Concept
Version 8
Created by Boundless
Horizontal Gene Transfer
HGT within the aphid species
(a) Red aphids get their color from red carotenoid pigment. Genes necessary to make this pigment are present in certain fungi. Scientists speculate that aphids acquired these genes through HGT after consuming fungi for food. If genes for making carotenoids are inactivated by mutation, the aphids revert back to (b) their green color. Red coloration makes the aphids much more conspicuous to predators, but evidence suggests that red aphids are more resistant to insecticides than green ones. Thus, red aphids may be more fit to survive in some environments than green ones.
Source
Boundless vets and curates high-quality, openly licensed content from around the Internet. This particular resource used the following sources:
"OpenStax College, Perspectives on the Phylogenetic Tree. October 16, 2013."
http://cnx.org/content/m44593/latest/Figure_20_03_02.jpg
OpenStax CNX
CC BY 3.0.