Population ecology is the study of these and other questions about what factors affect population and how and why a population changes over time. Population ecology has its deepest historic roots, and its richest development, in the study of population growth, regulation, and dynamics, or demography.
While running, the neck of a giraffe moves backward and forward to keep the animal balanced. Giraffes have a top speed of about 56 kilometres per hour (35 miles per hour), however, because its legs are so long a galloping giraffe does not appear to be going very fast.
Giraffes are characterized by a long neck and long front legs. The neck can grow to a length of 6 feet, and it accounts for one-third of the body weight of the giraffe. The giraffe feeds on dry grass and can reach up to devour leaves at tall heights.