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Stories from Sara Hashemi

Researchers weren't sure what drove some theropods, like T. rex, to evolve tiny arms relative to their body sizes.

Tyrannosaurus Rex and Other Terrifying Predatory Dinosaurs Had Itty-Bitty Arms. Scientists May Have Finally Figured Out Why

A new study suggests that certain theropods—two-legged, mostly meat-eating dinosaurs—had shrunken forelimbs as an evolutionary trade-off for their strong skulls

A limestone pigeon sculpture from Cyprus, dated between 600 and 480 B.C.E.

Pigeon Bones Found at an Ancient Cyprus Settlement Reveal That Our Relationship With These Birds Began Earlier Than We Thought

Before common pigeons were considered urban pests, people domesticated them and relied on them for meat, fertilizer, messages and more. A new study suggests humans have lived alongside the winged creatures for at least 3,400 years

Scientists carried out their experiments in the bacterium Escherichia coli. Cells of the species are artificially colored blue in this microscope image.

Scientists Used A.I. to Redesign a Microbe’s Machinery to Function Without a Key Ingredient of Life

Although the researchers did not create an entire cell that could function without a crucial building block, the findings represent a big step in synthetic biology and provide a glimpse at how Earth’s earliest organisms may have lived

A view of the landslide and tsunami aftermath a few days after the catastrophic events

A Sudden Landslide Triggered Alaska’s 2025 ‘Mega-Tsunami.’ Now, Scientists Have Identified Warning Signs to Predict Similar Events

Natural disasters like the one at Tracy Arm fjord, about 45 miles south of Juneau, could become more common as climate change alters frigid landscapes, according to researchers

The drug ensitrelvir, under the brand name Xocova, was recently approved in Japan as a post-exposure protection against Covid-19.

This Pill Can Prevent You From Getting Covid-19 After Exposure to the Disease-Causing Virus, According to a Clinical Trial

The drug showed promising results in an international study involving nearly 2,400 participants, and the U.S. Food and Drug Administration is expected to make an approval decision for it in June

Tuerkayana hirtipes, a true crab species examined in the study

When Did Crabs Evolve Their Iconic Sideways Scuttle? Scientists Traced It to a Common Ancestor That Lived 200 Million Years Ago

The findings suggest that their famous lateral movement evolved just once. It may have helped the animals rapidly spread and diversify because moving in two directions meant they could easily escape predators

A visitor washes his hands before entering a hospital in the Democratic Republic of Congo as part of Ebola prevention measures.

The Ebola Outbreak in Africa Was Declared a Global Health Emergency by the WHO. Here’s What to Know About the Rare but Severe Illness

The international health agency notes that the outbreak does not meet the criteria for a pandemic, and the U.S. Centers for Disease Control and Prevention says that the risk to the American public is low

Artist's reconstruction of newly described koala species. 

A Dimpled Koala Fossil Found in a Cave in Western Australia Revealed Why This Previously Unknown Species Went Extinct

The new study found that they lost their arboreal habitat due to a drying climate, a dire warning for the modern-day marsupials that face a similar threat

The study focused on brain cell activity in a structure called the hippocampus, which is important for memory and learning.

Is the Unconscious Mind Aware of Its Surroundings? New Research Suggests Anesthetized Brains Can Process Overheard Words

Seven participants had electrodes temporarily implanted in a brain structure important for learning. While anesthetized, their nerve cells learned to differentiate between distinct sounds—and could even predict upcoming words in phrases

The Bering Strait is a narrow waterway between Russia and Alaska that connects the Pacific and Arctic oceans.

Could Building a Dam Across the Bering Strait Save the Planet From Some Effects of Climate Change?

A preliminary study suggests that blocking off the waterway between Russia and Alaska could help the survival of a key system of ocean currents. But there could be potential unforeseen consequences, particularly to marine ecosystems

Scientists used acidic and basic solutions to trigger chemical reactions in algae.

These Marine Algae Glow When Waves Disturb Them. Their Bioluminescence Could Power Electricity-Free Lamps of the Future

The single-celled organisms usually shimmer for mere milliseconds, but researchers figured out how to sustain their illumination. The technology could one day be used to light robots’ ways in the deep sea or space

Microplastics are particles smaller than five millimeters in length, or narrower than a pencil-tip eraser. 

Microplastics Are Swirling Around in the Atmosphere, Where They Might Be Contributing to Climate Change

Airborne plastic particles, particularly colorful ones, absorb more sunlight than they reflect, which can heat the surrounding air, according to a new study

Researchers studied social learning in the birds by introducing a novel food item: colorfully dyed almonds.

Wild Cockatoos Learn Which Snacks Are Safe to Eat by Copying Their Friends, New Research Suggests

Munching on the wrong items can lead to illness, but social learning might help the birds avoid making a potentially deadly mistake. The phenomenon could help explain why certain cockatoos have fared so well in urban environments

Chonkers, a Steller sea lion, is much larger than his companions, California sea lions.

Chonkers the Massive Sea Lion Drew Crowds to San Francisco’s Famed Pier 39. Then, a New Chunky Showstopper Stole His Identity

The Steller sea lion was an unusual visitor to the pier, which typically hosts smaller California sea lions. However, he may have moved on days ago, during which time a humongous member of the area’s more common species tricked onlookers

Members of the rescue team on a barge that later transported the whale to the North Sea

Timmy the Whale Was Released Into the North Sea After Being Stranded Off the German Coast for Weeks. Was That the Right Call?

The humpback whale first entered shallow water at the end of March, but its health deteriorated over the past few weeks. Experts have criticized efforts to rescue the animal, which may have done more harm than good

Lung cancer cells, shown in green, growing in a mouse heart

Cancer Is Somehow Rare in the Heart. Turns Out, the Organ’s Rhythmic Beat Might Keep the Disease at Bay, a Mouse Study Finds

Less than 1 percent of cancers start in the heart, and disease that begins elsewhere seldom spreads to the blood-pumping organ. New research suggests mechanical force might have a protective role

The Eta Aquarids as seen from Sri Lanka in 2024

The Eta Aquarid Meteor Shower Peaks This Week, but a Bright Moon Might Spoil the Show

This annual event, which peaks on the night of May 5 into the next morning, comes from the trail of debris left by Halley’s comet. It’s best viewed from the Southern Hemisphere, but skywatchers in the north can catch a glimpse

Cattle are a major driver of methane emissions.

Why Do Cows Burp Up So Much Planet-Warming Methane? A Newly Discovered Structure in Their Gut Microbes Could Be a Culprit

The “hydrogenobody” is an organelle inside certain microorganisms that live in a special stomach chamber in cattle, sheep and goats, according to a new study

Study author Gregory Bonito collects truffles in Australia. 

Australia Has a Surprisingly Successful Truffle Industry. This New Study Could Explain Why

Researchers examined hundreds of soil samples to uncover why the expensive fungi are thriving in the country

Left to right: Ethiopia's Yomif Kejelcha placed second, Kenya's Sabastian Sawe placed first, and Uganda's Jacob Kiplimo placed third

Two Athletes Smashed a Marathon Milestone, Running 26.2 Miles in Under Two Hours. Here’s the Science Behind Their Achievements

An intense training regimen, good weather conditions, physiology and lightweight shoes probably played a role in their astounding performances during the London Marathon on Sunday

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