On the whole, it might be easier to conclude that the timing is somewhat off than that complex life started without oxygen. But symbiosis is an intriguing theory nonetheless.
Tag: bacteria
Animal DNA modifier captured from bacteria 60 million years ago
The obvious question this raises is, what about all the detailed Darwinian narratives that a horizontal gene transfer could obviate?
Largest bacterium ever discovered is as big as a peanut
Tim Standish: If prokaryotes have the capacity to develop very complex cells, why didn’t they do what eukaryotes did and turn into multicellular organisms, assuming there is some sort of fitness advantage to doing so? Why would being multicellular increase fitness in eukaryotes and not bacteria or archaea?
A scare from New Scientist: Melting permafrost could release ancient viruses that cause the next pandemic
The basis for such panic marketing is usually a correct science observation — in this case, that microscopic life forms (and viruses) may hibernate for long periods in ice. However, as the New Scientist article notes, “bacteria that infect humans are adapted to live at our body temperatures, so it is highly unlikely that they would survive for long periods below zero.”
At Mind Matters News: Would cognition in bacteria “dethrone” humans?
Takehome: Of course we can “see ourselves” as an earthworm. But it doesn’t work in reverse. And Pamela Lyon sheds no light on that fact, apart from denigrating humans.
Horizontal gene transfer: Bacteria apparently despise the selfish gene
Researchers: “Cooperation is ubiquitous in bacterial populations. Bacteria produce and share public goods, providing indiscriminate benefits to their neighbors at cost to themselves.” It makes sense but it isn’t yer old biology teacher’s evolution.
Researchers: “Positive interactions are common among culturable bacteria”
And here we thought nature was “red in tooth and claw.” From the paper: “We find that positive interactions, often described to be rare, occur commonly and primarily as parasitisms between strains that differ in their carbon consumption profiles.”
Paper on bacterial mobility (motility) doesn’t invoke “evolution”
Which raises a question: How much outgassing about “evolution” is intended to stifle curiosity and make it sound like we know things we don’t?
Researchers: The last bacterial common ancestor had a flagellum
Question: If the last common ancestor of the bacterium had a flagellum, what do we really know about the evolution of the flagellum? Isn’t that a bit like finding a stone laptop in a Neanderthal cave? That said, it’s nice to see horizontal gene transfer getting proper recognition.
Researchers search for the “last bacterial common ancestor” in a world of horizontal gene transfer
One senses that the reconstruction will be subject to considerable revision. It’s not entirely clear what “ancestry” means in a world of rampant horizontal gene transfer.
At Scientific American: How some bacteria have achieved “immortality”
At Scientific American: In this experiment, cells awoke and multiplied that settled to the bottom when pterosaurs and plesiosaurs drifted overhead. Four geologic periods had ground by, but these microbes, protected from radiation and cosmic rays by a thick coat of ocean and sediment, quietly persisted. And now, when offered a bite, they awoke and carried on as if nothing unusual had happened.
At Mind Matters News: Can insects have personalities too?
What about bacteria? If personality amounts to observed individual differences in behavior, the answer is yes.
Bacteria “convince” their squid host to change gene expression to make life easier for the bacteria
Clever little things, aren’t they? Change the host’s genome? So much intelligence in nature and it is supposedly all just an accident. Sure.
Bacterium alters its genome to adapt to new conditions
Researchers: Achromatium is special in many respects: It is 30,000 times larger than its “normal” counterparts that live in water and owing to its calcite deposits it is visible to the naked eye. It has several hundred chromosomes, which are most likely not identical. This makes Achromatium the only known bacterium with several different genomes.
At Science News: Top Ten wrong results in science
Many of the mistakes listed seem just to be natural, though incorrect, assumptions of their day. This arsenic-based life though, now that was intriguing, if wrong.