Animals —complex, multicellular organisms equipped with nervous systems and the ability to pursue or capture their food—can be divided into six broad categories. Here are the six main animal groups, ranging from the simplest (the spineless invertebrates) to the most complex (mammals, which can adapt to a wide range of habitats).
Fiji’s Extinct Megafauna
Strauss, Bob. “6 Basic Animal Classes.” ThoughtCo, Aug. 27, 2020, thoughtco.com/the-six-basic-animal-groups-4096604.