Comments by "Old Scientist" (@OldScientist) on "We need IMMEDIATE action to stop extinction crisis, David Attenborough - BBC" video.

  1. This is a scare story about things you cannot see. Extinction rates (1500-2009) peaked around 1900 at 50 per decade. Extinction rates have declined dramatically to around 4 to per decade in the 2000s. So the extinction rate is very low: 908 known lost species for 2.1 million known species in 500 years (IUCN Red List), so from observations there are an average of slightly less than 2 species lost every year. Out of a known species total of over 2 million. That gives an annual percentage loss of less than 0.0001%. That's background extinction. At that frequency it will take over 930,000 years to reach 80% extinction of species experienced at the K-T boundary that saw the extinction of the dinosaurs. Of course, extinction is a natural part of the evolution of life on this planet with the average lifespan of a species thought to be about 1 million years (cf 930,000). It is estimated that 99.9% of all plant and animal species that have existed have gone extinct. It should also be noted that no taxonomic families have become extinct in the last 500 years. In fact marine diversity at the taxonomic level of families is the highest it has ever been in the Earth's long history (see Sepkoski Curve). In a review of 16,009 species, most populations (85%) did not show significant trends in abundance, and those that did were balanced between winners (8%) and losers (7%) (Dornelas et al, 2019). There have been only 9 species of continental birds and mammals confirmed extinct since 1500 (Loehle, 2011). No global marine animals have become extinct in the past 50 years (McCauley et, 2015 using IUCN data). Take bird species: 11,195 have been counted (not estimated). All of these have been assessed by the IUCN. They catalogued 4 bird species became extinct over the course of 28 years between 1988 and 2016. That's 1.4 per decade or an annual extinction rate of 0.001%. Also the proportion of species assessed as threatened by the IUCN has declined rapidly over time, from 65% in 2000 (11,000 out of 17,000) to 28% in 2024 (46,000 out of 166,000). This increasingly positive outcome of their species assessments is only accelerating as time passes. Using IUCN data on assessed species- Amphibian species extinct 0.009% per decade. Mammals 0.029% per decade. Reptiles 0.006% per decade. Fish 0.006% per decade. Insects 0.009% per decade. There is no climate crisis.
    1