Study the diagrams of bird beaks and answer: What type of structures are shown, and why? Name the type of evolution evidence.

1. The diagrams below show beaks of various birds. Study the diagrams and answer the questions that follow.

a) i) The type of structures represented by the diagrams above?

• The diagrams show homologous structures.

a) ii) Give a reason for your answer in (a) (i) above.

• These structures (forelimbs of different mammals) have a similar underlying anatomical structure (e.g., humerus, radius, ulna, carpals, metacarpals, phalanges) but have been modified to perform different functions (e.g., grasping, walking, swimming, flying) in different organisms, indicating a common evolutionary origin.

b) Name the type of evolution evidence