Everyone loves a good plankton, right?
A team of scientists at Oregon State University and the University of Miami have created a project that opens up for citizen scientists the vast – really, really vast – world of some not so vast beings: plankton.
The new project, called Plankton Portal, asks for the public’s help in characterizing and categorizing the plankton in about a million images taken underwater near California. The data will help scientists probe the still curious planktonic world, plumbing it for clues about what we can do to support these plants and animals – as well as everything that depends on them.
Indeed, plankton, despite the myriad intriguing ways in which “plankton” can be deployed as an insult, are not exactly small stuff.
The word “plankton” is derived from the Greek adjective “planktos,” or “wandering” (the noun form gives us the word for a celestial wanderer: "planet"). What unites all plankton is that none of them can swim well enough to fight a current. That means that plankton, small beings with no particular home, end up having a pretty big home: the planet’s water, and wherever its currents go.
Plankton drift up, down, and all about in fresh water and salt water, in ponds and pools, and in swamps and streams. Sum them up, and plankton are the largest reserve of biomass in the planet — scientists put the amount of plankton mass produced each year in the tens of billions of tons. That’s despite the trifling point that a single plankton is measured in millimeters or micrometers (1/1,000 of a millimeter), excluding some big outliers.
Plankton are often divided into two categories: phytoplankton and zooplankton, a distinction that roughly divides the group into plant plankton and animal plankton. Phytoplankton, productive little plants, accomplish about half of all the photosynthesis done on Earth, supplying up to 85 percent of Earth’s oxygen.
“Without plankton, there would probably be no complex life on Earth,” said Adam Greer, a PhD candidate at the University of Miami and a researcher on the project.
Phytoplankton, as the smallest of the plankton, are also at the all-important bottom of the food chain. At the next step up are zooplankton, a group of animals that it's hard to believe are relatives to each other. Perhaps the most famous of the bunch are gelatinous plankton: jellyfish, the globular, ocean sentinel that seems to have somehow bucked the plankton label and gone on to make its own name for itself.
The zooplankton group also includes an order of animals that eat jellyfish: siphonophores, which do a splendid job as masquerading as jellyfish but are in fact a collection of little individuals, called zooids, that have glopped together into what looks like a teeming collection of bubbles. Their ranks include the Portuguese man-of-war, the stinging animal with tentacles that can be as long as 165 feet.
“When people think about plankton they think microscopic organisms, bugs of the ocean,” says Jessica Luo, a PhD candidate at the University of Miami and a researcher on the project. “That’s not always true.”
But then other zooplankton really are small. There’s daphnia, the genus of translucent, balletic crustaceans that are often called “water fleas,” but are of no measurable relation to the pests/circus performers, and there are copepods, which often have one red eye in the middle of their heads. There are also zooplankton that are only so temporarily: larvae that graduate into mollusks or corals or fish.
Despite those differences, what zooplankton all share (besides poor swimming skills) is that they are all food for something else. Zooplankton are snacks for other, bigger zooplankton, or for small fish, big fish, or even whales, which are prodigious eaters of krill, a dainty zooplankton that looks like a shrimp, but also a bit like a hummingbird. Keep going up the food chain, and we arrive at the terrestrial animals plunking their mouths or beaks or claws or spears or rods or nets into the world’s water.
“Plankton support all of the life in the oceans,” says Ms. Luo. “Without plankton, there would be no whales, sharks, dolphins or seals – nothing.”
No wonder that Spongebob Squarepants’ nemesis, Plankton, packs a lot of world-destroying power into his diminutive build: plankton, bantam things, are really pulling their weight down in the water. And, at least among nonscientists, they don’t often get a lot of credit for it.
At least, not until now. The Plankton Portal project began in the fall of 2010, when the In Situ Ichthyoplankton Imaging System (ISIIS), an underwater robot at the Southern California Bight took all the images that now supply the portal. The robot, spying on the plankton in real time, offers a faster way to analyze plankton than using bongo nets, which have been deployed since about 1960 to scoop up samples, and it also does so without ruining the animals (nets often slice up a jellyfish), said Luo.
About a million images, taken over three days and over a distance of almost 70 miles, have been provided to Plankton Portal.
But what to do with all these images? A computer could be asked to match photographed shapes to the plankton shapes in its database, but it would also miss subtleties. For example, a jellyfish sprouting new, little jellyfish would be glossed over as just one jellyfish; the jellyfish babies would be filtered out as water garble, said Luo.
But a human – well, a human would notice a jellyfish popping off new jellyfish (one user did just that a couple days ago).
“It’s those small things that take a human eye – and a little bit of curiosity – that we’re interested in,” said Luo.
But, of course, humans are not quite as quick as is a computer. And, with a million images to investigate, and about 10 to 20 plankton per image, the team needs the public’s help.
“It’s the power of many,” says Robert Cowen, director of the Hatfield Marine Science Center at Oregon State University and the principal investigator on the project.
The team hopes to come up with a broad portrait of the area’s plankton, looking for details about when and where different plankton live, where they reproduce, which way they drift, and which predators or other life is nearby. The next step, Dr. Cowen says, is to understand what makes plankton-rich zones so appealing to the plants and animals and, next, to marshal efforts toward keeping those hot spots just as they are.
Collecting plankton data is becoming all the more important, since plankton, vulnerable to changes in water temperature and comfortable within just a small pH range, are a telling barometer of the ocean’s health, says Cowen. Already, data has shown that plankton are winding up a higher latitudes in search of cooler waters, or are booming in number earlier or later in the year, he said. Those changes could spell trouble for the animals that feed on plankton, if their breeding and migration cycles do not also change, he said.
“It’s a fairly insidious problem,” he said.
Plankton portal is hosted on Zooniverse.org, the citizen-science interface that launched in 2007 with Galaxy Zoo and now has 18 projects, offering almost 900,000 budding scientists the chance to trundle through their favorite fields – be it climate science or planetary science – and to play in the big leagues: to date, 54 scientific papers have been published based on Zooniverse’s crowd-sourced data.
About 1,400 plankton enthusiasts signed up for Plankton Portal in the first 48 hours after the program launched this week, said Cowen. Users first run through a tutorial on how to participate: draw a line that measures the plankton’s length, then its width. Next, what sort of head does this plankton have? Is it buglike? Jellyfishlike? Now, what species is it? Medusa? Rocket Ship Thimble? Corn Cob?
Once that’s done, bam: Welcome to the planktonic field. It’s a big place.