Ordnael
Emperor
I always try to find frogs to play with when I am holidaying at a river! Got some neat pictures and videos with a small frog sitting at my leg trying to catch passing flies!
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Newsworthy Science
- Thread starter Birdjaguar
- Start date
Adding a new layer to evolution.
These findings uncover a property of biological systems even deeper than the evolutionary processes that shape them. They reveal the landscape on which that shaping took place, and they show that it was only possible at all because the landscape has a very specific topology, in which functionally similar combinations of the component parts—genes, metabolites, protein or nucleic-acid sequences—are connected into vast webs that stretch throughout the whole of the multidimensional space, each intricately woven amidst countless others.
One might argue that the original creative act of the living world was the generation of the components themselves: the chemical ingredients, such as amino acids and sugars, that comprise the molecules of life. But this now seems like the easy part, the kind of happy accident that chemistry can supply given the right raw materials and environment. The harder question is how one can get beyond that passive soup to kick-start Darwinian evolution. Manrubia thinks that this primal creative step might itself be a consequence of the richness and intimate interweaving of neutral (or quasi-neutral) networks. This means that, even for random, abiotically generated RNA sequences, there is a significant chance of finding ones that perform some useful function. “In a sense, you have function for free if the phenotypes are sufficiently represented in sequence space,” she says. And her computer simulations show that such RNA sequences aren’t rare. “So sufficiently good solutions to act as seeds of the evolutionary process might arise in the absence of the evolutionary process itself.” In particular, there’s a fair chance of hitting on sequences that can replicate—and then you’re up and running. “Natural selection can very quickly turn mediocre solutions into fully adaptive ones,” Manrubia says.
nautil.us
These findings uncover a property of biological systems even deeper than the evolutionary processes that shape them. They reveal the landscape on which that shaping took place, and they show that it was only possible at all because the landscape has a very specific topology, in which functionally similar combinations of the component parts—genes, metabolites, protein or nucleic-acid sequences—are connected into vast webs that stretch throughout the whole of the multidimensional space, each intricately woven amidst countless others.
One might argue that the original creative act of the living world was the generation of the components themselves: the chemical ingredients, such as amino acids and sugars, that comprise the molecules of life. But this now seems like the easy part, the kind of happy accident that chemistry can supply given the right raw materials and environment. The harder question is how one can get beyond that passive soup to kick-start Darwinian evolution. Manrubia thinks that this primal creative step might itself be a consequence of the richness and intimate interweaving of neutral (or quasi-neutral) networks. This means that, even for random, abiotically generated RNA sequences, there is a significant chance of finding ones that perform some useful function. “In a sense, you have function for free if the phenotypes are sufficiently represented in sequence space,” she says. And her computer simulations show that such RNA sequences aren’t rare. “So sufficiently good solutions to act as seeds of the evolutionary process might arise in the absence of the evolutionary process itself.” In particular, there’s a fair chance of hitting on sequences that can replicate—and then you’re up and running. “Natural selection can very quickly turn mediocre solutions into fully adaptive ones,” Manrubia says.
The Strange Inevitability of Evolution
Good solutions to biology’s problems are astonishingly plentiful.
nautil.us
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Asians made humanity's longest prehistoric migration and shaped the genetic landscape in the Americas
Date:May 15, 2025Source:Nanyang Technological UniversitySummary:An international genomics study has revealed that early Asians undertook humanity's longest known prehistoric migration. These early humans, who roamed the earth over 100,000 years ago, are believed to have traveled more than 20,000 kilometers on foot from North Asia to the southernmost tip of South America. Scientists have mapped the unexpectedly vast genetic diversity of Asians, who make up more than half of the world's population. These findings overturn long-held assumptions of European genetic dominance and show that native South Americans are of Asian descent. The study also sheds light on how such a vast migration and differing environments have shaped human evolution, including how populations have adapted to diseases and how their immune systems have evolved.
Asians made humanity's longest prehistoric migration and shaped the genetic landscape in the Americas
An international genomics study has revealed that early Asians undertook humanity's longest known prehistoric migration. These early humans, who roamed the earth over 100,000 years ago, are believed to have traveled more than 20,000 kilometers on foot from North Asia to the southernmost tip of...
www.sciencedaily.com
PhroX
Deity
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- 2,797
At a glance, it seems like an interesting piece of work, but I'm really confused by this statement:
As, well, this isn't news. I'm pretty sure we've had clear genetic evidence that indigenous Americans are descended from Asian populations for quite some time now. And, frankly, even without genetics, it's kinda obvious, given that they got to American from Asia and have material culture and potentially linguistic connections to other Asian groups.
As far as I know, even things like the (now pretty conclusively disproven) Solutrean Hypothesis wasn't suggesting that European groups were the main ancestral population of the Americans, just that some prehistoric "Europeans" (in quotes as they only comprise a very small part of the ancestry of modern Europeans, who are primarily descended from groups that migrated into the continent later) had crossed the Atlantic and brought their material culture and some amount of interbreeding to the existing population.
As, well, this isn't news. I'm pretty sure we've had clear genetic evidence that indigenous Americans are descended from Asian populations for quite some time now. And, frankly, even without genetics, it's kinda obvious, given that they got to American from Asia and have material culture and potentially linguistic connections to other Asian groups.
As far as I know, even things like the (now pretty conclusively disproven) Solutrean Hypothesis wasn't suggesting that European groups were the main ancestral population of the Americans, just that some prehistoric "Europeans" (in quotes as they only comprise a very small part of the ancestry of modern Europeans, who are primarily descended from groups that migrated into the continent later) had crossed the Atlantic and brought their material culture and some amount of interbreeding to the existing population.
I think much of their point was not that they were of Asian descent, but that over the course of their travels and time, their genetics changed and became less robust.
"The study also sheds light on the evolutionary consequences of such a vast migration. Associate Professor Kim Hie Lim from NTU's Asian School of the Environment, the study's corresponding author, explained that the arduous journey over thousands of years had reduced the genetic diversity of the migrant population.
"Those migrants carried only a subset of the gene pool in their ancestral populations through their long journey. Thus, the reduced genetic diversity also caused a reduced diversity in immune-related genes, which can limit a population's flexibility to fight various infectious diseases," explained Assoc Prof Kim, a Principal Investigator at SCELSE and Vice-Director of GenomeAsia100K."
PhroX
Deity
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- 2,797
Yeah, that does indeed seem to be the focus of the work, which is why I said it was interesting. So why did the summary present the idea that Asians made a long migration into the Americas as news, and have nonsense like "long-held assumptions of European genetic dominance"? (Not criticising you here Birdjaguar, I'm complaining about the awful press release)
EnglishEdward
Deity
Yes, I too have noticed the generally increasing prevalence of discrepancies between A) headlines B) summaries and C) detailed content these days.
Since you are critiqueing the press release I shall point out that this is the work I described earlier.
Why Our Brains Crave Ideology
A neuroscientist reveals how to nurture authentic and flexible thinking
What makes ideology, as you write, the “brain’s delicious answer to the problem of prediction and communication?”
Our brains are these amazingly predictive organs trying to constantly explain the world, because that’s our way to survive. We have to have a reliable model of reality so that we can know what to expect—for example, when there’s going to be a confrontation with someone we’re in a relationship with. Ideologies give us the answers for all those predictions. We don’t have to do that job ourselves, because ideologies say, “Here’s how the world works, how social relationships work. Here are rules of conduct and thought.” We can rely on a compelling story and logical system that many other people are buying into, even if it’s wrong. Ideologies are incredibly seductive because they give us a community of people who we can belong to, and share information with. But that doesn’t mean they’re good for us. Because although that’s all very alluring, research suggests that ideologies can also be very injurious to our capacity for elastic, free, and authentic thought.
Have you studied the basis of cognitive flexibility in the brain?
In a large study that I ran with thousands of participants, we wanted to look at the genetics of rigidity, and what we homed in on was a neurotransmitter that we all know and love—dopamine. We know that dopamine governs our senses of reward, of pleasure, but it does that because it governs our learning. And there’s been a lot of research suggesting that our capacity to adapt is rooted in the functioning of dopamine. So we looked at whether people with genetic variations that affected how dopamine is distributed in their brain, whether those genes could predict people’s cognitive rigidity or flexibility. We found that they did. When people have less baseline dopamine in their prefrontal cortex, and a greater concentration of dopamine in their striatum, the midbrain area that governs learning and reward, that’s a particular genetic profile that puts people at risk for rigid thinking. We found that people with other combinations of these genes typically tended to be much more flexible.
Why Our Brains Crave Ideology
A neuroscientist reveals how to nurture authentic and flexible thinking
nautil.us
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Tea and beer concentrate forever chemicals
Trifluoroacetate (TFA) is an ultrashort-chain perfluoroalkyl substance, which is ubiquitously present in the aqueous environment. Due to its high mobility, it accumulates in plant material. The study presented here shows for the first time that TFA is a widely spread contaminant in beer and tea / herbal infusions.
In 104 beer samples from 23 countries, TFA was detected up to 51 µg/L with a median concentration of 6.1 µg/L. An indicative brewing test and a correlation approach with potassium (K) indicate that the main source of TFA in beer is most likely the applied malt. It could be proven that the impact of the applied water is negligible in terms of TFA, which was supported by the analysis of numerous tap water samples from different countries.
The unintended extraction of TFA was also demonstrated for tea / herbal infusions with a median concentration of 2.4 µg/L.
Trifluoroacetate (TFA) is an ultrashort-chain perfluoroalkyl substance, which is ubiquitously present in the aqueous environment. Due to its high mobility, it accumulates in plant material. The study presented here shows for the first time that TFA is a widely spread contaminant in beer and tea / herbal infusions.
In 104 beer samples from 23 countries, TFA was detected up to 51 µg/L with a median concentration of 6.1 µg/L. An indicative brewing test and a correlation approach with potassium (K) indicate that the main source of TFA in beer is most likely the applied malt. It could be proven that the impact of the applied water is negligible in terms of TFA, which was supported by the analysis of numerous tap water samples from different countries.
The unintended extraction of TFA was also demonstrated for tea / herbal infusions with a median concentration of 2.4 µg/L.
Ordnael
Emperor
[Sips from his cereal sized bowl of tea in the morning, shakes head and chooses to believe that CE compliant products are, somewhat, safer from forever chemicals]
