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"My Point is that ‘Why is Nothing Evolving NOW?’"

In his book, "Angels and Ages", Adam Gopnik introduces a concept by way of his introduction:

The middleweight champion [of the early twentieth century, Stanley Ketchel] was stunned by [Wilson] Mizner's recitation of the Langdon Smith classic that starts "When you were a tadpole and I was a fish, In the Palaeozoic time" and follows the romance of two lovers from one geological age to another, until they wind up in Delmonico's.

Ketchel had a thousand questions about the tadpole and the fish, and Mizner, a pedagogue at heart, took immense pleasure in wedging the whole theory of evolution into the fighter's untutored head.

Ketchel became silent and thoughtful. He declined an invitation to see the town that night with Mizner and [Willus] Britt. When they rolled in at 5 a.m., Ketchel was sitting up with his eyes glued on a bowl of goldfish.

"That evolution is all the bunk!" he shouted angrily, "I've been watching those fish nine hours and they haven't changed a bit."

Mizner had to talk fast; one thing Ketchel couldn't bear was to have anybody cross him.
-Alva Johnston, The Legendary Mizners

Since evolution, if it is to occur at all, has to occur from one generation to the next, or across many, many generations, if you want to be able to observe it happening in your lifetime, then you will have to either have a very long lifetime, or observe creatures with very short lifetimes.

This is why many evolutionary studies follow the development of simple, short-lived lifeforms, such as bacteria or fruit flies, (Drosophila melanogaster).

Some bacterial strains have been followed for twenty years!

If you are interested in human evolution, you can read the reports that humans have made in describing others of their species, as well as examinations of skeletal remains from individuals of known histories.

Arguably, examining skeletons of less-certain histories may introduce errors in computing the rates of change, but changes are easier to observe in them.

One thing that is clearly changing in humans is our teeth. We have been shedding the larger and more aggressive or useful teeth of our predecessors because we have been benefiting from processing our foods more. Such things as cooking make food easier to eat, as well as to digest.

These changes are not happening to groups at the same rate. It is an interesting study. Some families have variations in the number of teeth, or the number of cusps on teeth, that would indicate they are changing either at a different rate or along a different path.