How Closely Is Animal Size Linked to Extinction Risk?

Scientists have concluded that a species’ physical size is one factor that can put it at risk of extinction.

Accordingly, they added that measures should be developed to protect animals at both extremes of the size spectrum.

Very large animals face a higher risk of extinction due to indiscriminate hunting, while very small animals may become extinct because of environmental pollution and logging.

A research team led by Professor Bill Ripple of Oregon State University said, “The largest vertebrates face the greatest threat from direct killing by humans, while the smallest species are more likely to have restricted geographic ranges—an important predictor of extinction risk. They are therefore endangered by habitat destruction.”

The BBC reported that the study provides evidence that the current scale of animal extinctions signals a sixth mass extinction, and said the findings could spur scientific efforts to identify the key factors driving animal extinction.

Research on birds and mammals has revealed a link between body size and extinction, demonstrating that animals with large bodies are more likely to become extinct.

Professor Ripple said, “Surprisingly, we found that not only the largest vertebrates face the highest risk of extinction, but very small animals are also at extremely high risk.”

Until now, conservation efforts have focused on protecting large animals such as elephants and lions.