Blue whales are among the biggest creatures on the planet today. But a few million years ago, they were practically petite.
Scientists think they know why these whales gained so much weight.
Environmental changes likely altered the distribution of whales' food supplies in a way that rewarded gargantuan creatures, a new study found. That likely prompted blue whales to balloon ten-fold, from roughly 10 feet long to their present size of up to 100 feet.
Scientists traced the transformation of whale sizes back nearly 30 million years. They found that very large whales only appeared along several branches of the family tree some 2 million to 3 million years ago, according to a study published this week in Proceedings of the Royal Society B. Read more...