Climate change damaging male fertility

Published by  News Archive

On 13th Nov 2018

Climate change could pose a threat to male fertility – according to new research from the University of East Anglia.

New findings published today in the journal Nature Communications reveal that heatwaves damage sperm in insects – with negative impacts for fertility across generations.

The research team say that male infertility during heatwaves could help to explain why climate change is having such an impact on species populations, including climate-related extinctions in recent years.

Research group leader Prof Matt Gage, from UEA’s School of Biological Sciences, said: “We know that biodiversity is suffering under climate change, but the specific causes and sensitivities are hard to pin down.

“We’ve shown in this work that sperm function is an especially sensitive trait when the environment heats up, and in a model system representing a huge amount of global biodiversity.

“Since sperm function is essential for reproduction and population viability, these findings could provide one explanation for why biodiversity is suffering under climate change.

“A warmer atmosphere will be more volatile and hazardous, with extreme events like heatwaves becoming increasingly frequent, intense and widespread.

“Heatwaves are particularly damaging extreme weather events. Local extinctions are known to occur when temperature changes become too intense. We wanted to know why this happens. And one answer could be related to sperm.”

The research team investigated the red flour beetle (Tribolium castaneum) to explore the effects of simulated heatwaves on male reproduction.

The beetles were exposed to either standard control conditions or five-day heatwave temperatures, which were 5°C to 7°C above their thermal optimum.

Afterwards, a variety of experiments assessed the potential damage to reproductive success, sperm function and offspring quality.

Heatwaves killed sperm

The team found that heatwaves halved the amount of offspring males could produce, and a second heatwave almost sterilised males.

Females, by contrast, were unaffected by heatwave conditions. However, female reproduction was affected indirectly because experiments showed that heatwaves damaged inseminated sperm within female reproductive tracts.

Following experimental heatwaves, males reduced sperm production by three-quarters, and any sperm produced then struggled to migrate into the female tract and were more likely to die before fertilisation.

Kris Sales, a postgraduate researcher who led the research, said: “Our research shows that heatwaves halve male reproductive fitness, and it was surprising how consistent the effect was.”

The group also explored the underlying causes of male vulnerability. Heatwaves caused some impact on male sexual behaviour – with males mating half as frequently as controls.

Heatwaves caused damage across generations

“Two concerning results were the impact of successive heatwaves on males, and the impacts of heatwaves on future generations,” said Sales.

“When males were exposed to two heatwave events 10 days apart, their offspring production was less than 1 per cent of the control group. Insects in nature are likely to experience multiple heatwave events, which could become a problem for population productivity if male reproduction cannot adapt or recover.”

The research also shows that offspring sired by heatwaved dads – or their sperm - live shorter lives – by a couple of months.

And the reproductive performance of sons produced by dads – or sperm – exposed to heatwave conditions was also impacted. Sons were found to be less able to fertilise a series of potential mates, and produced less offspring.

The researchers warn that this could add extra pressure to populations already suffering through climate change over time.

“Beetles are thought to constitute a quarter of biodiversity, so these results are very important for understanding how species react to climate change. Research has also shown that heat shock can damage male reproduction in warm blooded animals too, and past work has shown that this leads to infertility in mammals,” added Sales.

The researchers hope that the effects can be incorporated into models predicting species vulnerability, and ultimately help inform societal understanding and conservation actions.

The work was funded by Natural Environment Research Council (NERC) and the EnvEast DTP, UEA, and the Leverhulme Trust.

‘Experimental heatwaves compromise sperm function and cause transgererational damage in a model insect’ is published in Nature Communications on Tuesday, November 12, 2018.

Latest News

  News
Children and adults at ribbon cutting at IntoUniversity and UEA education centre opening event
17 Sep 2021

Thousands of local young people set to benefit as new education centre officially opens its doors

A new education centre was officially opened in West Earlham, one which is set to benefit thousands of young people from the most disadvantaged backgrounds in...

Read more >
  News
DNA
16 Sep 2021

Times Higher Education table puts UEA in the world’s top 100 for Life Sciences

The University of East Anglia (UEA) has maintained its place as a world top 100 university for Life Sciences degrees in the 2022 Times Higher Education (THE)...

Read more >
  News
16 Sep 2021

Vattenfall partnership to unlock benefits of offshore wind to the region

The University of East Anglia (UEA) and Vattenfall have announced a partnership that will place the East of England at the forefront of the offshore wind...

Read more >
  News
16 Sep 2021

How climate change could impact algae in the global ocean

Global warming is likely to cause abrupt changes to important algal communities because of shifting biodiversity ‘break point’ boundaries in the oceans –...

Read more >
Are you searching for something?
  News
16 Sep 2021

How climate change could impact algae in the global ocean

Global warming is likely to cause abrupt changes to important algal communities because of shifting biodiversity ‘break point’ boundaries in the oceans –...

Read more >
  News
15 Sep 2021

UEA breakthrough could protect against breast cancer progression

Leading scientists have identified a possible link between antibiotic use and the speed of breast cancer growth in mice, and identified a type of immune cell...

Read more >
  News
15 Sep 2021

Ambitious research to study fundamental earth and environmental science questions

The University of East Anglia is leading one of five innovative new research projects that could push the boundaries of science and help us understand key...

Read more >
  News
08 Sep 2021

£1.4 million UEA project to improve flu jab uptake in care home staff

Researchers at the University of East Anglia are launching a project to increase the number of care home staff that take up the flu vaccine.

Read more >
  News
02 Sep 2021

Indigenous and local communities key to successful nature conservation

Indigenous Peoples and local communities provide the best long-term outcomes for conservation, according to new research from UEA's School of International...

Read more >
  News
Globe on a book
02 Sep 2021

Success in Times Higher Education rankings sees UEA rise to five-year high

The reach of University of East Anglia’s (UEA’s) research around the world was ranked in the global top 50, as part of an international rankings table that saw...

Read more >
  News
24 Aug 2021

UEA part of international team measuring how the Arctic responds to climate change

Researchers at the University of East Anglia have helped develop a new way to measure how Arctic plants respond to climate change.

Read more >