There is a great diversity of living
organisms on this Earth. There are natural groupings of organisms as they live
together. Humans however have developed ways to connect similar organisms that
do not live near each other. For instance, there are two places where
elephants live, India and Africa. They are both considered elephants because
they have similar characteristics, but they do not live together.
Humans have constructed a "Tree of
Life" to try and develop a pattern of similar characteristics and group
them into Kingdoms (very large groups), Phylums (large groups), Families
(smaller groups) and then genus and species, which identifies organisms that
can reproduce amongst themselves. Presently there are 6 kingdoms. Believe it
or not, we do not understand all organisms yet, so even the kingdom level can
change. In ancient Greek there was only two Kingdoms, Plant and Animal.
Children will learn about the kingdoms in later grades, but the kingdom they
are most familiar with is the "Kingdom Animalia."
Introduce the term "animal" as
being an organism that grows, has babies, and eats to grow and to nourish the
body. Animals can move or remain in one place; they may have a backbone (point
to your backbone) or may not have a backbone (i.e., snails, worms). Animals
are divided into animals with backbones called vertebrates and animals without
backbones called invertebrates.
Animals are divided into two major groups,
vertebrates and invertebrates. Children are usually familiar with vertebrates
including mammals, fish, birds, reptiles, and amphibians, but sometimes donít
realize that insects and snails also belong to the Animalia Kingdom.
Ask students to divide the animals
that they are familiar with. Ask them to think about dividing them into
animals with backbones and those without backbones. You may have to emphasize
that just having a skeleton is not enough to have a backbone. If you have a
backbone from a recent chicken dinner, bring it so they can see what backbones
consist of. You also may want everyone to touch their own backbone. The reason
for a backbone is to help large animals to move.
Develop the following type of diagram on
the board to illustrate the difference. Have students give examples. You may
have to help them with the first few examples.