Higher extinction rates of insular mammals after arrival of modern humans.
Islands are biodiversity hotspots and home to animal species with unique features, including dwarfs that evolved to very small sizes compared to their mainland relatives, and giants. An international study now shows that those species have a higher risk of extinction. The findings are supported by a software developed by SIB’s Daniele Silvestro at the University of Fribourg. The study, published in Science, also shows that extinction rates of mammals on islands worldwide increased significantly after the arrival of modern humans.
In response to the unique characteristics of island environments, many organisms undergo remarkable evolutionary changes, among the most notable of which include extreme modifications of body size. This phenomenon is known as gigantism or dwarfism – in general, relatives of large continental species tend to become smaller on islands and small species tend to become larger. Some of these are already extinct evolutionary marvels such as dwarf mammoths and hippos that shrunk to less than one-tenth the size of their mainland ancestors, and rodents that increased by over 100-fold in size.
Extreme dwarfs and giants more likely to go extinct
Islands are biodiversity hotspots and home to animal species with unique features, including dwarfs that evolved to very small sizes compared to their mainland relatives, and giants. An international study now shows that those species have a higher risk of extinction. The findings are supported by a software developed by SIB’s Daniele Silvestro at the University of Fribourg. The study, published in Science, also shows that extinction rates of mammals on islands worldwide increased significantly after the arrival of modern humans.
In response to the unique characteristics of island environments, many organisms undergo remarkable evolutionary changes, among the most notable of which include extreme modifications of body size. This phenomenon is known as gigantism or dwarfism – in general, relatives of large continental species tend to become smaller on islands and small species tend to become larger. Some of these are already extinct evolutionary marvels such as dwarf mammoths and hippos that shrunk to less than one-tenth the size of their mainland ancestors, and rodents that increased by over 100-fold in size.
Extreme dwarfs and giants more likely to go extinct