America's longest-serving prisoner in solitary has conviction quashed. Albert Woodfox, right, and Herman Wallace in Angola prison, in Louisiana. Woodfoxâs 1972 murder conviction was overturned when a US appeals court ruled his conviction was secured through racially discriminatory means.
Next, the Olmec created a complex drainage system. These inventions helped the Olmec survive. In addition to their inventions, they also understood many things in life, such as the concept of zero ,linear time, and gravity.
(See this possible timeline including the Olmec and Aztec civilizations) The Olmec civilization is believed to have been centred around the southern Gulf Coast of Mexico area (today the states of Veracruz and Tabasco) - further south east than the heart of the Aztec empire.