Animal size varies greatly across different species, from the tiny bumblebee bat, which weighs less than a penny, to the massive blue whale, the largest animal on Earth. Size can influence an animal's habitat, diet, and behavior. Larger animals often require more food and space, while smaller animals may adapt to living in tighter environments. The size of an animal is often measured in terms of weight and length. For example, African elephants can weigh up to 12,000 pounds and reach lengths of 24 feet, while house cats typically weigh between 5 to 20 pounds and measure about 18 inches long. Understanding animal size helps scientists study their ecology and conservation needs.