Owls
How are owls different than other birds? (awake at night, vomit undigestible prey parts).
Birds of prey are birds that hunt. How can you tell that owls are birds of prey? (eyes face forward, binocular vision. Use the large eyeballs to demonstrate binocular vs. monocular vision).
How are they different from other birds of prey? Owls are nocturnal predators. What does that mean? (they hunt at night). Do owls and other birds of prey compete for food?
Eyes:
How are owl eyes different than other bird eyes? Why? Owl eyes are so large that they cannot move them in their sockets (Use the cups to demonstrate what it feels like not to be able to move your eyes).
Owl eyes are 1-5% of their body weight. If owls were as big as people, their eyes would be the size of softballs. Why are owl eyes so large? Larger eyes can take in more light at night.
How do owls compensate for not being able to move their eyes? Owls can turn their heads 270° in each direction.
Ears:
Do owls need to hear well to hunt at night? Why? How could the round face of the owl help it hear better? The face is shaped like a dish that funnels sound to the ears.
The owl's right ear opening is higher on its head, and the left ear opening is lower. This allows the owl to tell where a sound is coming from and how loud it is because it reaches the ears at different times (this is like binocular vision for the owl's ears).
The location of the sound will activate special cells in the owl's brain. Each cell represents a point in space around the owl. The owl can make a "neural map," or a sculpture of the sound in its brain. The owl can use this "map" to know the exact location of its prey. Owls have been known to catch prey in pitch black rooms using only the sound of their prey.
Wings:
Do owls make sound as they swoop to catch their prey? Why else might owls be adapted to fly quietly? Fewer organisms are awake at night so there is less sound everywhere. Silence is a type of camouflage.
How are owls quieter than other birds? Owl feathers have a fringe on them that helps muffle the sound. Use the rulers to demonstrate how fringe muffles sound. Swing the fringeless ruler around fast enough to get a really good sound out of it. Then try to get a sound with the fringed ruler.
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