South SFV Today

As many as 100 billion lifeforms, roughly the number of people who have ever lived on Earth, can be found in a liter of seawater. These microscopic organisms, collectively known as plankton, form the foundation of a global food chain, produce about half the oxygen we breathe, and sequester massive amounts of atmospheric carbon for thousands of years. Despite their significance, they remain scientific mysteries due to high research costs and erratic funding.

Stanford bioengineer Manu Prakash aims to reveal the secret lives of plankton and harness their powers. He leads an international team developing innovative, low-cost tools such as a rotating microscope and an easy-to-use plankton sampling process to enable citizen scientists to contribute to ocean health and biodiversity research.

“The ocean is a life-saving technology – Earth’s heart and lungs – but our perception of what it does is so primitive,” said Prakash. “You cannot fix what you don’t understand. Observation is the most fundamental tool scientists have for understanding.”

Prakash's passion was ignited during his first boat trip eight years ago when he encountered bioluminescent plankton glowing in the open ocean's silent darkness. “You kind of realize how small you are compared to this planet,” he said.

To realize his vision for new observation tools, Prakash has assembled a multidisciplinary team from fields including machine learning, computer science, fluid mechanics, cell biology, biochemistry, architecture, optics, physics, oceanography, visual arts, and traditional tool making. The goal is to build long-term data sets on plankton migrations and map future behavior based on predicted ocean conditions.

Prakash’s team created Planktoscope with support from PlanktonPlanet. This initiative engages citizen scientists in designing and deploying low-cost instruments to study plankton and share findings in public databases. Using simple sampling processes tested by 20 crews of "planktonauts," they built a planetary dataset showing which organisms are present where.

The PlanktoScope platform allows citizen scientists to analyze samples themselves using an open-source imaging system that matches commercial instrument quality at a fraction of the cost. It has demonstrated its capacity through over 20 oceanic voyages collecting data from diverse marine environments.

In addition to distributing more than 150 Planktoscopes worldwide for various applications such as monitoring coastal aquaculture in California or detecting harmful algal blooms in Indonesia, Prakash’s lab developed another innovative tool: a vertical tracking microscope based on a "hydrodynamic treadmill." This device simulates ocean depths within a circular chamber to observe plankton migrations continuously.

With funding from Stanford Doerr School of Sustainability’s Oceans Department and Stanford Woods Institute for the Environment's Big Ideas for Oceans program, Prakash is developing ways for this rotating microscope to recreate changing ocean characteristics like light intensity and water temperature.

“We will create and emulate every single parameter that plankton can perceive,” Prakash said. “That's really the magic of technology.”

Prakash envisions autonomous versions of these tools available via satellite so students globally can control them remotely. His lab also plans an online dataset featuring video footage documenting behaviors across over a thousand aquatic species.

“There’s a lot of anxiety around ecosystem collapse," Prakash said. “Every time I’m depressed I think about the aesthetic beauty of the microscopic world... There’s hope because you see how powerful these tiny creatures really are."

This project received funding from Stanford Doerr School of Sustainability’s Oceans Department and Stanford Woods Institute for the Environment's Big Ideas for Oceans program.

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