"The biologist Orator F. Cook coined the term in 1906..."
The process by which new species evolve from existing ones.
Darwin's theories of Natural Selection and Adaptive Radiation: Explains how species adapt to their environment over time through the selection of beneficial traits.
Genetic Drift: Explains the role of random genetic mutations in the formation of new species.
Gene Flow: Explains how genetic material is shared between populations (whether it is between individuals of the same species or closely related species).
Isolation Mechanisms: Explains the different methods by which populations can become isolated, such as geographic barriers, behavioral or ecological differences, etc.
Morphological Concepts: Explains the role that physical traits play in the classification and identification of species, particularly with regard to how different species may have evolved from a common ancestor.
Reproductive Barriers: Explains the methods by which two populations that are reproductively isolated may be said to represent different species, such as differences in mating habits, reproductive organs, or the timing of mating.
Hybridization: Explains how the reproductive boundaries between different species can sometimes be blurred, leading to hybrid offspring.
Phylogenetics: Explains the methods used to reconstruct the evolutionary history of different species by comparing their genetic and/or morphological characteristics.
Speciation Models: Explains the different theoretical models that have been proposed to explain how new species arise, including allopatric, sympatric, and parapatric speciation.
Coevolution: Explains the process by which two or more species may evolve in response to one another, particularly in cases where they have a close ecological or evolutionary relationship.
Adaptive Radiation: Explains a common pattern seen in the evolution of different species, particularly in response to new ecological niches opening up over time.
Biogeography: Explains how the patterns of species distribution across the planet can be explained by evolutionary processes such as speciation, extinction, and dispersal.
Convergent Evolution: Explains how species that are not necessarily closely related may evolve similar traits over time, particularly in response to similar environmental pressure.
Microevolution and Macroevolution: Explains the difference between changes that occur within a species over a relatively short period of time (microevolution) versus the long-term implications of these changes, which may ultimately result in the formation of new species (macroevolution).
Evolutionary Developmental Biology (Evo-Devo): Explains the interplay between the genetic and developmental mechanisms that shape the evolution of new species over time.
Allopatric speciation: This occurs when a population is divided into two or more geographically isolated groups, which evolve separately over time due to different environmental pressures and mutations. Over time, the isolated populations may become so different that they can no longer interbreed even if they are reunited.
Sympatric speciation: This occurs when speciation occurs within a single population or geographic area, often due to ecological or behavioral factors that drive reproductive isolation. For example, two populations of the same species might evolve different preferences for certain food sources or mating behaviors, eventually leading to reproductive isolation.
Parapatric speciation: This is a form of speciation that occurs when populations live in different but neighboring areas that are in contact, but without full genetic intermixture. This type of speciation can occur when populations are exposed to different environmental pressures but can still migrate and interbreed.
Peripatric speciation: This occurs when a small population of a larger species becomes geographically isolated and undergoes genetic drift and selection that leads to new phenotypes and, eventually, reproductive isolation from the original population.
Adaptive radiation: This is a type of speciation that occurs when a single species rapidly evolves into multiple different forms, each adapted to a specific ecological niche. This process often occurs after a major environmental change or colonization of a new area with various available resources.
Hybrid speciation: This occurs when two different species interbreed and produce hybrid offspring that are fertile and evolve into a new, distinct species. This type of speciation typically involves a mix of genetic material from both parent species and often involves complex processes of genetic and ecological isolation.
Polyploid speciation: This type of speciation occurs when an individual or population of a species undergoes a change in its chromosome number, often due to errors in cell division. This increase or decrease in chromosome number can lead to changes in the number of genes and their regulation, leading to new phenotypes and potentially reproductive isolation from the original population.
"...cladogenesis, the splitting of lineages, as opposed to anagenesis, phyletic evolution within lineages."
"Charles Darwin was the first to describe the role of natural selection in speciation..."
"He also identified sexual selection as a likely mechanism..."
"There are four geographic modes of speciation in nature..." - Allopatric - Peripatric - Parapatric - Sympatric
"Speciation may also be induced artificially, through animal husbandry, agriculture, or laboratory experiments."
"Whether genetic drift is a minor or major contributor to speciation is the subject of much ongoing discussion."
"Rapid sympatric speciation can take place through polyploidy, such as by doubling of chromosome number..."
"The result is progeny which are immediately reproductively isolated from the parent population."
"New species can also be created through hybridization..."
"...followed by reproductive isolation..."
"Speciation may also be induced artificially, through animal husbandry, agriculture, or laboratory experiments."
"...but found it problematic."
"Charles Darwin... in his 1859 book On the Origin of Species."
"Speciation is the evolutionary process by which populations evolve to become distinct species."
"...the result is progeny which are immediately reproductively isolated from the parent population."
"Rapid sympatric speciation can take place through polyploidy..."
"There are four geographic modes of speciation in nature..."
"Speciation may also be induced artificially, through animal husbandry, agriculture, or laboratory experiments."
"Whether genetic drift is a minor or major contributor to speciation is the subject of much ongoing discussion."