Many birds migrate south for the winter in search of food

true                                                                                                       true true true true true true

plato users:

d.  

there was a variety of food available on island x, but there were only large seeds and nuts on island y.

air enters through the nose, moves through the nasal cavity, the pharynx, the larynx, enters the trachea, moves through the bronchi andbronchioles till the alveoli.

the oldest known insects are believed to live around 400 millions ago as suggested by the fossil records.   some plants having woody stems also evolved during this time.

after the evolution of insects the first four legged species or the tetrapods evolved in shallow freshwater habitats from the intermediate species approximately 397 million years ago. the tetrapods went on conquering the land giving rise to amphibians, reptiles, mammals and birds.

the major split in tetrapods first occurred 340 million years ago branching off from amphibians.

363 million years ago when the carboniferous period began the insects started roaming on land and taking flights, following which the four limbed tetrapods adapted in the terrestrial habitat.