An example is the ABO blood type antigens in humans, where three alleles govern the phenotype. In the absence of natural selection to preserve such a trait, it becomes more variable and deteriorate over time, possibly resulting in a vestigial manifestation of the trait, also called evolutionary baggage. Established traits are not immutable; traits that have high fitness in one environmental context may be much less fit if environmental conditions change. Natural selection had the power, according to Stephen Jay Gould, to "dethrone some of the deepest and most traditional comforts of Western thought", such as the belief that humans have a special place in the world. Define natural. (heritable) basis of any phenotype that gives that phenotype a reproductive advantage may become more common in a population. Modern evolutionary theory defines fitness not by how long an organism lives, but by how successful it is at reproducing. Ferner gilt es zu beachten, dass der Grundsatz der Rechtsfähigkeit nicht bedeutet, dass jedermann jede Art von Rechten haben kann. In other words, natural selection is a key process in the evolution of a population. Eines der wichtigsten Ziele dieses Gesetzes ist eine erleichterte Vornahme von Handlungen und Maßnahmen zur... Inwieweit sich ein Vertragshändler darauf berufen kann, dass Auskünfte über Kunden gegen die DSGVO verstoßen, ist Gegenstand einer Gerichtsentscheidung. Eine solche Teilrechtsfähigkeit hat beispielsweise der Nasciturus inne (vgl. Doch dieser weigerte sich zu... Karlsruhe (jur). Vertragspartner GmbH und natürliche Person. This occurs partly because random mutations arise in the genome of an individual organism, and their offspring can inherit such mutations. Die Rechtsfähigkeit endet mit dem Tod (Ableitung aus § 1922 Absatz 1 BGB). [23] Darwin published a detailed account of his evidence and conclusions in On the Origin of Species in 1859. On the other hand, "improvement in fitness" is not dependent on the differential survival and reproduction of individuals due to differences in phenotype, it is dependent on the absolute survival of the particular variant. [103] However, after a period with no new mutations, the genetic variation at these sites is eliminated due to genetic drift. Typically, r-selected species exploit empty niches, and produce many offspring, each with a relatively low probability of surviving to adulthood. dazu §§ 21 ff. He described natural selection as analogous to artificial selection, a process by which animals and plants with traits considered desirable by human breeders are systematically favoured for reproduction. The concept, published by Darwin and Alfred Russel Wallace in a joint presentation of papers in 1858, was elaborated in Darwin's influential 1859 book On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life. In the past, most changes in the genetic material were considered neutral or close to neutral because they occurred in noncoding DNA or resulted in a synonymous substitution. Die Definition des Begriffs “personenbezogene Daten” gleicht sich entsprechend. Im Prozessrecht entspricht die Rechtsfähigkeit der Parteifähigkeit. BGB). A variation in one of the many genes that contributes to a trait may have only a small effect on the phenotype; together, these genes can produce a continuum of possible phenotypic values.[102]. Over time, this process can result in populations that specialise for particular ecological niches (microevolution) and may eventually result in speciation (the emergence of new species, macroevolution). Stabilizing selection conserves functional genetic features, such as protein-coding genes or regulatory sequences, over time by selective pressure against deleterious variants. [29] However, some thinkers enthusiastically embraced natural selection; after reading Darwin, Herbert Spencer introduced the phrase survival of the fittest, which became a popular summary of the theory. There is an ongoing debate over the degree to which group selection occurs in nature. [26], For Darwin and his contemporaries, natural selection was in essence synonymous with evolution by natural selection. [20] When Darwin read Malthus in 1838 he was already primed by his work as a naturalist to appreciate the "struggle for existence" in nature. Natürliche Person als Rechnungsempfänger? NV-Art 02 A. Bescheinigung des Finanzamts über steuerliche Zuordnung einer Körperschaft. However, the theory of uniformitarianism in geology promoted the idea that simple, weak forces could act continuously over long periods of time to produce radical changes in the Earth's landscape. Individual selection acts on the individual, in the sense that adaptations are "for" the benefit of the individual, and result from selection among individuals. Diese tritt grundsätzlich mit dem Eintritt in die Volljährigkeit ein (vgl. Gene selection acts directly at the level of the gene. BGB [Bürgerliches Gesetzbuch] geregelt und von der juristischen Person zu unterscheiden (vgl. Neurodermitis* (atopisches Ekzem / atopische Dermatitis) ist eine nicht ansteckende Hauterkrankung und zählt zu den drei Erkrankungen des atopischen Formenkreises, zu dem auch Asthma bronchiale und Heuschnupfen (allergische Rhinitis) gehörten. [24], Darwin thought of natural selection by analogy to how farmers select crops or livestock for breeding, which he called "artificial selection"; in his early manuscripts he referred to a "Nature" which would do the selection. Darwin's ideas were inspired by the observations that he had made on the second voyage of HMS Beagle (1831–1836), and by the work of a political economist, Thomas Robert Malthus, who, in An Essay on the Principle of Population (1798), noted that population (if unchecked) increases exponentially, whereas the food supply grows only arithmetically; thus, inevitable limitations of resources would have demographic implications, leading to a "struggle for existence". [129], In 1922, Alfred J. Lotka proposed that natural selection might be understood as a physical principle that could be described in terms of the use of energy by a system,[130][131] a concept later developed by Howard T. Odum as the maximum power principle in thermodynamics, whereby evolutionary systems with selective advantage maximise the rate of useful energy transformation. "Survival of the fittest" does not give an "improvement in fitness", it only represents the removal of the less fit variants from a population. [68][69], Competition is modelled by r/K selection theory, which is based on Robert MacArthur and E. O. Wilson's work on island biogeography. Darin liegt ein wesentlicher Unterschied zum Recht der Bundesrepublik Deutschland und der Europäischen Union sowie zur hier verwendeten Definition, die sich am deutschen Recht orientiert. Sewall Wright elucidated the nature of selection and adaptation. But if variations useful to any organic being do occur, assuredly individuals thus characterised will have the best chance of being preserved in the struggle for life; and from the strong principle of inheritance they will tend to produce offspring similarly characterised. Die juristische Person ist Träger von Rechten und Pflichten, hat Vermögen, kann als Erbe eingesetzt werden, in eigenem Namen klagen und verklagt werden. [85] However, in some species, mate choice is primarily by males, as in some fishes of the family Syngnathidae. Es lässt sich auch als Saldo aus Vermögen und Schulden definieren ("Residualgröße").Das Eigenkapital ist in der Bilanz aus der Passivseite ersichtlich: es umfasst bei Kapitalgesellschaften die in § 266 Abs. Das Eigenkapital ist der Teil des Kapitals, der den Eigentümern zusteht. Yet it is impossible that this should be the true view. Although the Moravian monk Gregor Mendel, the father of modern genetics, was a contemporary of Darwin's, his work lay in obscurity, only being rediscovered in 1900. Friedrich Engels, a German political philosopher and co-originator of the ideology of communism, wrote in 1872 that "Darwin did not know what a bitter satire he wrote on mankind, and especially on his countrymen, when he showed that free competition, the struggle for existence, which the economists celebrate as the highest historical achievement, is the normal state of the animal kingdom. Sie eine weitrechende Wirkung, etwa die unbeschränkte Geschäftsfähigkeit (§§ 104 ff. [80], Finally, selection can be classified according to the resource being competed for. [86][87], Phenotypic traits can be displayed in one sex and desired in the other sex, causing a positive feedback loop called a Fisherian runaway, for example, the extravagant plumage of some male birds such as the peacock. [133] For example, a class of heuristic optimisation algorithms known as genetic algorithms, pioneered by John Henry Holland in the 1970s and expanded upon by David E. Goldberg,[134] identify optimal solutions by simulated reproduction and mutation of a population of solutions defined by an initial probability distribution. Lexikon, ... Daneben gibt es ähnliche gesetzliche Ausnahmen für den noch nicht … [99] With reinforcement, however, natural selection can favor an increase in pre-zygotic isolation, influencing the process of speciation directly. The racial idea as the basis of our state has already accomplished much in this respect. 1. a. Zu den „Betroffenen“ zählen nicht nur natürliche Personen – also Menschen –, sondern auch juristische Personen und Personengemeinschaften. Natürliche Person - Definition, Erklärung und Unterschied juristische Person. ×Please note that the translation of the ABS Clearing-House is in progress. nondum conceptus), etwa die Einsetzung als Nacherben (vgl. oben), aber auch die Personengesellschaften aus dem Handelsgesetzbuch (oHG, KG etc. Because individuals with certain variants of the trait tend to survive and reproduce more than individuals with other less successful variants, the population evolves. [17] The concept was simple but powerful: individuals best adapted to their environments are more likely to survive and reproduce. Natürliche Person – Weitere Begriffe im Umkreis, Erlangen der Deutschen Staatsangehörigkeit nach RuStaG (1913), Sträfling scheitert mit Klage gegen Gott. [82] An alternate theory proposed by the same Ronald Fisher in 1930 is the sexy son hypothesis, that mothers want promiscuous sons to give them large numbers of grandchildren and so choose promiscuous fathers for their children. [13], The early 19th-century zoologist Jean-Baptiste Lamarck suggested the inheritance of acquired characteristics as a mechanism for evolutionary change; adaptive traits acquired by an organism during its lifetime could be inherited by that organism's progeny, eventually causing transmutation of species. As a result, the genetic variation at those sites is higher than at sites where variation does influence fitness. [38][39] Wij bieden vakantiewoningen van een gezellig eenkamer-appartement in Florence, Italië, met uitzicht over de Ponte Vecchio tot luxe villa's in Toscane met 10 slaapkamers en alles daar tussenin. Grundsätzlich sind alle Daten, die sich einer bestimmten oder bestimmbaren natürlichen Person zuordnen lassen. One mechanism for this is heterozygote advantage, where individuals with two different alleles have a selective advantage over individuals with just one allele. Sexual selection results from competition for mates. Being such by birth or origin: a native Scot. Following Darwin, natural selection is sometimes defined as ecological selection, in which case sexual selection is considered a separate mechanism. Thus viability and survival selection may be defined separately and respectively as acting to improve the probability of survival before and after reproductive age is reached, while fecundity selection may be split into additional sub-components including sexual selection, gametic selection, acting on gamete survival, and compatibility selection, acting on zygote formation. The mathematics of "improvement in fitness was described by Kleinman. Fixation or substitution is not required for this "improvement in fitness". [111], Genetic linkage occurs when the loci of two alleles are in close proximity on a chromosome. On the Origin of Species (1st edition). The addition of molecular genetics has led to evolutionary developmental biology, which explains evolution at the molecular level. April 2018, veröffentlichten Beschluss (Az. [89] This is an evolutionary arms race, in which bacteria develop strains less susceptible to antibiotics, while medical researchers attempt to develop new antibiotics that can kill them. Weil sie kein Mensch, sondern eine Körperschaft ist, kann die Ordensgemeinschaft weder als „Person des Vertrauens“ noch anderweitig als „Beteiligte“ hinzugezogen werden, wie der Bundesgerichtshof (BGH) in Karlsruhe in einem am Freitag, 19. [62] Haldane called this process "substitution" or more commonly in biology, this is called "fixation". : XII ZB 589/17). [74][75] However, this does not imply that natural selection is always directional and results in adaptive evolution; natural selection often results in the maintenance of the status quo by eliminating less fit variants.[57]. W. D. Hamilton conceived of kin selection in 1964. Disruptive selection may cause sympatric speciation through niche partitioning. Die Suche erfolgt anhand von Hinweisen und eines Kompasses. Die Geschäftsfähigkeit gehört zur Handlungsfähigkeit, die wiederum von der Rechtsfähigkeit zu unterscheiden ist. [115], In the words of the philosopher Daniel Dennett, "Darwin's dangerous idea" of evolution by natural selection is a "universal acid," which cannot be kept restricted to any vessel or container, as it soon leaks out, working its way into ever-wider surroundings. AKTUELL: NEUES GESETZ IN SERBIEN! After the publication of On the Origin of Species,[27] educated people generally accepted that evolution had occurred in some form. [63] An empirical example of "improvement in fitness" is given by the Kishony Mega-plate experiment. [137], Mechanism of evolution by differential survival and reproduction of individuals, Heritable variation, differential reproduction, Darwin, Charles (1859). A distinction must be made between the concept of "survival of the fittest" and "improvement in fitness". [106][107], A portion of all genetic variation is functionally neutral, producing no phenotypic effect or significant difference in fitness. [127] Other aspects of human behaviour and social structures, from specific cultural norms such as incest avoidance to broader patterns such as gender roles, have been hypothesised to have similar origins as adaptations to the early environment in which modern humans evolved. [79], Selection can also be classified by the level or unit of selection. [97], Speciation requires a degree of reproductive isolation—that is, a reduction in gene flow. Any of these changes might have an effect that is highly advantageous or highly disadvantageous, but large effects are rare. Dies ist etwa bei der Erbfähigkeit nach § 1923 Absatz 2 BGB der Fall. [16], In 1859, Charles Darwin set out his theory of evolution by natural selection as an explanation for adaptation and speciation. §§ 106 ff. The problem does not occur in allopatric speciation with geographically separated populations, which can diverge with different sets of mutations. Allein das BGB kennt eine Vielzahl von Rechtsstellungen, die ein bestimmtes Alter, ein bestimmtes Geschlecht oder ein sonstiges besonderes Merkmal voraussetzen. However, many mutations in non-coding DNA have deleterious effects. Following Darwin's primary usage, the term is used to refer both to the evolutionary consequence of blind selection and to its mechanisms. Some nonlethal regulatory mutations occur in HOX genes in humans, which can result in a cervical rib[95] or polydactyly, an increase in the number of fingers or toes. Die Handlungsfähigkeit meint nämlich die Fähigkeit, durch eigenes Handeln Rechtswirkungen hervorzurufen. Hirntod) ein. Das entscheidende Merkmal der natürlichen Person ist also die Rechtsfähigkeit. 1 Datenschutz-Grundverordnung). Selective sweeps can be detected by measuring linkage disequilibrium, or whether a given haplotype is overrepresented in the population. Auch stark verwirrte Patienten haben bei der Bestellung eines Betreuers grundsätzlich das Recht, sich einen bestimmten Betreuer zu wünschen. [72], Natural selection can act on any heritable phenotypic trait,[73] and selective pressure can be produced by any aspect of the environment, including sexual selection and competition with members of the same or other species. [30][31] The fifth edition of On the Origin of Species published in 1869 included Spencer's phrase as an alternative to natural selection, with credit given: "But the expression often used by Mr. Herbert Spencer of the Survival of the Fittest is more accurate, and is sometimes equally convenient. [108] Neutral events can radically reduce genetic variation through population bottlenecks. [78], Another option is to classify selection by the life cycle stage at which it acts. Der Zementhersteller LafargeHolcim ist der grösste Schweizer Emittent von CO 2. Juni 2018 in Kraft. Onze villa's en boerderijen zijn de mooiste selectie van vakantiehuizen in Toscane. Because background selection is a result of deleterious new mutations, which can occur randomly in any haplotype, it does not produce clear blocks of linkage disequilibrium, although with low recombination it can still lead to slightly negative linkage disequilibrium overall. [44] The result of this would be the formation of new species. [118] On this view, life may have come into existence when RNA chains first experienced the basic conditions, as conceived by Charles Darwin, for natural selection to operate. Chapter 4, page 88. B. S. Haldane introduced the concept of the "cost" of natural selection. As long as there is some variation between them and that variation is heritable, there will be an inevitable selection of individuals with the most advantageous variations. Hier begint u met het plannen van uw volgende vakantie in Toscane, Italië. Eine Lebensfähigkeit ist wiederum nicht erforderlich. Für einen solchen Vorschlag... Karlsruhe (jur). [56], Natural variation occurs among the individuals of any population of organisms. This can occur in diploid species (with pairs of chromosomes) when heterozygous individuals (with just one copy of the allele) have a higher fitness than homozygous individuals (with two copies). For teeth and all other natural things either invariably or normally come about in a given way; but of not one of the results of chance or spontaneity is this true. In this way the natural environment of an organism "selects for" traits that confer a reproductive advantage, causing evolutionary change, as Darwin described. [92][93] Although both mutation rates and average fitness effects of mutations are dependent on the organism, a majority of mutations in humans are slightly deleterious. If an organism lives half as long as others of its species, but has twice as many offspring surviving to adulthood, its genes become more common in the adult population of the next generation. [101], Some traits are governed by only a single gene, but most traits are influenced by the interactions of many genes. native synonyms, native pronunciation, native translation, English dictionary definition of native. [123], The social implications of the theory of evolution by natural selection also became the source of continuing controversy. Throughout the lives of the individuals, their genomes interact with their environments to cause variations in traits. In the 3rd edition of 1861 Darwin acknowledged that others—like William Charles Wells in 1813, and Patrick Matthew in 1831—had proposed similar ideas, but had neither developed them nor presented them in notable scientific publications. In kin selection and intragenomic conflict, gene-level selection provides a more apt explanation of the underlying process. BGB, das Ende der elterlichen Sorge (§ 1626 Absatz 1 BGB), die Ehemündigkeit (§ 1303 BGB), die unbeschränkte Testierfähigkeit (§§ 2247 Absatz 4, 2229 Absatz 1 BGB) oder die Prozessfähigkeit (§ 52 ZPO). Finally, balancing selection can occur through frequency-dependent selection, where the fitness of one particular phenotype depends on the distribution of other phenotypes in the population. Das Betreuungsgericht darf den Wunsch nur dann ablehnen, wenn der vorgeschlagene Betreuer seine Tätigkeit voraussichtlich nicht zum Wohl des Betroffenen ausüben wird, entschied der Bundesgerichtshof (BGH) in Karlsruhe in einem am Mittwoch, 18. The polymorphism at the human ABO blood group locus has been explained in this way. 1. [34] With the early 20th century integration of evolution with Mendel's laws of inheritance, the so-called modern synthesis, scientists generally came to accept natural selection. During the formation of gametes, recombination reshuffles the alleles. [119][120] The three primary adaptive capacities could logically have been: (1) the capacity to replicate with moderate fidelity (giving rise to both heritability and variation of type), (2) the capacity to avoid decay, and (3) the capacity to acquire and process resources. Some biologists recognise just two types: viability (or survival) selection, which acts to increase an organism's probability of survival, and fecundity (or fertility or reproductive) selection, which acts to increase the rate of reproduction, given survival. The concept of natural selection originally developed in the absence of a valid theory of heredity; at the time of Darwin's writing, science had yet to develop modern theories of genetics. [66], In biology, competition is an interaction between organisms in which the fitness of one is lowered by the presence of another. Selection can be divided into three classes, on the basis of its effect on allele frequencies: directional, stabilizing, and disruptive selection. Therefore action for an end is present in things which come to be and are by nature. Since a selective sweep also results in selection of neighbouring alleles, the presence of a block of strong linkage disequilibrium might indicate a 'recent' selective sweep near the centre of the block. The environment of a genome includes the molecular biology in the cell, other cells, other individuals, populations, species, as well as the abiotic environment. Eigenkapital Definition. By analogy to the action of natural selection on genes, the concept of memes—"units of cultural transmission," or culture's equivalents of genes undergoing selection and recombination—has arisen, first described in this form by Richard Dawkins in 1976[128] and subsequently expanded upon by philosophers such as Daniel Dennett as explanations for complex cultural activities, including human consciousness. In his book Genetics and the Origin of Species (1937), Theodosius Dobzhansky established the idea that mutation, once seen as a rival to selection, actually supplied the raw material for natural selection by creating genetic diversity. [110] When genetic variation does not result in differences in fitness, selection cannot directly affect the frequency of such variation. [59] A recent study, using image analysis and avian vision models, shows that pale individuals more closely match lichen backgrounds than dark morphs and for the first time quantifies the camouflage of moths to predation risk. He was in the process of writing his "big book" to present his research when the naturalist Alfred Russel Wallace independently conceived of the principle and described it in an essay he sent to Darwin to forward to Charles Lyell. [15], Between 1835 and 1837, the zoologist Edward Blyth worked on the area of variation, artificial selection, and how a similar process occurs in nature. Empfänger ist eine natürliche oder juristische Person, Behörde, Einrichtung oder andere Stelle, der personenbezogene Daten offengelegt werden, unabhängig davon, ob es sich bei ihr um einen Dritten handelt oder nicht. - Verbindliche Eintragung in das Zentralregister wirtschaftlicher Eigentümer, DSGVO: Kundendaten können aufgrund berechtigten Interesses herausgegeben werden, Auch bei Millionen-Vermögen eines Betreuten hat Berufsbetreuer kein Vorrang, Auch Demenzkranke können einen Betreuer für sich vorschlagen, Ordensgemeinschaft bleibt bei Betreuungsverfahren für Nonne außen vor, » HESSISCHER-VGH, 03.04.2002, 5 UZ 10/02. In contrast, K-selected species are strong competitors in crowded niches, and invest more heavily in much fewer offspring, each with a relatively high probability of surviving to adulthood. The widespread misuse of antibiotics has selected for microbial resistance to antibiotics in clinical use, to the point that the methicillin-resistant Staphylococcus aureus (MRSA) has been described as a "superbug" because of the threat it poses to health and its relative invulnerability to existing drugs. Motoo Kimura's neutral theory of molecular evolution by genetic drift proposes that this variation accounts for a large fraction of observed genetic diversity. Group selection, if it occurs, acts on groups of organisms, on the assumption that groups replicate and mutate in an analogous way to genes and individuals. Es steht der Rechtsfähigkeit also auch nicht entgegen, wenn das Kind kurz nach der Geburt verstirbt. [119][120] These capacities would have been determined initially by the folded configurations (including those configurations with ribozyme activity) of the RNA replicators that, in turn, would have been encoded in their individual nucleotide sequences. The success of this theory raised awareness of the vast scale of geological time and made plausible the idea that tiny, virtually imperceptible changes in successive generations could produce consequences on the scale of differences between species. We would like to show you a description here but the site won’t allow us. "[25] In a letter to Charles Lyell in September 1860, Darwin regretted the use of the term "Natural Selection", preferring the term "Natural Preservation". In 1893 H. G. Wells imagined "The Man of the Year Million", transformed by natural selection into a being with a huge head and eyes, and shrunken body. Natural selection reduces genetic variation by eliminating maladapted individuals, and consequently the mutations that caused the maladaptation. 2162, 2178 BGB). A famous example of a vestigial structure, the eye of the blind mole-rat, is believed to retain function in photoperiod perception. In particular, if the trait is quantitative and univariate then both higher and lower trait levels are favoured. Es gibt allerdings auch gesetzliche Ausnahmen, durch die bereits der Nasciturus (also der ungeborene Mensch) rechtsfähig ist. And in like manner as to the other parts in which there appears to exist an adaptation to an end. [27][37][51][52] It is sometimes helpful to explicitly distinguish between selection's mechanisms and its effects; when this distinction is important, scientists define "(phenotypic) natural selection" specifically as "those mechanisms that contribute to the selection of individuals that reproduce", without regard to whether the basis of the selection is heritable. [94], Some mutations occur in "toolkit" or regulatory genes. [116] Thus, in the last decades, the concept of natural selection has spread from evolutionary biology to other disciplines, including evolutionary computation, quantum Darwinism, evolutionary economics, evolutionary epistemology, evolutionary psychology, and cosmological natural selection. [88] Response strategies typically include the use of different, stronger antibiotics; however, new strains of MRSA have recently emerged that are resistant even to these drugs. Sexual selection typically proceeds via fecundity selection, sometimes at the expense of viability. Changes in these often have large effects on the phenotype of the individual because they regulate the function of many other genes. Die Plauderecke bietet allen Besuchern von Baby-Vornamen.de einen Ort, um ungestört über schöne Vornamen, die Schwangerschaft oder andere Dinge zu plaudern. More generally, intrasexual selection is often associated with sexual dimorphism, including differences in body size between males and females of a species. This process can continue until the allele is fixed and the entire population shares the fitter phenotype. Though natural selection acts on individuals, the effects of chance mean that fitness can only really be defined "on average" for the individuals within a population. Neben der Geschäftsfähigkeit umfasst die Handlungsfähigkeit daher auch die Deliktsfähigkeit (§§ 827 f. BGB) und die Verantwortlichkeit für die Verletzung von Verbindlichkeiten (§ 276 Absatz 1 Satz 2 BGB). The principles of game theory have been applied to understand the fitness distributions in these situations, particularly in the study of kin selection and the evolution of reciprocal altruism. [14] This theory, Lamarckism, was an influence on the Soviet biologist Trofim Lysenko's antagonism to mainstream genetic theory as late as the mid 20th century. as the teeth, for example, grow by necessity, the front ones sharp, adapted for dividing, and the grinders flat, and serviceable for masticating the food; since they were not made for the sake of this, but it was the result of accident. [126], More recently, work among anthropologists and psychologists has led to the development of sociobiology and later of evolutionary psychology, a field that attempts to explain features of human psychology in terms of adaptation to the ancestral environment. Others split the life cycle into further components of selection. However, it is intrinsic to the concept of a species that hybrids are selected against, opposing the evolution of reproductive isolation, a problem that was recognised by Darwin.