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Saturday, January 02, 2010

Ecological Imperialism

A book review

by Rhonda L Tintle (April 2005)

In his book, Ecological Imperialism: The Biological Expansion of Europe, 900-1900, Alfred W Crosby investigates the roots of European domination over the western world. He calls the places where early Europeans settled "Neo-Europes" with special emphasis on North and South America, Australia, and New Zealand. In his prologue he ponders whether Europeans dominated their environment and other cultures because of their technology, or whether the consistent "success of European imperialism has a biological, [and] an ecological, component" (7). Crosby's thesis is that Europeans were successful imperialists because wherever they went their agriculture and animals thrived; and the indigenous populations and local ecosystems collapsed under their biological advance.

Crosby begins at the beginning, discussing the one big continent, Pangaea, supposed to have existed in pre-history and the slow development of life forms other than reptilian, in particular Homo sapiens. The break up of Pangaea (this hypothetical super-continent) caused the "the decentralization of the process of evolution", that is, when the land cracked apart flora and fauna were spilt between the newly created continents. That continental split is the reason similar species are found in Europe and North America (11-12).

Eventually Crosby brings the reader up to the end of the Ice Age. Ten thousand years ago humans were exploring the islands of the Eastern Atlantic including Australia. Once on these islands humans domesticated plants, piled up mounds of garbage, spread disease, and hunted animals into extinction. Normally the despoilment of indigenous flora and fauna occurs over tens of thousands of years. In locations where humans arrived with mature hunting skills a sudden extinction of local plant and animal life occurred. These sudden prehistoric, or Pleistocene, overkills were the first concentrated impact humans had on virgin ecosystems.

The virgin ecosystem of Porto Santo Island was the destination of Portuguese settlers during the 1400s. Porto Santo Island was completely uninhabited and filled with untouched flora and fauna. One Portuguese ship captain brought a mother rabbit and her babies to the island. The rabbits loved Porto Santo and thrived in the island environment. So much so that soon the settlers were blasting away at the rabbits in an attempt to exterminate the entire local rabbit population. It seems the rabbits could not determine the difference between the crops meant for human consumption and the crops meant for bunny consumption. The rabbits won in this instance and for a time the settlers moved elsewhere, "defeated by their own ecological ignorance" (75).

The experience of Spanish invaders in the Canaries showed them that no matter where they went, even if they could not out-fight their opponents, Europeans could dominate their enemies anyway. "In all these [new] places, the newcomers would conquer the human populations and Europeanize entire ecosystems". The Spanish learned from their experiences in the Canaries that their livestock and crops would succeed in these new environments; they also learned they could easily defeat the local natives without traditional warfare. The various "plagues" and "sleeping sicknesses", which the Spanish called peste and modorra, killed off and weakened natives who had no natural immunity to ailments common to the Spanish. In essence, sore throats and colds were the winning weapons of the conquerors; it was the flu that subjugated the Canaries (92-95).

The unfortunate natives of the Canary Islands, the Guanches, did not survive their meeting with the Spanish sailors. These previously isolated people died rapidly from dysentery, pneumonia, and venereal disease. According to Crosby "few experiences are as dangerous to a people's survival as the passage from isolation to membership in the worldwide community that included European sailors, soldiers, and settlers" (99). When the Spanish conquered the Canaries the Guanches lost their land and therefore their livelihood. Some Guanches joined the Spanish army and went to fight in the Americas; the Spanish sold others into slavery. The majority of Guanches however died of disease and the entire population became extinct (97-99).

Unlike the Guanches of the Canaries, the Maoris of New Zealand did survive despite great odds. When invaded by Europeans the Maoris assumed they would become extinct. European rats annihilated the Maori rat, an animal that was a food staple for the natives. The Maori fly might have help ward off the incursion of sheep that quickly destroyed the local flora, but invading European houseflies wiped out the local flies. Clover took over where ferns had been, and the Maori waited for their own extinction. The Maori population hit bottom in 1890 but then began a mysterious recovery and 280,000 people claim to be Maori by 1981 (266-268).

In the 1500s Europeans arrived in the Americas with horses, technology (weapons), domesticated plants (crops), farm animals, germs, insects, diseases, weeds, and varmints. The garbage piled up by farmers encouraged varmint populations (mainly mice and rats) which spread disease and attacked human food supplies (29-30). Crosby devoted an entire chapter to the spread of weeds around the world. Weeds are not specific plants. "Weed" is a general term applied to a plant that spreads rapidly and encroaches on other plants. The study of where specific weeds appeared and when, aids in tracking population movements. The weeds brought by Europeans were actually another unintentional imperial victory. Weeds repaired damaged top soils and provided feed for livestock. "Rye and oats were once weeds" (149). "Weeds are the Red Cross of the plant world; they deal with ecological emergencies" (169). "Weeds thrive on radical change, not stability. That, in the abstract, is the reason for the triumph of European weeds in the Neo-Europes ..." (170). Weeds were resilient and thrived in soils laid bare by European plows, and damaged by drastically altered ecosystems.

European populations exploded in the Americas and Australia. What distinguished these Neo-Europes were the large food surpluses they generated. Neo-Europes led the world in food production "relative to the amount locally consumed" (4). Other cultures actually produced more food per capita and per hectare, but the Neo-Europes exported more food than any other society. Especially successful exports from Neo-Europes were wheat, soybeans, pig products, and beef. Europeans consistently chose to settle in temperate climates where their animals and crops thrived. This was prudent and logical, it would have made no sense for Europeans to settle in torrid climates where their livestock would have suffered, and their favorite crops could not be grown.

The wind also aided European imperialists. When faced with strong winds the Portuguese marinheiros, true sailors, did not turn around and go home or sit sail-less in the water until the winds changed. Marinheiros would "sail around the wind". Sailors would tack close enough to the contrary wind to keep moving and then find a wind that they could use to continue their course. The Portuguese who perfected this "crabwise slide" called it the volta do mar, literally "going back to the sea". This understanding of winds allowed marinheiros to sail out on trade winds and back home on the westerlies (116-119).

Smallpox was the big killer of the Aztecs and the Incas in Peru; the Huron and Iroquois in Mexico; and the Amerindians of the United States. Crosby claims the victories of the Conquistadors over the Amerindians were "in large part the triumphs of the virus of smallpox" (200). Besides smallpox Europeans brought dysentery and influenza; those epidemics killed almost the whole indigenous population of North America. In effect, the domination over ecology and culture by European invaders was more of a biological accident, than a well-executed military takeover.

Virgin soil epidemics spread through populations who had no prior contact with European diseases. These populations had no immunity to protect them. Virgin soil epidemics had many dramatic consequences. First, the epidemics effectively committed genocide, killing entire populations of native people around the world. Second, certain diseases (measles, influenza, tuberculosis) effected people fifteen to forty years of age more than others. These young adults were responsible for most of the labor involved in supplying food, procreation, raising children, and defending the society. The third and fourth effects of virgin soil epidemics were cultural optimism on the part of the conquerors, and cultural fatalism on the part of the conquered. When Europeans arrived and slew their rivals without raising a sword they believed that God must be on their side and this belief affirmed the rightness of their imperialistic actions. When the indigenous people died by the hoard from mysterious ailments they developed a fatalistic view of their own destiny and supposed the white man's Gods were the more powerful.

Ecological Imperialism is interesting, occasionally humorous, and easy to read. Crosby accomplishes his goal of writing a big book. This author presents a convincing and encompassing explanation for the incredible success of European imperialists. The book leaves the reader with more questions. How aggressively imperialistic were the original conquerors if all they had to do was show up and their opponents fell to the wayside? Crosby argues convincingly that Europeans were triumphant because the places they chose to conquer had ecosystems and indigenous populations that surrendered to the biology of the invaders.


Crosby, Alfred W. Ecological Imperialism: The Biological Expansion of Europe, 900-1900. Cambridge University Press: New York, 1986.

Martin, Paul S. "Prehistoric Overkill". Quaternary Extinctions. University of Arizona Press:Tucson, 1984.

Copyright (c) 2005 by

Bill Totten


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