Kittens have distinct physical traits that set them apart from adult cats. They are small and lightweight, usually weighing only a few ounces at birth. Their fur is soft and fluffy, with colors and patterns that vary by breed. Kittens are born with blue eyes that may change color over time. They have relatively large, pointy ears, temporary baby teeth that emerge around 2–4 weeks, soft padded paws with retractable claws, and long, flexible tails used for balance and communication.