Subspecies Purity vs. Generic Animals
... into a undersized Balinese. Yet though the subspecies are disappearing one after the other, scientific dogma insists that racial purity must be preserved, and that generic [i.e., of unknown lineage] tigers in zoos should be earmarked for extinction in accordance with a carefully maintained studbook. ...
... into a undersized Balinese. Yet though the subspecies are disappearing one after the other, scientific dogma insists that racial purity must be preserved, and that generic [i.e., of unknown lineage] tigers in zoos should be earmarked for extinction in accordance with a carefully maintained studbook. ...
Chapter1
... of interacting organisms (plant, animal and microbe = biocoenosis) and their interactions with their physical and chemical environment (biotope) often linked to an area. Ecosystem diversity is defined as the variety of ecosystems within a bigger landscape and their variability over time. Ecologi ...
... of interacting organisms (plant, animal and microbe = biocoenosis) and their interactions with their physical and chemical environment (biotope) often linked to an area. Ecosystem diversity is defined as the variety of ecosystems within a bigger landscape and their variability over time. Ecologi ...
Niche diversity in crustacean cryptic species
... Leibold and McPeek 2006) because it is not apparent that these ‘‘cryptic species’’ (used here to refer to species with very high phenotypic similarity) possess sufficient phenotypic and ecological disparity to foster coexistence through niche differentiation. A variety of mechanisms have been propos ...
... Leibold and McPeek 2006) because it is not apparent that these ‘‘cryptic species’’ (used here to refer to species with very high phenotypic similarity) possess sufficient phenotypic and ecological disparity to foster coexistence through niche differentiation. A variety of mechanisms have been propos ...
video slide - My Teacher Site
... Limitations of the Biological Species Concept • The biological species concept cannot be applied to fossils ...
... Limitations of the Biological Species Concept • The biological species concept cannot be applied to fossils ...
hybrid zone
... • Depending on the species in question, speciation might require the change of only a single allele or many alleles – For example, in Japanese Euhadra snails, the direction of shell spiral affects mating and is controlled by a single gene ...
... • Depending on the species in question, speciation might require the change of only a single allele or many alleles – For example, in Japanese Euhadra snails, the direction of shell spiral affects mating and is controlled by a single gene ...
Model of unequal chromosomal crossing over in DNA sequences1
... some cases, be of the order of 100. SSR are of considerable practical and theoretical interest due to their high polymorphism [2], i.e. the length of SSR at the same DNA locus can vary from individual to individual. This property of SSR is used in genetic ngerprinting. The expansion of SSR in DNA s ...
... some cases, be of the order of 100. SSR are of considerable practical and theoretical interest due to their high polymorphism [2], i.e. the length of SSR at the same DNA locus can vary from individual to individual. This property of SSR is used in genetic ngerprinting. The expansion of SSR in DNA s ...
Species distribution
Species distribution is the manner in which a biological taxon is spatially arranged. Species distribution is not to be confused with dispersal, which is the movement of individuals away from their area of origin or from centers of high population density. A similar concept is the species range. A species range is often represented with a species range map. Biogeographers try to understand the factors determining a species' distribution. The pattern of distribution is not permanent for each species. Distribution patterns can change seasonally, in response to the availability of resources, and also depending on the scale at which they are viewed. Dispersion usually takes place at the time of reproduction. Populations within a species are translocated through many methods, including dispersal by people, wind, water and animals. Humans are one of the largest distributors due to the current trends in globalization and the expanse of the transportation industry. For example, large tankers often fill their ballasts with water at one port and empty them in another, causing a wider distribution of aquatic species.Biogeography is the study of the distribution of biodiversity over space and time. It is very useful in understanding species distribution through factors such as speciation, extinction, continental drift, glaciation, variation of sea levels, river capture and available resources. This branch of study not only gives a description of the species distribution, but also a geographical explanation for the distribution of particular species. The traditional biogeographic regions were first modeled by Alfred Wallace in The Geographical Distribution of Animals (1876). These were based on the work of Sclater's terrestrial biogeographic regions. Wallace's system was based on both birds and vertebrates, including non-flying mammals, which better reflect the natural divisions of the Earth due to their limited dispersal abilities.