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" "Si queremos que el mundo escape de las temibles consecuencias del crecimiento de la población global y de los diez mil o doce mil millones de personas en el planeta a finales del siglo XXI, debemos inventar medios seguros y más eficientes de cultivar alimentos, con el consiguiente abastecimiento de semillas, riego, fertilizantes, pesticidas, sistemas de transporte y refrigeración. También se necesitarán métodos contraconceptivos ampliamente disponibles y aceptables, pasos significativos hacia la igualdad política de las mujeres y mejoras en las condiciones de vida de los más pobres.
Carl Edward Sagan (9 November 1934 – 20 December 1996) was an American astronomer, planetary scientist, cosmologist, astrophysicist, astrobiologist, author, and science communicator. His best known scientific contribution is research on extraterrestrial life, including experimental demonstration of the production of amino acids from basic chemicals by radiation. Sagan assembled the first physical messages sent into space, the Pioneer plaque and the Voyager Golden Record, universal messages that could potentially be understood by any extraterrestrial intelligence that might find them. Sagan argued the hypothesis, accepted since, that the high surface temperatures of Venus can be attributed to, and calculated using, the greenhouse effect. He testified to the US Congress in 1985 that the greenhouse effect will change the earth's climate system.
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In both countries, what passes for public debate is still, on closer examination, mainly repetition of national slogans, appeal to popular prejudice, innuendo, self-justification, misdirection, incantation of homilies when evidence is asked for, and a thorough contempt for the intelligence of the citizenry.
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