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Running with the Red Queen: the role of biotic conflicts in evolution
Running with the Red Queen: the role of biotic conflicts in evolution

... RQ metaphor has been applied to different fields. For many evolutionary biologists, the RQH is most strongly associated with debates surrounding the evolution of sex. The RQH provides a mechanism by which sexual species are protected from elimination by asexuals despite the latter’s higher per capit ...
Repeated modification of early limb morphogenesis programmes
Repeated modification of early limb morphogenesis programmes

... regressions reflects that a change has occurred prior to the earliest developmental stages measured. During scaling, the absolute size of the trait changes, but in proportion to body size. Circles, morphogenesis; triangles, hatching; hexagons, adulthood. changes in the rate of limb growth, either fr ...
Genome-wide scans for loci under selection in
Genome-wide scans for loci under selection in

... Natural selection, which can be defined as the differential contribution of genetic variants to future generations, is the driving force of Darwinian evolution. Identifying regions of the human genome that have been targets of natural selection is an important step in clarifying human evolutionary hi ...
as a PDF - Todd Shackelford
as a PDF - Todd Shackelford

... the first place. Why do we feel pain at all? Why are we so motivated to pursue sex? The answer lies in that blind, unconscious, omnipresent driving force behind biological diversity on earth: natural selection. Only by looking at the mind as a product of natural selection can we arrive at a full exp ...
Adaptation and Evolutionary Theory
Adaptation and Evolutionary Theory

... own point of view. the majority of the scientific comn~unitythat Ignoring the parenthetical 'significant' (1) evolution has and does occur but hardly anyone could not help but be true. The uniqueness bought his natural-selection-explanation of it. of complex material systems is now taken for (For an ...
Review of P. Godfrey-Smith`s Darwinian populations and natural
Review of P. Godfrey-Smith`s Darwinian populations and natural

... Sterelny...), PGS claims that ENS does not require replicators (faithfully copied entities), but only that reproduction leads to parent-offspring similarity. This similarity can take the form of a faithful ‘copying’, but does not need to. The replicator view insists on the persistence of entities, i ...
Artificial ecosystem selection
Artificial ecosystem selection

... complex systems dynamics. Mathematical and computer simulation models of evolution tend to assume a simple relationship between phenotypic traits and their genetic basis, such as an altruistic behavior that is coded directly by an altruistic gene. In the case of our soil ecosystem experiment, we mig ...
Species selection and driven mechanisms jointly generate a large
Species selection and driven mechanisms jointly generate a large

... Introduction Evolution by natural selection is easy. Only heritable variation in fitness is needed for entities to evolve by natural selection (Lewontin 1970). In principle, many hierarchical levels can satisfy these criteria, from selfish genetic elements up through populations of organisms to the ...
PDF
PDF

... that the organisms made—e.g., fighting between males or females preferring males with big horns in titanotheres, eating bamboo in pandas—is very likely driven by behavioral persistence, possibly combined with phenomena such as genetic drift. That is, the very instigators of evolutionary trends that ...
Epigenetic inheritance speeds up evolution of artificial organisms
Epigenetic inheritance speeds up evolution of artificial organisms

... simulated step by step, enabling the computation of the dynamic phenotypic function during the life of the individual. In RAevol, the target phenotype may change during the life of the individual, either deterministically or randomly (Figure 1). The individual must then dynamically adapt to the curr ...
Mechanisms of constraints: the contributions of selection and
Mechanisms of constraints: the contributions of selection and

... changes caused by mutations of small effect or environmental variation during development. Traits may also lack phenotypic variation for nonadaptive reasons, including a loss of genetic variation through drift, or constraints imposed by development or genetic correlations with other traits under str ...
File
File

... characteristic determined by a recessive allele. The others are green, a characteristic determined by a dominant allele. A hurricane on the island kills most of the birds from this population. Only ten remain, and those birds all have yellow feathers. Which of the following statements is true? A) As ...
POSSIBLE LARGEST-SCALE TRENDS IN ORGANISMAL
POSSIBLE LARGEST-SCALE TRENDS IN ORGANISMAL

... Also omitted are methods for establishing that trends have occurred, such as recent cladistic methods for inferring ancestral character states (20a). Finally, the discussion is limited to features at the organism level, in other words, the size, complexity, fitness, and so on, of individual organism ...
The development of evolutionary theory since Darwin
The development of evolutionary theory since Darwin

... discussed. The scientist Yule stated that recessive factors (today better known as alleles) will disappear in the course of a few generations even if natural selection is absent because dominant factors (alleles) will establish themselves at any rate. Hardy disagreed with Yule’s statement, but he wa ...
Eco-genetic modeling of contemporary life
Eco-genetic modeling of contemporary life

... and size structure enables the analysis of phenotypically plastic populations with more than a single growth trajectory, and ecological feedback is readily included in the form of density dependence and frequency dependence. Stochasticity and life-history trade-offs can also be implemented. Critical ...
Evolutionary Dynamics as a Component of Stage
Evolutionary Dynamics as a Component of Stage

... population trajectory of an herbaceous perennial understory plant Trillium grandiflorum. Prior study has revealed that populations of this species are declining due to deer herbivory (Knight 2004). Here we show that deer selectively consume early-flowering individuals. Flowering time is known to hav ...
Understanding Natural Selection: Essential Concepts and Common
Understanding Natural Selection: Essential Concepts and Common

... difficult to fathom. For example, consider that beginning with a single Escherichia coli bacterium, and assuming that cell division occurs every 30 minutes, it would take less than a week for the descendants of this one cell to exceed the mass of the Earth. Of course, exponential population expansio ...
DOBZHANSKY ON EVOLUTIONARY DYNAMICS
DOBZHANSKY ON EVOLUTIONARY DYNAMICS

... variability ['Veränderlichkeit'] the unlikeness or diversity of individuals or groups of individuals within the boundaries of a species, so that species boundaries are at the same time the natural boundaries of variation" (1927, p. 15).7 These distinctions divide the study of variation in relation t ...
Competitive speciation
Competitive speciation

... only by matings between themselves, but also by matings between phenotypes of opposite extremes. Because intermediate progeny are unfit, extreme phenotypes enjoy enhanced fitness if they practice homogamy. Consequently, reproductive isolation between the extremes evolves and the intermediates disapp ...
Chapter 4 The remedy to genetic erosion problems
Chapter 4 The remedy to genetic erosion problems

... deviation (deviation of the heterozygote mean from the mean of the homozygotes) and the summation is over all polymorphic loci with genotypes differing in their impacts on the quantitative traits (reproductive fitness in the current context). The 2piqi term is reduced by a history of small populatio ...
evolutionary inferences from the analysis of exchangeability
evolutionary inferences from the analysis of exchangeability

... in direction among the six watersheds (i.e., nonparallel evolution), suggesting a weak role of deterministic natural selection— at least between generic “lake” and “stream” designations. (4) Lake–stream divergence in genetic (microsatellite) markers was sometimes in the same direction (parallel) and ...
population genetics - McGraw Hill Higher Education
population genetics - McGraw Hill Higher Education

... The genetic variation in all natural populations changes over the course of many generations. The term microevolution is used to describe changes in a population’s gene pool from generation to generation. Such change is rooted in two related phenomena (Table 24.1). First, the introduction of new gen ...
Evolutionary Psychology as Maladapted Psychology
Evolutionary Psychology as Maladapted Psychology

... the natural human sympathies would promote the common good. The mechanism for this evolution is free competition. This is fundamentally social evolution. Even in Social Statics, Spencer highlighted his individualism and emphasized our less flattering motives and dispositions. This was balanced by th ...
The evolutionary synthesis and Th. Dobzhansky
The evolutionary synthesis and Th. Dobzhansky

... more harmonious, better, more adapted for a life, than others. Owing to an action of natural selection, some of these combinations will die out, others will be indifferent, the third useful. The new mutation at once after its occurrence gets in this sorting device of combinative variability and sele ...
a new use for an old theory - PUC-SP
a new use for an old theory - PUC-SP

... older powers are concerned, although, from the more general point of view of natural law, their relations to older uses have not the character of accidents, since these relations are, for the most part, determined by universal properties and laws, which are not specially related to the needs and con ...
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Evolutionary landscape

An evolutionary landscape is a metaphor; a construct used to think about and visualize the processes of evolution (e.g. natural selection and genetic drift) acting on a biological entity ( e.g., a gene, protein, population, species). This entity can be viewed as searching or moving through a search space. For example, the search space of a gene would be all possible nucleotide sequences. The search space is only part of an evolutionary landscape. The final component is the ""y-axis,"" which is usually fitness. Each value along the search space can result in a high or low fitness for the entity. If small movements through search space causes small changes in fitness are relatively small, then the landscape is considered smooth. Smooth landscapes happen when most fixed mutations have little to no effect on fitness, which is what one would expect with the neutral theory of molecular evolution. In contrast, if small movements result in large changes in fitness, then the landscape is said to be rugged. In either case, movement tends to be toward areas of higher fitness, though usually not the global optima.What exactly constitutes an ""evolutionary landscape"" is confused in the literature. The term evolutionary landscape is often used interchangeably with adaptive landscape and fitness landscape, though other authors distinguish between them. As discussed below, different authors have different definitions of adaptive and fitness landscapes. Additionally, there is large disagreement whether it should be used as a visual metaphor disconnected from the underlying math, a tool for evaluating models of evolution, or a model in and of itself used to generate hypotheses and predictions. Clearly, the field of biology, specifically evolutionary biology and population genetics, needs to come to a consensus of what an evolutionary landscape is and how it should be used.
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