They are multicellular, heterotrophic, they have no respiratory organs, and their digestion is intracellular!
<span> phylum .....................</span>
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.
The answer is chromosome ....
