Answer:
Changes in the environment affect the food sources available for birds. For example, if a flood was to occur, there would be an abundance of fish to birds to eat. So birds with bigger beaks will be able to eat fish, to live and reproduce offspring with bigger beaks. While birds with smaller beaks will not be able to catch fish to eat, therefore decreasing the population of birds with smaller beaks.
Answer:
Messenger Ribonucleic Acid.
Explanation:
Water has high surface tension because of the high attraction between it's molecules
