How radiometric dating supports the theory of evolution
Before we come to the sort of sudden bursts that they [Eldredge and Gould] had in mind, there are some conceivable meanings of `sudden bursts' that they most definitely did not have in mind.
These must be cleared out of the way because they have been the subject of serious misunderstandings.
This is a collection of quotations from Don Patton on the subject of evolution.
The original collection of quotations can be found at
Eldredge and Gould certainly would agree that some very important gaps really are due to imperfections in the fossil record. For example the Cambrian strata of rocks, vintage about 600 million years, are the oldest ones in which we find most of the major invertebrate groups.
And we find many of them already in an advanced state of evolution, the very first time they appear.
[Patton introduces an ellipsis, apparently solely to mark the beginning of a new paragraph.] If the carbon dioxide dissolved in sea water decreases, some bicarbonate ions change to carbonate, thereby causing precipitation of calcium carbonate. Most are biogenic, and consist primarily of microscopic or macroscopic shells (or at least these make up a considerable fraction, and often almost all, of the rock volume).
The precipitate forms a fine, crystalline cloud which settles to the bottom. This is true of limestone production today too, most of which is in association with biological activity.
Because of these relations, there is a direct connection between atmospheric carbon dioxide and the amount of dissolved calcium ion in sea water. One look at the rest of any texbook on sedimentology, and you will realize that most limestonare not inorganic anyway.
The chapter from which this quotation is taken deals with the ``controversy'' between gradualism and punctuated equilibrium.
Dawkins's point is that the argument is trivial, compared to the amount of media furor it has raised.
These contingencies will concur only rarely, and after enormously long intervals.
Whilst the bed of the sea is stationary or is rising, or when very little sediment is being deposited, there will be blanks in our geological history.