Global climate change is one of the most alarming environmental issues right now, unless you're a parasite. A new study suggests that a species of parasitic worms is using the rising temperatures to increase its chances of survival at the cost of the fish populations it uses as hosts.Parasitic tapeworms found in sticklebacks – small fish commonly found in the waters of Europe, North America and Japan – are providing scientists with a model to study the effects of global warming on the balance between parasites and their hosts. Scientists believe that warmer temperatures could create a shift in favor of the parasites, which could increase the rate and number of parasite infections in fish and other animals that eat them.Researchers from the University of Leicester recently published a study that looked at the relationship between sticklebacks and parasitic tapeworms. Two groups of infected sticklebacks were kept in separate tanks for eight weeks at two temperatures: 59 and 68 degrees Fahrenheit. The researchers found that the fish kept at 68 degrees Fahrenheit had worms that grew up to four times faster, and were on average, four times heavier than the ones kept in the cooler water.