Phenotypic plasticity

From CreationWiki, the encyclopedia of creation science

Phenotypic plasticity is variation within an organism's genotype when the change is not fully controlled by genes alone but rather when environmental factors play a significant role and are the trigger mechanism for such. The term was originally put forth as a descriptor for morphogenesis of structures but is now more generally applied to include the changes that occur during the adult life of an organism.

Observation and Experimentation

Phenotypic plasticity can be seen in many different organisms but one specific case is in regard to the Drosophila melangasterine in which abdominal pigmentation in the female changes. These changes are seen to be the result of environmental fluctuations in temperature and light. Findings were recently published in the peer-reviewed journal PLoS Genetics in February of 2007 in a paper titled, Phenotypic Plasticity in Drosophila Pigmentation Caused by Temperature Sensitivity of a Chromatin Regulator Network.

What is expanded on and detailed in the paper is the specific homeotic gene that is called Abdominal-B (Abd-B). It is shown to be a major factor in the plasticity of pigmentation in the posterior abdomen. Abd-B is a cause for both light and dark melanin production within the Drosophila through disruption of the regulation of several pigmentation enzymes. What results are exploited genes by temperature which effects the regulation of chromosome architecture thus the observation is seen as either a dark colored or light colored abdomen. ^[1]