Up until about 100,000 years ago, sloths could be as tall as giraffes and beavers weighed as much as front row forwards. But that changed when homosapiens entered the picture, according to a 2018 study published in the journal Science. Due to rising global temperatures and overhunting of large mammals, the average animal size fell by an estimated 50 to 75 per cent. Experts predict that animals will continue to shrink if humans don’t adjust their behaviour. Worse, many large animals like whales and polar bears could go extinct altogether. Sydney’s world-famous Taroonga Zoo is a world leader in the fight against animal extinction. Learn about its history and conservation work.
13 things you never knew were shrinking
For better or worse, these things are getting smaller and smaller – and you probably haven’t even noticed.