AQA Biology Paper 3 2020

A-level BIOLOGY Paper 3 S - The Marketplace for Revision Notes & Study Guides Downloaded by: jessicaonyebuchi | Distribution of this document is illegal S - The Marketplace for Revision Notes & Study Guides 2 *02* IB/M/Jun20/7402/3 Do not write outside the Section A box Answer all questions in this section. You are advised to spend no more than 1 hour and 15 minutes on this section. 0 1 Guppies are small fish. Female guppies are dull in colour. Male guppies can be bright or dull in colour. Scientists investigated the effect of female brain size on choosing a mate. They used laboratory-bred female guppies with large brains and with small brains. They set up a fish tank as shown in Figure 1. Figure 1 They observed each female for 10 minutes and recorded which male they were attracted towards. They repeated this with 45 large-brained females and 45 small-brained females. 0 1 . 1 Suggest three possible limitations of this investigation. [3 marks] 1 2 3 Downloaded by: jessicaonyebuchi | Distribution of this document is illegal S - The Marketplace for Revision Notes & Study Guides 3 *03* Turn over ► IB/M/Jun20/7402/3 Do not write outside the Guppies with large brains are better at identifying predators. box The scientists found that only female guppies with large brains were attracted to male guppies bright in colour. 0 1 . 2 Suggest and explain the advantage of this behaviour to the population of guppies. [3 marks] 0 1 . 3 Describe how the behaviour of female guppies could result in sympatric speciation. [3 marks