Evolving Rocks

SpaceAdmiral notes a new study making the claim that rocks have been evolving throughout Earth's history. "'Mineral evolution is obviously different from Darwinian evolution — minerals don't mutate, reproduce or compete like living organisms,' said Hazen in a statement announcing the study's findings. 'But we found both the variety and relative abundances of minerals have changed dramatically over more than 4.5 billion years of Earth's history. For at least 2.5 billion years, and possibly since the emergence of life, Earth's mineralogy has evolved in parallel with biology,' Hazen added. 'One implication of this finding is that remote observations of the mineralogy of other moons and planets may provide crucial evidence for biological influences beyond Earth.'"

Comments

Re:So we're not 2nd generation?

[Anonymous Coward]

There's nothing in the article saying that. It's just the usual, overly dramatic journalistic nonsense.

And I don't even understand the point of the article. *Chemical* evolution / differentiation of the minerals making up the Earth is a fundamental understanding. How could you not appreciate it when you've got a Great Barrier Reef composed of many cubic kilometres of limestone, there are thousands of comparable examples past and present, and that's only one example of the linkage? Banded iron formations (related to oxygenation of the atmosphere - oxygen produced by photosynthesis), siliceous ooze and chalk (made of the bodies of planktonic organisms), soils in vegetated areas (e.g., affected by organic acids and sediment trapping by roots) -- there are all sorts of areas of interaction, especially because the atmosphere and waters of the Earth are so profoundly influenced by life. And even in the non-biological realm chemical differentiation is why the Earth has a crust and mantle, or why the crust of the continents and oceans is different in composition, for example. People have realized molten rocks and weathered surface sediments experience predictable chemical changes over time, with and without the presence of life, for almost as long as geology has existed as a science.

I'm sure there is something genuinely new in the scientific paper, but the way it's expressed in the press article is awful. It makes it sound like this is something geologists have never thought about or appreciated before.

Re:No its worse than that

[mbone]

If you bother to RTFA, they say that the earth's mineralogy and crustal composition has changed and is affected by biology.

Yes, and this is not news. This would have been news in 1908,
maybe, so as news this is at least century late, probably more.

Now, the America Heritage Dictionary says

evolve
v. tr.
To develop or achieve gradually: evolve a style of one's own.

To work (something) out; devise: "the schemes he evolved to line his purse" (S.J. Perelman).

Biology To develop (a characteristic) by evolutionary processes.

To give off; emit.

Are the rocks developing this gradually ? Are they working out how to adapt to changing oxygen levels ? No. This is like saying "As Christmas approaches, the mall parking lot will evolve to be full of cars." It is a misuse of words (which is different from saying that it is wrong).

Given the politicization of biology, this misuse of words makes me suspicious, but it is more probably just over-enthusiasm.