Kutschera Ulrich, Kleinhans Simon
Institute of Biology, University of Kassel, Heinrich-Plett-Str. 40, 34132, Kassel, Germany,
Theory Biosci. 2013 Dec;132(4):259-65. doi: 10.1007/s12064-013-0193-4. Epub 2013 Aug 24.
The Galápagos Islands (Ecuador) are usually associated with the explorations and theoretical deductions of Charles Robert Darwin (1809-1882), but Alfred Russel Wallace (1823-1913) also investigated these islands and published several reports on the living world of this unique archipelago. In contrast to Darwin, Wallace described the destruction of natural ecosystems by humans and foresaw the resulting extinction of species. Here, we outline two case studies pertinent to Wallace's prediction. First, we summarize the behavior of the predator-naive marine iguanas (Amblyrhynchus cristatus) on the Galápagos Islands, which are threatened by feral dogs and cats imported by humans. We also describe the unique life cycle of the spiny-tailed iguana (Ctenosaura bakeri) from the island of Utila (Honduras), a rare species whose populations are declining because of habitat destructions. In contrast to these threatened, endemic island species, the Green iguana (Iguana iguana) is still widely distributed, although, as a result of de-forestation, in some areas of South America local populations have disappeared. We conclude that Wallace was correct in his prediction that, because of human activities, numerous species of animals and plants will be driven to extinction, notably on islands.
加拉帕戈斯群岛（厄瓜多尔）通常与查尔斯·罗伯特·达尔文（1809 - 1882）的探索和理论推论相关联，但阿尔弗雷德·拉塞尔·华莱士（1823 - 1913）也对这些岛屿进行了研究，并发表了多篇关于这个独特群岛生物世界的报告。与达尔文不同的是，华莱士描述了人类对自然生态系统的破坏，并预见了由此导致的物种灭绝。在此，我们概述两个与华莱士的预测相关的案例研究。首先，我们总结了加拉帕戈斯群岛上对捕食者毫无防备的海鬣蜥（海鬣蜥属）的行为，它们受到人类引入的野狗和野猫的威胁。我们还描述了来自洪都拉斯乌蒂拉岛的刺尾鬣蜥（贝克栉尾蜥）独特的生命周期，这是一种稀有物种，其种群数量因栖息地破坏而正在减少。与这些受到威胁的岛屿特有物种不同，绿鬣蜥（美洲鬣蜥）仍然广泛分布，不过，由于森林砍伐，在南美洲的一些地区其当地种群已经消失。我们得出结论，华莱士的预测是正确的，即由于人类活动，众多动植物物种将被推向灭绝，特别是在岛屿上。
