Final answer:
Our teeth are our most obvious physical adaptation for chewing hard objects. Different types of teeth in our mouth are specialized for different functions, such as cutting, tearing, and grinding food. Chewing, or mechanical digestion, is an important step in breaking down food for digestion.
Step-by-step explanation:
Our most obvious physical adaptation for chewing hard objects is our teeth. Humans have different types of teeth that are specialized for different functions. The sharp incisors at the front of our mouth cut and tear food, while the broad molars at the back grind food into smaller pieces when we chew. This process of mechanical digestion is an important step in breaking down food for digestion.