19 May 2026

In today’s Logbook, your friendly neighborhood General Assignment Reporter tells a tale of two seals. But first, catch up on the latest science news, including some inhabitants of the ocean’s mysterious hadal zone and implantable “living materials” made of engineered bacteria.

oceanography | Science

Tiny critters thrive on rocks in deep-sea trenches

This protist, which scientists recovered from a deep ocean trench, contained dozens of pine pollen grains in various stages of digestion. song et al./Science (2026)

The ocean’s mysterious hadal zone, which lies within trenches between 6000 and 11,000 meters down, is one of the least explored habitats on the planet. Recent studies have demonstrated that this abyss is home to a remarkable diversity of life, which manages to thrive despite crushing pressures and frigid temperatures. But many of these organisms, particularly those that are permanently attached to hard, rocky substrates, remain difficult for scientists to sample.

To investigate these deep-sea communities, researchers aboard the Chinese submersible Fendouzhe descended into the darkness of the Kermadec and Mariana trenches. As the team reports in a new study, collected rock samples revealed 32 species, mainly consisting of single-celled organisms called protists, most of them new to science . The team did find some larger fauna, including two sea anemones, a carnivorous sponge, and a marine worm. But the vast majority of the observed critters were millimeter-sized and living in a variety of dense formations on rock surfaces, from tubes and chains to large mats. Some organisms were slender and sparsely branched, while others had tiny, bead-like chambers. One flat, encrusting bryozoan was so transparent that it only became visible once the rocks dried.

Researchers have previously assumed that these organisms get their energy from inorganic chemicals, so the study authors were surprised to find that many of their sampled specimens appear to feed on organic matter. Some have a diet consisting of pine pollen grains, which are transported from the land by wind and ocean currents before settling in trenches. As a result, the team reports, similar communities of organisms living on rocky substrates may represent “a previously unrecognized carbon hotspot in hadal environments.”

Read the Paper

biomaterials | Science

Pockets of engineered bacteria fight infection from the inside

So-called “living therapeutics” containing synthetically engineered cells have the potential to revolutionize medicine. When implanted inside the body, these cells could theoretically sense disease-related changes, such as inflammation or infection, and immediately dispense drugs. Bacteria, which can be genetically tweaked to release therapeutic molecules in response to biological signals and thrive in a huge variety of human tissues, are ideal candidates. There’s just one problem: Once introduced into the body, these microbes don’t tend to stay put.

Now, the researchers behind a new study have found a way to keep bacteria contained. As lead author Tetsuhiro Harimoto explained to Science Podcast host Sarah Crespi, developing a scaffold material that would allow the bacteria to do their job but still be stiff enough to withstand the pressure created by a growing colony wasn’t easy: “ We would literally see these materials crack open, and the bacteria would burst out .” The team eventually landed on a hydrogel, with droplets of bacteria-filled gelatin embedded inside a scaffold made of polyvinyl alcohol; it remained intact for up to 6 months in culture. When implanted into the joints of mice, the genetically engineered bacteria within the hydrogel successfully detected chemical signals from Pseudomonas aeruginosa—a common cause of infections related to artificial bone and joint replacement. The implanted microbes autonomously self-destructed in response, releasing antibacterial proteins that killed off the pathogen.

As biomedical engineers Kaige Chen and Quanyin Hu wrote in a related Science Perspective, the approach treats the scaffold “as an active determinant of whether contained bacteria can function safely over time,” rather than a passive vehicle. “This reframing brings living therapeutics closer to a model in which long-term, in vivo embedded therapeutic function replaces repeated drug administration.”

read the SCIENCE PAPER | listen to the Science Podcast

Read the Perspective

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logbook

A Mediterranean monk seal snoozes on the sea floor within an underwater bubble cave. octopus foundation

For the love of monk seals

Phie Jacobs, General Assignment Reporter, Science

Earlier this month, a tourist hurled a rock at an endangered Hawaiian monk seal swimming in the water off the Lahaina, narrowly missing the animal’s head. Video of the incident, which had been captured on a bystander’s cellphone, drew widespread outrage on social media, and the tourist is currently facing criminal charges.

When the affair first hit the headlines, I was working on a story about Mediterranean monk seals, which, like their cousins in Hawaiʻi, are having their own problems with tourists. I didn’t know much about these animals before coming across the Oryx study that inspired the article , but it’s hard not to fall in love with them. As lead study author Joan Gonzalvo tells me, “It’s a very iconic species.”

But popularity has its downsides. Humans, many of them eager to catch a glimpse of the world’s rarest pinniped species, have driven these seals to hide out in increasingly remote habitats—including underwater “bubble caves” like the one pictured above. Unlike the tourist in Hawaiʻ i, most people usually aren’t deliberately trying to harm the seals. But their actions, even if they come from a place of genuine curiosity and appreciation, can still cause significant damage.

Scientists also need to take care when observing and monitoring animals in the wild, since human disturbance can alter the very behaviors they hope to study. That’s why study co-author Julien Pfyffer and his colleagues at the Octopus Foundation designed the fully autonomous camera system used in the new study, allowing scientists to observe seals and other wildlife over long stretches of time without bothering them. When installing the cameras, Pfyffer’s team took care to work quickly, replacing kits during periods when monk seals were less active, and allowing any animals that were present to become accustomed to their presence.

Monk seals “are very, very beautiful,” Pfyffer tells me, “but we need to keep our distance from them, and sometimes it’s not easy to make people understand that.”

Read the Full Story

Et Cetera

Monkey business

The CDC plans to retire more than 160 of its research monkeys to a private sanctuary in southern Texas, drawing criticism from some biomedical experts and the director of a leading primate sanctuary. “No one who cares about monkeys would propose this plan,” one critic told ScienceInsider.

Read more at ScienceInsider

Darling dingo

Nearly a thousand years ago, Aboriginal people in Australia cared for and deliberately buried a dingo. Skeletal analysis suggests the animal was tamed, and people continued to tend the burial site by “feeding” it with mussel shells for multiple generations.

Australian Archaeology Paper | Read more at The Guardian

Teach a Neanderthal to fish

New research suggests that Neanderthals were snacking on shellfish, even using sophisticated seasonal harvesting strategies, thousands of years before their human descendants.

PNAS Paper | Read more at Discover

With each hour, with each day, there’s a potential that this will expand.
—Jason Kindrachuk, University of Manitoba

NEWS FROM SCIENCE | 18 May 2026 | Kai Kupferschmidt

Scientists are racing to sequence a rare Ebola virus and begin clinical trials for candidate drugs, but the outbreak—which appears to have spread undetected for many weeks—continues to grow in the meantime.

Last but not least

I recently wrote a Future News all about the impact of scientific naming, so I can’t believe I missed the news about this bizarre-looking fish species named after a character from Sesame Street. I must say, the resemblance is uncanny.

Phie Jacobs, General Assignment Reporter, Science

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