A compilospecies is a genetically aggressive species which acquires the heredities of a closely related

sympatric In biology, two related species or populations are considered sympatric when they exist in the same geographic area and thus frequently encounter one another. An initially interbreeding population that splits into two or more distinct species s ...

species by means of hybridisation and comprehensive

introgression Introgression, also known as introgressive hybridization, in genetics is the transfer of genetic material from one species into the gene pool of another by the repeated backcrossing of an interspecific hybrid with one of its parent species. Intro ...

. The target species may be incorporated to the point of despeciation, rendering it extinct. This type of genetic aggression is associated with species in newly disturbed habitats (such as

pioneering species Pioneer species are hardy species that are the first to colonize barren environments or previously biodiverse steady-state ecosystems that have been disrupted, such as by wildfire. Pioneer flora Some lichens grow on rocks without soil, so m ...

), weed species and domestication. They can be

diploid Ploidy () is the number of complete sets of chromosomes in a cell, and hence the number of possible alleles for autosomal and pseudoautosomal genes. Sets of chromosomes refer to the number of maternal and paternal chromosome copies, respecti ...

polyploid Polyploidy is a condition in which the cells of an organism have more than one pair of (homologous) chromosomes. Most species whose cells have nuclei (eukaryotes) are diploid, meaning they have two sets of chromosomes, where each set contain ...

, as well as sexual or primarily asexual. The term compilospecies derives from the Latin word compilo, which means to seize, to collect, to rob or to plunder. A proposed explanation for the existence of such a species with weak reproductive barriers and frequent introgression is that it allows for

genetic variation Genetic variation is the difference in DNA among individuals or the differences between populations. The multiple sources of genetic variation include mutation and genetic recombination. Mutations are the ultimate sources of genetic variation, b ...

. An increase in the

gene pool The gene pool is the set of all genes, or genetic information, in any population, usually of a particular species. Description A large gene pool indicates extensive genetic diversity, which is associated with robust populations that can surv ...

through viable hybrids can facilitate new

phenotype In genetics, the phenotype () is the set of observable characteristics or traits of an organism. The term covers the organism's morphology or physical form and structure, its developmental processes, its biochemical and physiological prop ...

s and the colonisation of novel habitats. The concept of compilospecies is not frequent in scientific literature and may not be fully regarded by the biological community as a true evolutionary concept, especially due to low supporting evidence.

History

Compilospecies were first described by Harlan and de Wet in 1962, who examined a wide range of grasses and other species such as '' Bothriochloa intermedia'', otherwise known as Australian bluestem grass. ''B. intermedia'' was found to introgress heavily with neighboring sympatric grass species and even genera, particularly in geographically restricted areas. The species itself is of hybrid origin, containing genetic material from five or more different grass species. Harlan and de Wet examined the interactions between the genera ''

Bothriochloa ''Bothriochloa'' is a common and widespread genus of plants in the grass family native to many countries on all inhabited continents and many islands. They are often called beardgrass, bluegrass or bluestem. The etymology of the genus name ''Bo ...

Dichanthium ''Dichanthium'', known commonly as bluestem or bluegrass, is a genus of African, Asian, and Australian plants in the grass family. Some species have become naturalized in the Americas and on various oceanic islands.Bhat, V., et alChapter 6: ' ...

and Capillipedium'' - an

apomictic In botany, apomixis is asexual reproduction without fertilization. Its etymology is Greek for "away from" + "mixing". This definition notably does not mention meiosis. Thus "normal asexual reproduction" of plants, such as propagation from cutt ...

complex of grasses from the tribe

Andropogoneae The Andropogoneae, sometimes called the sorghum tribe, are a large tribe of grasses (family Poaceae) with roughly 1,200 species in 90 genera, mainly distributed in tropical and subtropical areas. They include such important crops as maize (corn), ...

- and used the

cytogenetic Cytogenetics is essentially a branch of genetics, but is also a part of cell biology/cytology (a subdivision of human anatomy), that is concerned with how the chromosomes relate to cell behaviour, particularly to their behaviour during mitosis an ...

model of these as a basis for the compilospecies concept. Species within these genera exhibit both sexual and asexual reproduction, high heteriozygosity, ploidies from 2x to 6x, and gene flow between bordering populations as evidence of ongoing introgression. However, this

gene flow In population genetics, gene flow (also known as gene migration or geneflow and allele flow) is the transfer of genetic material from one population to another. If the rate of gene flow is high enough, then two populations will have equivalen ...

is only made possible in the presence of ''B. intermedia'', which introgression moves towards, and the absence of which keeps the other species

reproductively isolated The mechanisms of reproductive isolation are a collection of evolutionary mechanisms, behaviors and physiological processes critical for speciation. They prevent members of different species from producing offspring, or ensure that any offspring ...

. ''B. intermedia'' is identified as the compilospecies in this model.

Further examples

Other researched examples of compilospecies include; * ''

Helianthus ''Helianthus'' () is a genus comprising about 70 species of annual and perennial flowering plants in the daisy family Asteraceae commonly known as sunflowers. Except for three South American species, the species of ''Helianthus'' are native to ...

'' (sunflowers) * ''

Draba ''Draba'' is a large genus of flowering plants in the family Brassicaceae, commonly known as whitlow-grasses (though they are not related to the true grasses). Species There are over 400 species: *''Draba abajoensis'' Windham & Al-Shehbaz *''Dr ...

'' (whitlow-grasses) * ''

Armeria ''Armeria'' is a genus of flowering plants. These plants are sometimes known as "lady's cushion", "thrift", or "sea pink" (the latter because as they are often found on coastlines). The genus counts over a hundred species, mostly native to the ...

villosa''

References

{{Reflist Biological concepts Biology terminology Botanical nomenclature Plant taxonomy Species Zoological nomenclature