How much land on Earth is inhabited?

Question: How much of the land on Earth is covered by humans?

Answer: Approximately 10%.

This question is an interesting one because, when my friend asked me the other day, I could tell her confidently that not only did science know the answer, science had multiple different ways to quantify that answer, but that I had absolutely no idea what it was.

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The costs of a big brain outweigh the benefits

Brains rather than braun may have guided our ancestors out of Africa, but new research suggests primates’ big brains are no longer the assets they once were.

A study published in the journal Evolution reports that larger brains are directly related to an increased risk of extinction in modern primates. Researchers led by Alejandro Gonzalez-Voyer at Doñana Biological Station in Spain, compared published data on 474 species of mammal, with their IUCN Redlist categorisations, to find out how different biological traits influence extinction risk. The team found that larger brains tend to be associated with a longer gestation period, longer weaning period and smaller litter sizes, all of which indirectly increase extinction risk.

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