Insects can't adapt to drastic temperature changes, may be wiped out by climate change: Study

Many insects may have to migrate to places with temperatures that suit them, or change their behaviours. PHOTO: SAM ENGLAND
Insects are physiologically unable to tolerate wider temperatures. PHOTO: SAM ENGLAND

SINGAPORE - Insects may have to become "climate refugees", migrating to other parts of the world, or perish with climate change, suggests a new study.

The six-legged critters are found to be able to adapt to only marginal temperature changes. This means any drastic heating or cooling of the earth brought on by climate change would likely spell doom for them.

In a study of more than 100 species of insects, an international team led by researchers at the University of Bristol found that for every 1 deg C shift in the environment's temperature, insects could internally adjust their survival temperature range by only 0.092 deg C when temperatures rise, and 0.147 deg C when the environment cools.

Ms Hester Weaving, a PhD student at the university's School of Biological Sciences and lead author of the study, said this means insects are physiologically unable to tolerate wider temperatures.

As a result, many insects may have to migrate to places with temperatures that suit them or change their behaviours, such as being more active at night if it gets too hot in the day.

Ms Weaving said: "Our comparative study identified some major gaps in understanding insect responses to climate change, and we urge more studies to be done on species in under-represented groups and locations."

Besides this, the study published in scientific journal Nature this month also reported that juvenile insects have a greater ability to acclimatise to temperatures.

This suggests that there may be critical periods of life when insects can better compensate for changes in temperatures, which may improve their climate resilience later in life.

The study said: "Insects fulfil diverse ecological roles as pollinators, agricultural pests and disease vectors, and there is global concern over recent, rapid declines in abundance of rare, ecologically or agriculturally important species and, conversely, spikes in pest outbreaks."

It added that how insects respond to climate change via their adaptability to temperatures remains an important topic of debate.

As a continuation of their research, the team is currently investigating how the reproduction of insects is affected by exposure to extreme temperatures.

This may be important in predicting future distributions of insects.

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