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Ferns may have the ability to “evolve backward” to a more primitive form

Everyone’s seen Rudolph Zallinger’s “The March of Progress” illustration showcasing the evolution of humans: from early primate ape ancestor, Dryopithecus, and progressing toward modern man, Homo sapiens. Evolution is a fascinating phenomenon, but it doesn’t necessarily always follow a straight path as portrayed by Zallinger.

The idea that evolution marches from simple to complex forms, building irreversibly on each prior form has been around for a long time. Paleontologist Louis Dollo’s law states that once an organism progresses with a specialized structure, it does not revert to the previous state.

But now, a new study published in the journal Evolution is challenging the prevailing belief that life progresses unidirectionally. The findings suggest some plants can evolve backward, i.e., specialized species can revert to their more primitive forms.

Post from Isaac Arthur

By popular request we’ve begun adding playlists of the show as Podcasts on Youtube Music, I’ll try to add a new one every 2–3 days till we have most of our inventory up there, but given today’s Episode is *Cities of the Future*, a collection of all of those seemed a good idea https://www.youtube.com/playlist?list=PLIIOUpOge0LuyCbYUhy-79RQKkOXonmx4 These are the (tentatively named) upcoming playlists/podcasts list I’ll be adding, in no particular order: Megastructures & Extreme Engineering The Fermi Paradox & Alien Civilizations Space Colonization & Habitats Post-Scarcity & Future Civilizations Transhumanism & Human Evolution Propulsion & Interstellar Travel Terraforming & Planetary Engineering Mind, Machines & Alien Intelligence Future Warfare & Defense Strange Worlds & Alien Life.

Mammal’s lifespans linked to brain size and immune system function, says new study

So size does matter?

Mammal’s lifespans linked to brain size and immune system function, says new study.

The researchers looked at the maximum lifespan potential of 46 species of mammals and mapped the genes shared across these species. The maximum lifespan potential (MLSP) is the longest ever recorded lifespan of a species, rather than the average lifespan, which is affected by factors such as predation and availability of food and other resources.

The researchers, publishing in the journal Scientific Reports, found that longer-lived species had a greater number of genes belonging to the gene families connected to the immune system, suggesting this as a major mechanism driving the evolution of longer lifespans across mammals.

For example, dolphins and whales, with relatively large brains have maximum lifespans of 39 and up to 100 years respectively, those with smaller brains like mice, may only live one or two years.

However, there were some species, such as mole rats, that bucked this trend, living up to 20 years despite their smaller brains. Bats also lived longer than would be expected given their small brains, but when their genomes were analysed, both these species had more genes associated with the immune system.

The results suggest that the immune system is central to sustaining longer life, probably by removing aging and damaged cells, controlling infections and preventing tumour formation.

Rare silver decay offers scientists a new window into the antineutrino’s elusive mass

Neutrinos and antineutrinos are elementary particles with small but unknown mass. High-precision atomic mass measurements at the Accelerator Laboratory of the University of Jyväskylä, Finland, have revealed that beta decay of the silver-110 isomer has a strong potential to be used for the determination of electron antineutrino mass. The result is an important step in paving the way for future antineutrino experiments.

The mass of neutrinos and their antineutrinos is one of the big unanswered questions in physics. Neutrinos are in the Standard Model of particle physics and are very common in nature. They are produced, for example, by in the sun. Every second, trillions of solar neutrinos travel through us.

“Their mass determination would be of utmost importance,” says Professor Anu Kankainen from the University of Jyväskylä. “Understanding them can give us a better picture of the evolution of the universe.”

Large-scale study explores lifespan changes in the human brain’s functional connectivity

From birth to the last moments of life, the human brain is known to change and evolve significantly, both in terms of its physical organization (i.e., structural connectivity) and the coordination between different brain regions (i.e., functional connectivity). Mapping and understanding the brain’s evolution over time is of crucial importance, as it could also shed light on differences in the brains of individuals who develop various mental health disorders or experience an aging-related cognitive decline.

Researchers at Beijing Normal University and other institutes in China recently carried out a large-scale study to gather new insights into how the brain’s of humans worldwide changes over the course of their lifespan. Their paper, published in Nature Neuroscience, unveils patterns in the evolution of the brain that could inform future research focusing on a wide range of neuropsychiatric and cognitive disorders.

“Functional connectivity of the changes through life,” wrote Lianglong Sun, Tengda Zhao and their colleagues in their paper. “We assemble task-free functional and structural magnetic resonance imaging data from 33,250 individuals at 32 weeks of postmenstrual age to 80 years from 132 global sites.”

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