Coat color in cats is a codominant trait and is also located on the X chromosome. Cats can be black, orange or calico. A calico cat has black and orange splotches. In order to be calico. the cat must have an allele for the black color and an allele for the orange color. Use a punnett square to show why there are no male calico cats.

The males can only either be black or orange

Explanation:

There can be no male calico because for an offspring to be a calico the two codominant alleles must each be carried on the two X chromosomes and in the males, there is the presence of just one X chromosomes, thus they can either be black or be orange. For the females, the can only be black if they carry the black allele on both X chromosomes, the same goes for the orange.

Parents XB Y

XB XBXB XBY

XC XCXB XCY

XBY - black male

XCY - orange male