Their very different nervous system is what’s made them hugely interesting to biology recently. Because of their (likely) earlier branching from other elements, it’s very possible then nervous systems evolved at least twice, converged on broadly similar structure, but differ quite a bit in the details.
True! (This stuff is since my BSc and I need to do more reading, but it isn't my job, so there's no time.)
But the thing is that, AIUI, ATP-synthase is in the mitochondria and chloroplasts, so from an evolutionary perspective it is in prokaryotes... just symbiotic ones...
They are us, though. There’s no eukaryotes without mitochondria at all. We are part prokaryote in every cell, apart from the equal number of fully prokaryotic cells in our various microbiomes. Hence the term holobiont for animals like us. We’re pretty much a walking ecosystem.
In some ways, it’s wrong to imagine the branches of life are actually branches. Loki archea and alphaproteobacter together gave us the last eukaryotic common ancestor, and then bacteria continued to live around and in eukaryotes.
That said, mitochondria can’t be called prokaryotes within us. They’ve given up too many genes, and can’t survive on their own.
Of course, the rest of us can’t survive without them either, so it’s a complete mutual situation.
> prokaryotes have been around a lot longer, so they’ve had a lot more evolutionary time to find perfect proteins for their perfect little uses.
I'm not sure that adds up: It's not that much longer - 500 million years out of ~3.5 billion?
And the evidence shows that Eukaryotes have evolved much faster and further - just look at the Eukaryota domain. And IIRC part of the reason is advantages such as 'sexual' [0] reproduction - rather than just splitting and (cloning?) DNA, combining chromosomes from two parents.
A billion to a billion and a half, maybe two billion if it turns out prokaryotes first appeared as far back as 4 billion years ago (jury is out on this too).
But the first complex multicellular life only appears about 1.6 BYA, and sexual reproduction and cell differentiation only about 1.2 BYA.
And no, I wouldn’t say eukaryotes have evolved faster or further, just differently. It’s questionable they’d be able to do any of this without the mitochondrial and chloroplast endosymbiotic events, and microbiomes have existed since the beginning as well. Framing it as a contest misses the point, in the end.
Substrates of consciousness… I think they don’t have it here because they can’t come up with an answer a bunch of AI models will find. Certainly a Millenium problem for biology if there ever was one.
I think it helps Levin is saying something very different. He’s also much more readable for a computer science crowd since his organizing principles are computation adjacent at least, though he, thankfully, isn’t a computational functionalist in the traditional sense.
Eh. Some of these are genuinely interesting problems. Others like cryopreservation and Protein amplification chain reaction are scientifically close to nonsensical.
Rodriques is CEO of Edison scientific, which is going all in on agentic biology. These problems are all benchmarkable, and have been selected to allow for agentic exploration. That is, the tool is driving the problem selection more than genuine value to the field in solving these problems.
Still, if someone takes any of this up and manages something, it’ll be cool.
The brain is a composit of cells from two lineages that separate very early in development and reflect a deeper spatial and functional separation deep in the history of metazoan (read: animal) evolution.
Tying all this to humans specifically is just confusing. This is something that’s seen in a substantial portion of animals, and as such has nothing to do with “ poetry, mathematics and wondering about our own origins”. These features of humans evolved hundreds of millions of years after this two lineage composite organization of animal brains evolved.
I wish the article hadn’t gone out of its way in confusing these issues to push the “relevance” of the research. It’s a pretty remarkable finding anyway.
I’m a materialist. I believe rabbits are conscious. And I can belive there’s a kind of consciousness for a group of humans like a nation state.
However, the United States isn’t just a group of humans. It’s also a group of bison. Wild horses. Flies. Bacteria. Bats. Dung beetles. And whatever entity occupies the White House.
If the United States is conscious, it’s unclear why it’s consciousness stops at its fictitious, human imagined border. Except for humans, no other animal cares or knows when they cross the border.
So a much better claim can be made for the Earth and the entire web of life.
At which point we’re at Gaia hypothesis/Earth Systems science territory, and I’m fine with that too.
I still remain a materialist. And don’t consider the United States to be particularly conscious as an entity.
The United States is not a geographical area, it is an abstract system of organization of humans that largely group together and make rules and modifications to about a geographic area. If all Americans cease to exist, can it really be said that the United States still exists because there are squirrels?
Indeed. Thanks for the great explanation. Honestly, the complexity would be very annoying if it wasn’t also invigorating and fascinating.
The interconnections between genes has led to proposals of “omnigenic” models, the idea that all genes expressed in a cell affect every given trait of the cell, to some extent.
When it comes to something like autism, it’s a word covering a vast number of traits and behaviors of many different cells that gives rise to that set of effects as seen from outside.
And the issue with genetic testing is, we often only look at specific regions of the genome. Even when we do whole genome tests, and compare whole genomes of autistic folks, what we find is no single origin but many overlapping patterns. No definitive set is found because we are looking at complex processes that have many nodes where mutations can mildly tweak the function. Many such functionally relevant mutations can chain together to give you the signatures of autism, and no two are the same.
All these reasons also point to why we are increasingly realizing autism isn’t a “disease” with a “cure”. It’s a way in which people can be people. It’s time society accepted that and expands itself to accommodate.
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