Various grasses, shrubs, and some trees were able to sprout. Some have claimed their models and evidence shows this occurrence happening abruptly, while others have stimulated models showing a gradual change (5).ĥ,000-8,000 year-old Saharan rock art depicting domesticated cows.
However, it should be kept in mind that there is debate over the Sahara's potential savanna-like history. Scientists have also retrieved evidence from Lake Yoa about this mid-Holocene aridification. Unbroken sediments in Saharan waters like Lake Chad also served as evidence of a lusher Sahara thousands of years ago (4). Southwestern Egyptian rock art and human and animal remains from various excavation sites have served as evidence that the new semi-arid conditions encouraged human and animal inhabitance. Thus, Nile Valley dwellers began to settle in this region. This increased precipitation ultimately replenished the land, making it habitable and more-Savanna like (4). Many scientists believe that this was a result of a change in Earth’s orbital shift. Some 10,500 years ago, there was a sudden strengthening of monsoonal rains that occurred in the Sahara Desert. According to the Encyclopedia of Earth, “Plant leaves may dry out totally and then recover animals may loose 30 to 60 percent of their body mass and are still able to recover” (1). It receives less than 2.5 cm (25 mm) of rainfall annually, creating a dry eco-region and influencing the type of plants and animals that inhabit this area (1).Įndemism is low in this region, however the plants and animals that the Sahara does host, have adapted to its sensitive and harsh climate. In fact, it takes up approximately 10% of Africa, or 3.5 million square miles! (1) (Antarctica, in contrast, is the largest desert in the world.) Temperatures in the Sahara are extreme, with very high temperatures during the day (anywhere between 30 degrees Celsius to 50 degrees Celsius) and very low temperatures in the evening (~0 degrees Celsius.) This region experiences a lapse in rainfall, sometimes going without many years of it. The Sahara Desert, located in Northern Africa, is the largest hot desert in the world.
0 kommentar(er)
