Evidence collected by researchers at the University of Cape Town over a 23-year period show that animals’ body sizes are shrinking in response to climate change.
The study, led by Associate Professor Res Altwegg, evaluated the relationship between the body mass of mountain wagtails, a bird native to South Africa, and temperature between 1976 and 1999.
The researchers found that as temperatures rise, the wagtails’ average body mass decreased to improve their survivability. They concluded that this is one of the first demonstrations of the selective forces that underlie trends like decreasing body mass.
The findings are becoming increasingly relevant as global temperatures are rising faster than ever before, with a global increase of 1 degree Celsius in the past 100 years.
This study adds to research which has shown that animals are moving to new environments to avoid climate change. Adding to the knowledge of how climate change is affecting animals, scientists may be able to understand the effects on whole ecosystems and how these changes will affect humans.