High-energy ion collisions have produced the swirliest fluid ever discovered, in a state of matter that mimics the early universe.

To create the überwhirly liquid, scientists slammed gold ions together at velocities approaching the speed of light at Brookhaven National Laboratory in Upton, N.Y. Such collisions, performed in Brookhaven’s Relativistic Heavy Ion Collider, cook up an ultrahot fluid, re-creating the state of the universe millionths of a second after the Big Bang, before protons and neutrons had formed. In this fluid, known as a quark-gluon plasma, the constituents of protons and neutrons — quarks and gluons — intermingle freely (SN: 12/10/16, p. 9).

Scientists already knew that this fluid is the hottest ever produced in a laboratory, and that it has almost no viscosity. Now, physicists can add one more unusual property to the list. The quark-gluon plasma created in such collisions has an average vorticity — or swirliness — of about 9 billion trillion radians per second, researchers from the STAR Collaboration report online January 23 at arXiv.org. That’s vastly more than other known fluids. Even the core of a supercell tornado has a vorticity of only 0.1 radians per second.

To measure vorticity, the scientists studied a quantum mechanical property called spin from particles produced in the collision known as lambda baryons. The spin, an intrinsic type of angular momentum, tends to align with the vorticity of the fluid, providing a window into the plasma’s gyrations.

African penguins have used biological cues in the ocean for centuries to find their favorite fish. Now these cues are trapping juvenile penguins in areas with hardly any food, scientists report February 9 in Current Biology.

It’s the first known ocean “ecological trap,” which occurs when a once-reliable environmental cue instead, often because of human interference, prompts an animal to do something harmful.

When juvenile Spheniscus demersus penguins off the Western Cape of South Africa leave the nest for their maiden voyage at sea, they head for prime penguin hunting grounds. But the fish are no longer there, says Richard Sherley, a marine ecologist with the University of Exeter Environment and Sustainability Institute. Increased ocean temperatures, changes in salinity and overfishing have driven the fish eastward.
Penguins are doing what they’ve evolved to do, following signs in the water to historically prosperous habitats. “But humans have broken the system,” Sherley says, and there’s no longer enough fish to support the seabirds.

Sherley estimates that only about 20 percent of these African penguins survive their first year, partly because they can fall into this ecological trap.
Ecological traps have been documented on land for decades. There has been a lot of speculation about traps in the ocean, but this study is the best evidence so far, says Rob Hale, an ecologist with the University of Melbourne.
“Hopefully the study will generate more interest in examining ecological traps in the ocean so we can better understand when and why traps arise, how they are likely to affect animals, and how we can go about managing their effects,” Hale says.

This trap may have occurred because of how penguins find their food. Researchers think penguins can sense a stress chemical that phytoplankton release when being eaten. Penguins eat sardines, which eat phytoplankton. Usually the chemical, dimethyl sulfide, signals to penguins where the fish are feasting on phytoplankton. But phytoplankton can release the compound in other situations, like in rough water. The signal is still sent, but there are no fish.

“You have a cue that used to signal high quality in an environment, but that environment has been modified by human action to some extent,” Sherley says. “The animals are tricked or trapped into selecting a lower quality habitat because the cue still exists, even though there’s high quality habitat available.”

Adult penguins have adapted to the trap and shifted their hunting patterns to follow the fish east. Sherley says they’re not sure how adults learned to avoid the problem, but that there must be a way that juveniles who survive to adulthood also adapt.

Researchers also tracked juvenile penguins from the Namibia and Eastern Cape of South Africa breeding regions. The eastern penguins have been unaffected by the trap because the fish have moved closer to them. The Namibia population is being barely sustained by the goby, a junk food fish that appears to be taking over the areas previously inhabited by sardines and anchovies.

The Western Cape penguins have been most affected. The population has declined 80 percent in the last 15 years — from 40,000 breeding pairs to 5,000 or 6,000, Sherley says. He estimates that if juvenile penguins hadn’t been falling victim to this trap, the Western Cape population would be double its current levels.

If the loss of fish off the Western Cape of South Africa can’t be reversed, Sherley speculates the two most likely outcomes are an African penguin extinction or an ecosystem shift. Current penguin conservation efforts protect penguin breeding areas, but the study suggests that the protections may be insufficient because the ecological trap is far from the breeding grounds.

Short bouts of suffocating conditions can desolate swaths of seafloor for decades, new research suggests. That devastation could spread in the future, as rising temperatures and agricultural runoff enlarge oxygen-poor dead zones in the world’s oceans.

Monitoring sections of the Black Sea, researchers discovered that even days-long periods of low oxygen drove out animals and altered microbial communities. Those ecosystem changes slow decomposition that normally recycles plant and animal matter back into the ecosystem after organisms die, resulting in more organic matter accumulating in seafloor sediments, the researchers report February 10 in Science Advances.
Carbon is included among that organic matter. Over a long enough period of time, the increased carbon burial could help offset a small fraction of carbon emitted by human activities such as fossil fuel burning, says study coauthor Antje Boetius, a marine biologist at the Max Planck Institute for Marine Microbiology in Bremen, Germany. That silver lining comes at a cost, though. “It means your ecosystem is fully declining,” she says.

“We need to pay more attention to the bottom of the ocean,” says Lisa Levin, a biological oceanographer at the Scripps Institution of Oceanography in La Jolla, Calif. “There’s a lot happening down there.” The new work shows that scientists need to consider oxygen conditions when tracking how carbon moves around the environment, says Levin, who was not involved in the research.
Some oxygen-poor, or hypoxic, waters form naturally, such as the suffocating conditions caused by a lack of churning in the deep realms of the Black Sea (SN Online: 10/9/15). Other regions lose their oxygen to human activities; fertilizer washing in from farms nourishes algal blooms, for example, and the bacteria that later decompose that algal influx suck up oxygen. Rising sea-surface temperatures could worsen these problems by decreasing the amount of dissolved oxygen that water can hold and making it harder for ocean layers to mix, as warmer waters remain on top (SN: 3/5/16, p. 11).
Scientists have noticed increased carbon burial in hypoxic waters before. The mechanism behind that increase was unclear, though. Boetius and colleagues headed out to the Black Sea, the world’s largest oxygen-poor body of water, and studied sites along a 40-kilometer-long stretch of seafloor. (Military activities in the region following Russia’s annexation of Crimea limited where the researchers could study, Boetius says.) Some sites were always flush with oxygen, some occasionally suffered a few days of low oxygen, and others were permanently oxygen-free.

The ecological difference between the sites was stark. In oxygen-rich waters, animals such as fish and starfish flourished, and little organic matter was deposited on the seafloor. In areas with perpetually or sporadically low oxygen, the researchers reported that oxygen-dependent animals were nowhere to be seen, and organic matter burial rates were 50 percent higher.

Bottom-dwelling animals are particularly important, the researchers observed, helping recycle organic matter by eating larger bits of debris sinking from the surface ocean and by mixing oxygen into sediments during scavenging. What’s more, the researchers found that the microbial community in oxygen-poor waters shifted toward those microbes that don’t depend on oxygen to live. Such microbes further limit decomposition by producing sulfur-bearing compounds that make organic matter harder to break down.

Depending on the size of the area affected, animals could take years or decades to return to previously hypoxic waters, Boetius says. Some of the studied sites experienced low-oxygen conditions for only a few days a year yet remained barren even when oxygen returned. The absence of animals prolongs the effects of hypoxic conditions beyond the times when oxygen is scarce, she says.

BOSTON — For the first time since the Viking missions to Mars in the 1970s, NASA is making the search for evidence of life on another world the primary science goal of a space mission. The target world is Jupiter’s moon Europa, considered possibly habitable because of its subsurface ocean.

The proposed mission, which could be operational in the next two decades, calls for a lander with room for roughly 43 kilograms of science instruments. They include a robotic arm to scoop samples and others to analyze the chemistry of the Jovian moon’s icy surface (SN: 5/17/14, p. 20). “It’s the first time in human history that we have the ability to design instruments to detect life within our own solar system’s backyard in the next 20 years,” astrobiologist and planetary scientist Kevin Hand said February 17 at the annual meeting of the American Association for the Advancement of Science. Hand’s team submitted a 264-page report describing the potential mission to NASA on February 8. The report is now open for review by the scientific community.

A major concern is taking precautions to prevent contamination of Europa by microbes from Earth. “These are important for protecting Europa for Europans,” said Hand, who works out of NASA’s Jet Propulsion Laboratory in Pasadena, Calif. His team proposes baking the spacecraft to kill as many microorganisms clinging to the exterior of the lander as possible.

Decontamination precautions are important not only for protecting the life that’s on the world being explored, notes biologist Norine Noonan of the University of South Florida St. Petersburg. They are also important for the science goals of the potential mission. “You don’t want to send a $2 billion spacecraft somewhere to discover E. coli,” Noonan says.