Lucy was found by Donald Johanson and Tom Gray on November 24, 1974, at the site of Hadar in Ethiopia. They had taken a Land Rover out that day to map in another locality. After a long, hot morning of mapping and surveying for fossils, they decided to head back to the vehicle.
Alkanes are an example of saturated compounds. An unsaturated compound is a chemical compound that contains carbon-carbon double bonds or triple bonds, such as those found in alkenes or alkynes, respectively. Saturated and unsaturated compounds need not consist only of a carbon atom chain.
Unsaturated hydrocarbons are hydrocarbons that have double or triple covalent bonds between adjacent carbon atoms. Those with at least one carbon to carbon double bond are called alkenes and those with at least one carbon to carbon triple bond are called alkynes.