The largest lake ever to exist on Earth – the Paratethys megalake – suffered a 'disaster' that killed off most of its lifeforms less than 10 million years ago, a new study says. At its vastest, Paratethys had a surface area of more than a million square miles (2.8 million square km) – slightly larger than the present-day Mediterranean Sea, according to a team led by experts at Utrecht University, Netherlands. For a modern day comparison, Paratethys would stretch from the eastern Alps to what is now Kazakhstan in central Asia. It also contained a water volume of more than 1.77 million km3 – representing more than a third the volume of the Mediterranean today.