Professor Richard Emlet holds out a strange animal that looks like a cross between a gumboot and a helmet that’s almost imperceptibly curling up into a ball.
“Whoa! Look at this, guys!” he calls to his students. “It’s gumboot chiton. It’s like a big, very slow cow that eats some of the algae that you see on the rocks and they can roll up, almost like an armadillo rolls up.”
Emlet and his University of Oregon Institute of Marine Biology teaching partner Maya Watts are leading a class of undergraduates through a system of spectacular tide pools on southern Oregon’s Cape Arago.
“The animals are really magical,” Emlet says. “I mean they are really — They belong in ‘Harry Potter’ novels.”
Emlet’s referring not just to the fascinating ways creatures from sea stars to scale worms look, but also the novel ways they manage to survive in this extreme environment known as the intertidal zone. Unlike terrestrial or even marine animals, intertidal animals can spend half their lives under a cold bath of seawater and the other half exposed to air and sunlight.
“Nice!” exclaims Jackson Coles, one of Emlet’s students. Coles has a small scale worm that he’s found in the gills of the gumboot chiton wrapped around his fingertip. “I’m going to take tissue samples of him to send to the Smithsonian.”
The Smithsonian Institution has been collecting scientific specimens like these since 1846. And now this undergraduate class at OIMB in Charleston, Oregon, is adding to that venerable compendium and an online database called the Barcode of Life project.
“We’re collecting the whole organism, we’re collecting the little tiny piece of tissue for this DNA identification process and we’re collecting a somewhat bigger piece which is going into what’s a biorepository. And the idea with this biorepository is that it’s a piece of animal tissue which might be useful in the future for some as yet unknown purpose,” Emlet explains.
Emlet’s students collect a tissue sample from each organism – which is then extracted for a particular gene that serves as a “barcode.” These unique barcodes can be used to identify species and illuminate relationships between species.
“We’re effectively creating a library and the barcodes and voucher specimens are the books,” Emlet explains.
While DNA analysis emerged in the 1970s and ’80s, it wasn’t until the early 2000s that the notion of using specific or single genes for cataloging organisms really got rolling.
“Most of the procedures over the last centuries has been based on morphology — what does the animal look like, what do the parts look like, what’s their shape, how many do they have — that sort of thing,” explains Emlet.
The shift from an appearance-based to a DNA-based system shook up the world of scientific classification and revealed exciting new information.
“It’s opened up a whole new perspective on how we can consider the relationships between animals,” Emlet says, “and what that’s led to is a revolution in our understanding of who’s related to who.”
This emerging, new family tree is helping to show how organisms evolved over time and how diversity was generated from a few organisms to the wide array of organisms we have today, Emlet says.
The technology allows for the detection of very fine differences between species that might appear to be identical when classified based on the older system. Those minute distinctions allow scientists to look for additional differences that reveal that some “species” are actually collections of multiple species.
One example is the dog whelk — a snail formally known as Nucella emarginata — that was distributed along the West Coast from Alaska to California. With the distinctions revealed by barcoding, the species has been split into two species: now the northern species is Nucella ostrina and the southern one is Nucella emarginata, which appear to overlap somewhere in central California.
A similar investigation is currently going on with a keyhole limpet known as Diadora aspera that may, in fact, be two separate species.
The updated classifications and storage of specimen material will also allow scientists to see if biodiversity changes over time, and that has big implications for measuring the effects of climate change, among other things.
But today here in the tide pools, it’s the little things that matter.
“Oh, here’s a couple of nudibranchs guys. This is called the shaggy rug,” Emlet says, pointing out small pinkish blobs decorating a half-submerged rock to an assembly of students.
“This one?” laughs a student as she leans in.
“Both of them - see, there’s two- and they go around eating anemones.”
Nudibranchs (literally “naked lung”) are a group of shell-less snails that make up a whimsical realm that would fit right into a Harry Potter novel.
Dr. Watts finds a dorid nudibranch in a shallow pool.
“This particular type of nudibranch, they have something called a ‘branchial plume’ or an anal plume in the backend that surrounds the anus and that’s how they breathe.”
She can’t help chuckling as she explains that this secondary gill is “chemo-sensory, so they can kind of smell the water around them.”
Back at the institute’s labs, high-powered microscopes outfitted with photographic gear reveal details that aren’t visible to the naked eye. Student Aaron Henderson is seated at one of them, examining a segmented worm.
“These are called chaetae and they’re actually how the worm moves through the water column to find its host species,” he says, referring to the tiny appendages that line the worm’s sides like a series of tiny brooms.
Henderson snaps some macro photos of the top section of the worm, formally known as Halosydna brevisetosa.
The photograph files, along with the tissue samples and specimens for the biorepository, are packaged up and sent to the Smithsonian for archiving and DNA analysis. Once complete, all the details – including an actual barcode – are added to the Barcode of Life project’s database.
The website is available for almost anyone to access and though it contains a head-spinning amount of detail and technical information, even non-scientists can enjoy the super close-ups of the flamboyant fluff of a feather duster worm, or the feeding fingers of a fringed filament worm or the creepy ridges of a tunnel-tailed orbit worm.