The Philadelphia museum's collection of more than 20,000 objects is based on material assembled by Thomas Dent Mutter, a professor of surgery at Jefferson Medical College, who presented it to the College of Physicians of Philadelphia in 1858.
The Bunker twins were born in Thailand (then Siam) in 1811. Their condition was considered a bad omen, but King Rama II's order to have them executed was never carried out. After being "discovered" by a British merchant, Robert Hunter, the twins were exhibited in the US and England, before touring the world and then becoming farmers in North Carolina.
They would spend three days at a time in each of their two houses, with the "guest" brother submitting to his "host's" every whim. Married to the sisters Adelaide and Sarah Yates in 1843, they eventually fathered 21 children between them.
Other unusual items at the museum include the Bunkers' conjoined liver, a collection of skulls, a tumour removed from President Cleveland and 2,000 objects extracted from people's throats.
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