Two bird species eat the same seeds. Species X arrives in a habitat occupied by species Y. X does not eat Y or transmit disease to it.
After several years, Y survives only in small, widely separated groups. Few young Y birds are produced even where some seeds remain.
Which explanation best links the arrival of X to the low production of young Y birds?
Competition reduces Y numbers, so surviving Y birds have more available mates.
Competition reduces Y numbers, so surviving Y birds have fewer available mates.
Predation reduces Y numbers, so surviving Y birds have fewer available mates.
Predation reduces Y numbers, so surviving Y birds have more available mates.
63 exam-style questions on AQA GCSE Biology 7.1 Adaptations, interdependence and competition, covering 7.1.1 Communities, 7.1.2 Abiotic factors, 7.1.3 Biotic factors, and 7.1.4 Adaptations. Each one has a worked solution and a mark scheme showing where the marks go.