Why some birds fear new things while others adapt easily

Walk into a park and toss a piece of bread. A pigeon rushes in, but a heron watches from afar. One sees food; the other sees a possible trap.

That difference – between boldness and hesitation – is called neophobia, the fear of novelty. It can decide how a species survives in an unpredictable world.

Scientists have now completed the biggest study to date on neophobia. The research covered 136 bird species across six continents.

The work was led by Dr. Rachael Miller from Anglia Ruskin University and the University of Cambridge, with collaborators from the ManyBirds Project.

The goal was simple: find out why some birds fear new things more than others.

How birds show fear

The researchers offered each bird a familiar treat – once alone and once beside a strange object. The setup looked harmless – brightly colored toys, soft materials, and nothing resembling predators.

Yet reactions varied widely. Some birds approached right away. Others froze. The delay in touching the food measured how much fear novelty caused.

Flamingos and grebes hesitated the most. Falcons and pheasants barely cared. Across all 1,439 birds, patterns started to form.

Diet and migration stood out as the strongest predictors of fear. Specialists that eat only a few types of food showed higher neophobia.

Generalists, used to variety, were bolder. Migratory species, which face new environments often, also showed stronger fear – perhaps an evolutionary defense against unseen dangers.

Fear patterns stay stable

Neophobia turned out to be more than a passing mood. A bird that hesitated once usually hesitated again weeks later. The behavior stayed stable, showing a personality-like consistency.

“Neophobia comes with benefits and costs. Neophobic responses can protect an individual from potential risks, but may also decrease opportunities to exploit novel resources, such as unknown food or nesting sites,” explained study lead author Dr. Rachael Miller.

That trade-off matters. Species that stay wary might avoid poison or traps but fail to adapt to human-dominated environments.

Birds that dare to explore new foods or nesting places might gain an edge in cities and farmlands. In a changing climate, adaptability could mean survival.

Birds share fear cues

Fear spread easily in company. Birds tested together waited longer to approach food than those tested alone. Social cues seemed to matter.

One nervous individual could make the rest cautious. Researchers had expected the opposite – that being in a group would reduce fear by sharing the risk. The results flipped that idea. Sometimes watching others hesitate only reinforces worry.

This kind of social ripple shows that fear isn’t just an instinct but also a communication loop. A single slow reaction can shape group behavior.

Territory, habitat, and domestication

Birds that defended territories all year were more cautious than those that did so seasonally. Territorial living may breed caution. A fixed space means higher stakes – one bad choice could ruin safety.

Habitat also mattered. Species from simple, open landscapes were slower to approach novelty than those from dense, complex habitats. Forest birds seemed more curious.

Complexity may train exploration. Domesticated birds showed the least fear, which made sense; their lives revolve around predictable food and care.

Ecological drivers of fear

Two big ideas explain these patterns. The Neophobia Threshold Hypothesis suggests that caution evolves in specialists who rely on stable conditions.

The Dangerous Niche Hypothesis proposes that animals in unpredictable or risky habitats – like migratory species – evolve stronger avoidance to survive. The study found support for both. Together, they describe how fear can evolve differently depending on how species live.

The results also hint that fear might limit evolution itself. High neophobia could prevent birds from experimenting with new foods or habitats, narrowing their chances to adapt. Over time, that could lock species into fragile niches.

What birds’ fear means

Dr. Miller sees this research as a starting point. “Neophobia plays an important role in assessing how species might respond to change.

“Species that are more wary of unfamiliar objects or situations may struggle to adapt to factors such as climate change or urbanisation, while those with lower neophobia may be more flexible or resilient.”

According to Dr. Miller, the study also highlights the power of big team science. “Through the ManyBirds Project, we were able to pool data and expertise from across the globe, helping us to uncover the hidden rules shaping animal behavior on an evolutionary scale.”

Broader implications of the research

Dr. Megan Lambert from the University of Veterinary Medicine in Vienna said the findings have important implications, particularly for species experiencing habitat change or being reintroduced into the wild from captive breeding programs.

“By better understanding these behavioral tendencies, conservationists can tailor strategies to improve the chances of survival in at-risk species,” noted Dr. Lambert.

The ManyBirds study shows that fear itself evolves with purpose. It keeps species alive but can hold them back too.

A flamingo’s hesitation and a falcon’s boldness tell two sides of the same story – one about risk, safety, and the fine balance between caution and curiosity that drives life forward.

The study is published in the journal PLOS Biology.

—–

Like what you read? Subscribe to our newsletter for engaging articles, exclusive content, and the latest updates. 

Check us out on EarthSnap, a free app brought to you by Eric Ralls and Earth.com.

—–