FIGURE 3-1 Size discrepancy between the rat and the human spinal cords.
The human spinal cord is more than four times as long as the entire CNS of the rat. (A) A caudal segment of the human spinal cord, including the cauda equina. The human cauda equina is approximately the same length as the entire CNS of a rat, which includes its brain. (B) The diameter of the human spinal cord is also much larger than that of the rat spinal cord. Twenty slices of a rat spinal cord can fit inside one slice of a human cord.
SOURCE: Reprinted with permission, from Dobkin and Havton, 2004. Copyright 2004 from Annual Reviews.