In 1964, Paul Colinvaux began his life’s work—trying to understand the ice-age climate of the Amazon through mud cores and the pollen found within. Having sharpened his drill in the Arctic, the ecologist looked south to “terra incognita.” When he began his effort, no ice-age deposit or site in the Amazon had been identified.
Then in 1969, ornithologist Jurgen Haffer proposed a hypothesis to explain the Amazon’s vast biodiversity. During the last ice age (which peaked about 21,000 years ago), he suggested, most of the forest became arid grassland. In pockets of surviving greenery, speciation occurred. The new species repopulated the forest when it returned, contributing to its diversity.
Despite a lack of evidence, the refuge hypothesis gained appeal. Colinvaux’s mission took on new meaning. He had the tools to unravel an idea that was quickly becoming a paradigm, and his field data suggested ecological consistency rather than change. “Might not one of the secrets of the Amazon lie here in this history of tolerance and stability?” Colinvaux asked himself.
Colinvaux carries readers along on his adventure to uncover the Amazon’s ice-age mysteries—chronicling events, endeavors and emotions every step of the way. The strength of his story comes in his ability to highlight science as a process. He has many false starts, and he encounters barrier after barrier.
Even after Colinvaux collects the data he needs to prove his case, his tale does not immediately transition to one of triumph. The refuge hypothesis does not lie down. “Resulting bruises to the soul can be soothed by the Band-Aid of thought that says, ‘We were pioneers,’” he concludes, pushing onward.
Yale Univ. Press, 2008, 308 p., $32.50.