| Comments |
P.3.5 bottom paragraph: "Nonetheless, the central tendencies of background plant extinction rates fall mostly in the range 0.05–0.15 species per million species per year (S/MSY) (see Table 1), whereas background speciation rates (based on the same data sources) fall mostly in the range of 0.1–1.0 S/MSY (Table 1)." P.3.7 top paragraph: "There is thus massive uncertainty with respect to undocumented extinctions and
unknown extant populations of rare species. Nonetheless, if [investigators] take 142 and 592 as somewhere in the ballpark of extinctions that have occurred between 1600 and 2016, [they] get extinction rates of 0.98–4.1 (Table 1, see also primary source 81), 1–2 orders of magnitude higher than the background rate." P.3.7 2nd paragraph: "A key point for [investigators'] purposes here is that even if [they] take a low-end estimate of 5% extinction (primary source 82) and assume a 1,000-year period over which these extinctions occur, the estimated extinction rate (50 S/MSY) is upward of 1,000 times the background rate (see Table 1). The time course of extinctions may well exceed 1,000 years (ref 23), but other factors, such as climate change, might also push extinction rates even higher (refs 44, 107)." See notes beneath table |