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A comment on Why Is the Ocean Salty?. Parent comment

Re:Why Is the Ocean Salty? by eru on Monday September 11, 2023 @03:01AM (#37463868)
> I raised and homeschooled two kids and watched a lot of when dinosaurs ruled the earth type stuff. That's my source for the idea that a store of calcium was critical for allowing life to leave the ocean and I've tried repeatedly to search for additional info on this and can never find it.

Insects and friends manage to live on land just fine without any calcium bones.

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Re:Why Is the Ocean Salty? by DoreenMichele on Monday September 11, 2023 @03:07AM (#37463914)
Dragonflies used to get to a two-foot wingspan. They don't anymore. The atmosphere was thicker and contained more oxygen.

What works once life is established on land can be different from what it took to transition to land and that's what I'm asking about.

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Re:Why Is the Ocean Salty? by eru on Monday September 11, 2023 @03:14AM (#37463963)
There was more oxygen in the air when the dinosaurs roamed, but not when insects (and other critters) first came on land.

https://forces.si.edu/atmosphere/02_02_06.html says

> As plants became firmly established on land, life once again had a major effect on Earth’s atmosphere during the Carboniferous Period. Oxygen made up 20 percent of the atmosphere—about today’s level—around 350 million years ago, and it rose to as much as 35 percent over the next 50 million years.

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Re:Why Is the Ocean Salty? by DoreenMichele on Monday September 11, 2023 @03:16AM (#37463974)
Irrelevant.
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Re:Why Is the Ocean Salty? by eru on Monday September 11, 2023 @03:22AM (#37464018)
Huh?

The high oxygen levels you mentioned occurred long after life had successfully made its way on land.

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