Scale Insects - An Overview

Walk up to any pine tree, pick one of the lower branches and look for these white sesame seed sized specks. The small, white, yellow tipped specks on the pine needles are the scale insects. You should be able to spot them within < 5 minutes, if you are not seeing them, try another branch or another tree. Pine sap may also be white but will have irregular shapes and will not have a yellowish tip (as above).

Rodger Gwiazdowski, a PhD student in both OEB and the Division of Entomology studies the evolution of the Pine-leaf Scale-insect that feeds on pine needles of pine trees all across North America. Pine scale insects are totally weird bugs, females shed their skin a few days after hatching, loose their legs, and never move again. They have no eyes or antennae and feed on plant juices through a drinking straw that comes out of the center of their body. As adults, Males look like small flies, however they go on to live for only 3 days and never feed as their mouths are fused shut. Pine scales reproduce both sexually (males and females) as well as parthenogenically (making clones from unfertilized eggs). As part of his work Rodger sequences DNA from scale insect specimens he has collected to see patterns of genetic variation across North America. He uses the DNA sequences in analyses to produce phylogenetic trees, which are branching diagrams depicting patterns of evolutionary relationships. Phylogenetic trees can help to understand how individual scale insects are evolutionarily related to each other as well as when, and how many times, parthenogenesis (clonality) has evolved in these insects. To collect specimens, Rodger has traveled from Florida to Alaska and 26 states in between as well as most states of Mexico and parts of Canada.

You can learn more about Pine-leaf Scale Insects, and help Rodger collect specimens through the website:
http://bcrc.bio.umass.edu/scalemail/
Contact Rodger