Animal SortAnimals Without

BackbonesLesson 57

In our last lesson we learned which animals have backbones. We also learned ways to sort animals with backbones. We learned we can

sort them into five groups: amphibians, reptiles, mammals,

birds and fish.

Today we will learn about the many animals which do not have

backbones.

There are more animals without backbones than with backbones.

Some animals without backbones have shells or hard body coverings.

This helps them stay safe.

Some animals without backbones have no shells. They have soft

bodies. These animals must use other ways to stay safe.

Let’s make a list of animals without backbones who have

hard outer shells.

Snails have no backbones and they carry a hard shell around on their back for protection. The shell

is the snail’s home.

Snails move along on one wide, slimy foot. To hide from enemies the snail can pull its body into the

shell. Snail’s eat plants.

Here is a video of a snail walking.

• https://www.youtube.com/watch?v=8crNeMGd_l4

Spiders do not have

backbones but have a

hard covering on their body.

Spiders have 8 legs.

Spiders make webs to catch their food. Spiders are meat eaters.

They eat insects.

Here is a video of a spider spinning its web.

• https://www.youtube.com/watch?v=g5iN0ZaoW7M

Lobsters do not have backbones but have hard shells. Lobsters are meat

eaters. They live in the ocean. Lobsters eat fish, crabs and clams.

Here is a glimpse of a lobster underwater.

• https://www.youtube.com/watch?v=Lj0ecgBvSwo

Let’s make a list of animals without backbones who have no

hard outer shells.

Jellyfish do not have backbones and do not have a hard

outer shell to protect themselves. Instead

they can sting enemies with their

tentacles.

Jellyfish eat fish and live in water. Here is a video of a jelly fish

swimming.

https://www.youtube.com/watch?v=GTXinF8ZVCo

Centipedes do not have backbones but do have a hard outer shell. Centipedes have

around 30 legs.

Centipedes are plant eaters and meat eaters. They eat insects and

spiders.

Here is a video of a centipede eating a spider.

• https://www.youtube.com/watch?v=BMwHqNWFOZk

Earthworms have no backbones and have no hard outer shells to

protect themselves. Earth worms also do not have legs.

Earthworms eat plants and plant materials in the soil. Earthworms

help soil.

This video shows how earthworms move.

• https://www.youtube.com/watch?v=_mba2COlUOg

Today we learned about a few living things that do not have

backbones. Some of the living things have hard outer shells and

some do not.

In our next lesson we will review what we have learned in Unit 5

Animals and Plants are Living Things.

Keep observing the world around you!