SCIENCE
Teachers, scroll down for a quick list of key resources in our Teachers Toolkit.

Photograph by Pierre Fidenci, courtesy Wikimedia. CC-BY-SA-2.5
Discussion Ideas
- Why was the new research able to provide a more robust account of the populations of western lowland gorillas and central chimpanzees?
- The 13-year analysis, the largest gorilla and chimpanzee survey in history, allowed scientists to fill in the gaps between previously surveyed areas.
- The research spanned “59 sites in five countries surveyed between 2003 and 2013, totaling 61,000 person-days of fieldwork.”
- The survey included foot patrols, investigation of gorilla nests and habitat, and spatial modeling.
- The 13-year analysis, the largest gorilla and chimpanzee survey in history, allowed scientists to fill in the gaps between previously surveyed areas.
- The new survey estimates 361,900 gorillas and 128,700 chimpanzees in Western Equatorial Africa. Does this mean gorillas are no longer endangered?
- No! All species and subspecies of gorilla, including the western lowland gorilla, are critically endangered.
- Critically endangered species are among the most threatened of all endangered species: They face a 50% chance of extinction in the wild within 10 years or three generations. Use our downloadable graphic to better understand the categories and criteria of endangered species.
- No! All species and subspecies of gorilla, including the western lowland gorilla, are critically endangered.
- What factors put gorillas at risk?
- The authors title their paper “Guns, germs, and trees.” There’s your answer.
- guns. Although it is strictly “illegal to kill or capture any great ape in all the nations where they live … poaching to supply bushmeat to fast-growing cities is rife.”
- germs. “Outbreaks of Ebola virus have also decimated populations in recent decades, with ‘catastrophic’” outbreaks wiping out 90% of a gorilla community within six months.
- trees. Habitat destruction (deforestation resulting in felled trees) is probably the single leading threat to gorilla populations. The most predominant form of habitat destruction is agricultural development for palm oil plantations.
- The authors title their paper “Guns, germs, and trees.” There’s your answer.
- How can local and global communities contribute to gorilla conservation?
- Locally, the “most important single factor in determining the survival of gorillas was the presence of park guards to deter poachers.”
- Globally … we need to rethink our consumer choices and economic development strategies. There are no easy answers.
- How can we support smallholder farming without encouraging palm oil plantations? Learn more about smallholder farming here and the palm oil industry here.
- How can we support economic development in underdeveloped nations without putting their natural resources at risk?
DISCUSSION IDEAS
The Guardian: Gorillas are far more numerous than previously thought, survey reveals
Nat Geo: Analyzing the Distribution of Vegetation Zones and Mountain Gorillas in Virunga National Park
(extra credit!) Science Advances: Guns, germs, and trees determine density and distribution of gorillas and chimpanzees in Western Equatorial Africa