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Gene pool

The gene pool is the total genetic information possessed by the reproductive members of a population, encompassing all genes and their variant forms known as alleles at every genetic locus within an interbreeding group of a single species.^[1] The concept originated with Russian geneticist A. S. Serebrovsky's "genofond" in the 1920s and was introduced in English by Theodosius Dobzhansky in his 1937 book Genetics and the Origin of Species, where he defined evolution as "a change in the frequency of an allele within a gene pool." It serves as the foundational reservoir of hereditary variation that defines a population's potential for inheritance and adaptation.^[1] In population genetics, the gene pool is analyzed through allele frequencies, which quantify the relative proportions of different alleles for each gene across the population, providing a snapshot of its genetic structure.^[2] These frequencies remain stable under idealized conditions of infinite population size, random mating, and absence of external influences, as described by the Hardy–Weinberg equilibrium; however, real-world deviations drive evolutionary change.^[3] The gene pool's genetic diversity, arising from polymorphisms at multiple loci, is essential for buffering populations against environmental stresses, diseases, and demographic fluctuations, thereby enhancing long-term viability.^[1] Changes in the gene pool over generations, driven by mechanisms such as mutation, natural selection, genetic drift, and gene flow, underlie evolution and have applications in fields like conservation biology.^[3]

Definition and Fundamentals

Core Definition

A gene pool is defined as the complete set of unique alleles and genes present within an interbreeding population of a species at a given time.^[4] This encompasses all genetic variants that can be passed on through reproduction, forming the reservoir from which offspring inherit their traits.^[5] Gene pools represent the total genetic variation available for inheritance and natural selection within a population, enabling adaptation to environmental pressures over generations.^[4] Unlike the genome, which constitutes the entire set of DNA instructions in a single individual organism—such as the 23 pairs of chromosomes in human cells plus mitochondrial DNA—the gene pool aggregates this genetic material across multiple individuals in a breeding group.^[6] In contrast, a metagenome refers to the collective nucleotide sequences from all organisms in an environmental sample, typically microbial communities, rather than the bounded variation of one interbreeding population.^[7] The boundaries of a gene pool are species-specific, determined by the potential for genetic exchange among individuals. In bacterial populations, the gene pool can include alleles shared through mechanisms such as conjugation and transformation, though horizontal gene transfer can occasionally extend variation beyond strict species lines. In mammalian species, the gene pool is more rigidly confined to interbreeding groups via sexual reproduction, preserving distinct genetic lineages within the species.

Importance in Populations

A large gene pool provides populations with greater adaptability to environmental changes by offering a wider array of genetic variants that can confer survival advantages under varying conditions, such as shifts in climate or habitat alterations.^[8] This diversity enhances disease resistance, as multiple alleles can evolve to counter pathogens, reducing the likelihood of widespread susceptibility to infections.^[9] Furthermore, a robust gene pool supports evolutionary potential by supplying raw material for natural selection, enabling populations to respond to selective pressures over generations and avoid stagnation in fitness.^[10] In contrast, small gene pools lead to increased homozygosity, where individuals are more likely to inherit identical alleles from both parents, amplifying the expression of deleterious recessive traits.^[11] This results in inbreeding depression, manifesting as reduced fitness, including lower reproductive success and weakened immune responses.^[12] Genetic drift becomes more pronounced in small populations, randomly altering allele frequencies and accelerating the loss of beneficial variants, which heightens the overall extinction risk by limiting adaptive capacity.^[13] The cheetah (Acinonyx jubatus) exemplifies the perils of a diminished gene pool; its severe historical bottleneck has resulted in extremely low genetic diversity, contributing to inbreeding depression and fertility issues such as poor semen quality and high rates of sperm abnormalities.^[14]^[15] Similarly, the northern elephant seal (Mirounga angustirostris) underwent a drastic population bottleneck in the 19th century, reducing its genetic variation to near undetectable levels and illustrating how such events can constrain long-term population viability despite numerical recovery.^[16]^[17] The concept of effective population size (N_e) serves as a key qualitative indicator of gene pool robustness, representing the number of breeding individuals that contribute to the next generation and determining the rate of genetic drift and inbreeding; smaller N_e values exacerbate vulnerabilities even in census populations that appear large.^[18] Quantitative assessments of diversity, such as heterozygosity indices, can further highlight these dynamics but are explored in detail elsewhere.^[19]

Measures of Genetic Diversity

Genetic diversity within a gene pool is quantified using several key metrics that capture variation at the allelic and genotypic levels. Allele richness refers to the number of alleles present at a locus, standardized for sample size through rarefaction to enable comparisons across populations of unequal sizes.^[20] This metric highlights the raw allelic variation available, which is crucial for assessing a population's evolutionary potential, as higher richness indicates greater opportunities for adaptation.^[21] Heterozygosity measures the proportion of individuals that are heterozygous at a given locus and is divided into observed heterozygosity (Ho), which is the actual frequency of heterozygotes in a sample, and expected heterozygosity (He), which is the predicted frequency under Hardy-Weinberg equilibrium based on allele frequencies.^[20] The formula for expected heterozygosity is H_e = 1 - \sum p_i^2, where p_i is the frequency of the i-th allele at the locus.^[20] Observed heterozygosity is simply calculated as H_o = \frac{\text{number of heterozygotes}}{\text{total number of individuals}}.^[20] These metrics provide insight into the probability that two randomly selected alleles from the population are different, with He serving as a robust indicator of gene diversity less sensitive to sample size biases.^[20] Polymorphism rates, often expressed as the percentage of polymorphic loci (P), quantify the proportion of loci that exhibit more than one allele within a population, where a locus is typically considered polymorphic if the frequency of the most common allele is less than 0.99 or 0.95.^[22] This rate reflects the overall variability across multiple loci and is particularly useful for comparing genetic variation between populations or species.^[22] Another complementary metric is the Shannon diversity index (H'), which accounts for both the number of alleles and their evenness in frequency distribution, making it sensitive to rare alleles. The formula is H' = -\sum p_i \ln(p_i), where p_i is the frequency of the i-th allele.^[23] In population genetics, this index is applied to allelic data to provide a more nuanced measure of diversity than simple counts, though unbiased estimators like Zahl's jackknife method are recommended to correct for small sample biases.^[23] Various techniques have been developed to empirically measure these metrics, evolving from protein-based to genomic approaches. Allozyme analysis, introduced in the 1960s, uses electrophoresis to detect enzyme variants encoded by allelic differences, offering a cost-effective way to estimate heterozygosity and polymorphism at a limited number of loci (typically up to 30 per species).^[24] DNA sequencing techniques, such as those targeting microsatellites (short tandem repeats of 2-6 base pairs), amplify and size-variable regions via PCR to reveal length polymorphisms, enabling high-resolution assessment of genetic diversity in co-dominant markers.^[24] Single nucleotide polymorphisms (SNPs), identified through genotyping arrays or sequencing, provide abundant, stable markers for quantifying variation across the genome, with advantages in throughput and automation despite requiring prior sequence knowledge.^[24] Whole-genome sequencing (WGS), facilitated by next-generation platforms like Illumina or PacBio, delivers comprehensive data on all genetic variants, allowing precise calculation of metrics like He and allele richness at a population scale, though it remains resource-intensive.^[24] Interpretation of these measures is essential for evaluating gene pool health; for instance, expected heterozygosity values below 0.5 often signal a depleted gene pool due to bottlenecks or inbreeding, increasing vulnerability to environmental changes.^[25] In the critically endangered lake minnow (Rhynchocypris percnurus), microsatellite analyses revealed an average He of 0.36 across populations, indicating severely reduced diversity and highlighting the need for conservation interventions.^[25] Similarly, the white-headed langur (Trachypithecus leucocephalus) exhibits very low heterozygosity in its relict populations, attributed to historical isolation and small effective population sizes.^[26] These examples underscore how low metric values (<0.5 for He) correlate with elevated extinction risk in endangered species.^[26]

Historical Development

Origins of the Concept

The concept of the gene pool traces its intellectual roots to the mid-19th century, particularly Charles Darwin's emphasis on heritable variation within populations as the raw material for natural selection. In works such as On the Origin of Species (1859), Darwin described how differences among individuals in a population could lead to adaptive changes over generations, though he lacked a precise mechanism for inheritance beyond blending theories.^[27] This population-level perspective on variation and heredity laid foundational groundwork for later genetic interpretations, shifting attention from fixed species traits to dynamic collective differences.^[28] The explicit formulation of the gene pool emerged in the 1920s among Russian geneticists, who developed it amid intense debates on eugenics, human heredity, and the nascent field of population genetics. In the Soviet Union, where biology intersected with social and economic planning, the term "genofond" (gene fund) was introduced to denote the total reservoir of genetic material available within a population, treatable as a national resource akin to natural assets.^[29] This innovation marked a pivotal shift from the individual-centric focus of Mendelian genetics—which emphasized inheritance patterns in single organisms or crosses—to a holistic, population-oriented view that considered aggregate genetic diversity and its evolutionary implications.^[30] Russian eugenics circles, active through societies like the Russian Eugenics Society founded in 1920,^[31] further propelled this idea by applying it to human populations, though often entangled with ideological concerns over racial and social improvement.^[32] These early developments gained broader traction in the early 20th century through the Modern Synthesis, which unified Mendelian genetics with Darwinian evolution by framing populations as gene pools subject to forces like selection, mutation, and drift. This integration, crystallized in the 1930s and 1940s, positioned the gene pool as the central unit for tracking evolutionary change, resolving earlier tensions between particulate inheritance and continuous variation.^[33] By reconceptualizing evolution at the genetic population level, the Synthesis transformed the "genofond" idea into a cornerstone of modern evolutionary biology.^[34]

Key Contributors

The concept of the gene pool originated with Russian geneticist Alexander S. Serebrovsky in the 1920s, when he coined the term "genofond" (gene fund) to denote the total genetic material available within a population, with a particular focus on its utility as a resource for agricultural breeding and maintaining genetic diversity in livestock and crops. Serebrovsky's formulation emphasized the gene fund as a dynamic reservoir that could be harnessed to improve domesticated species, influencing early Soviet efforts in applied genetics and population studies.^[35]^[36] Theodosius Dobzhansky, a Ukrainian-American evolutionary biologist and student of Russian genetics, played a pivotal role in translating and popularizing the concept in English-speaking scientific communities. In his landmark 1937 book Genetics and the Origin of Species, Dobzhansky elaborated on the gene pool as the aggregate of genetic variants in a population, underscoring its central importance in processes like adaptation, natural selection, and speciation by illustrating how gene frequencies shift to drive evolutionary change. Dobzhansky first employed the exact English phrase "gene pool" in 1950, adapting Serebrovsky's "genofond" to describe the genetic composition of natural populations and reinforcing its relevance to understanding species boundaries.^[37]^[38] Nikolai I. Vavilov, a pioneering Russian botanist and geneticist, advanced the practical application of gene pool ideas to crop plants in the 1920s and 1930s through his extensive global expeditions to identify centers of origin and diversity. Vavilov's work treated regional crop gene pools as repositories of adaptive traits from wild progenitors and landraces, establishing the Institute of Plant Industry (now Vavilov Institute) as a major repository for conserving these genetic resources to support agriculture amid environmental challenges. Although Vavilov did not coin the term, his theories on crop evolution and variability directly informed later gene pool frameworks in plant breeding.^[39] Building on these foundations, American agronomist and botanist Jack R. Harlan, in collaboration with J. M. J. de Wet, provided a influential classification of crop gene pools in 1971 that categorized them into primary (closely related taxa fully interfertile with the crop), secondary (partially cross-compatible species requiring special techniques), and tertiary (distant relatives accessible only via advanced methods like embryo rescue). This system, outlined in their paper "Toward a Rational Classification of Cultivated Plants," offered a structured approach to accessing genetic diversity for breeding resilient varieties, profoundly shaping modern conservation and utilization strategies for crop genetic resources.^[40]

Applications

In Population Genetics

In population genetics, the gene pool serves as the foundational reservoir of genetic variation within a breeding population, where allele frequencies dictate the potential for evolutionary change. The Hardy-Weinberg equilibrium models an idealized scenario in which these frequencies remain stable from generation to generation, provided no evolutionary forces are at play. This principle, independently formulated by G. H. Hardy and Wilhelm Weinberg, posits that under conditions of infinite population size, random mating, and absence of mutation, migration, selection, or genetic drift, the proportions of genotypes will not deviate from expected values based on allele frequencies.^[41]^[42] For a single locus with two alleles denoted as p (frequency of allele A) and q (frequency of allele a, where p + q = 1), the equilibrium genotype frequencies are expressed as:

p^2 + 2pq + q^2 = 1

Here, p^2 represents the frequency of AA homozygotes, $2pq the frequency of Aa heterozygotes, and q^2 the frequency of aa homozygotes. This equation illustrates how the gene pool maintains genetic equilibrium through random segregation and recombination, serving as a null model to detect deviations indicative of evolutionary processes.^[41]^[43] Evolutionary forces disrupt this equilibrium by altering allele frequencies within the gene pool. Gene flow, driven by migration of individuals carrying different alleles between populations, tends to reduce genetic differentiation and increase homogeneity across gene pools by exchanging genetic material.^[44] Natural selection, in contrast, systematically shifts allele frequencies toward those conferring higher fitness in specific environments, thereby reshaping the gene pool to favor adaptive variants while potentially reducing overall diversity if selection is strong and directional.^[45] Such dynamics contribute to speciation when gene pools diverge sufficiently to establish reproductive isolation. Limited gene flow combined with differential natural selection can cause isolated populations to accumulate distinct alleles, leading to genetic incompatibility over time. Darwin's finches exemplify this process: ancestral populations on the Galápagos Islands, separated by geography, experienced divergent selection on beak morphology due to varying food resources, resulting in the radiation of at least 15 species with partitioned gene pools and minimal interbreeding.^[46]^[47]

In Breeding Programs

In breeding programs, the gene pool concept provides a framework for classifying crop relatives based on their potential for hybridization and genetic exchange, facilitating targeted incorporation of beneficial traits into cultivated varieties. Harlan and de Wet (1971) proposed a classification dividing the gene pool into primary (GP-1), secondary (GP-2), and tertiary (GP-3) categories. The primary gene pool (GP-1) encompasses the cultivated species and its conspecific wild forms, where crosses produce fertile hybrids with minimal barriers, allowing straightforward introgression of traits like yield enhancement. The secondary gene pool (GP-2) includes closely related species that yield partially fertile hybrids but may require overcoming partial sterility or chromosomal differences through techniques such as backcrossing. The tertiary gene pool (GP-3) involves more distant relatives, where hybridization demands advanced interventions like embryo rescue or colchicine treatment to bridge significant reproductive barriers and salvage viable progeny.^[48] This classification has been instrumental in widening crop gene pools to enhance resilience against environmental stresses, particularly in staple crops like wheat (Triticum spp.). Breeders have tapped wild relatives from secondary and tertiary gene pools to introduce drought resistance; for instance, alleles from Aegilops tauschii (a progenitor in the tertiary pool) have been incorporated into modern wheat cultivars to improve water-use efficiency and yield stability under arid conditions, as demonstrated in pre-breeding efforts that identified quantitative trait loci (QTLs) for root architecture and osmotic adjustment. Similarly, wild emmer wheat (Triticum dicoccoides, in the secondary pool) has contributed genes for drought tolerance, enabling the development of varieties that maintain productivity in rainfed systems across the Mediterranean and Middle East. These efforts underscore how accessing diverse gene pools counters the genetic bottlenecks from intensive domestication, boosting adaptability without compromising agronomic performance.^[49]^[50] In livestock breeding, gene pool management focuses on maintaining genetic diversity to mitigate inbreeding depression, which can reduce fertility, health, and productivity in confined populations. For cattle, artificial insemination (AI) programs strategically diversify the effective gene pool by disseminating semen from a broad array of sires, thereby increasing the number of contributing ancestors and slowing the accumulation of deleterious alleles. This approach has been critical in dairy breeds like Holsteins, where genomic evaluations guide sire selection to balance genetic gain for milk yield with inbreeding coefficients below 1% per generation, preventing losses in reproductive efficiency on the order of 0.5-1% per 1% increase in inbreeding.^[51] Cryopreservation of semen and embryos further expands access to historical gene pools, allowing reintroduction of lost diversity from foundation stocks.^[52] Modern breeding integrates molecular tools to efficiently tap wild and exotic gene pools, overcoming traditional hybridization challenges. Marker-assisted selection (MAS) enables precise tracking of target alleles from wild relatives during backcrossing, reducing linkage drag—the unwanted transfer of deleterious genes—and accelerating introgression by up to 50% compared to phenotypic selection alone. In crops such as rice and tomato, MAS has facilitated the transfer of resistance genes from tertiary gene pool species, enhancing traits like disease tolerance while preserving elite backgrounds. These genomic strategies, combined with high-throughput sequencing, allow breeders to mine untapped diversity systematically, ensuring sustainable genetic gains in the face of climate variability.^[53]^[54]

In Conservation Biology

In conservation biology, the gene pool of threatened species faces severe threats from habitat loss and overexploitation, which drastically reduce population sizes and lead to diminished genetic diversity through inbreeding and genetic drift.^[55] For instance, the Florida panther (Puma concolor coryi) experienced a severe contraction in range and numbers due to habitat fragmentation and historical hunting, resulting in one of the lowest levels of genetic variation among large carnivores, with high rates of congenital defects and low survival rates.^[56] These pressures not only erode adaptive potential but also increase extinction risk by limiting the population's ability to respond to environmental changes.^[57] To counteract these threats, conservation strategies emphasize maintaining and enhancing gene pools through captive breeding programs, which provide controlled environments to boost population numbers while minimizing loss of genetic variation via techniques like pedigree management and equal founder contributions.^[57] Gene banking complements this by cryopreserving genetic material such as seeds, embryos, and gametes in seed banks or genome resource banks, allowing long-term storage of diversity for future restoration efforts without ongoing live maintenance.^[58] Reintroduction programs then deploy these resources to wild habitats, aiming to reestablish viable populations; success depends on integrating genetic monitoring to avoid further erosion during the transition from captivity.^[59] The International Union for Conservation of Nature (IUCN) provides guidelines on minimum viable population (MVP) sizes to preserve gene pools, recommending short-term thresholds of around 50 individuals to avoid inbreeding depression and long-term targets of 500 or more to retain evolutionary potential, as refined in the updated 50/500 rule.^[60] Translocations, involving the movement of individuals between populations, are a key tactic to boost gene flow and counteract isolation, thereby increasing heterozygosity and adaptive capacity, though they require careful genetic matching to prevent outbreeding depression.^[61] These interventions have proven effective in cases like the genetic rescue of isolated populations, where introduced gene flow enhances fitness without overwhelming local adaptations.^[62] In the genomic era since the 2010s, CRISPR-Cas9 gene editing has emerged as a tool to address depleted gene pools by precisely inserting beneficial alleles or correcting deleterious mutations, potentially restoring lost diversity in small populations.^[63] Such applications, while promising, are guided by ethical frameworks to ensure they support rather than supplant natural evolutionary processes.^[64]

Centers of Diversity

Vavilov's Centers

Nikolai Vavilov, a pioneering Russian botanist and geneticist, conducted extensive expeditions across five continents during the 1920s and 1930s to collect plant specimens and map regions of high genetic diversity in crop species.^[65] These journeys, spanning over 64 countries, amassed more than 200,000 seed samples, which he used to identify geographic hotspots where cultivated plants exhibited the greatest variation in traits, indicating their likely origins.^[66] Vavilov's fieldwork emphasized mountainous and highland areas, where he observed that long-term human agricultural practices had concentrated diverse alleles and wild progenitors, fostering the domestication of numerous staple crops.^[67] Central to Vavilov's theory was the concept of primary centers of origin, defined as regions where crop species first evolved from wild ancestors due to prolonged selection pressures from indigenous farming communities.^[68] He proposed eight such primary centers, each associated with a unique suite of domesticated plants, and two secondary centers where diversity radiated from primaries through migration and adaptation.^[69] The primary centers include: Chinese (e.g., rice, soybeans, and millet); Indian (e.g., rice, sugarcane, eggplant, bananas, coconut, and breadfruit); Central Asiatic (e.g., wheat, apples, and carrots); Near Eastern (e.g., wheat, barley, and peas); Mediterranean (e.g., olives, grapes, and figs); Abyssinian (Ethiopian) (e.g., sorghum, teff, and coffee); Mesoamerican (South Mexican and Central American) (e.g., maize, beans, and squash); and South American (Andean) (e.g., potatoes, quinoa, and tomatoes).^[68] The secondary centers, such as European and North American, showed derived diversity but lower primitive forms.^[69] This model posited that these centers served as gene pools rich in adaptive variation, essential for breeding resilient varieties against environmental stresses.^[67] Illustrative examples from Vavilov's centers highlight their role in crop evolution. In the Mesoamerican center, maize (Zea mays) displays extraordinary morphological diversity, from pod corn to floury types, tracing back to teosinte progenitors domesticated around 9,000 years ago.^[70] Similarly, the Abyssinian center is a hotspot for sorghum (Sorghum bicolor), with hundreds of landraces varying in grain color, plant height, and drought tolerance, alongside coffee (Coffea arabica), which originated in Ethiopian highlands and exhibits genetic clusters tied to wild forest populations.^[68] These regions underscore how localized human cultivation amplified allelic diversity, creating reservoirs of traits like disease resistance and yield potential.^[67] Vavilov's framework profoundly influenced global efforts to preserve crop gene pools, serving as the foundation for systematic seed collection by institutions such as the United States Department of Agriculture (USDA), which initiated missions to Vavilov-identified regions starting in the 1940s. It also inspired the Consultative Group on International Agricultural Research (CGIAR), whose genebanks in centers like those in Mexico and Ethiopia continue to draw from these hotspots to support breeding programs for food security.^[71] By emphasizing the urgency of conserving diversity in origin centers, Vavilov's legacy has guided international conservation strategies, preventing erosion of genetic resources amid modern agricultural intensification.^[72]

Modern Perspectives

Post-2000 genomic studies have significantly refined the understanding of gene pool centers through phylogeographic mapping and DNA barcoding techniques, revealing a more complex distribution of crop diversity than originally proposed by Vavilov. These approaches, leveraging high-density SNP arrays and chloroplast DNA markers, have identified multiple domestication events and expansions, expanding the recognized number of diversity hotspots to over 12, with some analyses delineating up to 19 regions based on crop wild relative distributions from global biodiversity databases.^[73] For instance, phylogeographic analysis of wheat landraces across 105 countries has confirmed the Fertile Crescent as the primary center while highlighting secondary differentiation poles in the Mediterranean and Central Asia, aligned with ancient human migration routes.^[74] DNA barcoding has further enabled precise delimitation of genetic variation in crops like potatoes, uncovering chlorotypes and introgressions from wild species that indicate additional micro-centers of diversity. Climate change poses substantial threats to these gene pool centers, driving shifts in distribution and erosion of genetic diversity, particularly in vulnerable regions such as the Mediterranean Basin. Projections indicate severe reductions in suitable habitats for crop wild relatives, with the Western Mediterranean hotspot facing dramatic losses in genetic variation due to altered temperature and precipitation patterns.^[75] Species distribution modeling for 1,261 crop wild relative taxa across 167 genepools forecasts range contractions of up to 50% or more under future scenarios, necessitating targeted in situ conservation to preserve shifting centers.^[76] These impacts underscore the urgency of integrating climate projections into gene pool management to mitigate diversity loss in biodiversity hotspots. Global databases like GenBank and initiatives such as the Crop Wild Relatives Project have become essential for tracking and safeguarding gene pools. GenBank's repository of nucleotide sequences supports phylogeographic analyses by providing vast genomic data for identifying underexplored diversity hotspots. The Crop Wild Relatives Project, in collaboration with genebanks worldwide, has collected nearly 5,000 seed samples from underrepresented genepools as of 2021, enhancing pre-breeding efforts and conservation strategies through integrated databases that map geographic and genetic distributions.^[77] Recent efforts, including the project's second phase launched in 2022, continue to expand collections and prioritize climate-resilient traits in crop wild relatives.^[78] In human genetics, modern genomic perspectives apply similar principles to trace ancient gene pool migrations, with the Out-of-Africa model illustrating how dispersals shaped global diversity. Whole-genome sequencing of diverse populations confirms a severe bottleneck during the initial exodus from Africa around 60,000 years ago, followed by regional adaptations that enriched peripheral gene pools.^[79] Recent studies further reveal multiple waves of migration and back-migrations, refining the model's timeline and highlighting gene flow dynamics that parallel crop phylogeography.^[80]

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The methods of formal taxonomy have not been very satisfactory for the classification of cultivated plants. As a result, the people who deal with cultivated ...
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The Hardy-Weinberg equation describes expectations about the gene pool of a population that isn't evolving, that is large, mates randomly, doesn't experience ...
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There is variation among individuals within a population in some trait. This variation is heritable (i.e., there is a genetic basis to the variation, such ...
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Jul 22, 2015 · A recent analysis of the genomes of Darwin's finches revealed extensive interspecies allele sharing throughout the history of the radiation.
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I. R. Harlan and I. M. I. de Wet. Summary. The methods of formal taxonomy have not been very satisfactory for the classification of cultivated plants. As a ...
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The harnessing of WWR genetic resources presents a viable pathway to developing high-yielding, resilient crops that sustain future food supplies. Achieving this ...
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Potential of Wild Relatives of Wheat: Ideal Genetic Resources for ...
The close relatives of domesticated wheats represent an ideal gene pool for the use of breeders. The genera Aegilops and Triticum are known as the main gene ...
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In this paper, we discuss the role of genetic selection in high-yielding dairy breeding schemes and potential routes toward the development of more sustainable ...
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Exploiting Wild Relatives for Genomics-assisted Breeding of ...
Marker-assisted selection (MAS) can increase the efficiency of incorporating desirable traits present in wild germplasm into domesticated, or elite, cultivars.Missing: tapping | Show results with:tapping
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In this review, we have discussed the positive aspects of molecular marker-assisted selection and its precise applications in plant breeding programmes.
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Genetics and conservation biology - ScienceDirect.com
The primary factors contributing to extinction are habitat loss, introduced species, over exploitation and pollution. These factors are caused by humans, and ...Missing: pool | Show results with:pool
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The consequences of demographic reduction and genetic depletion ...
The Florida panther has recently suffered severe range and demographic contraction, leaving a remarkably low level of genetic diversity.<|separator|>
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How well can captive breeding programs conserve biodiversity? A ...
Captive breeding programs are increasingly being initiated to prevent the imminent extinction of endangered species and/or populations.
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Strategies for establishing and using genome resource banks to ...
Oct 7, 2022 · Here we present basic guidelines, focusing on strategies for the collection, maintenance, and use of semen GRBs for protecting genetic diversity.
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[PDF] Demographic and Genetic Management of Captive Populations
Successful reintroduction of captive born individuals back into the wild to re-establish natural free-ranging populations of golden lion tamarins ( ...
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Revised recommendations for the 50/500 rules, Red List criteria and ...
Minimum viable population (MVP) sizes required for long-term population persistence are commonly determined using population viability analysis (PVA) ...Missing: pool | Show results with:pool
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Jun 18, 2011 · We provide a classification of translocations based on specific genetic goals for both threatened species and ecological restoration.
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Dec 20, 2021 · Restored Gene Flow and Genetic Mixing Can Overcome Low Population Performance. Gene flow is an evolutionary force that may both aid and ...Applied Conservation... · Restored Gene Flow And... · Genomic Inference On...
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The current status of the use of genetic modification and editing to ...
Oct 25, 2024 · This review highlights the current use of GME technologies in biodiversity, ecological integrity, and wildlife conservation for protecting a species' genetic ...
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Building coral reef resilience through assisted evolution - PNAS
Mixing gene pools from the same or different, closely related species can lead to offspring with novel genotypes producing novel phenotypes. A range of coral ...
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[PDF] Transforming ecology and conservation biology through genome ...
The principle of CRISPR genetic barcoding is to use genome editing technology to introduce unique DNA mutations (e.g., substitutions or small insertions or ...
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The Tragedy of the World's First Seed Bank | Science History Institute
Sep 27, 2022 · Vavilov leapt into action and in the 1920s began collecting and storing in Leningrad as many seeds, grains, fruits, nuts, and tubers as he could ...
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Nikolai Ivanovich Vavilov: Plant Geographer, Geneticist, Martyr of ...
His efforts established the Soviet Union as a world leader in genetics and plant breeding in the 1920s and early 1930s. Vavilov carried out an extensive series ...
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The Impact of Vavilov's Concept of the Centres of Crop Origin ... - NIH
Jul 19, 2023 · The main regularity determining the diversity of a Linnaean species has been referred to by Vavilov as the law of homologous series in ( ...
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Vavilovian Centers of Plant Diversity: Implications and Impacts in
East Asian center includes central and western China, Korea, Japan, and Taiwan. This is the native region for soybeans, millet, many vegetable crops, and ...
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The Origins of Crop Plants – History and Science of Cultivated Plants
In the 1920s, Nikolai Vavilov established the world's first seed bank in the building of the Bureau of Applied Botany in Leningrad, housing major collections of ...
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23.2: The Origins of Crop Plants - Biology LibreTexts
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Nikolai Vavilov: The Father of Genebanks - Crop Trust
Jan 10, 2024 · Best known for his work on identifying centers of crop origin and diversity, Vavilov traveled to regions where the cousins of cultivated plants ...Missing: pools 1920s
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Envisaging an Effective Global Long-Term Agrobiodiversity ...
1. Introduction. When Nikolai Vavilov began to collect seeds from around the world in the 1920s and 1930s, he was a pioneer in what has now come to ...
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Aug 15, 2025 · We then identified the center of origin for each crop, covering seven of Vavilov's eight centers of plant origins37 and 12 of the 19 center-of- ...
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May 29, 2019 · We report on a worldwide phylogeographical study aiming at understanding this complex history of wheat dissemination and differentiation.
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Dramatic impact of future climate change on the genetic diversity ...
The Western Mediterranean Basin constitutes one of the hotspots of biodiversity where the effects of climate change are expected to be more dramatic.
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Modeling of crop wild relative species identifies areas globally for in ...
Apr 23, 2019 · Here we apply species distribution modelling, climate change projections and geographic analyses to 1261 CWR species from 167 major crop genepools to explore ...
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Crop Wild Relatives Project Delivers Beyond Expectation
By harnessing the diversity conserved in genebanks, we can work together with farmers, scientists and plant breeders to develop new, more resilient crop ...
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Human Dispersal Out of Africa: A Lasting Debate - PMC
Under all of these models, genetic evidence suggests that migration out of Africa was accompanied by a severe bottleneck in the initial migrating group(s) ...
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Genetic studies reveal diversity of early human populations
These observations support the “Out of Africa” model; the ... genetic bottleneck caused by the migration out of Africa occurred roughly 60,000 years ago.