometers, and the Massini amazed at how well preserved this area, which is 140 million years old. Continue reading
Anthropogeny — the process of origin and evolution of man.
Driving forces of anthropogenesis.
1)anthropoid ancestors pax; 2)most ancient and ancient ancestors pax; 3)people present, morphologic building.
• individual selection aiming to morphophysiological traits is bipedalism, the structure of the brush, the development of the brain; • group selection, aimed at the social organization; • bio-social selection, the result of the combined action of the first two forms of selection. Acted at the level of individual, family, tribe.
The main driving force of anthropogenesis was the work in which you create your tools. The main factor is labour-was specific to the evolution of the pax. Particularly important was the emergence of a straight gait. Biologically bipedalism brought the man a lot of complications. But due to bipedal locomotion freed the hands for tools. At the beginning of the process of formation of the person his hand was underdeveloped. It took a long time for our ancestors moved from the use of the OCD subjects. nature. environment as weapons in their manufacture. Continue reading