Comparative endocrinology is a fancy way of saying that scientists study how different animals have different hormones and how those hormones affect their bodies.
Hormones are like tiny messengers that tell different parts of our body what to do. Think of them like text messages that your brain sends to your body to help it work properly. The same hormone can tell one part of an animal's body to do one thing and tell another part of the body to do something different.
Scientists who study comparative endocrinology want to know how hormones help different animals do things like grow, mate, and hunt for food. They also want to know how different animals have evolved to have different hormones that work best for their bodies and environments.
For example, animals that need to swim in cold water, like penguins, have hormones that help keep them warm. Other animals might have hormones that help them see in the dark or jump really high.
Comparative endocrinology helps us understand how different animals work and how we can better take care of them.