Insularity and Its Effect on Mammal Evolution

Origination and extinction patterns of mammals in three central Western Mediterranean islands from the Late Miocene to Quaternary

“…4. The scarcity of large carnivores on islands has long been connected with carnivores' inability to disperse on islands (Sondaar, 1977(Sondaar, , 1987. Surviving and adapting to the island ecosystems may be particularly demanding for predators (Van der Made, 1999).…”

Was southern Central America an archipelago or a peninsula in the middle Miocene? A test using land-mammal body size

“…At one end of the spectrum, the fox-sized Miocene insectivore Deinogalerix koenigswaldi from the Gargano peninsula of Italy (which was an island during the Neogene) is the largest insectivore ever reported, extinct or living (Freudenthal, 1972). In contrast, the tiny elephant Elephas falconeri from the Pleistocene of Sicily is about four times smaller in skull size than its congener, and presumed ancestor, E. namadicus from the adjacent mainland (Sondaar, 1977). Size reduction in extinct proboscideans is in fact pervasive in island faunas.…”

Relationships of Megaoryzomys curioi, an Extinct Cricetine Rodent (Muroidea: Muridae) from the Galápagos Islands, Ecuador

“…This possibility is in harmony with the closer resemblance of Megaoryzomys to the larger species of Thomasomys than to the smaller species. Insular gigantism in rodents is generally attributed to the following causes (Sondaar, 1977;Wassersug et al, 1979, and references therein): (1) predator avoidance, (2) drift toward larger size in the absence of predators because of no need to avoid them, (3) interspecific competition with other rodents, (4) selection for larger size in the absence of larger herbivores, regardless of the presence or absence of other rodents. Some combination of any of these reasons may have been involved in the attainment of large size in Megaoryzomys.…”