Unveiling global species abundance distributions - PMC To test this assumption we used birds, the only taxonomic group for which for the most species abundance estimates exist and correlated the number of GBIF records for each species with the estimated global abundance of birds from ref 25 (n = 9,047 species) and from BirdLife International (n = 3,216 species)
What is Background Extinction Rate and How is it Calculated? (A conservative estimate of background extinction rate for all vertebrate animals is 2 E MSY, or 2 extinctions per 10,000 species per 100 years ) As you can see from the graph above, under normal conditions, it would have taken anywhere from 2,000 to 10,000 years for us to see the level of species loss observed in just the last 114 years
Estimating the normal background rate of species extinction These estimates match those of Weir and Schluter , who estimated bird and mammal extinctions at 0 08 E MSY at the equator—where there are the most species—and at ∼0 4–0 6 E MSY at 50° latitude—where there are fewer species (They based their estimates on the ages of a large number of sister species divergences of New World birds and
New approaches narrow global species estimates for beetles . . . Using analogous approaches, we also produce independent estimates for all insects, mean: 5 5 million species (range 2 6–7 8 million), and for terrestrial arthropods, mean: 6 8 million species (range 5 9–7 8 million), which suggest that estimates for the world’s insects and their relatives are narrowing considerably
ENV 121 Chapter 11 Flashcards - Quizlet The total number of species that exist worldwide is estimated to be _____ between 8 million and 12 million After arachnids, what is the most endangered animal taxonomic group, with 34 percent of known species considered endangered?
Abundance does not predict extinction risk in the fossil . . . Mean longevity estimates for radiolarian species in previous literature vary from 4 8 31 to 12 9 my 35 The relatively short length of the EEP study interval (10 3 my) thus likely does not capture