[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.
This is a collection of quotations from Don Patton on the subject of evolution.
The original collection of quotations can be found at
This document lists the same quotations, but includes the surrounding context (usually just the paragraph in which Patton's quotation occurs).
I do not know when this collection was assembled, but it appears to be around 1994, judging by the date of the most recent source.
Bold text represents the part of the passage quoted by Don Patton (my apologies to Lynx users, who may see both bold and italic text as underlined.
One good reason might be that many of these animals had only soft parts to their bodies: no shells or bones to fossilize.
— Richard Dawkins, Until recently, vertebrates have been known from rocks no older than the Middle Ordovician (about 450 million years ago) (1, 2).
In 19 the known range of the vertebrates was extended back about 20 million years by discoveries of fish fossils in rocks of latest Early Ordovician and earliest Middle Ordovician age in Spitzbergen (3, 4) and Australia (5).
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.