Darwin studied actual birds on the Galapagos Islands instead of using a simulation, as you did in this lab. Studying natural selection in the field can be challenging. List at least three possible challenges Darwin might have faced.

1. Darwin did not know how genetic material passed from one generation to the next because Mendel's laws of heredity had not yet been formulated

2. Finches have many phenotypic adaptations that can not be observed easily  

3. Phenotypic traits are expected to evolve slowly, thereby taking many generations  

Explanation:

In the Galapagos Islands, Darwin observed that there were many varieties of finches that showed variation in the size and shape of their beaks. Darwin determined that finches' beaks evolved in response to environmental changes (finches' beaks were different in different islands). Darwin had several challenges to make this discovery. First, Mendel's laws of heredity had not yet been formulated, thereby difficulting the analysis of quantitative traits (in this case, finches' beak) which are the result of the combined action of many genes and the environment. Second, finches (as well as all species) possess many phenotypic adaptations, thereby difficulting the study of single traits in an evolutionary context. Finally, phenotypic changes are gradual and therefore descendence with modification cannot be easily recognized by observation in the field.

links? do you have a link? i don't see anything?