In order for evolution to occur, there must be A. Oa change in the temperature of the environment
B. change in migration patterns within a population
C. variation inthe gene pool of a population
D. a catastrophic event that occurs in the ecosystem

Color blindedness is a sex-linked trait. if we could see the pedigree chart for several more generations of the family illustrated here, we would expect a) more males to be color blind. eliminate b) more females to be color blind. c) no females to ever be color blind. d) an equal number of males and females that are color blind.