BIOLOGY 5090 · STRUCTURED PRACTICE
A team of field biologists studies four species of tree frogs inhabiting a tropical rainforest ecosystem: Agalychnis callidryas (Red-eyed tree frog), Agalychnis spurrelli (Gliding tree frog), Dendropsophus ebraccatus (Hourglass tree frog), and Boana rufitela (Canal Zone tree frog).
Define the term species.
State the two taxonomic ranks used in the binomial name Agalychnis callidryas and explain one advantage of using international binomial names rather than local common names.
Complete the dichotomous key below by writing appropriate morphological statements for step 1 and step 2 to identify Agalychnis callidryas from the other tree frog species based on the following diagnostic traits:
- Agalychnis species possess webbed feet and bright red/orange iris coloration.
- Dendropsophus ebraccatus possesses yellow-patterned dorsal skin and dark brown iris coloration.
- Boana rufitela possesses unpatterned green skin and pale yellow iris coloration.
Explain why comparing DNA base sequences provides more accurate evidence for evolutionary relationships than comparing external physical features alone.
Total: 8 marks