microevolution

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mi·cro·ev·o·lu·tion

(mī'krō-ev'ŏ-lū'shŭn),
The evolution of bacteria and other microorganisms through mutations.

microevolution

(mī′krō-ĕv′ə-lo͞o′shən, -ē′və-)
n.
Small-scale evolution consisting of genetic changes occurring usually within a single species and over a shorter period of time than in macroevolution.

mi′cro·ev′o·lu′tion·ar′y adj.

microevolution

A term of art referring to evolution that occurs below the level of speciation, which corresponds to the shifts in allele frequencies occurring over time in a particular population, regardless of whether it is geographically or ecologically separated from another population.

microevolution

the small-scale changes resulting from genetic adaptation, that are usually expressed as changes within a species rather than the formation of a new species. see INDUSTRIAL MELANISM.
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On the other hand, Ayala (2005) agreed with the thesis that macroevolutionary principles are not reducible to microevolutionary approaches.
Finally, it should be noted that the use of conditional lethals, while allowing observation of a microevolutionary change within a manageable period, may also unintentionally create or reinforce a belief that selection primarily occurs in gross mutants and in short time frames.
Many creationists will accept microevolutionary changes within species as legitimate.
Microevolutionary processes under natural conditions are usually subtle and often complex, but can be dramatic under artificially strong selection pressures, such as antibiotic resistance in bacteria, or breeding for a certain phenotype in plants and animals.
46) However, design theorists generally would agree that evolutionary theory is best applied to account for small-scale microevolutionary changes rather than the origin of higher taxa and complex biological features.
Instead of a Designer stepping in to fill the void with engineered novelty, the fossil record clearly shows only a long procession of grubby microevolutionary speciation based on the straggle of surviving fauna.
Models of colonization and replacement based on skeletal morphology tend to demarcate populations geographically, and give little attention to microevolutionary processes .
Also, variation in resistance between individuals within populations, and between populations of Asian rodents, is evidence of potential and actual microevolutionary response.
34) (Janzen 1993a) which, if accompanied by strong linear selection as documented in this study, could lead to a substantial microevolutionary response (Lande and Arnold 1983).
In the second place, most of the organisms that colonize the high mountain follow opportunist strategies, with high rates of reproduction and of mortality, and their short generations follow each other in rapid succession, thus accelerating microevolutionary processes.
These include a focus on (1) gender-defined transmission pathways (allowing nuclear and cytoplasmic genomes to be viewed in analogous fashion and also serving to equalize mean effective population sizes and expected allelic coalescence times across these genomes), (2) genealogical structures in populations isolated by distance as well as vicariantly sundered over microevolutionary times, and (3) the statistical sampling properties of multiple genealogical pathways.
Further microevolutionary and population genetic approaches could enable the study of patterns of species adaptation and diversification, and set the genus Helianthemum as a Mediterranean model system suited for testing relevant evolutionary hypotheses.