Starting with a stretch, this first one requires some concentration. We're talking about macro time vs micro time, and one where the time is measured by genetic changes. It's a new way to measure evolutionary time. Also it's scalar, which means fractals:
New research shows microevolution can be used to predict how evolution works on much longer timescales
May 2024, phys.org
By compiling and analyzing datasets from existing species and from fossils, researchers showed the evolvability responsible for microevolution (the evolution of a species over a few generations) of many different traits predicts the amount of change observed between populations and species separated by up to one million years (macroevolution)."Darwin suggested that species gradually evolve, but what we found is that even though populations rapidly evolve over the short term, this (short-term) evolution doesn't accumulate over time. However, how divergent populations and species are, on average, over long periods of time still depends on their ability to evolve on the short term."
via Norwegian University of Science and Technology Department of Biology: Agnes Holstad et al, Evolvability predicts macroevolution under fluctuating selection, Science (2024). DOI: 10.1126/science.adi8722
Further reading, from above: Traits with higher evolvability change rapidly because they are able to respond to environmental changes more quickly.
Highly evolvable traits can rapidly respond to these fluctuations in selection and will fluctuate over time with high amplitude. Traits with little evolvability will also fluctuate but more slowly and thus with lower amplitude.
"Populations or species that are geographically distant from each other are exposed to environments whose fluctuations are not synchronized. Consequently, these populations will have different trait values, and the size of this difference will depend on the amplitude of the trait's fluctuation, and therefore on the evolvability of the trait."
Note: "Evolvability" depends on the amount of heritable (genetic) variation in a species (which sounds like heterozygosity?).
Image credit: AI Art - An Old Man Servicing a Rolex - Dec 2024
Researchers more precisely calculate how much faster time passes on the moon
Jul 2024, phys.org
The team found that time on the moon ticks by at 0.0000575 seconds faster per day (57.50 µs/d) than it does on Earth. Based on that number, other calculations can be made - if a person were to live on the moon for 274 years, for example, they would be 5.76 seconds older than they would be had they lived on Earth all that time.
It doesn't seem like a big deal until you try to do something like dock with a space station.
via NASA's Jet Propulsion Laboratory at the California Institute of Technology: Slava G. Turyshev et al, Time transformation between the solar system barycenter and the surfaces of the Earth and Moon, arXiv (2024). DOI: 10.48550/arxiv.2406.16147
Why timekeeping is now on the verge of a giant leap forward in accuracy
Nov 2024, phys.org
Atomic clocks are about to be replaced by nuclear clocks that can use the Thorium atom instead of the Cesium or Strontium atom, because it has a faster electron transition, so with it we can measure time to the nineteenth decimal place, possibly redefining the second by 2030.
Some background:
- Water clocks appeared around 2,000BC and measure time by regulating the flow of water into or out of a vessel.
- The mechanical clock was established in the late 13th century.
- Until 1967, a second was defined as 1/86,400 of a day.
- The International System of Units then changed things: "The second… is defined by taking the… transition frequency of the cesium-133 atom, to be 9192631770 when expressed in the unit Hz, which is equal to s⁻¹."
Bonus:
Scientists successfully create a time crystal made of giant atoms
Jul 2024, phys.org
via Vienna University of Technology Institute of Theoretical Physics and Tsinghua University: Xiaoling Wu et al, Dissipative time crystal in a strongly interacting Rydberg gas, Nature Physics (2024). DOI: 10.1038/s41567-024-02542-9.
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