A Critical Reading of Wikipedia "Evolution" https://en.wikipedia.org/wiki/Evolution


Evolution is change in the heritable characteristics (phenotypes,traits ;bodily parts and behaviors ) of biological populations ( species: a population that produces fertile offspring ) over successive generations.[1][2] These characteristics (phenotypes ) are the expressions of genes (genotypes) that are passed on from parents to offspring during reproduction. Different characteristics tend to exist within any given population as a result of mutation, genetic recombination and other sources (?) of genetic variation.[3] Evolution occurs when evolutionary processes such as natural selection (including sexual selection) and genetic drift act on this variation, resulting in certain characteristics becoming more common or rare within a population.[4] The evolutionary pressures that determine whether a characteristic should be common or rare within a population constantly (constantly ?) change, resulting in the change in heritable characteristics arising (no , selected) over successive generations. It is this process of evolution that has given rise to biodiversity at every level of biological organisation, including the levels of species, individual organisms ( there isnt variety in an indivdual; there is variety between individuals of the same species ) and molecules (dna molecules vary ) .[5][6]

The scientific theory of evolution by natural selection was conceived independently by Charles Darwin and Alfred Russel Wallace in the mid-19th century and was set out in detail in Darwin's book On the Origin of Species.[7] Evolution by natural selection was first demonstrated by the observation that more offspring are often produced than can possibly survive "

Charles Brown: This is a fallacy of formulation ; and it is the standard formulatiin ; even Darwin has it , though I think it's political by Darwin. More offspring are produced than can all survive LONG ENOUGH TO REPRODUCE ! All individual animals are mortal , so they all eventually "don't survive"; that is ,die. (There may even be some populations where all live long enough to reproduce !). At any rate , Darwin's idea is that some characteristics are selected for over others selected against; and that those selected for are selected for because they give an advantage in the struggle for existence (struggle to continue to exist before the inevitable demise; not die) over those selected against ; more individuals selected for will reproduce or reproduce more before they die , because they will have a longer average lifetime, and thereby probably have more opportunities to reproduce ( differential mortality determines differential fertility).

Sexual selection or being selected by the opposite sex because of some bodily or behavioral characteristic directly selects for more matings and therefore likely more fertile matings



CONTINUATION OF WIKIPEDIA ITEM This is followed by three observable facts about living organisms: (1) traits vary among individuals with respect to their morphology, physiology and behaviour (phenotypic variation), (2) different traits confer different rates of survival and reproduction (differential fitness) and (3) traits can be passed from generation to generation (heritability of fitness).[8] Thus, in successive generations members of a population are more likely to be replaced by the progenies of parents with favourable characteristics that have enabled them to survive and reproduce in their respective environments. In the early 20th century, other competing ideas of evolution such as mutationism and orthogenesis were refuted as the modern synthesis reconciled Darwinian evolution with classical genetics, which established adaptive evolution as being caused by natural selection acting on Mendelian genetic variation.[9]

All life on Earth shares a last universal common ancestor (LUCA)[10][11][12] that lived approximately 3.5–3.8 billion years ago.[13] The fossil record includes a progression from early biogenic graphite,[14] to microbial mat fossils,[15][16][17] to fossilised multicellular organisms. Existing patterns of biodiversity have been shaped by repeated formations of new species (speciation), changes within species (anagenesis) and loss of species (extinction) throughout the evolutionary history of life on Earth.[18] Morphological and biochemical traits are more similar among species that share a more recent common ancestor, and can be used to reconstruct phylogenetic trees.[19][20]

Evolutionary biologists have continued to study various aspects of evolution by forming and testing hypotheses as well as constructing theories based on evidence from the field or laboratory and on data generated by the methods of mathematical and theoretical biology. Their discoveries have influenced not just the development of biology but numerous other scientific and industrial fields, including agriculture, medicine and computer science.[21]

History of evolutionary thought