Natural and artificial selection — practice question

The European hedgehog, Erinaceus europaeus, is a small mammal that eats both plant and animal matter. Its body is covered with spines, which are usually brown. A rare variant, which does not have the brown pigment, has blonde (pale yellow) spines. This characteristic is controlled by a recessive allele. Fig. 1.1 shows a European hedgehog with blonde spines. Alderney is a small island between the UK and France. Hedgehogs were absent from Alderney until the 1960s, when three pairs of hedgehogs were brought onto the island. The hedgehogs began to breed and some of the offspring had blonde spines. By 2017, the hedgehog population, including individuals with brown spines and individuals with blonde spines, had risen to approximately 600.