1. Discussion on PZ Myers being expelled from Expelled

Comment #152372 by bichard on March 30, 2008 at 8:53 pm

This clip is pleasant to watch and I am pleased that Dr. Dawkins and Dr. Myers were so high minded and calm about things.

However, it has been pointed out elsewhere that the associations made by this 'film' are truly insidious and mean spirited, it is propaganda pure and simple and of the lowest kind imaginable.

The goal of the people who constructed this is simple minded and plain, to reinforce the meme darwin = atheist = holocaust. Never mind the fact that Hitler was a christian and took more from Martain Luther than from Darwin in constructing his programs for racial purity. Never mind that both atheists and theists can realize that evolution is both a fact and a viable theory that explains that fact, and never mind that Darwin no matter what his personal character, the effects of his works, or the distortions of his ideas by others, discovered the concept that underpins and unifies all biology in a manner equivalent to the way general relativity and quantum mechanics unify physics.

This is not a scientific debate, it is politics, and gutter politics at that. I think it is time for the scientific constituency to question their politicians and see if they are willing to defend reasoned deliberations over issues or cowardly hide behind proclaimations of divine insight.

2. The Oxford Book of Modern Science Writing

Comment #144857 by bichard on March 16, 2008 at 9:34 pm

Wonderful.

Thank you again Dr. Dawkins for another portal to new and important knowledge.

3. Diamonds unlock secrets of early Earth

Comment #86252 by bichard on November 8, 2007 at 8:43 pm

Well... just a bit of technical nit picking. Diamonds by definition are not "fragments of the earth's crust". The upper limit of the diamond phase stability field for carbon in temperature pressure space is 35,000 atmospheres more or less and would
probably have been even higher in the Hadean as it is plausible that the mantle would have been at higher temperatures. In present day terms that kind of pressure corresponds to a depth of about 150 km, far deeper than any present day crust.

Further while it is true that 4.0+ billion y.o. diamond is a new upper limit for terrestrial diamonds, 3.0+ ages have been known for some time.

By logic alone it is clear that eventually diamonds
as old as the earth itself might be found since all that is required for them to have formed is the right chemistry, and sufficient pressure. What is lacking in the article as reported is any evidence that these diamonds were erupted to the surface in the time range suggested. All diamonds are older than their age of eruption, usually much older.

I wasn't able to find the link in Nature because it was too general, perhaps the actual paper reporting these results provides evidence the diamonds were actually erupted in this time frame.

One more nitpick that troubles me, the article mentions the diamonds were included in zircons, this I find a bit of a stretch as zircon is a silicate mineral formed at low pressure and high temperature in an oxidizing environment. Diamonds oxidize readily at low pressure and high temperature unless the environment is highly reducing. Given that the source is CNN its certainly possible that the reporter juxtaposed the phase arrangement and that the zircons were included in the diamond. Also it is much easier to date zircon than diamond. But that then raises the question were the zircons dated instead of the diamond and if so, the diamond could have formed almost anytime after the zircons.

I find this article too simplified and confused to carry much credibility and a direct cite to the nature paper would have been much more meaningful I would hope.

To Nebularry - IMO no it wouldn't. Given the energetic state of the early earth, it would not be at all surprising if "crustal type rocks" were formed very early in its history. More important would be the presence of liquid water.

Sorry to be so late in replying but until recently I have not been able to post comments due to a browser glitch which the maintainers have fixed I am pleased to note.

Cheers all -