New insight into the evolution of complex life on Earth


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Sulfolobus acidocaldarius thrives in geothermal mud pools like this one in New Zealand. Credit: Lancaster University

A novel connection between primordial organisms and complex life has been discovered, as new evidence sheds light on the evolutionary origins of the cell division process that is fundamental to complex life on Earth.

The discovery was made by a cross-disciplinary team of scientists led by Professor Buzz Baum of University College London and Dr. Nick Robinson of Lancaster University.

Their research, published in Science, sheds light on the cell division of the microbe Sulfolobus acidocaldarius, which thrives in acidic hot springs at temperatures of around 75 C. This microbe is classed among the unicellular organisms called archaea that evolved 3.5 billion years ago together with bacteria.

Eukaryotes evolved about 1 billion years later—likely arising from an endosymbiotic event in which an archaeal and bacterial cell merged. The resulting complex cells became a new division of life that now includes the protozoa, fungi, plants and animals.

Now a common regulatory mechanism has been discovered in the cell division of both archaea and eukaryotes after the researchers demonstrated for the first time that the proteasome—sometimes referred to as the waste disposal system of the cell—regulates the cell division in Sulfolobus acidocaldarius by selectively breaking down a specific set of proteins.

The authors report: "This is important because the proteasome has not previously been shown to control the cell division process of archaea."

more at link....................

the paper:

The proteasome controls ESCRT-III–mediated cell division in an archaeon

Proteasomal control of division in Archaea
In eukaryotes, proteasome-mediated degradation of cell cycle factors triggers mitotic exit, DNA segregation, and cytokinesis, a process that culminates in abscission dependent on the protein ESCRT-III. By studying cell division in an archaeal relative of eukaryotes, Tarrason Risa et al. identified a role for the proteasome in triggering cytokinesis by an archaeal ESCRT-III homolog. Cell division in this archaeon was driven by stepwise remodeling of a composite ESCRT-III–based division ring, where rapid proteasome-mediated degradation of one ESCRT-III subunit triggered the constriction of the remaining ESCRT-III–based copolymer. These data strengthen the case for the eukaryotic cell division machinery having its origins in Archaea.

Science, this issue p. eaaz2532
The teeth of ‘wandering meatloaf’ contain a rare mineral found only in rocks
The giant Pacific chiton’s use of santabarbaraite could inspire materials for soft robotics

The teeth of the world’s largest chiton (Cryptochiton stelleri), nicknamed "the wandering meatloaf” for its charismatic looks (shown), possess a rare mineral once found only in rocks.

While it sounds like a tour update for the musician Meat Loaf, this research concerns a large mollusk called a chiton (not a "bat out of hell"). The mollusk, also known as Cryptochiton stelleri, got its nickname because it's large, reddish-brown and, well, shaped a bit like a meatloaf escaping the pan. It lives along rocky coastlines. The largest chiton in the world, it can reach 13 inches in length.
Researchers were surprised to find santabarbaraite in the mollusk's tooth because it's previously been found only in rocks.
Chiton need tough teeth because they essentially chew on rocks to scrape off algae and other food substances. Their teeth are one of the hardest materials in nature and are attached to a flexible tongue-like structure called a radula.
Is this an example of hive behavior in plants? If so , that would yet be another proof of evolutionary processes. Another bridge in abiogenesis of life and consciousness.

These ferns may be the first plants known to share work like ants
The plants may form a type of communal lifestyle never seen outside of the animal kingdom


Many of this fern colony’s fan-shaped nest fronds (growing closer to the tree trunk) are sterile, while the thinner strap fronds (sticking up and out from between the nest fronds) lift more of the reproductive load for the colony. IAN HUTTON

By Jake Buehler, JUNE 7, 2021 AT 6:00 AM

High in the forest canopy, a mass of strange ferns grips a tree trunk, looking like a giant tangle of floppy, viridescent antlers. Below these fork-leaved fronds and closer into the core of the lush knot are brown, disk-shaped plants. These, too, are ferns of the very same species.
The ferns — and possibly similar plants — may form a type of complex, interdependent society previously considered limited to animals like ants and termites, researchers report online May 14 in Ecology.
Kevin Burns, a biologist at Victoria University of Wellington in New Zealand, first became familiar with the ferns while conducting fieldwork on Lord Howe Island, an isolated island between Australia and New Zealand. He happened to take note of the local epiphytes — plants that grow upon other plants — and one species particularly caught his attention: the staghorn fern (Platycerium bifurcatum), also native to parts of mainland Australia and Indonesia.
“I realized, God, you know, they never occur alone,” says Burns, noting that some of the larger clusters of ferns were massive clumps made of hundreds of individuals.

Note that Ferns are one of the oldest living species on earth and had plenty of time to evolve very complex living patterns. Moreover Ferns are one of the purest fractal organisms on earth.