The scientific inquiry into the origin of species can be dated to at least the 6th century BCE, with the Greek philosopher Anaximander.[14] Others who considered evolutionary ideas included the Greek philosopher Empedocles, the Roman philosopher-poet Lucretius, the Afro-Arab biologist Al-Jahiz,[15] the Persian philosopher Ibn Miskawayh, the Brethren of Purity,[16] and the Chinese philosopher Zhuangzi.[17] As biological knowledge grew in the 18th century, evolutionary ideas were set out by a few natural philosophers including Pierre Maupertuis in 1745 and Erasmus Darwin in 1796.[18] The ideas of the biologist Jean-Baptiste Lamarck about transmutation of species influenced radicals, but were rejected by mainstream scientists. Charles Darwin formulated his idea of natural selection in 1838 and was still developing his theory in 1858 when Alfred Russel Wallace sent him a similar theory, and both were presented to the Linnean Society of London in separate papers.[19] At the end of 1859, Darwin's publication of On the Origin of Species explained natural selection in detail and presented evidence leading to increasingly wide acceptance of the occurrence of evolution.
Debate about the mechanisms of evolution continued, and Darwin could not explain the source of the heritable variations which would be acted on by natural selection. Like Lamarck, he thought that parents passed on adaptations acquired during their lifetimes,[20] a theory which was subsequently dubbed Lamarckism.[21] In the 1880s, August Weismann's experiments indicated that changes from use and disuse were not heritable, and Lamarckism gradually fell from favour.[22][23] More significantly, Darwin could not account for how traits were passed down from generation to generation. In 1865 Gregor Mendel found that traits were inherited in a predictable manner.[24] When Mendel's work was rediscovered in 1900s, disagreements over the rate of evolution predicted by early geneticists and biometricians led to a rift between the Mendelian and Darwinian models of evolution.
Yet it was the rediscovery of Gregor Mendel’s pioneering work on the fundamentals of genetics (of which Darwin and Wallace were unaware) by Hugo de Vries and others in the early 1900s that provided the impetus for a better understanding of how variation occurs in plant and animal traits. That variation is the main fuel used by natural selection to shape the wide variety of adaptive traits observed in organic life. Even though Hugo de Vries and other early geneticists rejected gradual natural selection, their rediscovery of and subsequent work on genetics eventually provided a solid basis on which the theory of evolution stood even more convincingly than when it was originally proposed.[25]
The apparent contradiction between Darwin’s theory of evolution by natural selection and Mendel’s work was reconciled in the 1920s and 1930s by evolutionary biologists such as J.B.S. Haldane, Sewall Wright, and particularly Ronald Fisher, who set the foundations for the establishment of the field of population genetics. The end result was a combination of evolution by natural selection and Mendelian inheritance, the modern evolutionary synthesis.[26] In the 1940s, the identification of DNA as the genetic material by Oswald Avery and colleagues and the subsequent publication of the structure of DNA by James Watson and Francis Crick in 1953, demonstrated the physical basis for inheritance. Since then, genetics and molecular biology have become core parts of evolutionary biology and have revolutionized the field of phylogenetics.[12]
In its early history, evolutionary biology primarily drew in scientists from traditional taxonomically oriented disciplines, whose specialist training in particular organisms addressed general questions in evolution. As evolutionary biology expanded as an academic discipline, particularly after the development of the modern evolutionary synthesis, it began to draw more widely from the biological sciences.[12] deals with several areas where the modern evolutionary synthesis may need modification or extension, such as assessing the relative importance of various ideas on the Currently the study of evolutionary biology involves scientists from fields as diverse as biochemistry, ecology, genetics and physiology, and evolutionary concepts are used in even more distant disciplines such as psychology, medicine, philosophy and computer science. In the 21st century, current research in evolutionary biologyunit of selection and evolvability and how to fully incorporate the findings of evolutionary developmental biology.
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