TOKYO: The life on earth started around 3.6 billion years ago. It was a time when all organisms were very small in size. It took a lot of years to grow with the passage of time.
Since then, things have accelerated a bit and – along with the great diversification of body forms – animals have tended to get bigger. Indeed, the largest animal ever to live, the blue whale, is still very much with us, and has been swimming the world’s oceans for only a couple of million years – a mere blink of the eye in the long, long history of life in the sea.
This trend towards larger body sizes through evolutionary time has become known as Cope’s Rule, after the American palaeontologist Edward Drinker Cope. Cope’s rule has been documented or disputed in hundreds of studies of numerous animal lineages over the last century, but a new study in the journal Science provides perhaps the most comprehensive test yet of its existence.
