A painting of the interior of a eukaryotic cell highlights a portion of the cell nucleus and the cytoplasm, where numerous mitochondria and bits of the endoplasmic reticulum are visible.

Could mitochondria be the key to a healthy brain?

By Diana Kwon  Some researchers suspect these bacterial ancestors living within our cells may contribute to a wide range of neurological and psychiatric disorders. Read more.

An impressionist painting showing a father crouched down, with arms outstretched, as a toddler attempts to walk toward him.

Evolution of the dad

By Elizabeth Preston  Most male mammals have little or nothing to do with their kids. Why is our own species different? Read more.

Collage shows people's hands using devices such as a phone or laptop in a virtual meeting, with an illustration of the planet superimposed on top.

Let’s keep meetings virtual after Covid

By Katherine H. Freeman and Raymond Jeanloz  OPINION: We don’t want to go back to living on planes and out of suitcases. Virtual meetings are cheaper, more accessible and better for the planet. Read more.

 

From the archives

Juneteenth, which commemorates the end of slavery in the United States, is now a federal holiday. For scholarly context on the ongoing racial inequities in America, explore Annual Reviews’ article collection and watch our video.

A curated collection of review articles that focus on understanding discrimination and its impact, and what must be done to end it. Read more.

Covid-19: Why race matters for health

VIDEO: The pandemic has highlighted the complex links between inequality, racism and disease risk in America. Harvard public health scholar David Williams explains. Watch now.

 

The delta variant — a fast-spreading version of the coronavirus that is more transmissible and more likely to send people to the hospital — has been designated a “variant of concern” by the CDC. Dr. Anthony Fauci provides context in an NPR interview with Leila Fadel. Learn more about how new strains emerge in our video with computational geneticist Pardis Sabeti or read our comic.

The changing coronavirus

Coronavirus evolving: How mutations arise and new variants emerge

By Diana Kwon Illustrated by Maki Naro  COMIC: As it spreads throughout the world, the virus that causes Covid-19 has been changing. Scientists are tracking those changes, hoping to stay one step ahead of worrisome strains. Read more.

 

What we're reading

Sickness sleuth  Despite modern medicine’s many successes, the causes of a startling number of ailments — be they respiratory infections, cancers or autoimmune disorders — remain mysterious. But infectious-disease researcher Joe DeRisi is on it. For the New York Times Magazine, Jennifer Kahn profiles DeRisi, whose feats include helping to identify the unknown illness that turned out to be SARS and pinpointing a tapeworm as the cause of a construction worker’s swollen brain. His latest project involves sampling blood from people all over the world, looking for unknown pathogens, and it’s already flagging viruses to monitor. Of one such primate virus that cropped up in samples from people with meningitis in Bangladesh, DeRisi says: “Maybe it’s dangerous, maybe it isn’t. But I’ll tell you what: It’s now on my radar.”

With flying colors  Morpho butterflies — with their striking, iridescent blue wings — are accomplished nano-engineers. Their blue hue comes from meticulously crafted nanoscale structures that scatter and interfere with wavelengths of light in ways that reinforce some colors and suppress others, writes Viviane Callier for Quanta Magazine. How critters throughout the animal kingdom build these nanostructures “is mind-blowingly not-understood,” one researcher says. Tracking down the answers may lead to improved light-based technologies.

Maybe this time  For decades, companies have tried to market the biodegradable plastics called polyhydroxyalkanoates or PHAs as alternatives to the long-lived plastics that are polluting the planet. Now that jurisdictions are banning single-use plastics such as straws and takeout containers, has the moment for PHAs finally arrived? For Chemical & Engineering News, Alexander H. Tullo profiles a company that’s betting on it, and covers the scrutiny, skepticism and stock market short sellers that have entered the fray.

 

Art & science

A top-down view of a large dome of white silk threads dotted with yellow silkworms; a person standing inside the dome is visible through the threads.

CREDIT: COURTESY OF NERI OXMAN AND THE MEDIATED MATTER GROUP / MIT MEDIA LAB

By design  Human-centered design incorporates the perspective of people — the ultimate users of a product or system — into every step of the creative process. But what if centering things on humans is precisely what we should avoid, asks scholar Tomasz Hollanek, who focuses on the intersection of design theory, technology ethics and critical AI studies. In PSYCHE, Hollanek explores work by designer Neri Oxman of the Mediated Matter group at MIT’s Media Lab, whose Silk Pavilion project exemplifies an approach in which humans are but one component.

Oxman’s group investigated cocoon production by the silkworm Bombyx mori, and then used a combo of experimental data and algorithms to make stunning silk structures. In one phase of the project, shown above, some 1,500 silkworms are spinning away atop the pavilion’s scaffolding, filling in gaps between machine-spun threads. Oxman’s approach and process, writes Hollanek, yield opportunities “to envision new forms of creative coproduction and coexistence between species. Human making has had an unprecedented impact on the planet,” he notes, “but we’re not the only makers out there.” To see a completed pavilion, read Hollanek’s piece on allocentric design.