If you would like a good grasp of Earth's sixth mass extinction, the link below explicitly explains the urgency of it in graphic terms. The scholarly article is relatively short, well illustrated, and right on the mark. Are you pressed for time? At least scroll down a bit at the link to Figures 2 & 3, (especially Fig. 2) and don't just glance at them. Study the "key" at the bottom of each one, and then the three different columns of each Figure.
http://www.ceres.ens.fr/IMG/pdf/ceballos-etal-2017-pnas.pdf
Some people (even some who should know better) don't believe there is an ongoing sixth mass extinction. Furthermore, they don't see biodiversity loss as being of any major importance to humans. Most likely, that's because they don't yet see any large numbers of individual species going extinct, and they aren't considering the decline of populations as important or significant. Finally, they apparently don't understand the role of biodiversity in natural ecosystems, or how human survival is related to those ecosystems.
In biology, a population is a group of similar organisms (e.g., mammals, birds, amphibians, etc.) or often, a specific species (e.g., Canis lupus). Population studies of any group of organisms are done in a particular geographic area. Populations exist in specific areas. So, for example, the arctic fox is not found in the tropics. :)
Prior to any species going forever extinct, there's a significant decline in their population numbers. The decline happens in different areas, and rates of decline may vary from place to place. If the decline continues, ultimately the inevitable result is extinction.
The point being: simply because species are not yet totally disappearing in massive numbers in no way means a mass extinction is not underway. Why does it not mean that? Because declines in populations precede final extinction, and currently, population declines are significant. For example, since 1970 the worldwide populations of wildlife vertebrates on land have declined by 68%. It's even worse in aquatic habitats. [Source: Living Planet Report 2020, by the World Wildlife Fund.]
That's a wake-up call.
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Not only my opinion. Be Well
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