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Ambidirectional Dominance
Ambidirectional dominance occurs in a situation where multiple genes influence a phenotype and dominance is in different directions depending on the gene. For example, for gene A increased height is dominant, while for gene B decreased height is dominant. The opposite situation, where all genes show dominance in the same direction, is called directional dominance. In the same example, for both genes A and B increased height is dominant. According to Broadhurst, ambidirectional dominance is the result of stabilising selection in the evolutionary past. Ambidirectional dominance has been found for exploratory behaviours in mice and paradise fish The paradise fish, paradise-fish, paradisefish, or paradise gourami (''Macropodus opercularis'') is a species of gourami found in most types of fresh water in East Asia, ranging from the Korean Peninsula to northern Vietnam. This species can .... References Genetics Selection {{genetics-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gene
In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a basic unit of heredity and the molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protein-coding genes and noncoding genes. During gene expression, the DNA is first copied into RNA. The RNA can be directly functional or be the intermediate template for a protein that performs a function. The transmission of genes to an organism's offspring is the basis of the inheritance of phenotypic traits. These genes make up different DNA sequences called genotypes. Genotypes along with environmental and developmental factors determine what the phenotypes will be. Most biological traits are under the influence of polygenes (many different genes) as well as gen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenotype
In genetics, the phenotype () is the set of observable characteristics or traits of an organism. The term covers the organism's morphology or physical form and structure, its developmental processes, its biochemical and physiological properties, its behavior, and the products of behavior. An organism's phenotype results from two basic factors: the expression of an organism's genetic code, or its genotype, and the influence of environmental factors. Both factors may interact, further affecting phenotype. When two or more clearly different phenotypes exist in the same population of a species, the species is called polymorphic. A well-documented example of polymorphism is Labrador Retriever coloring; while the coat color depends on many genes, it is clearly seen in the environment as yellow, black, and brown. Richard Dawkins in 1978 and then again in his 1982 book ''The Extended Phenotype'' suggested that one can regard bird nests and other built structures such as cad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dominance (genetics)
In genetics, dominance is the phenomenon of one variant (allele) of a gene on a chromosome masking or overriding the effect of a different variant of the same gene on the other copy of the chromosome. The first variant is termed dominant and the second recessive. This state of having two different variants of the same gene on each chromosome is originally caused by a mutation in one of the genes, either new (''de novo'') or inherited. The terms autosomal dominant or autosomal recessive are used to describe gene variants on non-sex chromosomes ( autosomes) and their associated traits, while those on sex chromosomes (allosomes) are termed X-linked dominant, X-linked recessive or Y-linked; these have an inheritance and presentation pattern that depends on the sex of both the parent and the child (see Sex linkage). Since there is only one copy of the Y chromosome, Y-linked traits cannot be dominant or recessive. Additionally, there are other forms of dominance such as incomplete d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stabilizing Selection
Stabilizing selection (not to be confused with negative or purifying selection) is a type of natural selection in which the population mean stabilizes on a particular non-extreme trait value. This is thought to be the most common mechanism of action for natural selection because most traits do not appear to change drastically over time. Stabilizing selection commonly uses negative selection (a.k.a. purifying selection) to select against extreme values of the character. Stabilizing selection is the opposite of disruptive selection. Instead of favoring individuals with extreme phenotypes, it favors the intermediate variants. Stabilizing selection tends to remove the more severe phenotypes, resulting in the reproductive success of the norm or average phenotypes. This means that most common phenotype in the population is selected for and continues to dominate in future generations. History The Ukrainian evolutionary biologist Ivan Schmalhausen founded the theory of stabilizing s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Exploration
Exploration refers to the historical practice of discovering remote lands. It is studied by geographers and historians. Two major eras of exploration occurred in human history: one of convergence, and one of divergence. The first, covering most of ''Human, Homo sapiens'' history, saw humans Recent African origin of modern humans, moving out of Africa, settling in new lands, and developing distinct cultures in relative isolation. Early explorers settled in Europe and Asia; 14,000 years ago, some crossed the Settlement of the Americas, Ice Age land bridge from Siberia to Alaska, and moved southbound to settle in the Americas. For the most part, these cultures were ignorant of each other's existence. The second period of exploration, occurring over the last 10,000 years, saw increased cross-cultural exchange through trade and exploration, and marked a new era of cultural intermingling, and more recently, convergence. Early writings about exploration date back to the 4th millennium B ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mouse
A mouse ( : mice) is a small rodent. Characteristically, mice are known to have a pointed snout, small rounded ears, a body-length scaly tail, and a high breeding rate. The best known mouse species is the common house mouse (''Mus musculus''). Mice are also popular as pets. In some places, certain kinds of field mice are locally common. They are known to invade homes for food and shelter. Mice are typically distinguished from rats by their size. Generally, when a muroid rodent is discovered, its common name includes the term ''mouse'' if it is smaller, or ''rat'' if it is larger. The common terms ''rat'' and ''mouse'' are not taxonomically specific. Typical mice are classified in the genus '' Mus'', but the term ''mouse'' is not confined to members of ''Mus'' and can also apply to species from other genera such as the deer mouse, ''Peromyscus''. Domestic mice sold as pets often differ substantially in size from the common house mouse. This is attributable to breeding a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heredity (journal)
''Heredity'' is a monthly peer reviewed scientific journal published by Nature Portfolio. It covers heredity in a biological sense, i.e. genetics. The journal was founded by Ronald Fisher and C. D. Darlington in 1947 and is the official journal of The Genetics Society. From 1996 the publishing was taken over by Nature Portfolio. The editor-in-chief is Sara Goodacre. According to the ''Journal Citation Reports'', the journal has a 2021 impact factor The impact factor (IF) or journal impact factor (JIF) of an academic journal is a scientometric index calculated by Clarivate that reflects the yearly mean number of citations of articles published in the last two years in a given journal, as i ... of 3.832, ranking it 61st out of 173 journals in the category "Ecology", 19th out of 51 journals in the category "Evolutionary Biology", and 79th out of 175 journals in the category "Genetics & Heredity". References External links * The Genetics Society* Genetics in the Uni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Behavioural Brain Research
''Behavioural Brain Research'' is a peer-reviewed scientific journal published by Elsevier. The journal publishes articles in the field of behavioural neuroscience. Volume 1 appeared in 1980 and issues appeared 6 times per year; as submissions increased it switched to a higher frequency and currently 20 issues per year are published. Abstracting and indexing The journal is abstracted and indexed in Animal Behavior Abstracts, BIOSIS Previews, Chemical Abstracts Service, Current Contents/Life Sciences, EMBASE, MEDLINE, PsycINFO, Science Citation Index, and Scopus. According to the ''Journal Citation Reports'', its 2020 impact factor The impact factor (IF) or journal impact factor (JIF) of an academic journal is a scientometric index calculated by Clarivate that reflects the yearly mean number of citations of articles published in the last two years in a given journal, as i ... is 3.332. References External links *{{Official website, http://www.elsevier.com/wps/find/journal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paradise Fish
The paradise fish, paradise-fish, paradisefish, or paradise gourami (''Macropodus opercularis'') is a species of gourami found in most types of fresh water in East Asia, ranging from the Korean Peninsula to northern Vietnam. This species can reach a standard length of , though most are only about . Paradise gouramis were one of the first ornamental fish available to western fishkeeping, aquarium keepers, having been imported 1869 to France by the French aquarium fish importer Pierre Carbonnier in Paris. The paradise fish is one of the more aggressive members of its family. It is more aggressive than the three spot gourami, yet less pugnacious in nature than the less commonly kept combtail. Behaviour Paradise fish are fairly combative, harassing and attacking each other, as well as potentially assaulting and killing small fish. During a fight, the paradise fish will often change its color, usually displaying dark blue lateral lines on the sides of their bodies; extend its fi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Behavior Genetics (journal)
''Behavior Genetics'' is a peer-reviewed scientific journal published monthly by Springer Science+Business Media that is covering "research in the inheritance of behavior". It is the official journal of the Behavior Genetics Association. The journal was established in 1971 with Steven G. Vandenberg as its founding editor-in-chief. The abstracts of the annual meetings are printed in the journal. Each year, the editorial board chooses a particularly meritorious paper in the previous year's volume of the journal for the Fulker Award, acknowledged by "$1000 and a good bottle of wine" as well as a citation made in the journal. This award was created in the honor of David Fulker, a past president of the Behavior Genetics Association (1982) and former editor-in-chief of the journal. Abstracting and indexing The journal is abstracted in '' Biological Abstracts/BIOSIS Previews, CAB Abstracts, Current Awareness in Biological Sciences, Current Contents/Social & Behavioral Sciences'' and '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genetics
Genetics is the study of genes, genetic variation, and heredity in organisms.Hartl D, Jones E (2005) It is an important branch in biology because heredity is vital to organisms' evolution. Gregor Mendel, a Moravian Augustinian friar working in the 19th century in Brno, was the first to study genetics scientifically. Mendel studied "trait inheritance", patterns in the way traits are handed down from parents to offspring over time. He observed that organisms (pea plants) inherit traits by way of discrete "units of inheritance". This term, still used today, is a somewhat ambiguous definition of what is referred to as a gene. Trait inheritance and molecular inheritance mechanisms of genes are still primary principles of genetics in the 21st century, but modern genetics has expanded to study the function and behavior of genes. Gene structure and function, variation, and distribution are studied within the context of the cell, the organism (e.g. dominance), and within the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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