Animals consistently show fear when people pose a direct lethal threat, such as through hunting or fishing. Their reactions to non-lethal human activity, however, are much less predictable.

How Wildlife Responds to Human Threats

The meta-analysis, published in Ecology Letters, brought together three decades of research examining how wild animals alter their behavior around humans. The researchers compared changes in feeding, vigilance, and movement across many species and ecosystems to determine whether people are always perceived as an extreme danger.

“The short answer is: no, not always,” says Shawn D’Souza, PhD student at CES and the study’s lead author. “We found strong evidence that lethal humans such as hunters and fishers are indeed perceived as threatening. Animals in areas exposed to lethal humans tend to be more vigilant and spend less time foraging. In contrast, responses to non-lethal humans such as tourists or researchers are weaker and more variable.”

Roads and Settlements Can Feel Safer

One of the more unexpected findings was that human infrastructure, including roads and settlements, sometimes caused animals to become less watchful.

“In certain cases, these areas can function as perceived refuges,” D’Souza explains. “Predators often avoid humans, which can make areas near people feel safer for some prey species.”

Co-author Maria Thaker, Professor at CES, says another factor may be the open vegetation commonly found beside roads. These cleared spaces can provide appealing grazing areas for smaller animals. However, feeding near roads also exposes them to the danger of being struck by vehicles.

The Costs of Staying Alert

The researchers focused on foraging, vigilance, and movement because each behavior reflects the difficult choices animals make when assessing danger.

Every moment spent scanning for threats is time taken away from feeding. Changes in movement can also affect how much energy an animal uses and whether it can reach food, shelter, or other important resources. Because these behaviors influence survival and reproduction, they can reveal how fear of people may shape wildlife populations over time.

Animals Adjust to the Level of Risk

The findings generally support the “risk allocation hypothesis,” which proposes that animals change their behavior according to how severe and predictable a threat appears.

When danger is frequent and intense, animals tend to remain cautious, D’Souza says. When a threat is limited or occurs in a predictable way, wildlife may be more willing to relax and resume normal activities.

These decisions can also have consequences far beyond a single animal. Changes in feeding, movement, and fear can spread through ecosystems, affecting grazing patterns, predator-prey relationships, and broader ecological stability.

Possible Implications for Wildlife Conflict

Co-author Kartik Shanker, Professor at CES, says the behavioral effects of lethal human activity could have implications for managing conflict between people and wildlife. According to Shanker, limited culling may sometimes discourage wild animals from entering human-dominated areas more effectively than several other approaches currently in use.

The researchers say more work is needed to predict how different species will respond in different environments.

“We need more predictive frameworks that link behavioral responses to ecological and evolutionary context. That includes incorporating species traits, past exposure to humans, predator communities, and landscape structure,” says D’Souza.

He adds that long-term and experimental research will be essential for determining whether animals are simply becoming accustomed to human activity or experiencing deeper evolutionary changes.

The discoveries were made by researchers at the University of Warwick and the University of Colorado Boulder. Their findings were published in the Monthly Notices of the Royal Astronomical Society (MNRAS).

White Dwarfs Hidden by Brighter Companions

Each white dwarf orbits alongside a red dwarf star. Because the red dwarfs appear larger and brighter, the systems looked like they contained only a single star when viewed in visible light.

The new observations revealed that all four nearby red dwarfs were concealing white dwarf companions.

First author, Dr. Mairi O’Brien, Research Fellow, University of Warwick said: “Nearby isolated white dwarfs are usually easy to find, but we couldn’t see these four stars directly in visible wavelengths because their red dwarf companions were drowning out their light. It’s a reminder that even in our own cosmic neighborhood, we can still find surprises if we look in the right way, at the right wavelengths.”

Astronomers have spent decades carefully cataloging stars near the Sun, yet white dwarfs in systems like these remain difficult to detect. The four systems attracted attention because their visible stars showed a pronounced radial wobble.

This motion occurs when a star moves slightly toward and away from Earth as an unseen, massive object pulls on it while orbiting. The wobble suggested that each red dwarf had a hidden companion.

Hubble Ultraviolet Data Reveals the Stars

The researchers used ultraviolet spectrograph data from the Hubble Space Telescope to examine the four systems in greater detail.

White dwarfs are generally much easier to recognize in ultraviolet light. Red dwarfs, however, can produce powerful flares that imitate the ultraviolet signal of a white dwarf, making confirmation more difficult.

To separate the true signals from the effects of stellar flaring, the team developed specialized calibration methods. This analysis officially confirmed that all four systems contained white dwarf stars.

A White Dwarf Hidden for 27 Years

One of the systems, G 203-47, was especially puzzling. Although it is located only 25 light-years away, astronomers needed 27 years after first detecting its radial wobble to identify the hidden white dwarf.

The object is now recognized as the ninth closest white dwarf to the Sun.

G 203-47 also behaves differently from similar binary systems. Its red dwarf takes more than 100 days to complete one rotation, even though it circles the white dwarf every 14.9 days.

Under normal circumstances, the gravitational interaction between two closely orbiting stars would be expected to synchronize their motion through tidal locking. The Moon and Earth provide a familiar example, since the same side of the Moon continually faces Earth.

In G 203-47, however, the red dwarf rotates far too slowly to be synchronized with its orbit.

Coauthor Dr. David Wilson, Research Associate, University of Colorado Boulder, said: “What’s fascinating is that G 203-47 shouldn’t be rotating this slowly if it formed the same way as similar systems. This suggests that these binaries have had very different evolutionary histories. Some underwent violent, prolonged interactions early on that locked them tidally. Others, like G 203-47, experienced gentler, briefer encounters that left them in this unusual state.”

Clues About Binary Star Evolution

The unusual rotation of G 203-47 suggests that not all white dwarf and red dwarf pairs developed through the same process.

Some systems may have experienced long and intense interactions early in their histories, causing the stars to become tidally locked. Others may have interacted for a shorter period and with less force, leaving their rotations unsynchronized.

The four discoveries have also allowed astronomers to revise the census of white dwarfs within 20 parsecs (65 light-years).

Previous population models predicted that roughly 4 to 5 closely orbiting white dwarf and red dwarf systems should exist in this region. The researchers identified exactly four, closely matching those theoretical estimates.

More Hidden White Dwarfs May Be Nearby

The discoveries may not complete the picture. Most nearby red dwarfs have not yet been systematically examined for concealed white dwarf companions.

Professor Pier-Emmanuel Tremblay, Astronomy and Astrophysics Group, University of Warwick, said: “Only about 30 percent of red dwarfs within 20 parsecs have been systematically surveyed for hidden white dwarf companions. We think there could be as many as 9 or 10 additional binary systems in our local stellar environment that we haven’t found yet. If we put more targeted effort into observing red dwarfs, perhaps we will find more surprises like this.”

The findings, published in the Journal of Epidemiology and Community Health, add to growing evidence that staying socially and culturally active could play an important role in healthy aging.

Cultural Activities and Biological Aging

Everyone grows older, but the rate at which the body ages can vary from person to person. Physiological age reflects how well the body is functioning and may differ from chronological age, which is simply the number of years someone has lived.

Previous research has linked cultural activities, such as going to the movies, museums, and live performances, with better health and well-being in older adults. However, relatively few studies have explored whether these activities are connected to physiological aging itself.

Researchers at the Institute of Science Tokyo in Japan say they have carried out the first longitudinal study to examine this relationship while accounting for unmeasured factors that remain stable over time.

How the Study Measured Aging

The team analyzed data from 1,899 adults participating in the English Longitudinal Study of Ageing, an ongoing population-based study of a nationally representative sample of adults aged 50 and older living in England.

Participants contributed data during at least two survey waves conducted in 2004/2005, 2006/2007, or 2008/2009.

To estimate physiological age, nurses measured 10 indicators of physical health, including pulse pressure, diastolic blood pressure, forced expiratory volume, hemoglobin concentration, fibrinogen, glycated hemoglobin, low-density lipoprotein (LDL) cholesterol, body mass index (BMI), grip strength, and walking speed. These measurements were combined into a single physiological age score.

Participants also reported how often they attended (a) the cinema, (b) a museum or art gallery, and (c) a theater, concert, or the opera. Each activity was scored on a scale from 0 (never) to 5 (twice a month or more), producing a total cultural engagement score ranging from 0 to 15.

Higher Cultural Engagement Linked to Younger Bodies

People with higher levels of cultural engagement, defined as taking part in cultural activities at least every few months, had an average physiological age of 66.9 years. In comparison, those with lower levels of participation had an average physiological age of 69.9 years, a difference of about three years.

Participants with higher cultural engagement were also more likely to be women, have higher socioeconomic status, be employed, and already enjoy better overall health.

After adjusting for factors such as household income, employment, and chronic health conditions, the researchers found that each one-point increase in cultural engagement score was associated with a 0.085-year (31-day) reduction in physiological age.

Why Cultural Activities Might Matter

The researchers suggest several possible explanations for the association. Cultural activities can strengthen social connections, encourage healthier lifestyle habits, and support better mental health, all of which may contribute to slower physiological aging.

Because the research was observational, it cannot determine whether cultural activities directly slow aging. The authors also note that reverse causation is possible, meaning healthier people may simply be more able to attend cultural events.

Even so, they argue that cultural engagement is a modifiable behavior that could become an effective public health strategy. “Notably, the impact can be comparable to frequent physical activity,” they write.

The researchers also say that making cultural events more geographically and financially accessible could allow more people to participate.

Additional research will be needed to determine whether encouraging greater cultural engagement leads to lasting improvements in health and healthier aging over the long term.