Anagenesis

anageneticanageneticallyanagenetic evolutionanagenic evolutiongradually changedPhyletic evolutionpopulations changing over generationsPseudoterminationsequential development pattern
Anagenesis is the gradual evolution of a species that continues to exist as an interbreeding population.wikipedia
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Evolution

evolvedtheory of evolutionevolutionary
Anagenesis is the gradual evolution of a species that continues to exist as an interbreeding population.
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.

Speciation

divergedspeciatedspeciate
When speciation does occur as different lineages branch off and cease to interbreed, a core group may continue to be defined as the original species. This is in contrast to cladogenesis—or speciation in a sense—in which a population is split into two or more reproductively isolated groups and these groups accumulate sufficient differences 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.

Extinction

extinctspecies extinction
The evolution of this group, without extinction or species selection, is anagenesis.
Effectively, the old taxon vanishes, transformed (anagenesis) into a successor, or split into more than one (cladogenesis).

Species

specificspecific epithetspecific name
Anagenesis is the gradual evolution of a species that continues to exist as an interbreeding population.
During anagenesis (evolution, not necessarily involving branching), palaeontologists seek to identify a sequence of species, each one derived from the phyletically extinct one before through continuous, slow and more or less uniform change.

Punctuated equilibrium

punctuated equilibriastasisequilibrium
The punctuated equilibria hypothesis suggests that anagenesis is rare and that the rate of evolution is most rapid immediately after a split which will lead to cladogenesis, but does not completely rule out anagenesis.
Punctuated equilibrium is commonly contrasted against phyletic gradualism, the idea that evolution generally occurs uniformly and by the steady and gradual transformation of whole lineages (called anagenesis).

Cladogenesis

splitcladogeneticsplitting
This contrasts with cladogenesis, which occurs when there is branching or splitting, leading to two or more lineages and resulting in separate species. If the ancestral population of a chronospecies does not go extinct, then this is cladogenesis, and the ancestral population represents a paraphyletic species or paraspecies, being an evolutionary grade.
Cladogenesis is in contrast to anagenesis, in which an ancestral species gradually accumulates change, and eventually, when enough is accumulated, the species is sufficiently distinct and different enough from its original starting form that it can be labeled as a new form - a new species.

Chronospecies

paleosubspeciesPaleospeciesfaunal turnover
The various species along an evolutionary lineage are chronospecies.
A chronospecies is a species derived from a sequential development pattern which involves continual and uniform changes from an extinct ancestral form on an evolutionary scale.

Paraphyly

paraphyleticembedded*
If the ancestral population of a chronospecies does not go extinct, then this is cladogenesis, and the ancestral population represents a paraphyletic species or paraspecies, being an evolutionary grade.
Ereshefsky has argued that paraphyletic taxa are the result of anagenesis in the excluded group or groups.

Australopithecus anamensis

Praeanthropus anamensisA. anamensisPraeanthropus anamensis (Australopithecus anamensis)
Recent evolutionary studies are looking at anagenesis and cladogeneis for possible answers in developing the hominin phylogenetic tree to understand morphological diversity and the origins of Australopithecus anamensis, and this case could possibly show anagenesis in the fossil record.
afarensis'' were in fact one evolving species (i.e. a chronospecies resulting from anagenesis), but in August 2019, scientists from the same Haile-Selassie team announced the discovery of a nearly intact skull for the first time, and dated to 3.8 mya, of ''A.

Social evolution

evolution of the societiessocialsocial evolutionary theories
Regarding social evolution, it has been suggested that social anagenesis/aromorphosis be viewed as universal or widely diffused social innovation that raises social systems' complexity, adaptability, integrity, and interconnectedness.

Paraspecies

paraphyletic speciation
If the ancestral population of a chronospecies does not go extinct, then this is cladogenesis, and the ancestral population represents a paraphyletic species or paraspecies, being an evolutionary grade.

Unit of selection

units of selectionlevels of selectionspecies selection
The evolution of this group, without extinction or species selection, is anagenesis.

Genetic variation

variationinterindividual variabilitygenetic variations
One hypothesis is that during the speciation event in anagenetic evolution, the original populations will increase quickly, and then rack up genetic variation over long periods of time by mutation and recombination in a stable environment.

Mutation

mutationsgenetic mutationmutated
One hypothesis is that during the speciation event in anagenetic evolution, the original populations will increase quickly, and then rack up genetic variation over long periods of time by mutation and recombination in a stable environment.

Genetic recombination

recombinationmeiotic recombinationDNA recombination
One hypothesis is that during the speciation event in anagenetic evolution, the original populations will increase quickly, and then rack up genetic variation over long periods of time by mutation and recombination in a stable environment.

Natural selection

selectionselectiveselected
Other factors such as selection or genetic drift will have such a significant effect on genetic material and physical traits that a species can be acknowledged as being different from the previous.

Genetic drift

driftrandom genetic driftrandom drift
Other factors such as selection or genetic drift will have such a significant effect on genetic material and physical traits that a species can be acknowledged as being different from the previous.

Genome

genomesgenetic materialgenomic
Other factors such as selection or genetic drift will have such a significant effect on genetic material and physical traits that a species can be acknowledged as being different from the previous.

Reproductive isolation

reproductively isolatedisolating mechanismsisolating mechanism
This is in contrast to cladogenesis—or speciation in a sense—in which a population is split into two or more reproductively isolated groups and these groups accumulate sufficient differences to become distinct species.

Evolutionary grade

gradegradesgrade taxon
If the ancestral population of a chronospecies does not go extinct, then this is cladogenesis, and the ancestral population represents a paraphyletic species or paraspecies, being an evolutionary grade.

Milford H. Wolpoff

Milford WolpoffWolpoff
Milford H. Wolpoff is paleoanthropologist whose work done when studying human fossil records explored anagenesis as a hypothesis for hominin evolution.

Paleoanthropology

paleoanthropologistpaleoanthropologicalpaleoanthropologists
Milford H. Wolpoff is paleoanthropologist whose work done when studying human fossil records explored anagenesis as a hypothesis for hominin evolution.

Hominini

homininhomininsHominan
Milford H. Wolpoff is paleoanthropologist whose work done when studying human fossil records explored anagenesis as a hypothesis for hominin evolution.

Pliocene

Pliocene epochLate PlioceneEarly Pliocene
Examining early Pliocene and late Miocenes findings helps to determine the corresponding importance of anagenesis vs. cladogenesis during the period of morphological differences.

Miocene

Late MioceneEarly MioceneMiddle Miocene
Examining early Pliocene and late Miocenes findings helps to determine the corresponding importance of anagenesis vs. cladogenesis during the period of morphological differences.