Information about Phenotypic Plasticity
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Norms of reaction for two genotypes. Genotype B shows a strongly bimodal distribution indicating differentiation into distinct phenotypes. Each phenotype is buffered against environmental variation - it is canalised.
Organisms of fixed genotype may differ in the amount of phenotypic plasticity they display when exposed to the same environmental change. Hence phenotypic plasticity can evolve and be adaptive if fitness is increased by changing phenotype. Immobile organisms such as plants have well developed phenotypic plasticity giving a clue to the adaptive significance of plasticity.
A highly illustrative example of phenotypic plasticity is found in the social insects, colonies of which depend on the division of their members into distinct castes, such as workers and guards. These two castes differ dramatically in appearance and behaviour. However, these differences are not genetic; they arise during development and depend on the manner of treatment of the eggs by the queen and the workers, who manipulate such factors as embryonic diet and incubation temperature. The genome of each individual contains all the instructions needed to develop into any one of several 'morphs', but only the genes that form part of one developmental program are activated.
In epidemiology, a popular theory is that rising incidences of coronary heart disease and Type II diabetes in human populations undergoing industrialization is due to a mismatch between a metabolic phenotype determined in development and the nutritional environment an individual is subsequently exposed to. This is known as the 'Thrifty phenotype' hypothesis (see Evolutionary psychology).
See also
External links
- Special issue of the Journal of Experimental Biology concerning phenotypic plasticity
- Massimo Pigliucci’s Evolutionary Ecology Lab web page
- Developmental Plasticity and Evolution - review of the book from American Scientist
Further reading
- Mary Jane West-Eberhard (2003). Developmental Plasticity and Evolution. Oxford University Press.
The development of phenotype | |
|---|---|
| Key concepts | Genotype-phenotype distinction Norms of reaction Gene-environment interaction Heritability Quantitative genetics |
| Genetic architecture | Dominance relationship Epistasis Polygenic inheritance Pleiotropy Plasticity Canalisation Fitness landscape |
| Non-genetic influences | Epigenetics Maternal effect Dual inheritance theory |
| Developmental architecture | Segmentation Modularity |
| Evolution of genetic systems | Evolvability Mutational robustness Evolution of sex |
| Influential figures | C. H. Waddington Richard Lewontin |
| Debates | Nature versus nurture |
| List of evolutionary biology topics | |
Genotype describes the genetic constitution of an individual, that is the specific allelic makeup of an individual, usually with reference to a specific character under consideration [1].
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phenotype describes the total physical appearance of an organism, as opposed to its genotype. This genotype-phenotype distinction was proposed by Wilhelm Johannsen in 1911 to make clear the difference between an organism's heredity and what that heredity produces.
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In ecology and genetics, a norm of reaction describes the pattern of phenotypic expression of a single genotype across a range of environments. One use of norms of reaction is in describing how different species—especially related species—respond to varying environments.
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For the band, see .
Morphogenesis (from the Greek morphê shape and genesis creation) is one of three fundamental aspects of developmental biology along with the control of cell growth and cellular differentiation.
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Eusociality is the phenomenon of reproductive specialization found in some animals. It generally involves the production of sterile members of the species, which carry out specialized tasks, effectively caring for the reproductive members.
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Caste systems are traditional, hereditary systems of social restriction and social stratification, enforced by law or common practice, based on endogamy, , economic status, race and ethnicity.
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In biology the genome of an organism is its whole hereditary information and is encoded in the DNA (or, for some viruses, RNA). This includes both the genes and the non-coding sequences of the DNA.
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Polymorphism in biology occurs when two or more clearly different types exist in the same population of the same species— in other words, the occurrence of more than one form or morph. The caste system in ants is an example.
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Epidemiology is the study of factors affecting the health and illness of populations, and serves as the foundation and logic of interventions made in the interest of public health and preventive medicine.
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Coronary heart disease
Classification & external resources
ICD-10 I20-I25
ICD-9 410 - 414 , 429.2
Coronary heart disease (CHD), also called coronary artery disease (CAD), ischaemic heart disease, atherosclerotic heart disease, is the end result
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Classification & external resources
ICD-10 I20-I25
ICD-9 410 - 414 , 429.2
Coronary heart disease (CHD), also called coronary artery disease (CAD), ischaemic heart disease, atherosclerotic heart disease, is the end result
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Diabetes mellitus type 2 (formerly called diabetes mellitus type II, non insulin-dependent diabetes (NIDDM), obesity related diabetes, or adult-onset diabetes) is a metabolic disorder that is primarily characterized by insulin resistance, relative insulin deficiency, and
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Industrialisation (also spelt Industrialization) or an Industrial Revolution is a process of social and economic change whereby a human group is transformed from a pre-industrial society (an economy where the amount of capital accumulated per capita is low) to an
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thrifty phenotype (Hales & Barker, 1992[1]). Individuals with a thrifty phenotype will have "a smaller body size, a lowered metabolic rate and a reduced level of behavioural activity… adaptations to an environment that is chronically short of food" (Bateson &
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Evolutionary psychology (abbreviated EP) is a theoretical approach to psychology that attempts to explain mental and psychological traits—such as memory, perception, or language—as adaptations, i.e., as the functional products of natural selection.
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Developmental Biology is the official journal of the Society for Developmental Biology. It publishes research on the mechanisms of development, differentiation, and growth in animals and plants at the molecular, cellular, and genetic levels.
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Evolutionary physiology is the study of physiological evolution, which is to say, the manner in which the functional characteristics of individuals in a population of organisms have responded to selection across multiple generations during the history of the population
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For the band, see .
Morphogenesis (from the Greek morphê shape and genesis creation) is one of three fundamental aspects of developmental biology along with the control of cell growth and cellular differentiation.
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phenotype describes the total physical appearance of an organism, as opposed to its genotype. This genotype-phenotype distinction was proposed by Wilhelm Johannsen in 1911 to make clear the difference between an organism's heredity and what that heredity produces.
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The genotype-phenotype distinction must be drawn when trying to understand the inheritance of traits and their evolution. The genotype of an organism represents its exact genetic makeup, that is, the particular set of genes it possesses.
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In ecology and genetics, a norm of reaction describes the pattern of phenotypic expression of a single genotype across a range of environments. One use of norms of reaction is in describing how different species—especially related species—respond to varying environments.
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Gene-environment interaction is a term used to describe any phenotypic effects that are due to interactions between the environment and genes. Naive nature versus nurture debates assume that variation in a given trait is primarily due to either genes, or the individual's
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In genetics, heritability is the proportion of phenotypic variation in a population that is attributable to genetic variation among individuals. Variation among individuals may be due to genetic and/or environmental factors.
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Quantitative genetics is the study of continuous traits (such as height or weight) and its underlying mechanisms. It is effectively an extension of simple Mendelian inheritance in that the combined effect of the many underlying genes results in a continuous distribution of
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Genetic architecture refers to the underlying genetic basis of a phenotypic trait. A synonymous term is the `genotype-phenotype map', the way that genotypes map to the phenotypes.
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dominance relationship refers to how the alleles for a locus interact to produce a phenotype.
There are three main kinds of dominance relationships:
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There are three main kinds of dominance relationships:
- Simple dominance or complete dominance (simple Mendelian inheritance) over a recessive trait
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Epistasis is the interaction between genes. Epistasis takes place when the action of one gene is modified by one or several other genes, which are sometimes called modifier genes.
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Polygenic inheritance, also known as quantitative or multifactorial inheritance refers to inheritance of a phenotypic characteristic (trait) that is attributable to two or more genes and their interaction with the environment.
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Pleiotropy occurs when a single gene influences multiple phenotypic traits. Consequently, a new mutation in the gene will have an effect on all traits simultaneously. This can become a problem when selection on one trait favours one specific mutant, while the selection at the other
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Canalisation (canalization in American English) is a measure of the ability of a genotype to produce the same phenotype regardless of variability of its environment. The term canalisation was coined by C. H.
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In evolutionary biology, fitness landscapes or adaptive landscapes are used to visualize the relationship between genotypes (or phenotypes) and reproductive success. It is assumed that every genotype has a well defined replication rate (often referred to as fitness).
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