21 May 2026

Today’s Visualized takes a look at a curious coral reef robot. But first, catch up on the latest science news, including the twists and turns of Himalayan rivers and how a startup is giving ‘dead’ brains a fresh boost.

river dynamics | Science

Climate change gives rivers wanderlust

High in the Himalayas, a system of rivers and glaciers known as the “Water Tower of Asia” supplies freshwater to roughly two billion people downstream. Scientists who examined 40 years of satellite imagery from three major river basins—the Yarlung Tsangpo, Indus, and Ganges—observed that, due to climate change, the waters there have started wandering more.

As rivers flow, they rarely follow a straight path, curving in different directions and forming bends called meanders. Since water erodes the outer bank over time and deposits sediment on the inner bank, those bends move across the floodplain and the river shifts sideways, in a “meandering migration.” Researchers found that, in the Himalayas, rates of lateral channel migration nearly doubled between 1980 and 2020. Rivers also abandoned meandering loops, jumped channels, and changed patterns more often, drastically reshaping downstream ecosystems.

Scientists believe the changes are caused by the thawing and retreat of the region’s ice and frozen ground, a phenomenon known as “cryosphere degradation.” As temperatures in the upper Himalayas rise at roughly twice the global average rate, glacial melt accelerates, frozen ground thaws, and riverbanks lose the icy cohesion that once held them in place. This rise in meandering is part of a broader pattern, geophysical scientists Shawn Chartrand and Jonas Eschenfelder argue in an accompanying Science Perspective, noting that the dynamics of rivers in cold regions “ can be early indicators of environmental change under a warming climate.”

Read the Science Paper

Read the Perspective

drug development | Scienceinsider

Startup gives new life to disembodied brains

Photographed through a window, Bexorg scientist Luis Gonzalez checks a human brain maintained on life support. s. reardon/science

A day ago, the brain was in a living person. Now, hours after its owner died, it sits on a cart draped in tubes that quiver as they pump liters of blood substitute and other fluids through the organ. With most of its key functions intact but its electrical activity quenched by anesthesia, the brain hovers between life and death. As it metabolizes experimental drugs, sensors record its reactions, capturing hundreds of datapoints. After 24 hours, it will be sliced into hundreds of pieces for more detailed study.

The brain is one of more than 700 that the five-year-old biotech startup Bexorg has nurtured and studied using a set of proprietary brain-sustaining machines it calls BrainEx. The platform grants researchers an intimate look into how experimental therapies might work inside brains with neurodegenerative diseases such as Parkinsons, Alzheimer’s, or amyotrophic lateral sclerosis (ALS), potentially offering more reliable results than lab animals or cells in a dish.

Bexorg has largely stayed under the radar, but now the company is scaling up and inviting new attention. Its new lab space, which Science visited last week, will slice up and analyze 1600 brains per year. At a media event this week, the company showcased its assembly line process—and sought to reassure the public that its disembodied brains don’t cross ethical lines or risk regaining consciousness. Meanwhile, the pharmaceutical company Biohaven is putting insights from these brains to the test, launching a clinical trial of a drug meant to boost energy supplies in ailing brains based, in part, on data gathered using BrainEx.

Read the Full Story

SPONSORED

Rethinking aging outcomes through immune system biology

Immune aging shapes inflammation, resilience, and decline—but how should we measure its impact? Join Andrea Maier and Mitsuo Maruyama as they explore immunosenescence, intrinsic capacity, and emerging links between immune function, gut biology, and healthspan.

Visualized

This autonomous underwater robot would have found Nemo in no time. MCCAMMON ET AL./SCIENCE ROBOTICS (2026)

It isn’t hard to see why coral reefs, with their dazzling colors and teeming throngs of life, are often called rainforests of the sea. But just like tropical rainforests on land, these valuable ecosystems are increasingly under threat. Ecologists and conservationists have struggled to assess the biodiversity present in these habitats, since traditional reef surveys must be conducted by scuba divers and can be time-consuming, expensive, and possibly dangerous for the people involved.

What the field has needed is an explorer that can stay underwater for hours at time, collecting data over large distances and fearlessly navigating in complex reef environments all on its own. Now, scientists have built one.

Scientists send CUREE off on an expedition to Joel’s Shoal. MCCAMMON ET AL./SCIENCE ROBOTICS (2026)

The new autonomous underwater vehicle (AUV), described in Science Robotics, is equipped with high-resolution cameras, outstretched hydrophones, and powerful on-board computers, allowing it to gather visual and auditory information about coral reef environments and analyze it in real-time. The device—aptly named CUREE, for Curious Underwater Robot for Ecosystem Exploration—can detect biological activity using sound, then follow-up with close-up visual observations.

Together, these abilities allow CUREE to finely map out “hotspots” of biological activity within coral reefs, where large numbers of marine organisms tend to cluster for feeding, shelter, and reproduction. “We know that biodiversity on reefs isn’t distributed uniformly,” lead study author Seth McCammon said in a statement. “But until now we haven’t really been able to reliably quantify that by finding these patchy hotspots, mapping them at the centimeter scale, and measuring just how active they really are.”

The robot followed this barracuda for several minutes, like the Terminator pursuing Sarah Connor. MCCAMMON ET AL./SCIENCE ROBOTICS (2026)

Between 2022 and 2024, researchers deployed CUREE on three expeditions to a healthy reef in the U.S. Virgin Islands known as Joel’s Shoal. The AUV consistently identified the same hotspot: the area around a large pillar coral, which provides a complex 3D environment for many fish species to find food and shelter. While in the water, CUREE counted fish and homed in on specific sounds, including the telltale crackle of snapping shrimp. On one occasion, the robot stalked a barracuda for nearly 300 meters as the predator visited different locations within the reef and faced off with a large reef snapper.

In the future, fleets of these autonomous robots could potentially explore reefs and discover new hotspots all over the world, guiding efforts to protect these habitats from the stress of warming oceans, disease, overfishing, and other threats. “Autonomous systems like this can help us find—and protect—the most vital parts of these ecosystems before it’s too late,” said principal investigator Yogesh Girdhar.

Read the Paper

Et Cetera

Political science

Microbiologist Jasmine Clark has won a Democratic primary election in Georgia, all but ensuring that she will become the first Black woman with a science Ph.D. to serve in the U.S. House of Representatives.

Read more at ScienceInsider

Apocalypse moon

Neptune’s moon Nereid may have gained its unusual orbit during a chaotic encounter with Triton, the planet’s largest moon, that clobbered the rest of its siblings.

Science Advances Paper | Read more at Science News

A leg up

A wearable robot helps improve knee function in children undergoing gene therapy for spinal muscular atrophy, boosting strength and mobility.

Nature Paper | Read more at Nature

The main results can be simplified into one word, which is empathy
—Xabier Simón Martínez-Goñi, University of Essex

CAREERS | 20 May 2026 | katie langin

A new preprint reveals what 2600 early-career researchers say are the traits of an ideal supervisor.

Last but not least

This International Tea Day, I’m looking for the perfect snack to accompany my afternoon cuppa. Scientists have apparently figured out the best way to make a chocolate chip cookie, but I’m also intrigued by the prospect of 3D-printed cake.

Phie Jacobs, General Assignment Reporter, Science

With contributions from Ana Georgescu and Kelly Servick

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