Homo ergaster may have been the first human species to leave Africa and fossil remains show this species had expanded its range into southern Eurasia by 1.75 million years ago. Their descendents, Homo erectus, then spread eastward and were established in South East Asia by at least 1.6 million years ago.Oct 30, 2015
The poles receive more direct sunshine so it has to do with the angle that the light hits. The Earth is round and when light hits it the light wraps around the earth. At the poles the light is very stretched and at the equator it is very direct hence it is hotter at the poles.
The thin outermost layer of the solid Earth is called the crust. The correct option among all the options given in the question is the second option. The crust actually accounts for less than 1 percent of the volume of the Earth. The Earth can actually be divided into four parts and they are crust, mantle, outer core and inner core.
I belive it it O because <span>An O horizon has at least 20% </span>organic matter<span> by mass. Two main scenarios result in the formation of an O horizon: saturated, </span>anaerobic<span> conditions (wetlands) or high production of leaf litter in forested areas. Anaerobic conditions slow the </span>decomposition<span> process and allow organic material to accumulate. An O horizon can have various stages of decomposed organic matter: highly decomposed, sapric; moderately decomposed, hemic; and minimally decomposed, fibric. In a fibric O layer, plant matter is recognizable (e.g., it is possible to identify a leaf). Sapric material is broken down into much finer matter and is unrecognizable as a plant part. Hemic is in between sapric and fibric, with some barely recognizable plant material present. It is possible to have multiple O horizons stacked upon one another exhibiting different decomposition stages. Because of their organic content, these horizons are typically black or dark brown in color. The dominant processes of the O horizon are </span>additions<span> of organic matter, and </span><span>transformations </span><span>from fibric to sapric
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