1. 
   Symplesiomorphy
   Symplesiomorphy meaning shared old form) is the persistence of ancestral (primitive) traits in different clades .
   Found op http://www.enchantedlearning.com/subjects/dinosaurs/glossary/
   
   
2. 
   Symplesiomorphy
   In cladistics, a symplesiomorphy or symplesiomorphic character is an ancestral trait shared by two or more taxa. A plesiomorphy refers to the ancestral trait on its own, usually in reference to another, more derived trait. A symplesiomorphic trait is also shared with other taxa that have an earlier...
   Found op http://en.wikipedia.org/wiki/Symplesiomorphy
   
   

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