What special feature allows birds to fly?

Instead of heavy jaws and teeth, they have lightweight beaks. And instead of fur, they have feathers. These are light, streamlined and cleverly adjustable for flight control. Their bones are also hollow (pneumatised) making them lighter for flight.

Explanation:

lol its to easy and almost common sense

flooding wildfire landslides climate change the factors listed have an immediate effect on the animal populations found in any habitat. the four factors would lead to a death. b emigration. eliminate c immigration. d mutations.