What is one important way how do scientists group animals?

One important way scientists group animals is by their evolutionary relationships. This is called phylogeny.

Scientists use evidence like:

* Fossil records: Comparing the bones and skeletons of extinct animals to living ones.

* DNA analysis: Comparing the genetic makeup of different species.

* Physical characteristics: Analyzing similarities and differences in body structure, organs, and developmental stages.

This information helps scientists create a tree of life, showing how different species are related and have evolved over time. This is a crucial tool for understanding biodiversity and how organisms have changed throughout Earth's history.