Foster's rule
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Foster's rule, also known as the island rule or the island effect, is an ecogeographical rule in evolutionary biology stating that members of a species get smaller or bigger depending on the resources
Garganornis ballmanni, a very large fossil goose from the Gargano and Scontrone islands of the Late Miocene
Insular dwarfism
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Insular dwarfism, a form of phyletic dwarfism, is the process and condition of large animals evolving or having a reduced body size when their population's range is limited to a small environment, pri
Foster's rule
…to their mainland varieties. Foster proposed that certain island creatures evolved larger body size (insular gigantism) while others became smaller (insular dwarfism). Foster proposed the simple explanation that smaller creatures get larger when predation pressure is relaxed because of the absence of some of the…
Skeletons of the extinct Palaeoloxodon falconeri, native to Sicily and Malta, it is one of the smallest known species of dwarf elephant. Adult males measured about one meter (3.3 ft) in shoulder height and weighed about 250 kg (550 lb). Females were smaller.
Europasaurus skull
Rapetosaurus BW
Lirainosaurus