Three reasons why dichotomous keys would be subject to changes over time

The dichotomous key refers to a tool that determines the unfamiliar organism by comparing its features with the arranged set of mutually exclusive features of distinct species. The dichotomous keys modify with time due to the following reasons:  

1. The keys are framed on the basis of the features of the previously known organisms. If one finds novel features in the newly invented organisms, the keys get modify.  

2. The organisms can modify their features because of evolution.  

3. The dichotomous keys are totally dependent upon history. The scientists may not witness the present evolutionary variations taking place. This signifies that this characteristic will be determined later in the coming time, therefore, the keys modify.  

the father in the first generation probably had the recessive colorblind trait in his x chromosome. if he and his wife both had the colorblind trait, even if she had 1 recessive and 1 dominant, then that trait would be passed on to their kids.

(since you didn't attach the family tree this is just an assumption)

b. to discover aspects of the natural world.

hopefully i .