Researchers at the University of Southampton have forecast a global shift towards smaller birds and mammals over the next century.
According to the research team, small, fast-lived, highly fertile, and insect-eating animals, which can thrive in all sorts of habitats, will predominate in the future. Rodents and songbirds are examples of the so-called ‘winners.’ Less adaptable, slow-lived species, requiring specialist habitats, will be more likely to face extinction. Among the so-called ‘losers’ are the black rhino and the tawny eagle.
The researchers focused on more than 15,000 living mammals and birds and considered the following five characteristics: body mass, breadth of habitat, diet, litter or clutch size, and length of time between generations. Using this data and data from the IUCN’s Red List of Threatened Species, the researchers used modern statistical tools to project and evaluate the loss of biodiversity.
The study, which was recently published in the journal Nature Communications, predicts that the average body mass of mammals will collectively decline by 25% over just the next 100 years. Over the past 130,000 years, the average body size of mammals only declined 14%.
This substantial downsizing of animals is forecasted to occur due to the effects of ecological change. But, according to the study’s lead author, the loss of these species, which perform unique functions within the global ecosystem, may ironically wind up being a driver of change as well.
The researchers hope future studies will further explore the long-term effects of species extinction on habitats and ecosystems.
Photo, posted April 6, 2013, courtesy of Nic Trott via Flickr.