hare, giant otter, and large rodents and shrews; Sardi- 

 nia also had pygmy elephants, dwarf pig, small ante- 

 lope, and macaque monkeys. The Balearic Islands had 

 a small, unique antelope-goat (sometimes called a 

 "mouse-goat"), giant dormice, large shrews, and giant 

 tortoises. 



These animals were able to reach islands from the 

 mainland either by swimming or on natural rafts. The 

 reason for such migration is not clear, hut it may have 

 been due to overpopulation on the mainland and/or to 

 decreased food sources. Such colonization would have 

 been very rare, and, as a result, the new population 

 would have been numerically small. Over time, the 

 dwarf and giant forms evolved on these islands, derived 

 from their normal-sized mainland ancestor. Even dur- 

 ing the Pleistocene glaciations, when sea levels were 

 lowest, Cyprus remained separated from the now sub- 

 merged Gulf of Alexandretta, on the coast of Turkey, 

 by about 20 miles. 



In general, larger mammals become smaller, while 

 rodents, tortoises, and some birds become larger. 

 Dwarfism/gigantism is a common phenomenon on is- 

 lands which lack large ground-living carnivores and 

 which are far enough from the mainland not to receive 

 continuing colonizers. The small size of these once- 

 large mammals gave them greater mobility in moun- 

 tainous island environments. It also enabled them to 

 more efficiently utilize their food sources, thus permit- 

 ting a larger population. Their smallness also made it 

 easier tor them to regulate their body temperatures (a 



proportionally larger body surface facilitates heat ex- 

 change). 



The once-large mammals exhibit definite bone fu- 

 sion (syndactyly) and bone shortening in their lower 

 limbs; they also have relatively heavier built legs with 

 stouter bones. The Cypriot hippo moved its limbs pri- 

 marily in the fore-aft direction, sometimes called "low- 

 gear" locomotion, but could not move them sideways. 

 This suggests that, unlike its mainland ancestor, it was 

 better adapted to walking than to swimming. The Cyp- 

 riot and Cretan hippos have also lost their foot pads; 

 they apparently walked on the tips of their toes. This 

 would have allowed them greater mobility and agility 

 in the mountainous environment. All dwarfed hippo- 

 potami have their eyes and nose on a lower plane than 

 the modern African hippopotamus. These positions 

 suggest that the dwarfed hippopotami are spending 

 more time on dry land than in the water. The Cypriot 

 hippopotamus also exhibits changes in the pattern of 

 the skull bones, the number and shape of the teeth 

 (lophodont, i. e. , with molars adapted for grinding) and 

 wear pattern of the jaws. All this evidence suggests that 

 the hippopotamus had a mode of life somewhat like a 

 leaf-eating pig. 



Both the dwarfed deer and antelope-goat have 

 fused and shortened foot bones (metapodials and pha- 

 langes), which are also characteristic of "low-gear" 

 locomotion. This suggests that movement was res- 

 tricted to a mere amble instead of the quick speed found 

 in their larger ancestors. With no predators to evade, 



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