ingridscience

The bodies of different animals look different as they are adapted for their particular environment and place in the food chain. This lesson looks at two different kinds of adaptation: where the eyes are on the head and what shape the teeth are.

Eyes activity

Teeth activity

Look at (an) animal(s) and discuss their features and needs
Start with discussion of how living things stay alive:
We are living, because we breathe, eat, reproduce (have babies). Every living thing needs to breathe (or get oxygen from the air), needs food for energy (different kinds) and water, and a place to live.
Show the tree of life poster:
All these living things need these same things to survive. What living things do you see? (And discuss how each one breathes, eats etc.)

Look at one or more of the following animals closely:

Hand out a wood bug in a dish to each student and ask them to use their magnifier to look at them closely.
Ask many legs does it have; can they see its eyes on the side of its head? Discuss how they get air from gills (like a fish) and other features that allow them to stay alive.
Return wood bugs to a habitat where they have food and water.
Look at wood bug images (projected large if possible) to see the gills and other features, and a wood bug with babies.

Not all animals have legs. Can you think of some?
Hand out a worm in a dish to each student.
There’s an animal on your desks that does not have legs.
Tell me what else you notice about it. How is it different from us? How is it the same? How is it different from a wood bug? How is it the same?
Discussion: if it has no legs - how does it move? Contract your muscles to make yourself move.
Worms only have primitive eyes, enough to sense light and dark. Cover yours to see like a worm.
Return worms to a habitat (e.g. worm compost bin) where they have food and water.

Tree of life
Find worms on the tree of life and/or find wood bugs (or where wood bugs would be - they're not on the poster).
These are animals without bones.
Look at all the other animals that do have bones.

Look at skulls of a prey and predator animal.

Using a number line to sort animals by number of legs
There are a huge variety of animals - show the tree of life poster. We can start to understand this variety by looking at one characteristic: legs on animals.
Lay out the number lines for students.
Hand out wood bugs, worms, and other animal images/point to other real animals in the room.
Look at the worms and wood bugs with a magnifier.
Ask students to put each animal or picture next to the number of legs it has. If you are not sure, don’t guess - look closely and you might have a better idea of the answer. Scientists often look closely to learn more about something.

Listen to an audio recording of a horse galloping and walking. These are sounds of an animal that moves with four legs.
Other animals with 4 legs can do this too - you may have seen dogs doing it.

Using a Venn diagram to sort animals by their features
Make overlapping circles with string, or draw them on a large piece of paper.
Hand out wood bugs, worms, and other animal images/point to other real animals in the room.
Ask students to sort the animals into the Venn diagram by whether they have legs or not, and whether they have bones or not.
Students should look closely at the living things with magnifiers to see if they have legs. Students will not be able to see if they have bones or not, but use discussion about how squishy the animals are to help them figure out if they have bones. Wood bugs do not have bones, but a hard shell (exoskeleton) to protect them.

Possibly add a third circle to the Venn diagram - whether the animals have eyes or not.

Discussion after Venn diagrams are complete:
Even though some animals have legs and some don’t they can all move. They move using their muscles. For the animals that have bones, the muscles work by pulling on the bones.
Look closely at each of the animals to see how they move with and without legs or bones.

Possible animals to include:
Wood bug: legs, no bones. Muscles lift legs up one at a time and push the ground.
Worm: no legs, no bones. Muscles contract and expand to make the worm stretch. Bristles.
Snake: no legs, bones. Muscles attached to the bones bend the body and grip the surface.
Person: muscles connect to the bones. When the muscles contract the leg lifts up.
Horse: legs and bones, like us, but they have 4 legs.

Several stations for students to rotate through:

Station 1:
Look at real hornets closely. Draw them.
Materials:
Wasps in petri dishes with magnifiers

Station 2:
Look at the outside of nests.
Peer into the complete one to see the cells inside.

Station 3:
Look at the outside of the nest with microscopes.
Materials:
6 microscopes, whole outside of nest, tape to put some nest in journal

Station 4:
Look at the inside of the nest. Draw how they built it.
Materials:
Nest inside, individual cells in magnifier boxes.

You tube video of nest building:
layers of nest being added over time: http://www.youtube.com/watch?v=cymGYvpKGOg&feature=related
time lapse of outside of nest being built: http://www.youtube.com/watch?v=JF25K9yg8oQ
half a hornet’s nest, see larvae being fed. http://www.youtube.com/watch?NR=1&v=v4h_DIQKPPI

Do each of the activities in turn, collecting and graphing class data in each case.

Lay out a selection of activities on separate tables - recommended group of four activities: What sticks to magnets?, Magnetic force through materials, Magnet pendulum and Magnetic force field patterns.

For guided experimentation, show students specifically what to do at each station and what they might find.

For free experimentation, The Play-Debref-Replay method of science teaching works great for this activity (see the resource). Explain to students that they will be freely exploring at each station, to find out about magnets. No ideas are wrong to try - just be safe and keep the materials at the station. Briefly introduce the students to each station: what materials are there; what themes they will be exploring (e.g. what materials are attracted to magnets at "Magnets: what sticks to them?").

Allow at least 8 minutes per station for students to explore with the materials independently - the teacher does not tell them what to do with the materials, but allows the students to explore independently. ("Play" period defined by Wasserman - see resource). Teacher can opt to have students move to a new station at designated times, or to move when they wish. Ideally, students write down what they discover at each station - they will refer to these notes when reporting back to the class, and for later experimentation; it also encourages good note-taking habits.

"Debrief" period: Regroup to hear what the students discovered. Write up students' discoveries while introducing them to the terminology of forces and magnets. Guide the conversation to allow students to conclude things about magnets.
e.g. Students might say that "Different materials "stick" to magnets; write up that magnets have a "force" that pulls things towards them and makes them stick. The materials are "attracted" to the magnet. Ask students about which materials were attracted to magnets, to have them distill out that metals are attracted, but only some metals (those with iron in them). (Some objects may have metal inside them, so confuse the issue, but students will often come up with ideas like this with time).
Other concepts to end up at: magnetic force can be a push or a pull, magnetic force can act at a distance, the force field around a magnet is of a varying shape depending on the magnet.

Optional: when students come up with further experiments to test their ideas, focus them on things to compare, how to reduce to only one variable so they can test a hypothesis etc. Then if time, allow students more time to try out their experiment ideas, and to explore further. ("Replay")