"What they found may have implications for the origin of complex life.
The air, which has been preserved, undisturbed, in tiny pockets in the crystals for about 815 million years, appears to contain 10.9 per cent oxygen — just half the amount in the atmosphere today.
But it's about five times more than scientists expected for that time period, which is about 200 million years before the first known multicellular fossils."
> 200 million years before the first known multicellular fossils
This is a weird angle for the article to pursue. We have a monocellular fossil record that dates back 4.1 billion years, and I don't think anyone is proposing that we assumed up to this point oxygen levels took off because of multicellular life. A high oxygen level is probably one of many prerequisites for complex life, but that doesn't mean the genetic machinery was available as soon as it reached a certain concentration.
That was my understanding as well. The idea being that there is a lot of volume in the first few meters of ocean surface area churn. It's not hard to imagine that does better in surface area than (even a lot) of plants.
Not forgetting the fact that it seems like it would be substantially easier for a faintly mobile fluid filled bag(s) of DNA to survive and reproduce in an aqueous environment!
If my college biology understanding of evolution is at all accurate, a functional oxygen pathway would provide an edge in the ecosystem (read: high rates of population growth) and may have, in fact, been a catalyst for multi-cellular growth.
The most recent discussion I heard seemed to be the theory that a functional oxygen pathway enabled multicellular life by providing enough surplus energy to power the entire organism in an evolutionarily efficient manner. (Add in the fact that by that point the planet was also teeming with single celled biomass to consume)
The air, which has been preserved, undisturbed, in tiny pockets in the crystals for about 815 million years, appears to contain 10.9 per cent oxygen — just half the amount in the atmosphere today.
But it's about five times more than scientists expected for that time period, which is about 200 million years before the first known multicellular fossils."