While humans have three color cones in the retina sensitive to red, green and blue light, birds have a fourth color cone that can detect ultraviolet light. A research team trained wild hummingbirds to perform a series of experiments that revealed that the tiny birds also see combination colors like ultraviolet+green and ultraviolet+red.

Engineers have developed a comprehensive model of deep-seated landslides and demonstrated that it can accurately recreate the dynamics of historic and current landslides occurring under varying conditions. The model points to the temperature of a thin layer of clay at the base of the landslide as critical to the potential for sudden cataclysmic failure. The approach is currently monitoring a...

In one of the largest educational field experiments ever conducted, researchers found that promising interventions to help students complete online courses were not effective on a massive scale -- suggesting that targeted solutions are needed to help students in different circumstances or locations.

A new cell-free platform rapidly identifies optimal enzyme combinations for sustainable fuels and materials.

Ice melts in the Arctic Ocean were thought to be drawing large amounts of carbon dioxide out of the atmosphere, acting as a carbon sink and helping to mitigate greenhouse gases. But new research shows that may not be the case in all areas, particularly in the Canada Basin, where the carbon sink is shrinking, inhibiting the ocean's ability to absorb carbon dioxide from the atmosphere into the deep...

Older men who have a weak or irregular circadian rhythm guiding their daily cycles of rest and activity are more likely to later develop Parkinson's disease, according to a new study.

How could the planet be covered entirely in ice -- a state known as 'Snowball Earth'-- and still give rise to multicellular life? The transition to such icy periods may not have been as abrupt as previously thought, new research shows.

Scientists have developed molecules that can remodel the bacterial population of intestines to a healthier state. They also have shown -- through experiments in mice -- that this approach reduces cholesterol levels and strongly inhibits the thickened-artery condition known as atherosclerosis.

A survey of 1,000 outdoor education programs nationwide finds that nearly two-thirds are in danger of folding because of the COVID-19 pandemic. Such programs connect youth with the world around them and teach about nature, with documented academic, health and social benefits. But most programs are conducted by residential outdoor science schools, nature centers, parks and zoos, not in traditional...

Scientists have demonstrated a practical technique for controlling magnons, which could lead to computer chip switches that would use less energy and radiate less heat. The approach brings two important firsts: It can be built on silicon and operates efficiently at room temperature, meaning it might be more readily employed by computer manufacturers.

Mixing and matching computational models of 2D materials led scientists to the realization that excitons can be manipulated in new and useful ways.

The discovery of a tiny insect fossil in Western Canada is unearthing big questions about the global movement of animals across deep time. The fossil, estimated to be 50 million years old, is the latest in a pattern of discoveries that are leading experts to contemplate a Canada-Australia connection not previously considered.

Social media sites aren't the only things that keep track of your social network -- your brain does, too. But loneliness alters how the brain represents relationships.

Greater adherence to a variety of healthy eating patterns was associated with a lower risk of cardiovascular disease.

New research has revealed unexpectedly high growth rates for deep water photosynthetic corals. The study alters the assumption that deep corals living on the brink of darkness grow extremely slowly.

Transmission of COVID-19 from mother to baby during pregnancy is uncommon, and the rate of infection is no greater when the baby is born vaginally, breastfed or allowed contact with the mother, according to a new study.

A tuberculosis vaccine developed 100 years ago also makes vaccinated persons less susceptible to other infections. While this effect has been recognized for a long time, it is not known what causes it.

Picture 500 million cars stacked in rows. That's how much carbon -- about 1,000 petagrams, or one billion metric tons - -is locked away in Arctic permafrost.

A new risk prediction model for healthcare providers can forecast an individual patient's likelihood of testing positive for COVID-19 as well as their outcomes from the disease.

The brain and its surrounding blood vessels exist in a close relationship. Researchers have discovered how cells of the blood vessels sense the metabolic condition of the brain and alter vascular function in response. The result could be important for patients with neurodegenerative disorders such as Alzheimer's because the onset of these age-related diseases coincides with vascular defects and...

A new study attempts to shed light on triggers of post-trauma nightmare occurrences -- a topic that has received scant study.

Light exerts a certain amount of pressure onto a body: sun sails could thus power space probes in the future. However, when light particles (photons) hit an individual molecule and knock out an electron, the molecule flies toward the light source. Atomic physicists have now observed this for the first time, confirming a 90 year-old theory.

Researchers have established a cell culture that allows them to test antibody-laden plasma, drugs and drug combinations in the laboratory. A screen of 136 safe-in-human antiviral drugs and identified six promising candidates. One combination of two drugs was so effective that researchers hope others can begin clinical trials on the drugs now.

The group that previously studied Martian dust storms now shifts focus to the electrochemical processes resulting from dust storms that may power the movement of chlorine, which is ongoing on Mars today.