Classifying Animals Background Information for Teachers, Parents and Caregivers
This page provides information to support educators and families in teaching K-3 students about classifying animals. It is designed to complement the Classifying Animals topic page on BrainPOP Jr.
Billions of living things call our planet home, and scientists classify them into different groups to help them organize and understand how living things are related. This movie introduces the concept of animal classification by showing how scientists separate animals into two main groups, vertebrates and invertebrates. These categories are further classified into more groups, or sub-sections, such as insects, fish, birds, reptiles, amphibians, and mammals. Each group of animals has specific adaptations and similarities. We recommend pausing throughout the movie and give children opportunity to come up with animals that fit in the category being discussed. Be sure that children describe the animal and explain any special adaptations.
Remind your children that when scientists classify things, they sort them into groups to show how they are alike, which also highlights important differences. At the most basic level, all animals are divided into vertebrates and invertebrates. A vertebrate is an animal that has a spine, or backbone. People are vertebrates. Have your children feel how their spines go up their back and through their necks. Dogs, cats, birds, fish, snakes, and frogs are all vertebrates. Invertebrates are animals that do not have backbones, such as insects like butterflies and grasshoppers, spiders, and worms. Most of the animals on Earth are actually invertebrates. Many children believe that spiders are insects, but they are actually arachnids. Scientists classify insects as animals with three main body parts, and spiders have two. Scorpions and ticks are other examples of arachnids.
Vertebrates might all have a back-bone, but children should know they are not at all similar! Mammals are vertebrates that breathe with lungs and get milk from their mothers when they are young. Most mammals bear live young that need care from a parent, but monotremes such as the platypus and echidna are mammals that lay eggs. Monotremes are considered the most primitive order of mammals. However, they still provide milk for their young. Dolphins, porpoises, and whales are mammals that live in the ocean and have lungs, so they must come up for oxygen. All mammals have hair or fur. Even whales have tiny hairs.
Birds are vertebrates that have lungs, two wings, two legs, and a beak. Birds are the only animals that have feathers. Not all birds fly; penguins and kiwis both have wings but they are flightless birds that have adapted to their environments.
Fish are vertebrates that live underwater and breathe through gills, which take oxygen out of the water. Most fish have scales that cover their bodies and help them move through the water. It is important for your children to understand that not all living things underwater are fish. Coral and anemone are not fish, nor are clams and crabs. Sharks and rays are fish that have bodies made out of cartilage and do not have scales.
Amphibians are vertebrates that live on land and in water. Many amphibians go through metamorphosis; they begin life in the water and have gills. Later they develop lungs and are able to move to land. Frogs, salamanders, newts, and toads are all types of amphibians, and children who want to know more about amphibians would enjoy our movie on Frogs. Amphibians are cold-blooded and rely on the environment to help control their body temperatures. They may use a sunny spot to warm up and use water or shade to cool down. Insects, most fish, and most reptiles are cold-blooded.
Reptiles are vertebrates that have lungs and their bodies are covered by scales. Most reptiles lay eggs, similar to birds. Many reptiles do not look after their offspring. Unlike mammal’s offspring, young reptiles are equipped to survive without parental care. Snakes, lizards, crocodiles, and tortoises are all reptiles. Sea turtles are also reptiles that have adapted to live in water.
There are many, many more invertebrates than vertebrates: 98% of the creatures on Earth are invertebrates As mentioned before, clams, crabs, and coral are invertebrates, as well as arachnids, butterflies, mollusks, protozoa, starfish, and sand-dollars. Invertebrates, like amphibians, tend to be cold-blooded and rely on their surroundings to help them regulate their body temperatures. Most invertebrates live in water or moist atmospheres, though some insects inhabit dry land and have developed water-proofed shells. Invertebrates vary just as much as vertebrates do—just think of all the differences between a squid and a spider!
Scientists use classification to help them understand the relationship between living things, and to understand the similarities between many of the thousands of living creatures on this planet. Encourage your children to learn about different animals and help them classify them into different groups. How are they alike? How are they different? We recommend plenty of trips to the zoo or researching on the Internet to explore the animal kingdom. We also recommend watching the Rainforest movie together to see what types of animals you can find.