This dynamic obviously mimics the successive wars of extermination humans conducted on land, against large mammals and other animals. The best studied of these was conducted 12 000–13 000 years ago by ‘Clovis’ hunters in North America, so named after the site where their fluted arrow points were first found. Contrary to earlier conventional wisdom, the Clovis people were not the ‘first Americans’, these probably having been coastal people, who may have relied on fishing for their subsistence (Erlandson 2002). The Clovis people, by contrast, were apparently the first to tackle the large mammals of the interior. Archaeology and model studies confirm that their decimation of 30 species of large and slow-reproducing mammals (mastodon, giant ground sloth, giant armadillo, western camels, etc.) proceeded in the form of a giant wave sweeping across North America over a period of 800 to 1600 years (Alroy 2001). Given the difficulty preliterate societies can be expected to have in conveying quantitative information on animal abundance across generations (Pauly 1995), this timespan was sufficient for the Clovis hunters living past the crest of this wave to fail to realize what their ancestors had done and lost (Alroy 2001), a problem still occurring now, in the form of ‘shifting baselines’ (Pauly 1995).
Ironically, there are those who, despite the evidence provided by numerous Clovis points embedded in the bones of fossil mammals, still argue that it is ‘climate change’ that drove these 30 species to extinction. Here, environmental changes are supposed to have eliminated, in a few centuries, species that had endured millions of years of, yes, environmental change, including glaciations that covered the northern part of North America under 2 km of ice.
There is good evidence of a similar mammalian hecatomb 40 000–50 000 years ago in Australia, in this case associated with the very first arrival of Homo sapiens, who exterminated, over a short period, the larger representatives of the marsupial fauna that had evolved over millions of years on that continent (Roberts et al. 2001).
Our last example is the extermination of the large, ostrich-like moa in what is now New Zealand, by the ancestors of the present-day Maori, who arrived from Polynesia in the late thirteenth century, and who took only ca. 100 years to exterminate 11 species that had lived in the area for millions of years (Holdaway & Jacomb 2000).
In the marine realm, the serial depletions of large coastal animals, documented, for example, in Jackson et al. (2001), accelerated with the development, during the Industrial Revolution, of vessels of unprecedented fishing power, such as stream trawlers. Added to the substantial, pre-existing fishing effort of the rowed and sailed craft that tended to operate inshore, these industrial vessels, targeting stocks of larger fishes further offshore, quickly reduced populations that had previously been perceived as immune to the effects of fishing (Cushing 1988; Myers et al. 1997). Denial is, however, still rampant, sometimes taking absurd forms, as illustrated here by a representative of the French fishing industry recently asserting, for the demersal resources around France, that ‘the stocks are not declining, they are changing location’ (translation of the title of Bigot 2002).
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