There are several reasons that the precise number is difficult to determine.
Additionally, the IUCN has only assessed the extinction risk of about 5% of the known species.
This inevitably raises the number of animals that may have gone extinct without anyone noticing.
Brown Spider Monkey. (Photo: wollertz/Depositphotos)
The fact that many undiscovered species likely live in tropical, understudied areas makes quantification harder for academics.
The number surprised the study’s lead author.
I thought, jeez, have I made some mistakes in the calculations?
Digital rendering of a herd of woolly mammoths. (Photo: auntspray/Depositphotos)
How did the researchers calculate the extinction rate?
However, after looking at other wildlife groups like amphibians and birds, the numbers varied wildly.
Eventually, they noted a sweet spot.
Scimitar-horned oryx. (Photo: rixipix/Depositphotos)
They tend to cluster around about 100 [E/MSY], Cowie said.
I think that’s a more reasonable, not overly conservative, but not overly exaggerated value.
We should be supercautious about trying to nail a number down based on the existing literature, Alroy says.
Axolotl. (Photo: Argument/Depositphotos)
My feeling is that we don’t have a very good fix on the current extinction rate whatsoever.
How many animal species have humans driven to extinction?
Digital rendering of a herd of woolly mammoths.
