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1 .<-NARRATOR:-> Listen to part of a lecture in a biology class.
1 .<-FEMALE PROFESSOR:-> Birds have some of the best vision capabilities in the animal kingdom.
2 .Some bird species have vision that is eight to ten times greater than humans!
3 .Overall, a bird's eyes are extremely important for its survival.
4 .One aspect of birds' eyes that plays a role in helping them survive-
5 .in other words, to find food or to avoid predators-
6 .is the position of the eyes in the skull.
1 .Some birds have eyes that face forward on the skull...
2 .kind of similar to how humans' eyes are positioned.
3 .Forward-facing eyes allow a bird to clearly see and judge distances...
4 .because it can focus on objects with both of its eyes
5 .and correctly perceive height, width, and depth.
6 .One type of bird with eyes positioned in the front of the skull is the hawk.
7 .Hawks eat animals like mice.
8 .Hawks have such good eyesight that they can spot a tiny mouse in a field from high up in the air.
9 .They spot the mouse and swoop down to catch it.
10 .Without such good eyesight, they would not be able to spot or catch their food.
1 .Other birds have eyes that are located on each side of the skull.
2 .This positioning of the eyes can help a bird to avoid predators.
3 .Instead of just seeing what's directly in front,
4 .they can see things that are on either side...
5 .permitting them to watch for danger in all directions.
6 .Imagine a duck wading near the edge of a lake.
7 .It needs to spend time eating grasses and insects,
8 .but it is also on constant lookout for danger from its predator-like the fox.
9 .An eye on each side of the duck's head allows it to see a fox approaching from either side.
10 .If it spots a fox, it can then fly away to safety.
11 .The placement of the eyes are critical in helping the duck avoid predators.