In a particular zoo the population of spider monkeys has a higher proportion of individuals with light golden brown fur than spider monkeys in the wild. if the monkeys were recently captured from the wild and if fur color is largely determined by genetics, what evolutionary process is at work?

The evolutionary process is: microevolution

Microevolution is the occurrence of small-scale evolutionary changes, in this case a change in gene frequencies within a population. They occur on a short time (the monkeys were recently captured). Plus, another indication that this an example of microevolution is that the change occurs below the species level, since the difference in the fur.