Answer: Organisms are born with variation.
Answer:
The correct answer will be-ventral ramus
Explanation:
Rectus abdominis is a skeletal muscle found in the front part of the body which begins from the sternum and ends at the pubic zone.
Rectus abdominis is also known as "Abs" which viewed externally appears to be six, eight or ten in number.
These muscles are innervated by the thoracoabdominal nerves which carry and transmit signals to CNS and to the muscles back. The main spinal nerve which controls the movement of Abs is known as the "ventral ramus".
Thus, ventral ramus is the correct answer.
Answer:
Positive natural selection.
Explanation:
The positive natural selection is a type of natural selection that increases the frequency of an allele or trait when it is advantageous for the population. What happened in the example is that the mouth with the slight change in morphology (trait) was more advantageous for the population in the south in relation to the ancestral morphology (still preserved in the population in the north), and therefore its frequency increased. This, in turn, is due to the fact that the food (prey) is not the same in the two habitats (north and south). The specific prey in the south, caused the new morphology to be selected, (increasing the frequency of individuals with the new mouth), becasue probably that trait allows the trouts in the south to hunt more effectively.