Putting the Biological Species Concept to the Test: Using Mating Networks to Delimit Species

Mosquito-borne arboviruses, including a diverse array of alphaviruses and flaviviruses, lead to hundreds of millions of human infections each year. Current methods for species-level classification of arboviruses adhere to guidelines prescribed by the International Committee on Taxonomy of Viruses (ICTV), and generally apply a polyphasic approach that might include information about viral vectors, hosts, geographical distribution, antigenicity, levels of DNA similarity, disease association and/or ecological characteristics. However, there is substantial variation in the criteria used to define viral species, which can lead to the establishment of artificial boundaries between species and inconsistencies when inferring their relatedness, variation and evolutionary history. In this study, we apply a single, uniform principle – that underlying the Biological Species Concept (BSC) – to define biological species of arboviruses based on recombination between genomes. Given that few recombination events have been documented in arboviruses, we investigate the incidence of recombination within and among major arboviral groups using an approach based on the ratio of homoplastic sites (recombinant alleles) to non-homoplastic sites (vertically transmitted alleles). This approach supports many ICTV-designations but also recognizes several cases in which a named species comprises multiple biological species. These findings demonstrate that this metric may be applied to all lifeforms, including viruses, and lead to more consistent and accurate delineation of viral species.

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Fern nothogenera and ×Lepinema, a new hybrid genus between Ellipinema and Lepisorus (Polypodiaceae)

Phytotaxa ◽

10.11646/phytotaxa.455.4.3 ◽

2020 ◽

Vol 455 (4) ◽

pp. 262-266

Author(s):

LIANG ZHANG ◽

LI-BING ZHANG

Keyword(s):

Species Concept ◽

Intergeneric Hybrid ◽

Molecular Data ◽

Biological Species ◽

Biological Species Concept

The biological species concept is not exclusively applicable in many groups of organisms including ferns. Interspecific fern hybrids are not rare: there are 16 intergeneric hybrid genera in ferns confirmed with molecular data. Here we add one more hybrid genus in the tribe Lepisoreae of Polypodiaceae, ×Lepinema, formed via hybridization between parents in two genera: Ellipinema and Lepisorus.

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The increasing multiplicity of the species concepts

BSGF - Earth Sciences Bulletin ◽

10.2113/176.2.221 ◽

2005 ◽

Vol 176 (2) ◽

pp. 221-225

Author(s):

Jean Génermont

Keyword(s):

Species Concept ◽

Cladistic Analysis ◽

Biological Species ◽

Point Of View ◽

Biological Species Concept ◽

Phylogenetic Species ◽

Phylogenetic Species Concept ◽

Ecological Criteria ◽

Stem Species ◽

Definition Of

Abstract In 1980, Henri Tintant advocated the usefulness of the biological species concept in paleontology. At this time, this concept was still accepted by many neontologists, but it was already rather severely criticized by some others. In fact, a lot of new concepts appeared in the course of the following two decades. While a few ones are mere adjustments of the biological concept, for instance taking in account ecological criteria, in such a way that it could be applied to clonal organisms, some others, which were developed in connexion with the cladistic theory of taxonomy, are truly new from a conceptual point of view. The diagnosable version of the phylogenetic species concept is somewhat reminiscent of Simpson’s evolutionary species concept, since it accepts phyletic speciation as well as survival of the stem species after a cladogenetic event. One of its more criticizable features, from a cladistic point of view, is that the species are not necessarilly monophyletic. On another hand, according to the monophyly version of the phylogenetic species concept, species are recognized rather subjectively as monophyletic taxa revealed by some previous cladistic analysis dealing with operational taxonomic units. A consensus on the definition of species cannot be expected, since all concepts related to the biological one are founded on population grouping on the basis of potentially identical evolutionary fates, while those which are related to cladistic taxonomy are exclusively concerned with historical features.

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Charles Darwin's biological species concept and theory of geographic speciation: the transmutation notebooks

Annals of Science ◽

10.1080/00033797800200251 ◽

1978 ◽

Vol 35 (3) ◽

pp. 275-297 ◽

Cited By ~ 34

Author(s):

Malcolm J. Kottler

Keyword(s):

Species Concept ◽

Biological Species ◽

Biological Species Concept

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Group selection and the development of the biological species concept

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2010.0040 ◽

2010 ◽

Vol 365 (1547) ◽

pp. 1853-1863 ◽

Cited By ~ 8

Author(s):

James Mallet

Keyword(s):

Species Concept ◽

Biological Species ◽

Second World War ◽

Species Level ◽

Biological Species Concept ◽

Ernst Mayr ◽

World War ◽

Mutualistic Interaction ◽

Theodosius Dobzhansky ◽

Second World

The development of what became known as the biological species concept began with a paper by Theodosius Dobzhansky in 1935, and was amplified by a mutualistic interaction between Dobzhansky, Alfred Emerson and Ernst Mayr after the second world war. By the 1950s and early 1960s, these authors had developed an influential concept of species as coadapted genetic complexes at equilibrium. At this time many features of species were seen as group advantages maintained by selection to avoid breakdown of beneficial coadaptation and the ‘gene pool’. Speciation thus seemed difficult. It seemed to require, more so than today, an external deus ex machina , such as allopatry or the founder effect, rather than ordinary within-species processes of natural selection, sexual selection, drift and gene flow. In the mid-1960s, the distinctions between group and individual selection were clarified. Dobzhansky and Mayr both understood the implications, but their views on species changed little. These group selectionist ideas now seem peculiar, and are becoming distinctly less popular today. Few vestiges of group selectionism and species-level adaptationism remain in recent reviews of speciation. One wonders how many of our own cherished views on evolution will seem as odd to future biologists.

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Collembola, the biological species concept and the underestimation of global species richness

Molecular Ecology ◽

10.1111/mec.12472 ◽

2013 ◽

Vol 22 (21) ◽

pp. 5382-5396 ◽

Cited By ~ 38

Author(s):

Francesco Cicconardi ◽

Pietro P. Fanciulli ◽

Brent C. Emerson

Keyword(s):

Species Richness ◽

Species Concept ◽

Biological Species ◽

Biological Species Concept

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Predictors of Taxonomic Inflation and its Role in Primate Conservation

10.1101/2021.09.10.459781 ◽

2021 ◽

Author(s):

Maria J.A. Creighton ◽

Alice Q. Luo ◽

Simon M. Reader ◽

Arne Ø. Mooers

Keyword(s):

Perceived Risk ◽

Species Concept ◽

Research Effort ◽

Biological Species ◽

Primate Species ◽

Biological Species Concept ◽

Primate Conservation ◽

Phylogenetic Species Concept ◽

Initial Application ◽

Positive Message

ABSTRACTSpecies are the main unit used to measure biodiversity, but different preferred diagnostic criteria can lead to very different delineations. For instance, named primate species have more than doubled since 1982. Such increases have been termed “taxonomic inflation” and have been attributed to the widespread adoption of the ‘phylogenetic species concept’ (PSC) in preference to the previously popular ‘biological species concept’ (BSC). Criticisms of the PSC have suggested taxonomic inflation may be biased toward particular taxa and have unfavourable consequences for conservation. Here, we explore predictors of taxonomic inflation across primate taxa since the initial application of the PSC nearly 40 years ago. We do not find evidence that diversification rate, the rate of lineage formation over evolutionary time, is linked to inflation, contrary to expectations if the PSC identifies incipient species. We also do not find evidence of research effort in fields where work has been suggested to motivate splitting being associated with increases in species numbers among genera. To test the suggestion that splitting groups is likely to increase their perceived risk of extinction, we test whether genera that have undergone more splitting have also observed a greater increase in their proportion of threatened species since the introduction of the PSC. We find no cohesive signal of inflation leading to higher threat probabilities across primate genera. Overall, this analysis sends a positive message that threat statuses of primate species are not being overwhelmingly affected by splitting in line with what has recently been reported for birds. Regardless, we echo warnings that it is unwise for conservation to be reliant on taxonomic stability. Species (however defined) are not independent from one another, thus, monitoring and managing them as such may not meet the overarching goal of conserving biodiversity.

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Species limits in Pteruthius (Aves: Corvida) shrike-babblers: a comparison between the Biological and Phylogenetic Species Concepts

Zootaxa ◽

10.11646/zootaxa.2301.1.2 ◽

2009 ◽

Vol 2301 (1) ◽

pp. 29-54 ◽

Cited By ~ 4

Author(s):

FRANK E. RHEINDT ◽

JAMES A. EATON

Keyword(s):

Species Concept ◽

Molecular Data ◽

Biological Species ◽

Species Concepts ◽

Biological Species Concept ◽

Phylogenetic Species ◽

Species Status ◽

Phylogenetic Species Concept ◽

Sampling Regime ◽

Morphological And Molecular Data

The question of how to define a species continues to divide biologists. Meanwhile, the application of different species concepts has led to disparate taxonomic treatments that confound conservationists and other biologists. The most widely followed guidelines to species designation in avian and other vertebrate taxonomy are Ernst Mayr’s Biological Species Concept (BSC) and Joel Cracraft’s version of the Phylogenetic Species Concept (PSC). Although the BSC is considered to be more conservative in its assignment of species status, there is a lack of research demonstrating differences in taxonomic treatment between the BSC and the PSC with reference to a multi-taxon multi-trait study system. We examined the case of five traditionally recognized species of shrike-babbler (Pteruthius) that have recently been divided into 19 species under the PSC. Re-analyzing previous morphological and molecular data and adding new vocal data, we propose a BSC classification of 9 species. However, taking into consideration geographic gaps in the sampling regime, we contend that additional data will likely reduce discrepancies between the total numbers of species designated under the PSC and BSC. The current PSC species total is a likely overestimate owing to species diagnosis based on characters that erroneously appear to be unique to a taxon at low sample size. The current BSC species total as here proposed is a likely underestimate on account of the conservative designation of taxa as subspecies in equivocal cases, e.g. where BSC species status is potentially warranted but may be masked by insufficient data.

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Species and speciation.

10.1079/9781789249514.0004 ◽

2022 ◽

pp. 7-8

Author(s):

Richard A. I. Drew ◽

Meredith C. Romig

Keyword(s):

New Species ◽

Natural Selection ◽

Dna Sequences ◽

Species Concept ◽

Natural Habitat ◽

Biological Species ◽

Biological Species Concept ◽

Similar Species ◽

Host Fruit ◽

Morphological Species

Abstract This chapter discusses two species models, which are diametrically opposed. The first, often called the 'biological species concept', defines species in terms of 'reproductive isolation', convinced that species arise when subsets of a population are split off and remain geographically isolated over evolutionary time. If and when such new species are reunited with their founder population, interbreeding does not occur, or if it does, infertile progeny result. Hence, from the biological species concept, natural selection is a primary agent of change and directly selects for new species. In this sense, species are the direct products of natural selection and they are therefore 'adaptive devices'. When applying this species concept, it has been impossible to separate some sibling species of fruit flies in the genus Bactrocera where distinct morphological species can be similar in molecular analyses of certain DNA sequences, while similar species morphologically are distinct in the same molecular characters. A radically different model, the 'recognition concept of species', relies heavily on a knowledge of species ecology and behaviour, particularly in their natural habitat. The principal points in this concept are given. In contrast to the now-outdated biological species concept that leads one to depend on laboratory-based research to define species, the recognition concept requires workers to undertake extensive field research in the habitat of the taxon under investigation. In translating this approach to research in the insect family Tephritidae, particularly the Dacinae, some 35 years of field surveys have been undertaken throughout the Indian subcontinent, South-east Asia and the South Pacific region. These surveys included trapping using male lure traps and host fruit collections of commercial/edible fruits. The results of this work have included the provision of specimens of almost all known species for morphological descriptions (c.800 species), material for male pheromone chemistry, and data on host fruit relationships and biogeographical studies.

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Species limits and taxonomy in birds

The Auk ◽

10.1093/ornithology/ukab017 ◽

2021 ◽

Author(s):

Kevin Winker ◽

Pamela C Rasmussen

Keyword(s):

Case Studies ◽

Species Delimitation ◽

Population Genomics ◽

Species Concept ◽

Biological Species ◽

Integrative Approach ◽

Population Divergence ◽

Biological Species Concept ◽

Species Limits ◽

American Kestrel

Abstract Despite the acknowledged importance of defining avian species limits to scientific research, conservation, and management, in practice, they often remain contentious. This is true even among practitioners of a single species concept and is inevitable owing to the continuous nature of the speciation process, our incomplete and changing understanding of individual cases, and differing interpretations of available data. This issue of Ornithology brings together several papers on species limits, some more theoretical and general, and others case studies of specific taxa. These are viewed primarily through the lens of the biological species concept (BSC), by far the most widely adopted species concept in influential ornithological works. The more conceptual contributions focus on the importance of the integrative approach in species delimitation; the importance of considering selection with the increasing use of genomic data; examinations of the effectiveness of the Tobias et al. character-scoring species limits criteria; a review of thorny issues in species delimitation using examples from Australo-Papuan birds; and a review of the process of speciation that addresses how population divergence poses challenges. Case studies include population genomics of the American Kestrel (Falco sparverius); an integrative taxonomic analysis of Graceful Prinia (Prinia gracilis) that suggests two species are involved; and a reevaluation of species limits in Caribbean Sharp-shinned Hawk (Accipiter striatus) taxa.

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