The Somali ostrich, Struthio molybdophanes, is listed as “vulnerable” by IUCN.WIKIMEDIA, DONNA BROWNSpecies within the “Goldilocks zone”—neither too big nor too small—have the lowest risk of extinction, while very large and very small animals are at greatest risk, according to a study published yesterday (September 18) in PNAS.
“Surprisingly, we found that not only the largest of all vertebrate animal species are most threatened, but the very tiniest ones are also highly threatened with extinction,” lead author Bill Ripple, of Oregon State University, tells BBC News.
“Knowing how animal body size correlates with the likelihood of a species being threatened provides us with a tool to assess extinction risk for the many species we know very little about,” Ripple says in a release.
Ripple and his team created a database to examine the correlations between body mass, range size, and extinction risk for more than 27,000 vertebrates on the International Union for the Conservation of Nature (IUCN) Red List of Threatened Species, according to the release.
The researchers found that hunting, trapping, and ...
