In the 1930s in China's Sichuan province a mysterious bone disease struck a number of villages, leaving a group of people standing less than a meter tall. No one knows what caused the disease, which appears to have existed for around only 10 years, and it has never been found to have occurred again outside of the region after that time.
As Reuters reports, the group of people who contracted the disease as children have mostly died, making it unlikely that the mystery will ever be solved.
As one victim tells Reuters, "We don't know what caused it. We don't know if there is something wrong with the water, or the shape of the mountains, or the depth of the valley, or the humidity. We just don't know what went wrong and nobody else does."