Nearly all mammals have seven cervical (neck) vertebrae. This fact implies that

the answer is:

carbon dioxide

most community's take hundreds of years to become stable

linnaeus is the father of taxonomy

explanation:

which is the system of classifying and naming organisms. one of his contributions was the development of a hierarchical system of classification of nature. today, this system includes eight taxa: domain, kingdom, phylum, class, order, family, genus, and species.