The biggest division in the living world is between procaryotes-those tiny, simple celled creatures that include things like bacteria-and the eucaryotes, with larger far more complicated cells. And this includes you, gentle reader, for your cells have a marvellous set of apps like an enclosed nucleus, mitochondria, endoplasmic reticulum and a host of other bright shiny things. Which make the poor old bacterial, with its free-floating DNA look like one of those early mobile phones we had back in 1998.
Except of course, the bacterial design is incredibly successful. It probably began 3.5 billion years ago has survived ever since and in terms of biomass, habitat niches and diversity, far outstrips its haughty, but relatively rare, eucaryote rivals. For every blue whale there are billions and billions and billions of bacteria. So why did eucaryotes evolve at all, and when?
Now some really exciting research among microfossils in the 1.9 billion year old Gunflint Chert formations of Canada may give some clues[1] Researchers have found a whole range of fossils that are procaryote in size but begin to exhibit the range and functions we’d normally expect from eucaryotes. It’s as if some transition was going on. And why? Researchers speculate it may have been driven by environmental stresses such as early plate tectonics. But we urge you to read the article by David Bresson of Forbes for yourself. It’s got great pictures, and a reference to the original paper if you really want to wade in deep.
And our takeaway? Up to now, paleontology has been dominated by big fossils you can see, like bits of dinosaurs. Maybe it’s time for more spend on microfossils, like bacteria, pollen grains, chemical residue traces and so on. They might tell us an awful lot more than we know now
#evolution #procaryotes #eucaryotes #precambrian
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