There is a basic body plan common to most of the animals presented in this book. At its most obvious, they all have a head, a body, and four limbs. Most are four-legged and stand on all fours, and are described as having front limbs and rear limbs. The front limb is anatomically equivalent to the arm and hand in humans and primates, and the rear limb to the human lower limb. The animals in this book are surprisingly similar in many ways. The head is connected to the rib cage by the neck vertebrae and the rib cage is connected to the pelvis by the lumbar vertebrae. The two front limbs are connected to the rib cage, and the two rear limbs are connected to the pelvis. These units move in relation to one another, establishing the stance, or pose, of an animal.
Animals differ primarily in the shape and relative proportions of these structural units, in the position of the wrist, heel, and toe bones when standing and walking, and by the number of their toes.
Was this article helpful?