Summary Look at how eyes are often placed on the front of the head for a predator and the sides for prey animals. Test your visual field and depth perception, and compare to animals. Science content Biology: Features, Adaptations of Living Things (K, 1, 3, 7) Biology: Sensing, Organ Systems (4, 5, 6) Biology: Evolution, Natural Selection (7) Lessons activity is in Animal adaptations - eyes and teeth Eyes Materials pictures (or a skull) of prey and predator animals and their eyes e.g. deer, cat, showing the eyes on the side and front of the head respectively Procedure Look at the animal skulls or pictures. Ask students to notice the location of the eyes - whether they are on the front of the head or on the sides of the head. Discuss how prey animals usually have eyes on the sides of their head, so that they are able to notice predators approaching from all directions. Predators often have eyes at the front of the head to enable better depth perception, which allows them to gauge more accurately how far away prey is, and to perceive prey that is trying to hide through camouflage. The different eye arrangements are an adaptation for each animal's environment. Optional: do activities to compare how eyes on the side of the head and the front of the head are useful: Visual field test for the advantage of eyes on the side of the head: Work with a partner to see how far behind us we can see: partner holds their finger behind your head, then slowly moves it around the side of your head. Tell them when you see the finger. Then switch over. We cannot see far to the side - our visual field is about 200 degrees. Herbivores are able to see much further to the side, with their eyes on the sides of their head - their visual field is 350 degrees. They can almost see behind their head. Stereo test for the advantage of eyes at the front of the head: Eyes at the front allow animals to see how far away something is - depth perception. Try putting your fingers to the side, then slowly bring together to meet in front of you. Now try with one eye closed. (see notes) For most of their visual field, animals with eyes at the sides of their head can only see with one eye. They may have binocular vision for a small part of their visual field, right in front of their face. Notes To try for visual field test: Partner walks to the side of the person, like a predator. Predator tries to sneak up on the prey. Give them a mirror to see behind like a horse? Stereo test did not work so well: kids got it to work pretty well with one eye closed. Also hard for them to close one eye - eye patches?! ?Change to a test where you say which object is in front when shown two at a distance - they all stand in a line and raise a hand depending on which object is in front. Grades taught Gr K Gr 1 Gr 2
