PHILADELPHIA (CBS) — Since the Democratic National Convention is in town, a Philadelphia museum is getting into the political spirit with a new exhibit focusing on an unusual aspect of past presidents: their hair.

The display at the Academy of Natural Sciences focuses on Thomas Jefferson who had a huge fossil collection, Ulysses S. Grant and Teddy Roosevelt who was a very strong conservationist who helped build the national parks system.

Jefferson’s fossil collection which shows his penchant for animal bones wouldn’t have been possible without the help of a famous explorer.

“He had sent William Clark of the famous Lewis and Clark expedition out to collect bones in Kentucky,” explained Bob Peck, a senior fellow at the Academy. “They weren’t quite sure what they were. People were using them as doorstops and paper weights and all kinds of things and Jefferson said no we must bring these back to Philadelphia.”

Some letters and books owned by the presidents are also on display which show the presidents’ love for animals and science and learning more about their country.

But perhaps the most interesting aspect of the exhibit is the collection of the presidents’ hair.

Peter Brown, an attorney and enthusiastic naturalist of the 1700s and 1800s studied their locks.

“This collection is unusual because it was collected not for political reasons or even sentimental reasons, it was collected for scientific reasons,” noted Peck. “Because Brown thought that if he could get hair from different people and study them under the microscope he might be able to understand better how people were related to each other.”

The collection is part of PoliticalFest and is on display through tomorrow.