25-million-year-old fossil solves mystery of whale evolution
THIS 25 million-year-old fossil answers questions about why whales are the biggest creatures in the world and shows just how much the majestic creatures have evolved over time.
The fossil, named Alfred, was part of the baleen whale family, including the humpback and blue whales — the biggest creatures on the planet.
You might not know it, but those whales used to have teeth and Alfred has shown palaeontologists how they came to be without them.
Alfred was a whale only about three metres long, a lot smaller than baleen whales today, which can measure up to eight metres.
Alfred also had teeth, something that hasn’t been seen in whales for a number of years.
Back in the day, whales would use their teeth to capture prey one-by-one, but Alfred is proof whales found a way to get more prey into their mouths at a time, meaning as the years went on, there became less of a need for teeth.
Museums Victoria and Monash University palaeontologist Felix Marx told news.com.au whales like Alfred started suctioning food rather than biting it.
There are horizontal scratches on Alfred’s teeth, which are usually only evident in animals who suction feed by moving their tongue back and forth.
“Rather than biting, he sucked prey like we suck a milkshake through a straw,” Dr Marx said.
Since whales began suctioning, instead of developing teeth, humpback and blue whales instead grew baleen, a comb-like bony filter system in their mouths.
Dr Marx said baleen allowed whales to suck in large amounts of prey and expel water from their mouths without losing their food.
“Alfred shows how ancient baleen whales made the evolutionary switch from biting prey with teeth to filtering using baleen. They first became suction feeders. Feeding in this way resulted in reduced need for teeth, so over time their teeth were lost before baleen appeared,” Dr Marx said
Whales who suction feed can catch a lot more prey than those mammals who eat with their teeth, and Dr Marx said this change in their eating pattern had something to do with why baleen whales were so much larger now than they used to be.
The fossil was found on the west coast of the United States and donated to Museums Victoria, where it was unveiled on Wednesday. The team of palaeontologists looking at Alfred will work to uncover the rest of the skeleton, which will provide more insights into how baleen whales began.
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Originally published as Fossil solves evolution mystery