Wednesday, August 10, 2011

Drastic Ecological Change brought About by Columbus Part Two

Hutton Archive /Getty Images

I wanted to share some more fascinating stories from Charles Mann's fascinating interview with Terry Gross on Fresh Air about his new book "1493:Uncovering the New World that Columbus Created". He is an excellent oral as well as written storyteller with the historical research to back it up.
Most of us think of the slave trade as being confined to Africa but the Peruvians brought Chinese slaves to their land, as related in one of Charles Mann's stories. The Chinese thought they we going to the gold fields of California but instead they were brought to the islands off the coast of Peru for the hideous job of harvesting bird dung guano. 
When I lived on Charlotte Harbor in Punta Gorda, Florida there was a mangrove island (one of many) that the seabirds congregated on and it was fascinating to watch the multitude of birds there, but we kept a wide berth on our kayaks, as the stench was overwhelming from all their guano.

The Asians that were brought to harvest the guano, on the Peruvian islands, had horrific working conditions as guano is full of ammonia crystals that would constantly burst, especially as the dung was shoveled into the pits, forcing them to constantly breathe toxic corrosive fumes. This guano trade launched modern agriculture as its export fostered the use of high input fertilizers. Peru was the source of a wide variety of native potatoes of all kinds and colors. Thus the guano brought from Peru to Europe contained potato blight. The Europeans and especially the Irish focused on monoculture unlike the Peruvians, growing a single high-yield variety of potato. Because of this the potato blight killed off the potato crop in a matter of weeks in Ireland causing millions to die of starvation and a mass migration. Ireland is still affected by this cataclysmic event as the population is now less than 150 years ago before the blight. 
Malaria brought to the New World via mosquitos and humans carrying the parasite and then bitten by New World mosquitos, also had a huge effect on the culture of the New World. Black slaves coming from Africa were genetically more immune with the sickle cell anemia gene. Heat fosters malaria as it gives the disease a longer window to flourish in the mosquito's system. Right around the District of Columbia and south is the ideal climate for malaria to burgeon and this actually had a role in creating the Mason Dixon LIne and the desire for black slaves to work the fields, with a their ability to survive the difficult climate and working conditions of the south. And as far as the wealthy slave owners were concerned think Tara in "Gone with the Wind" with the mansion on the hill surrounded by lawns instead of forest with tall windows for breezes insulating them from the more mosquito filled swamps and lowlands. Malaria has become a rarity in the south with the advent of DDT (despite its ill effects on bird populations etc) and the draining of swamps and wetlands and more sophisticated drug treatments. 
Malaria was still an issue in the United States in the 20th century. A parasitologist named Dr. Parrish told me about his childhood growing up in Louisiana. Atabrine was the drug of choice for malaria in those days before the parasite became drug-resistent and it is also a yellow dye. He said if you made a right turn into the town in Louisiana where he grew up you would think you were in China, as all of the residents had a yellowish green tinge from the atabrine. Having contracted parasites myself many years ago I experienced this phenomenon and looked like I was from Mars. Friends who had not seen me in a while did not know what to make of it and still remember seeing me looking like that. Luckily the color is not permanent!
My uncle told me about the vast profusion of songbirds in Florida before the advent of DDT which alas are no more. They began spraying DDT when he was a child. My grandfather had a luscious tropical garden in Pass-a-Grille with a small pond. They wanted to spray the pond and he would not give them access but my uncle swore that they sprayed it anyway and the bird population plummeted along with their beautiful songs. I remember binoculars in the bathroom window that overlooked the pond and birdbath. Alas we will probably never know what all that variety of birdsong sounded like. 

Malaria is a mosquito-borne infectious disease of humans caused by eukaryotic protists of the genus Plasmodium. It is widespread intropical and subtropical regions, including much of Sub-Saharan AfricaAsia and the Americas. Malaria is prevalent in these regions because of the significant amounts of rainfall and consistent high temperatures; warm, consistent temperatures and high humidity, along with stagnant waters in which their larvae mature, provide mosquitoes with the environment needed for continuous breeding.[1] The cause of the disease is a protozoan, discovered in 1880 by Charles Louis Alphonse Laveran; while he was working in the military hospital inConstantine, Algeria, he observed the parasites in a blood smear taken from a patient who had just died of malaria.[2] The disease results from the multiplication of malaria parasites within red blood cells, causing symptoms that typically include fever and headache, in severe cases progressing to coma, and death.
Four species of Plasmodium can infect and be transmitted by humans. Severe disease is largely caused by Plasmodium falciparum. Malaria caused by Plasmodium vivaxPlasmodium ovale and Plasmodium malariae is generally a milder disease that is rarely fatal. A fifth species, Plasmodium knowlesi, is a zoonosis that causes malaria in macaques but can also infect humans.[3][4]
Malaria transmission can be reduced by preventing mosquito bites by distribution of inexpensive mosquito nets and insect repellents, or by mosquito-control measures such as spraying insecticides inside houses and draining standing water where mosquitoes lay their eggs. Although many are under development, the challenge of producing a widely available vaccine that provides a high level of protection for a sustained period is still to be met.[5] Two drugs are also available to prevent malaria in travellers to malaria-endemic countries (prophylaxis).
A variety of antimalarial medications are available. In the last 5 years, treatment of P. falciparum infections in endemic countries has been transformed by the use of combinations of drugs containing an artemisinin derivative. Severe malaria is treated with intravenous or intramuscular quinine or, increasingly, the artemisinin derivative artesunate [6] which is superior to quinine in both children and adults.[7]Resistance has developed to several antimalarial drugs, most notably chloroquine.[8]
Each year, there are more than 225 million cases of malaria,[9] killing around 781,000 people each year according to the World Health Organisation's 2010 World Malaria Report,[10] 2.23% of deaths worldwide. The majority of deaths are of young children in sub-Saharan Africa.[11] Ninety percent of malaria-related deaths occur in sub-Saharan Africa. Malaria is commonly associated with poverty, and can indeed be a cause of poverty[12] and a major hindrance to economic development.
Mangroves are various kinds of trees up to medium height and shrubs that grow in saline coastal sediment habitats in the tropics andsubtropics – mainly between latitudes 25° N and 25° S. The word is used in at least three senses: (1) most broadly to refer to the habitat and entire plant assemblage or mangal,[1] for which the terms mangrove forest biomemangrove swamp and mangrove forest are also used, (2) to refer to all trees and large shrubs in the mangal, and (3) narrowly to refer to the mangrove family of plants, the Rhizophoraceae, or even more specifically just to mangrove trees of the genus Rhizophora.
The mangrove biome, or mangel, is a distinct saline woodland or shrubland habitat characterized by a depositional coastal environments, where fine sediments (often with high organic content) collect in areas protected from high-energy wave action. Mangroves dominate three quarters of tropical coastlines.[2] The saline conditions tolerated by various mangrove species range from brackish water, through pureseawater (30 to 40 ppt), to water concentrated by evaporation to over twice the salinity of ocean seawater (up to 90 ppt).
DDT (from its trivial namedichlorodiphenyltrichloroethane) is one of the most well-known synthetic pesticides. It is a chemical with a long, unique, and controversial history.
First synthesized in 1874, DDT's insecticidal properties were not discovered until 1939, and it was used with great success in the second half of World War II to control malaria and typhus among civilians and troops. The Swiss chemist Paul Hermann Müller was awarded theNobel Prize in Physiology or Medicine in 1948 "for his discovery of the high efficiency of DDT as a contact poison against several arthropods."[2] After the war, DDT was made available for use as an agricultural insecticide, and soon its production and use skyrocketed.[3]
In 1962, Silent Spring by American biologist Rachel Carson was published. The book catalogued the environmental impacts of the indiscriminate spraying of DDT in the US and questioned the logic of releasing large amounts of chemicals into the environment without fully understanding their effects on ecology or human health. The book suggested that DDT and other pesticides may cause cancer and that their agricultural use was a threat to wildlife, particularly birds. Its publication was one of the signature events in the birth of theenvironmental movement, and resulted in a large public outcry that eventually led to DDT being banned in the US in 1972.[4] DDT was subsequently banned for agricultural use worldwide under the Stockholm Convention, but its limited use in disease vector control continues to this day and remains controversial.[5][6]
Along with the passage of the Endangered Species Act, the US ban on DDT is cited by scientists as a major factor in the comeback of thebald eagle, the national bird of the United States, from near-extinction in the contiguous US.

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