Which occurs during digestion? O The mouth only allows for physical digestion,
O The mouth only allows for chemical digestion.
O Chemical digestion prepares the food for physical digestion.
O Physical digestion prepares the food for chemical digestion.

i am positive it is c. condensing but i may be wrong

if the type of the food available changes, then the frequency of beak types will change, because birds with beaks more suited to the available food will be more successful over time.

the answer is sex-linked recessive.

not necessarily. higher fitness requires the organism to be reproductive successful. for example, an organism at age 10 with 15 offspring is much more fit than an organism at age 15 with only 5 offspring.