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Macroevolution comprises the evolutionary processes and patterns which occur at and above the species level. [ 1 ] [ 2 ] [ 3 ] In contrast, microevolution is evolution occurring within the population(s) of a single species.
Macroevolution refers to evolution that occurs at or above the level of species, in particular speciation and extinction, whereas microevolution refers to smaller evolutionary changes within a species or population, in particular shifts in allele frequency and adaptation. [135] Macroevolution is the outcome of long periods of microevolution. [136]
Edward Hitchcock's fold-out paleontological chart in his 1840 Elementary Geology. Although tree-like diagrams have long been used to organise knowledge, and although branching diagrams known as claves ("keys") were omnipresent in eighteenth-century natural history, it appears that the earliest tree diagram of natural order was the 1801 "Arbre botanique" (Botanical Tree) of the French ...
Macroevolution – Evolution on a scale at or above the level of species Speciation – Evolutionary process by which populations evolve to become distinct species Natural speciation Allopatric speciation – Speciation that occurs between geographically isolated populations
Evolutionary thought, the recognition that species change over time and the perceived understanding of how such processes work, has roots in antiquity. With the beginnings of modern biological taxonomy in the late 17th century, two opposed ideas influenced Western biological thinking: essentialism, the belief that every species has essential characteristics that are unalterable, a concept ...
However, current evidence in the fossil record supports the concept of mass extinctions. As a result, the general idea of catastrophism has re-emerged as a valid hypothesis for at least some of the rapid changes in life forms that appear in the fossil records. A very large number of fossils have now been discovered and identified.
macroevolution Evolutionary change as it occurs at a relatively large scale, at or above the level of species, as opposed to microevolution, which occurs at a smaller scale. Macroevolution is often thought of as the compounded effects of microevolution. map unit (m.u.) See centimorgan. maternal effect
Evolution is the central unifying concept in biology. Biology can be divided into various ways. Biology can be divided into various ways. One way is by the level of biological organization , from molecular to cell , organism to population .