According to the University of Liverpool, UK, global climate change could make some species sterile and see them succumb earlier than expected.
Published in Trends in Ecology and Evolution, researchers have analysed extensive data from a wide variety of plants and animals and are suggesting that organisms lose fertility at lower temperatures than their critical thermal limit (CTL). Could there be a way of battling global climate change to reduce its effect on animal health?
Understanding global climate change
Currently, biologists and conservationists are attempting to predict where species will be lost due to climate change, so they can build suitable reserves in the locations they will eventually need to move to.
However, most of the data regarding when temperature will prevent species surviving in an area is based on the ‘critical thermal limit’ or CTL – the temperature at which they collapse, stop moving or die.
Dr Tom Price from the University’s Institute of Integrative Biology explains: “There is a risk that we are underestimating the impact of climate change on species survival because we have focused on the temperatures that are lethal to organisms, rather than the temperatures at which organisms can no longer breed.”
Vulnerable species
Certain groups of species are thought to be most vulnerable to climate-induced fertility loss, such as cold-blooded animals and aquatic species.
“Currently the information we have suggests this will be a serious issue for many organisms. But which ones are most at risk? Are fertility losses going to be enough to wipe out populations, or can just a few fertile individuals keep populations going? At the moment, we just don’t know. We need more data.” adds Price.
The Thermal Fertility Limit (TFL), is a proposed measure the researchers have introduced to look at how organisms’ function at extreme temperatures, focusing on fertility.
Time to take action
Price explains further: “We think that if biologists’ study TFLs as well as CTLs then we will be able to work out whether fertility losses due to climate change are something to worry about, which organisms are particularly vulnerable to these thermal fertility losses, and how to design conservation programmes that will allow species to survive our changing climate.
“We need researchers across the world, working in very different systems, from fish, to coral, to flowers, to mammals and flies, to find a way to measure how temperature impacts fertility in that organism and compare it to estimates of the temperature at which they die or stop functioning,” urges Dr Price.
