The Times Australia
The Times World News

.

scientists discover a new way climate change threatens cold-blooded animals

  • Written by Lesley Alton, Research Fellow, Monash University
scientists discover a new way climate change threatens cold-blooded animals

All animals need energy to live. They use it to breathe, circulate blood, digest food and move. Young animals use energy to grow, and later in life[1], to reproduce.

Increased body temperature increases the rate at which an animal uses energy. Because cold-blooded animals rely on the thermal conditions of their environment to regulate their body temperature, they’re expected to need more energy as the planet warms.

However, our new research, published today in Nature Climate Change[2], suggests temperature is not the only environmental factor affecting the future energy needs of cold-blooded animals. How they interact with other species will also play a role.

Our findings suggest cold-blooded animals will need even more energy in a warmer world than previously thought. This may increase their extinction risk.

baby turtle emerging from shell
Young animals use energy to grow, and later in life, to reproduce. Shutterstock

What we already know

The amount of energy animals use in a given amount of time is called their metabolic rate.

Metabolic rate is influenced by a variety of factors, including body size and activity levels. Larger animals[3] have higher metabolic rates than smaller animals, and active animals have higher metabolic rates than inactive animals.

Metabolic rate also depends on body temperature. This is because temperature affects the rate at which the biochemical reactions involved in energy metabolism proceed. Generally, if an animal’s body temperature increases, its metabolic rate will accelerate exponentially[4].

Most animals alive today are cold-blooded, or “ectotherms”. Insects, worms, fish, crustaceans, amphibians and reptiles – basically all creatures[5] except mammals and birds – are ectotherms.

As human-induced climate change raises global temperatures, the body temperatures of cold-blooded animals are also expected to rise.

Researchers say[6] the metabolic rate of some land-based ectotherms may have already increased by between 3.5% and 12% due to climate warming that’s already occurred. But this prediction doesn’t account for the animals’ capacity to physiologically “acclimate” to warmer temperatures.

Acclimation refers to an animal’s ability to remodel its physiology to cope with a change in its environment.

But rarely can acclimation fully negate the effect of temperature on metabolic processes. For this reason, by the end of the century land-based ectotherms are still predicted to have metabolic rates about 20% to 30%[7] higher than they are now.

Having a higher metabolic rate means that animals will need more food. This means they might starve if more food is not available, and leaves them less energy to find a mate and reproduce.

Read more: Why are bigger animals more energy-efficient? A new answer to a centuries-old biological puzzle[8]

crocodile carrying baby in its mouth
As climate change raises global temperatures, the body temperatures of cold-blooded animals are also expected to rise. Shutterstock

Our research

Previous research attempts to understand the energetic costs of climate warming for ectotherms were limited in one important respect. They predominantly used animals studied in relatively simple laboratory environments where the only challenge they faced was a change in temperature.

However, animals face many other challenges in nature. This includes interacting with other species, such as competing for food and predator-prey relationships.

Even though species interact all the time in nature, we rarely study[9] how this affects metabolic rates.

We wanted to examine how species interactions might alter predictions about the energetic costs of climate warming for cold-blooded animals. To do this, we turned to the fruit fly (from the genus Drosophila).

Fruit fly species lay their eggs[10] in rotting plant material. The larvae that hatch from these eggs interact[11] and compete for food.

Our study involved rearing fruit fly species alone or together at different temperatures. We found when two species of fruit fly larvae compete for food at warmer temperatures, they were more active as adults than adults that didn’t compete with other species as larvae. This means they also used more energy.

From this, we used modelling to deduce that species interactions at warmer global temperatures increase the future energy needs of fruit flies by between 3% and 16%.

These findings suggest previous studies have underestimated the energetic cost of climate warming for ectotherms. That means purely physiological approaches to understanding the consequences of climate change for cold-blooded animals are likely to be insufficient.

Read more: Young cold-blooded animals are suffering the most as Earth heats up, research finds[12]

close up image of fruit fly
Previous studies have underestimated the energetic cost of climate warming for ectotherms. Shutterstock

Let’s get real

Understanding the energy needs of animals is important for understanding how they’ll survive, reproduce and evolve[13] in challenging environments.

In a warmer world, hotter ectotherms will need more energy to survive and reproduce. If there is not enough food to meet their bodies’ energy demands, their extinction risk may increase[14].

Clearly, we must more accurately predict how climate warming will threaten biodiversity. This means studying the responses of animals to temperature change under more realistic conditions.

Read more: Move over, honeybees: Aussie native bees steal the show with unique social and foraging behaviours[15]

References

  1. ^ later in life (www.science.org)
  2. ^ Nature Climate Change (www.nature.com)
  3. ^ Larger animals (theconversation.com)
  4. ^ accelerate exponentially (www.science.org)
  5. ^ all creatures (tpwd.texas.gov)
  6. ^ Researchers say (www.nature.com)
  7. ^ 20% to 30% (www.nature.com)
  8. ^ Why are bigger animals more energy-efficient? A new answer to a centuries-old biological puzzle (theconversation.com)
  9. ^ rarely study (onlinelibrary.wiley.com)
  10. ^ lay their eggs (www.journals.uchicago.edu)
  11. ^ interact (www.jstor.org)
  12. ^ Young cold-blooded animals are suffering the most as Earth heats up, research finds (theconversation.com)
  13. ^ evolve (www.science.org)
  14. ^ may increase (www.jstor.org)
  15. ^ Move over, honeybees: Aussie native bees steal the show with unique social and foraging behaviours (theconversation.com)

Read more https://theconversation.com/lets-get-real-scientists-discover-a-new-way-climate-change-threatens-cold-blooded-animals-201076

Times Magazine

Headless CMS in Digital Twins and 3D Product Experiences

Image by freepik As the metaverse becomes more advanced and accessible, it's clear that multiple sectors will use digital twins and 3D product experiences to visualize, connect, and streamline efforts better. A digital twin is a virtual replica of ...

The Decline of Hyper-Casual: How Mid-Core Mobile Games Took Over in 2025

In recent years, the mobile gaming landscape has undergone a significant transformation, with mid-core mobile games emerging as the dominant force in app stores by 2025. This shift is underpinned by changing user habits and evolving monetization tr...

Understanding ITIL 4 and PRINCE2 Project Management Synergy

Key Highlights ITIL 4 focuses on IT service management, emphasising continual improvement and value creation through modern digital transformation approaches. PRINCE2 project management supports systematic planning and execution of projects wit...

What AI Adoption Means for the Future of Workplace Risk Management

Image by freepik As industrial operations become more complex and fast-paced, the risks faced by workers and employers alike continue to grow. Traditional safety models—reliant on manual oversight, reactive investigations, and standardised checklist...

From Beach Bops to Alpine Anthems: Your Sonos Survival Guide for a Long Weekend Escape

Alright, fellow adventurers and relaxation enthusiasts! So, you've packed your bags, charged your devices, and mentally prepared for that glorious King's Birthday long weekend. But hold on, are you really ready? Because a true long weekend warrior kn...

Effective Commercial Pest Control Solutions for a Safer Workplace

Keeping a workplace clean, safe, and free from pests is essential for maintaining productivity, protecting employee health, and upholding a company's reputation. Pests pose health risks, can cause structural damage, and can lead to serious legal an...

The Times Features

Exploring the Curriculum at a Modern Junior School in Melbourne

Key Highlights The curriculum at junior schools emphasises whole-person development, catering to children’s physical, emotional, and intellectual needs. It ensures early year...

Distressed by all the bad news? Here’s how to stay informed but still look after yourself

If you’re feeling like the news is particularly bad at the moment, you’re not alone. But many of us can’t look away – and don’t want to. Engaging with news can help us make ...

The Role of Your GP in Creating a Chronic Disease Management Plan That Works

Living with a long-term condition, whether that is diabetes, asthma, arthritis or heart disease, means making hundreds of small decisions every day. You plan your diet against m...

Troubleshooting Flickering Lights: A Comprehensive Guide for Homeowners

Image by rawpixel.com on Freepik Effectively addressing flickering lights in your home is more than just a matter of convenience; it's a pivotal aspect of both home safety and en...

My shins hurt after running. Could it be shin splints?

If you’ve started running for the first time, started again after a break, or your workout is more intense, you might have felt it. A dull, nagging ache down your shins after...

Metal Roof Replacement Cost Per Square Metre in 2025: A Comprehensive Guide for Australian Homeowners

In recent years, the trend of installing metal roofs has surged across Australia. With their reputation for being both robust and visually appealing, it's easy to understand thei...