Natural Selection and Vertebrae

The expression "built for speed" applies to more than just machinery. A study of the vertebrae in mammals' skeletons had some interesting results. Creatures that are built for speed tend to have little variation in different kinds, but the slower animals that do not rely on speed for survival have more variation. The study was an example of natural selection.


Natural selection does not mean molecules-to-man evolution. Instead, it weeds out the unfit and preserves organisms within genetic limitations; it does not add new genetic information to enable an organism to turn into something else. Interestingly, this study had a result that the scientists did not plan: It supports the work of the Designer, not evolution.
Why is the number of vertebrae in the trunk of mammals, despite diverse lifestyles, “surprisingly constant”? Evolutionary biologists investigating biodiversity want to know.

To solve this riddle, Frietson Galis of Leiden’s Naturalis Biodiversity Center and colleagues examined the skeletons of 90 different mammalian species—774 specimens housed at 9 different natural history museums—assessing how much the shape and number of vertebrae in each section of the back varied. They found that there is minimal variation among fast, agile mammals, even up to the family level. Slower mammals are less consistent.
To read the rest, hurry on over to "Run For Your Life! Evolution’s Solution".