The stickleback fish is an ideal organism for studying evolution in action, because there are many natural populations around the world and they display much variability in their features.  Researchers at HudsonAlpha have participated in an international collaboration to look for changes in DNA sequences which result in new or altered body features in the threespine stickleback fish.  The scientists found that changes not in a gene itself, but in a sequence which regulates a specific gene’s expression, led to the partial or complete loss of pelvic structures in separate fish populations across the globe.  This is an important contribution to an ongoing discussion about the nature of evolutionary changes over time, based on alterations in an organism’s DNA.
 
Read the paper Adaptive Evolution of Pelvic Reduction in Sticklebacks by Recurrent deletion of a Pitx1 Enhancer below: