A critical review of ‘Speciation or irruption: the significance of the Darwin finches’

Senior undergraduate zoology students critically reviewed Harper's (1980) ‘Speciation or irruption: the significance of the Darwin finches’. A summary of their findings is used to evaluate Harper's proposal that presentation of radical alternative theories is a valuable means of encouraging the creative and critical faculties of undergraduate science students. Harper's (1980) hypothesis is shown to be a completely inadequate explanation of the distribution of the Geospizinae on the Galapagos Islands. More importantly, Harper's (1980) method of supporting his hypothesis violates some fundamental criteria of science. Harper (1980) was successful in eliciting critical thinking in students reviewing his work, but his alternative hypothesis to speciation is rejected without having to examine speciation itself. We conclude that although implementation of Harper's general proposal may stimulate critical thinking by students, the specific approach of using radical alternatives may be misleading at some academic levels. Therefore, if this method is used, examples of alternative hypotheses should be chosen with great care.