Ali loved a crowd, and often found one on 79th Street in Chicago, near the offices of Muhammad Speaks and the popular Tiger Lounge. (© Lowell K. Riley)

A Chicago author tackles the complex life of Muhammad Ali in a new biography with some fascinating revelations.

Neuron in tissue culture. (GerryShaw via Wikimedia Commons)

For more than 20 years, researchers at Northwestern University have collaborated with a global network of scientists to try and unravel the mysteries of Parkinson's disease. A study published this month in Nature Genetics shares an important discovery from that research.

Muhammad Ali versus Ernie Terrell at the Houston Astrodome in 1967. (Cliff / Flickr)

A Muslim prayer service was held Thursday to honor the boxer in his hometown of Louisville, Kentucky. As part of a Nation of Islam delegation, Salim Muwakkil met Muhammad Ali in Kingston, Jamaica in 1974.