Meet Basilosaurus, an Ancient Whale
Want to come explore the deep history of whales? Whales are actually related to ancient land animals who went back into the sea – probably to escape vicious predators or to look for new food sources.
In the Sant Ocean Hall, you will have a chance to meet several ocean-going precursors to and relatives of modern whales, including the mighty Basilosaurus. Originally given this name – which means “king lizard” – because it was mistaken for a giant sea serpent, Basilosaurus was a creature more than 55 feet (16 meters) long. Follow along as this historic specimen is moved, restored, and remounted for the ocean hall.
- Sketch of a Basilosaurus skeleton. Image courtesy: Smithsonian Institution, National Museum of Natural History
A Fossil's Story
- Basilosaurus from Life in the Ancient Seas Exhibit. Image courtesy: Smithsonian Institution, National Museum of Natural History
Basilosaurus was one of the first named fossil whales in the world. It represents a sidebar in whale evolution. Because it has strangely long trunk vertebrae not found in any other whales, scientists believe it was an evolutionary dead end and thus it is a fascinating story about the twists and turns evolution takes over time.
This Basilosaurus' bones were originally collected in 1894 and 1896 in Alabama. Not a single individual, our Basilosaurus is a composite of the best-preserved bones from three different individuals. It was first displayed at the Atlanta Exposition in 1895. The current mount was completed in 1912 and has lived at the Smithsonian ever since, though not always in the same place. It was on display in the Smithsonian's Arts and Industries Building, the National Museum of Natural History's dinosaur hall and the fossil mammal hall. It was modified in 1989 when it moved into Life in the Ancient Seas. Now it is being prepared for yet another new home – the ocean hall.
How to Move a Basilosaurus
- Moving the Basilosaurus. Image courtesy: Smithsonian Institution, National Museum of Natural History
Moving a specimen of this size is no easy feat. First, many specimens around the Basilosaurus had to be removed just to reach it. Workers had to be careful of the fake seafloor underneath the mounts, since it was constructed simply of chicken wire and paper maché. They wanted to avoid falling through!
Using a lift, each vertebra was removed one at a time and labeled. Workers examined each bone and wrote a condition report. They bagged and labeled loose pieces and placed them into storage. They also removed the skull and lower jaw from their brackets and ribs and fragile vertebrae from the rib-bearing central column. What was left – a section of the rib-bearing column weighing more than 300 pounds – was moved as a unit. This piece was re-bracketed into a temporary base where it waited until it was ready for remounting.
Getting a Face Lift
To prepare the specimen for its new home, Basilosaurus was repaired, consolidated, and remounted. Most of this work was done by the specialist Canadian company, Research Casting International. During repair, workers used archival adhesives to fix any breaks in the bones. Then they treated the bones with a “consolidant” called polyvinyl butyral, a type of plastic resin dissolved in acetone. They painted this compound on the bones' surfaces, where it strengthened them by penetrating deep into the tiny cracks and pores.
To remount the specimen, workers padded the armature with urethane tubing or felt cloth so the fragile bones rested against padding rather than hard steel. This will insulate them from damage by vibrations. They also reconfigured the armature into a new posture to fit into its allotted space. Altogether, this work took approximately five people a period of about six months.
Special thanks to Steve Jabo, Dave Bohaska, Mark Uhen, Peter Kroehler and Dan Chaney for assistance with this story.
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