How Heat Waves Impair Animal Cognition and Behavior

Rising global temperatures are doing more than altering landscapes; they are muddled the minds of animals across the globe. From the deserts of South Africa to the mountains of Italy, research indicates that heat waves can significantly impair cognitive function, memory, and emotional regulation in various species.

Cognitive Decline and Learning Hurdles

In South Africa, female southern pied babblers struggle to solve simple problems during extreme heat. While these birds easily navigate around plastic barriers on cool days, they stubbornly peck at the obstacles when temperatures rise.

Similar impairments have been observed in zebra finches in Australia. When attempting to retrieve mealworms from see-through tubes, the birds often simply peck at the tube itself, a behavior described by evolutionary biologist Elizabeth Derryberry as the bird equivalent of “banging your head against a brick wall.”

The impact extends to smaller creatures as well. Mice have shown difficulty navigating mazes and forgetting objects they encountered the previous day when exposed to heat. Male guppies also struggle with maze navigation after spending several days in 90-degree water.

Did You Know? In the 1800s, Belgian astronomer Adolphe Quetelet observed that violent crime in France peaked during the summer months.

The Link Between Heat and Aggression

Heat does not just cloud judgment; it often fuels aggression. A 2023 study of nearly 70,000 dog bite reports across eight US cities, including Chicago and Baltimore, found a 10% higher risk of bites on 90-degree days compared to 60-degree days.

Neuroscientist Clas Linnman suggests that both humans and dogs likely become more stressed and irate as temperatures climb. This trend is mirrored in other species, with a 2025 study from China indicating that cats and snakes are more inclined to bite people in the heat.

In the Italian Apennine Mountains, goat-like chamois become increasingly territorial and aggressive over food as temperatures rise from 54 to 64 degrees Fahrenheit. Similarly, the golden julie fish becomes more confrontational and aggressive when water temperatures rise from 78 to 84 degrees.

Expert Insight: Samantha Carter notes that the stakes here extend beyond individual animal behavior. When cognitive impairments affect critical survival skills—such as a pollinator’s ability to find flowers or a prey animal’s vigilance against predators—the resulting ripple effect could destabilize entire ecosystems.

Biological Impact and Human Health

For animals that cannot regulate their own body temperature, such as insects and fish, the effects are direct. Neuroscientist Emily Baird explains that changes in air temperature affect brain temperature, which may hinder nerve functioning and impact sensing, memory, and learning.

Glass Animals – Heat Waves (Official Video)

In mice, poor performance in hot mazes has been linked to inflammation in the hippocampus, the brain’s memory center, which can lead to the death of neurons. Bumblebees also show a marked decline in learning; fewer than half could associate colours with tastes at 90 degrees, compared to most succeeding at 77 degrees.

Humans are not immune to these effects. Research has linked high temperatures to increased gun violence, gambling, and mental-health-related hospital admissions. A study found that in schools without air conditioning, a school year just one degree Fahrenheit hotter reduces test scores by 1 percent.

Future Implications for Ecosystems

As climate change makes heat waves more frequent, these cognitive impairments could place fragile species at greater risk. If bumblebees forget how to pollinate crops like blueberries and tomatoes, human agriculture may suffer.

Vigilance also declines in extreme heat. In the Kalahari Desert, pied babblers at 96 degrees Fahrenheit failed to distinguish between a wooden box and a taxidermied genet predator, which could lead to higher rates of fatal attacks.

Because temperatures in the Kalahari are rising twice as fast as the global average, and urban areas often experience higher heat, the impact on animal minds may be underestimated. Behavioral adaptation could become the most vital tool for survival on a warming planet.

Frequently Asked Questions

How does heat affect the learning abilities of bumblebees?
Research shows that while most bumblebees can learn to associate specific colours with sweet or bitter tastes at 77 degrees, fewer than half can do so when the temperature reaches 90 degrees.

What is the relationship between heat and dog aggression?
A study across eight US cities found that dog bites were more likely on hot, sunny, and smoggy days, with the risk being 10 percent higher on a 90-degree day than on a 60-degree day.

What happens to a mouse’s brain during extreme heat?
Experiments indicate that heat-induced poor performance in mazes is linked to inflammation in the hippocampus, the brain’s memory center, and can result in the death of neurons.

How do you think rising temperatures might change the way we interact with the animals in our own communities?