While extinctions on Earth might be old hat, this is the first threat to biodiversity caused by a single species living on the planet itself. And the actions of that species—both past and present—have big, long-lasting consequences. A study published in Proceedings of the Royal Society B: Biological Sciences last week concludes that not only is the sixth extinction real, it may be further along that we expected.
“There is wide recognition that time is short for the integrated, ambitious actions needed to stop biodiversity loss by 2050,” writes Natural History Museum zoologist Richard Cornford along with other scientists. “This work shows that time is even shorter than had been thought.”
That’s because nature isn’t one to move quickly (evolution, after all, is measured in epochs). The deleterious effects experienced by Earth’s biodiversity today are likely the result of the poor environmental choices made by humans as long as 40 years ago. Where animals, such as small birds, might experience these effects within 13 years, larger animals will feel the hurt decades down the road. In other words, we are just now starting to hear the canary in the coal mine, even though it’s been chirping for years.
erowind wrote: ↑Fri May 05, 2023 5:17 am
The climate change thread probably covers this pretty well imo. I don't know that we need a new thread just for this topic.
I don't believe climate change covers extiction of animals. That is a completely different topic. Of course, one could help speed up the other but they're not the same.
It would clutter the climate thread. I think a focused thread to talk about extiction would be good.
erowind wrote: ↑Fri May 05, 2023 5:17 am
The climate change thread probably covers this pretty well imo. I don't know that we need a new thread just for this topic.
I don't believe climate change covers extiction of animals. That is a completely different topic. Of course, one could help speed up the other but they're not the same.
It would clutter the climate thread. I think a focused thread to talk about extinction would be good.
I'm going to move this thread to the Biology & Medicine forum as this is more about flora than climate.
To know is essentially the same as not knowing. The only thing that occurs is the rearrangement of atoms in your brain.
New study finds Almost half the world's species are seeing rapid population declines
Humans have already wiped out huge numbers of species and pushed many more to the brink – with some scientists saying we are entering a “sixth mass extinction” event, this time driven by humans.
The main factor is the destruction of wild landscapes to make way for farms, towns, cities and roads, but climate change is also an important driver of species decline and is predicted to have an increasingly worse impact as the world warms.
The study’s authors analyzed more than 70,000 species across the globe – spanning mammals, birds, reptiles, amphibians, fish and insects – to determine whether their populations have been growing, shrinking or remaining steady over time.
They found 48% of these species are declining in population size, with fewer than 3% seeing increases, according to the study published Monday in the journal Biological Reviews.
For decades, the extinction crisis has been defined by “conservation categories” – labels that the International Union for Conservation of Nature, a United Nations committee, assigns to each species they assess at a given moment in time, Pincheira-Donoso said.
Based on that method, the IUCN’s Red List of Threatened Species classifies about 28% of species as under threat of extinction.
“What our study shows is not whether species are currently classed as threatened or not, but instead, whether their population sizes are becoming rapidly and progressively smaller or not,” Pincheira-Donoso said. Downward trends in population over time are a precursor to extinctions.
According to this assessment, 33% of the species currently classed as “non-threatened” on the IUCN Red List are in fact declining towards extinction.
Over the past several decades, it has become clear that global biodiversity has been declining due to human activities including conversion of habitat, use of pesticides and herbicides and more recently, climate change. It is not known how many species are extinct due to such activities, but scientists have been trying to track species at highest risk of disappearing.
One organization, the International Union for Conservation of Nature (IUCN), has been assigning labels to species to assess extinction risk. But such lists, the researchers with this new effort note, only show which species are currently at risk of disappearing—they do not show the drop in population levels of species that are not currently at risk of going extinct. To learn more about such trends, the researchers analyzed available population data for more than 70,000 species around the world to see how their numbers have changed since recordkeeping first began.
They found that 48% of species have declining populations and just 3% have rising populations. They also found evidence showing that 33% of species currently classified as nonthreatened on the IUCN Red List are actually spiraling toward extinction.
