LAHS students decode the mysteries of biodiversity

Jane Ridgeway/Town Crier
Los Altos High student Devon Tompane, above, delicately transfers extracted DNA to an agarose gel for her class’s International Barcode for Life project.

From oak woodlands to lush riverbanks and dry chaparral shrublands, the Santa Clara Valley’s natural environment is home to a diverse array of flora and fauna – for now.

For scientists who study biodiversity, the effects of climate change and habitat destruction present an urgent problem, according to Los Altos High School science teacher Meghan Strazicich. Only a fraction of plant and animal species have been discovered, identified and scientifically classified. If only a handful of experts are doing this identification work, the rate of species extinction may outpace that of scientific discovery.

“With traditional classification, it’s a very long, time-consuming process,” Strazicich said. “By the time we’re able to classify all living things that we can, they’re starting to go extinct.”

To solve the problem, you need a dedicated corps of capable scientists collecting data. You need high-level equipment. And you need to get your hands – on field collection days, quite literally – dirty.

You need Los Altos High students, it turns out.

The citizen scientists of Strazicich’s Biotechnology class at Los Altos High, together with Greg Stoehr’s AP Environmental Science class, have devoted their spring to hands-on science with real-world consequences as participants in the International Barcode of Life project.

Through DNA barcoding, the classification process becomes faster, Strazicich said, helping to identify species before they’re gone.

“The idea here is that citizen scientists help to catalog all living things on Earth to determine how they’re connected to each other,” she said, “and to help conserve species once we understand how they’re connected.”

DNA deep dive

In the field, Biotechnology students take plant and insect samples, extract the DNA and send it to Cold Spring Harbor Laboratory for sequencing. The resulting nucleotide sequence acts as a barcode, just like one on a product in a store, which can be used to identify each unique species. The class then dives deep into a public database of known DNA sequences to classify their specimens and add their own information about where the samples were collected.

Meanwhile, AP Environmental Science students use a sophisticated array of probeware to evaluate the sites where each specimen was found, recording everything from air quality to levels of light and shade.

It’s the confluence of the two classes’ work, Stoehr said, that produces particularly interesting results, capturing a snapshot of the environmental conditions that allow local species to thrive.

“Students measure environmental data, and layering that on top of species findings makes the connection between environment and biodiversity,” he said.

It’s a science lesson rooted in biology, human impact on the environment, genetics, chemistry and evolution, but it’s also a concrete contribution to the scientific community, one that produces data working scientists will actually use.

Learning is different, Stoehr said, when it has a real scientific impact, and projects aren’t just turned in to a teacher, graded and forgotten. His students, he noted, are getting a glimpse of what the day-to-day work of a professional scientist actually looks like.

“This is what science really is – taking unique data that will exist for that moment in time,” he said.

The real-world stakes not only make the project engaging, Stoehr added, but also intellectually challenging, driving home the importance of good methodology.

“They have to be more precise about their data collection,” he said, “because the data they get is what they’ll send in (to the laboratory). They have to be more meticulous and critical, thinking: ‘Where do I take the data? Is this the proper place? How long do I hold the probe up?’”

As recipients of an Innovation Grant from the Mountain View Los Altos High School Foundation, Stoehr and Strazicich have been able to equip their students with the same probeware and reagents used in college-level classes, ensuring that the data they contribute to the DNA barcoding database are reliable.

While students are learning specific scientific skills, such as how to perform gel electrophoresis or extract DNA from a sample, the big picture matters, too. They’re learning about the world they live in – about life itself.

According to the Consortium for the Barcode of Life, scientists have used data like that Los Altos students are producing for a wide range of practical applications, from uncovering the illegal sale of endangered species as meat to learning about the origins of life from species buried under permafrost. Other barcoding research has focused on revealing fraudulent herbal remedies, working to contain disease spread by certain species of mosquito and even identifying centuries-old specimens from natural history museums.

For more information on the International Barcode of Life project, visit

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