1. The sight of a chick with an open mouth reliably results in an adult bird providing food. The chick’s open mouth is an example of a(n) ……………………………. . 2. Evolution is the product of……………………………. and...

1. The sight of a chick with an open mouth reliably results in an adult bird providing food. The chick’s open mouth is an example of a(n) ……………………………. .

2. Evolution is the product of……………………………. and ……………………………..