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.
â¢ Shoulder joint & shoulder girdle work together in carrying out upper extremity activities â¢ Shoulder girdle movement is not dependent upon the shoulder joint & its muscles Â© McGraw-Hill Higher Education. All rights reserved. 4-14 Movements â¢ Shoulder girdle muscles â Stabilize scapula so the shoulder joint muscles will have a stable base from which to exert force for moving the humerus â Contract to maintain scapula in a relatively static position during shoulder joint actions â Contract to move shoulder girdle & to enhance movement of upper extremity when shoulder goes through extreme ranges of motion Â© McGraw-Hill Higher Education. All rights reserved. 4-15 Movements â¢ For some shoulder girdle movements, scapula must rotate or tilt on its axis â¢ Lateral tilt (outward tilt) â during abduction