Biology 9700 · AS & A Level · Natural and artificial selection
Natural and artificial selection — practice question
All present-day dog breeds are members of one species and are believed to have arisen from 14 ancient breeds through artificial selection. The golden retriever is a modern breed that is often trained as a guide dog for people who are blind or visually impaired. Fig. 1.1 depicts a golden retriever.
(a)[4]
Explain how artificial selection could have been applied to produce golden retrievers with the characteristics needed for a guide dog.
(b)
(b(i))[2]
Suggest the type of isolating mechanism preventing:
• the three species of jackal interbreeding
• the dingo mating with all the other members of the genus Canis apart from the domestic dog.
(b(ii))[2]
Using the information in Fig. 1.2 and Table 1.1, state:
• one reason why the members of the genus Canis could be described as one species
• one reason why they should be described as separate species.
Worked solution & mark scheme
This 8-mark question has a full step-by-step worked solution and mark scheme. One marking point: “(desired characteristics) chosen by humans” …