Question

As the final part of her study, Linda wants to know how the extinction of pterosaurs impacted the diversification of living bird groups. She knows that the fossil record is incomplete, and that it will be difficult to study this question using fossils alone. She therefore teams up with a geneticist to reconstruct the evolution of modern birds: Feet modified for perching 9 Owls 107 A -Parrots 19 -Penguins 4 Chickens TL 6 Doves Enlarged breastbone Grebes 19E B Flamingos Feathers modified for freshwater habitat Figure 6: Molecular phylogeny of modern birds. The number of genetic mutations separating each branch in the tree is noted with a number. Several noteworthy synapomorphies are noted with arrows.

Answer 1

Question no.35:

Answer: node B Explanation: Mopsitta having feet modified for perching can be placed in node A but the body it has is adapted to swim in salt water which makes it different from the birds present in node A. So, Mopsitta shares more features with birds which has long beaks and can survive in salt water condition as like Penguins (who are adapted from freshwater to salt water).

Question no. 36:

Answer: 30 million years old

Question no. 37:

Answer: ~1 mutation every 1.5 million years

Question no. 38:

Answer:~ 30 million years old