(Image via Harvard Magazine)
The Mystery of Whales
The evolution of whales is fascinating. What was once heralded by creationists as the best evidence against evolution has become, in a span of only 30 years, one of the most convincing proofs of Darwinian evolution.
It began in the 1800s, with the discovery of a fossilized Basilosaurus. It was unquestionably a mammal, but it also shared features of marine reptiles. Only one creature’s bones matched its inner ear: whales. Yet the Basilosaurus also had legs, and even knees and toes. This prompted a thought experiment by Charles Darwin in On the Origin of Species. He posited that black bears, often seen by explorers swimming with its mouth wide open to catch insects, could have adapted through natural selection until eventually becoming a whale. He was widely ridiculed by creationists, who argued that mammals that adapted to aquatic life would be incapable of surviving, and the mystery stood for over a century.
It would be the 1970s before progress was made, when Philip Gingerich unwittingly took up the case — he was researching the rise of mammals at the beginning of the Eocene epoch and found pelvic bones jokingly attributed to “walking whales” in what turned out to be dry riverbeds. Further research led by Gingerich and other paleontologists over the next 30 years helped scientists fill in the full, surprising evolutionary story of whales. In the end, Darwin wasn’t far off.
- Another evolutionary mystery surrounding whales is how fin whales, which eat by swallowing up to 160% of their body weight in water and filtering krill and small invertebrates out of it, got so big. Turns out it has a lot to do with parachutes.
- Tall tales abound — from the days of the Bible — of men being swallowed whole by whales and surviving, but is it even possible?
- Oh, and whale poop is great for the ocean.