Sugar, water, and other food molecules.
HOXC8 gene encodes a protein that has a role in the development of the cartilage. This gene is a member of the HOX group gene that enables the differentiation of the body segments. These genes encode for transcription factors that activate the expression of other specific genes guiding the differentiation of body segments into specific structures.
<h2>Answer:</h2>
The two reasons are given below:
- Natural selection.
- Lack of food
<h3>Explanation:</h3>
Natural selection is the phenomenon of the evolution in which the organisms able to fit in the changing environment survive while other organism died. Hence the survival if the fittest and then these organisms. Further reproduce to give birth organisms more fit to the changing environment.
The long neck giraffe survive but short neck died. So the population of long neck increased while short neck go extinct.
Other reason is the change of food resource. The food resource change from grass to long trees.
