Humans are a common species in the Shrek universe. Most of them are identical to human stereotypes in the "real" universe. Their lands are ruled by Monarchs (Kings and Queens). These monarchies are divided into fiefs, such as Du Loc which was ruled by Lord Farquaad. They are very unnaccepting of other races, especially ogres and generally believe themselves above fairy tale creatures.
Humans life span is approximatley 80 years long. A human will generally become mature at the age of around 20 years old. Humans mate for life with two genders marrying and living together. Humans are mammals and therefore sexually reproduce.
Humans are quite violent by nature and therefore each kingdom and fief holds a standing army in case of war. Human armies are divided into two groups, Knights and peasant soldiers. Knights are held in higher regard than peasants and will often lead their lessers into battle. Knights can also win the honour of carrying out quests for either themselves or their respective lord.
Retrieved from WikiShrek (shrek.wikia.com), the wiki all about Shrek.