Peter Hamilton Raven, the botanist who ran the Missouri Botanical Garden for forty years and turned it into a clearinghouse for the species the world was losing, died on April 25 at his home in St. Louis. He was 89. [1] Raven was born in Shanghai in 1936 to American parents and grew up in San Francisco, where he joined the California Academy of Sciences as a teenager. He took his bachelor's at Berkeley in 1957 and his PhD at UCLA in 1960, on the genus Camissonia. [2]

He arrived at the Missouri Botanical Garden in 1971 as director and stayed until 2010, by which point the garden had become a research institution as much as a public collection — fielding floras of California, Mexico, Madagascar, and most consequentially the multi-volume Flora of China, a thirty-three-year collaboration with Beijing's Institute of Botany. [2] He published more than seven hundred papers and books and trained a generation of plant taxonomists. The 1964 paper with Paul Ehrlich, "Butterflies and Plants: A Study in Coevolution," coined the word coevolution and rewrote the question. [2]

Raven turned the language of biodiversity into a register of accountability. He talked about loss in numbers that carried — twenty percent of plant species likely gone within a human lifetime if current trends held — and he refused to soften the math when audiences flinched. He won the National Medal of Science in 2000, the Tyler Prize in 1994, the International Prize for Biology in 1986, and the MacArthur in 1985. [2] He served on Bill Clinton's Committee of Advisors on Science and Technology and on the board of the National Geographic Society.

He is survived by his wife, Patricia Duncan, and four children. [1]

The lichen Ocellularia raveniana and the genus Megacorax carry his name. The Missouri Botanical Garden carries his tenure. The species he counted carry the rest of it.

-- DARA OSEI, London