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Speciation is the evolutionary process by which populations evolve to become distinct species.The biologist Orator F. Cook coined the term in 1906 for cladogenesis, the splitting of lineages, as opposed to anagenesis, phyletic evolution within lineages.
Controversy exists as to whether Charles Darwin recognized a true geographical-based model of speciation in his publication On the Origin of Species. [5] In chapter 11, "Geographical Distribution", Darwin discusses geographic barriers to migration, stating for example that "barriers of any kind, or obstacles to free migration, are related in a close and important manner to the differences ...
[1] [2] Evidence for speciation by reinforcement has been gathered since the 1990s, and along with data from comparative studies and laboratory experiments, has overcome many of the objections to the theory. [3]: 354 [4] [5] Differences in behavior or biology that inhibit formation of hybrid zygotes are termed prezygotic isolation.
Speciation requires a degree of reproductive isolation—that is, a reduction in gene flow. However, it is intrinsic to the concept of a species that hybrids are selected against, opposing the evolution of reproductive isolation, a problem that was recognised by Darwin.
Parapatric speciation – Speciation within a population where subpopulations are reproductively isolated; Sympatric speciation – Evolution of a new species from an ancestor in the same location; Artificial speciation Animal husbandry – Management of farm animals; Plant breeding – Humans changing traits, ornamental/crops
Adaptation affects all aspects of the life of an organism. [24] The following definitions are given by the evolutionary biologist Theodosius Dobzhansky: 1. Adaptation is the evolutionary process whereby an organism becomes better able to live in its habitat or habitats. [25] [26] [27] 2.
This pattern has led to the idea that, because selection acts so strongly on mating traits, it may be involved in the process of speciation. [20] This process of speciation influenced by natural selection is reinforcement, and can happen under any mode of speciation [3]: 355 (e.g. geographic modes of speciation or ecological speciation [21]).
Allopatric speciation (from Ancient Greek ἄλλος (állos) 'other' and πατρίς (patrís) 'fatherland') – also referred to as geographic speciation, vicariant speciation, or its earlier name the dumbbell model [1]: 86 – is a mode of speciation that occurs when biological populations become geographically isolated from each other to an extent that prevents or interferes with gene flow.