Cosima Niehaus is a fictional character from the television series Orphan Black. She is portrayed by actress Tatiana Maslany and is known for her intelligence and strong personality. Cosima is a graduate student studying biology and is particularly interested in genetics and cloning, which ties into the show's central themes of identity and scientific ethics. In the series, Cosima discovers that she is one of several clones, all created from the same DNA. Throughout the show, she works to uncover the truth about her origins and the organization behind the cloning project. Her character is notable for her advocacy for the rights of clones and her quest for knowledge.