What contributions did Aristotle make during the Hellenistic era?

Aristotle is remembered for his contributions to the field of philosophy and science during the Hellenistic era.

One of the biggest contributions made by Aristotle was the way in which he researched an issue. His advice to study books/research done on topics, to perform independent studies, and to gain a sense of the general consensus on a topic are the foundation of what would later become the scientific method.