Teeth show why giant apes died
Two million years ago in Southeast Asia, apes called Gigantopithecus blacki roamed the Earth. Researchers call the species “Giganto”, and believe it was three metres tall and weighed up to 300 kilograms – making it the world’s largest known primate (a group of animals including apes, monkeys and humans). For a long time scientists have wondered why they went extinct, but new research has revealed that Gigantos just couldn’t adapt to a changing world.
The first step was to work out when Gigantos died out. Researchers looked at fossils, such as teeth and pieces of jawbone, found in caves in southern China. Tests showed that the species died out some time between 295,000 and 215,000 years ago.
To find out more about where Gigantos lived, the team studied other samples from the caves, including fossils of different animals and ancient plant pollen. The clues they found showed that between 700,000 and 600,000 years ago, the local climate began to change. Over many years, lush forests became much drier and the fruit trees that had provided nearly all of Giganto’s food gradually disappeared.
The researchers looked at patterns on Giganto teeth and compared them to the teeth of Chinese orangutans, a species that survived far longer than Giganto. The teeth showed that when there was no fruit, the orangutans started eating leaves and flowers. By contrast, the Giganto teeth were worn away by tough, chewy foods. The team think Gigantos were too big to climb the trees for soft leaves and flowers. Instead, they had to eat dry bark and twigs from the ground, which were hard to chew and not nutritious. Slowly, Giganto populations fell until they died out. Scientists say this work will help them learn more about how primates cope with changing climates. Kira Westaway, who worked on the study, said it’s important to understand why species go extinct.