WHAT’S LIVING DOWN THERE?

“Orconectes virilis”, crayfish, with light- to olive-brown body color.
Kids are fascinated with what’s living beneath the water’s surface — oceans, rivers and lakes — spending endless hours exploring. Trying to identify creatures can be difficult as their features may vary with age, sex and even the environment. Experts rely on color and other traits to identify and classify organisms, but on occasion, species look so similar that even professionals can’t tell them apart. That’s why, as of 2013, scientists have included a new laboratory test to verify species identity, called DNA barcoding.

Gorham High School student loads an electrophoresis gel to analyze DNA.
Over the past year, Gorham, Westbrook, and Deering High School students used this technology to identify plants and animals collected from their regions. Each student extracted DNA from their specimen, used biotechnology to amplify and sequence a target gene, and then submitted the sequence to a genetic database for a comparison. This DNA barcode confirms the identity of the organism as well as evolutionary relationships to other species. The BoldSystems database stores more than 5 million barcodes from around the globe, including GPS coordinates and specimen images.

“Luxilus cornutus”, aka common shiner.
In the end, Maine students accurately identified many organisms from their regions and many contributed voucher (or reference) specimens to the genetic library of species living today (Maine Barcode of Life).
Imagine how useful this technique would have been to Charles Darwin as he examined the many varieties of beetles, birds, and barnacles!