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Can you tell us about the nitrogen cycle and its significance for the ecosystem?

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Well, one of the key features for life to be possible on the planet would be the capacity

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to take nitrogen and to fix it, to convert it into a form that organisms could use as

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a source of nitrogen.

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And the process of nitrogen fixation is a very elaborate biochemical process that is absolutely

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critical for life to exist.

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And so it's got to be one of the very first metabolic systems that would emerge.

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And bacteria are playing a key role in nitrogen fixation.

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What's interesting is many biologists believe that nitrogen fixation appeared also very early

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in the history of life on Earth along with photosynthesis.

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In fact, the metabolic pathways that drive photosynthesis actually conflict with the metabolic

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processes that drive nitrogen fixation.

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So those two processes have to be separated, and the way that bacteria separate them is

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through what are called circadian rhythms, where during the night nitrogen fixation takes

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place, during the day photosynthesis takes place.

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And that elaborate regulation of those two processes, to me, defies an evolutionary explanation

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and is something that I think, again, reflects a creator's handiwork.

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Yes.