The evolution of sexual reproduction is a great puzzle in modern evolutionary biology. Many groups of eukaryotic organisms, especially most animals and plants, reproduce sexually. The evolution of sex between two organisms of the same species contains two related but different themes: its origin and its maintenance. However, since hypotheses for the origin of sex are difficult to test experimentally, most of the current work has focused on the maintenance of sexual reproduction. Biologists, including W. D. Hamilton, Alexei Kondrashov, and George C. Williams, have proposed various explanations for how sexual reproduction is maintained in a large set of different living things.
It is a protein and it functions in a red blood cell to help carry oxygen
The first evidence of modern human traits, including increasing brain size and dependence on material culture shows up in Homo habilis. Even though they are species<span> of genus </span>Homo, they are not similar to people nowadays at all. <span>In </span>palaeoanthropology, these species were the first ones who left Africa and started to move and spread along Eurasia, which is one the main facts and characteristics of Homo habilis.
It is free to bind to another promoter and begin transcription.
