A Recount of Tropical Tree Species

Abstract

If aliens visited earth, perhaps they would wonder how many distinct life forms our planet has. With their advanced intellect and technology, they might well have the answer. It is clear from R. M. May's Perspective “Tropical arthropod species, more or less?” (2 July, p. [41][1]) that we do not. May inadvertently adds to the confusion by indicating that New Guinea is home to roughly one-third of tropical tree species. Given that about 6000 tropical tree species are from New Guinea ([ 1 ][2], [ 2 ][3]) out of 37,000 tree species in all rainforests ([ 3 ][4]), only about 16% of tropical tree species are from this region—about half the estimate provided by May. ![Figure][5] CREDIT: GERRY ELLIS/MINDEN PICTURES, GETTYIMAGES I agree with May's conclusion that taxonomy needs more recognition, but we also need more of taxonomists' rigor, lest we confound what is already a challenging task. Without this rigor, our alien visitors might consider our science to be less dismal, as May suggests, but more careless. 1. [↵][6]1. R. Hoft , Plants of New Guinea and the Solomon Islands: Dictionary of the Genera and Families of Flowering Plants and Ferns (Wau Ecology Institute, Wau, Papua New Guinea, 1992). 2. [↵][7]1. B. J. Conn, 2. K. Q. Damas , Guide to Trees of Papua New Guinea (2006); [www.pngplants.org/PNGtrees][8]. 3. [↵][9]1. J. Ghazoul, 2. D. Sheil , Tropical Rain Forest Ecology, Diversity, and Conservation (Oxford Univ. Press, Oxford, 2010). [1]: /lookup/doi/10.1126/science.1191058 [2]: #ref-1 [3]: #ref-2 [4]: #ref-3 [5]: pending:yes [6]: #xref-ref-1-1 View reference 1 in text [7]: #xref-ref-2-1 View reference 2 in text [8]: http://www.pngplants.org/PNGtrees [9]: #xref-ref-3-1 View reference 3 in text