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.
When giraffes walk, they move both legs on one side of their body and then both legs on the other side; this is unique to giraffes. However, they run in a similar style to other mammals, swinging their rear legs and front legs in unison. They can reach 55 km/h (35 mph) at full speed but only in brief spurts.
This highly flexible, yet heavy, body part is integral to the gangly animal's movement. Watch a giraffe and you'll notice that the neck moves back and forth with its stride. That's because the weight and motion of the neck guides the giraffe's center of gravity [source: Dagg and Foster ]. The animal also tosses its neck to and fro to help it rise to a standing position on its spindly legs.