In a study of burying beetles, researchers from the Biodiversity Research Center, Academia Sinica, and collaborating institutions recently found that cooperative groups have similarly high breeding success at all temperatures and elevations, whereas non-cooperative groups had higher breeding success only at intermediate temperatures and elevations. In the face of climate change, studies predicting how animal societies and humans adapt to changes in climate have become a priority. The research led by Assistant Research Fellow Sheng-Feng Shen, was published in the life science journal eLife on May 13.

         The ability to form cooperative societies is one explanation of why humans and social insects have come to dominate the earth. The ability to live and work together in groups likely helped the earliest humans to leave their savannah homes in Africa and successfully settle around the globe. In doing so, humans shifted from being savannah specialists to generalists able to cope with a range of different environments. Cooperation is also believed to be a key to the global success of social insects like bees and ants. However, testing the idea that cooperation allows animals to become generalists that thrive in diverse environments—an idea referred to as the ‘social conquest hypothesis’—is difficult.

         Climate change has added a new sense of urgency to understanding how species adapt to changing environments, and some studies of humans and other animals have suggested that cooperation may increase or decrease in changing environments. Living in social groups has both benefits and drawbacks: it helps some animals to avoid being eaten by predators, but it also creates more competition for mates, food or other resources. As such, predicting how climate change will impact human and animal societies has also been difficult to test.

         Recently, a research team from the Biodiversity Research Center examined the ecological consequences of social cooperation by quantifying the fitness of cooperative (large groups) and non-cooperative (small groups) of burying beetles (Nicrophorus nepalensis) at different elevations and different temperatures. Burying beetles find dead animals and then bury them to be eaten by their larvae. They often fight each other to ensure that their own young get exclusive access to a food source. However, working together allows the beetles to bury animal carcasses before flies and other competitors discover it. The researchers compared how much the beetles cooperated at different elevations in the mountains of Taiwan. At each elevation the beetles faced different challenges: higher elevations were colder but had fewer flies, while lower elevations were warmer but had more flies. They showed that cooperative groups performed as thermal generalists with similarly high breeding success at all temperatures and elevations, whereas non-cooperative groups performed as thermal specialists with higher breeding success only at intermediate temperatures and elevations.

         Since many studies have suggested that global warming might cause higher levels of conflict in human societies, by studying how changes in an environment impact on cooperation in burying beetles, the researchers provide new insights into how climate change may affect the future success of other social animals, including humans.

         The complete list of authors is: Syuan-Jyun Sun, Dustin Reid Rubenstein, Bo-Fei Chen, Shih-Fan Chan, Jian-Nan Liu, Mark Liu, Wenbe Hwang, Ping-Shih Yang, Sheng-Feng Shen. In addition to Academia Sinica Biodiversity Research Center, authors came from the Department of Entomology, National Taiwan University; the Department of Ecology, Evolution and Environmental Biology, Columbia University, and the Department of Ecoscience and Ecotechnology, National University of Tainan.

         The full article entitled “Climate-mediated cooperation promotes niche expansion in burying beetles” can be found at the eLife website at: http://elifesciences.org/content/3/e02440