Climate change could mean more bugs and bad things for the world's crops
More bugs, more problems.
A new study published in the journal Science suggests that as the world warms due to human-caused climate change, more and more bugs will populate the globe.
And while that seems like nothing more than a disgusting inconvenience, a world with more bugs could mean bad things for human food supplies around the world.
A team of scientists led by Curtis Deutsche and Joshua Tewskbury examined how insects would affect three of the most important crops: rice, maize, and wheat.
They found that any increase in global temperature could lead to insect-driven losses of 10 to 25 percent, especially in places used to more moderate temperatures. A 2 degree Celsius rise in temperature could lead to 213 million ton loss in the three crops measured.
“When the temperature increases, the insects' metabolism increases so they have to eat more,” co-author Steve Merrill said in a statement. The relationship between insect metabolism and crop loss is direct and “robust across all species,” Deutsche said in an email. That’s why they were able to see such a strong correlation.
However, from region to region, the way that heat will affect crops and insects will vary. For example, wheat grows best in cooler temperatures, so if the temperature rises, the wheat will face both a less favorable climate for growth and a higher insect population.
The impact on maize, however, will depend since the crop does well in different environments.
In more tropical climates, insects are already in their best environment for growth, so a rise in temperature would actually slow their metabolism down causing them to eat less, Merril explained. The same goes for rice as well since it’s grown in a tropical climate.
If you follow this scenario to its logical conclusion, the world's crops could be in serious trouble.
The article estimates that rice, maize, and wheat account for 42 percent of the calories consumed by people worldwide. And if there is a shortage of something that feeds a good portion of the world, that’s when conflict and starvation become a concern, especially in countries that already have high levels of food insecurity.
“Countries with high losses to insects already are likely to feel the pinch more strongly,” Deutsche explained. A 50 percent increase in pest consumption is going to be a much bigger deal to country that’s already losing 20 percent of their crop to pests, versus a country only losing 5 percent.
“This unfortunately has a strong overlap with the same countries that have high food insecurity, like African nations,” he said.
There are ways around it, but that requires money.
Rich countries will be able to engineer more pesticides or pest-resistant crops. So even though the U.S., France, and China are likely to be “hit the hardest” according to Merrill's estimations, those are the countries that are most able to afford conducting the necessary research.
Rob Dunn, an ecologist unaffiliated with the study, said the real long-term solution is biodiversity -- meaning we need to expand the number of crops we rely on. Humanity can no longer subsist on a few crops to feed billions, especially in the age of global warming.
“What we need [to achieve biodiversity] is a global commitment to managing the sustainability and resilience of our crops and the species associated with them (the hundreds of thousands of species) as grand and ambitious as our efforts to destroy each other with the tools of war,” Dunn said in an email.
Any research done in the field of biodiversity is from donations.
“It isn’t sexy. It isn't attractive to funders. And yet, better to be boring and fed, than hungry any day,” Dunn said.
The issue is what to do next.
“Our choice now is not whether or not we will allow warming to occur, but how much warming we're willing to tolerate,” Deutsche said in a statement.
