Jul 4, 2022 08:14 PM
(This post was last modified: Jul 4, 2022 08:24 PM by C C.)
Biology's uncertainty principle
https://iai.tv/articles/biology-uncertai...-auid-2170
INTRO: You’ve heard of stem cell research and its promise of a medical revolution given the regenerative abilities of stem cells. But as it turns out, identifying what a stem cell is experimentally is not at all straightforward. Stem cells have two main abilities: cell renewal (division and reproduction) and cell differentiation (development into more specialized cells). The main problem is, there is no way to experimentally test whether one particular cell can both self-renew and differentiate to make more developed kinds of cells. Much like Heisenberg’s uncertainty principle, according to which we can’t measure a particle’s velocity and position at the same time, we can’t measure both properties that constitute a stem cell. Claims that any single cell is a stem cell are therefore inevitably uncertain, argues Melinda Bonnie Fagan... (MORE - details)
Explosion of life on Earth linked to heavy metal act at planet’s centre
https://www.theguardian.com/science/2022...ets-centre
INTRO: At the centre of the Earth, a giant sphere of solid iron is slowly swelling. This is the inner core and scientists have recently uncovered intriguing evidence that suggests its birth half a billion years ago may have played a key role in the evolution of life on Earth.
At that time, our planet’s magnetic field was faltering – and that would have had critical consequences, they argue. Normally this field protects life on the surface by repelling cosmic radiation and charged particles emitted by our sun.
But 550m years ago, it had dropped to a fraction of its current strength – before it abruptly regained its power. And in the wake of this planetary reboot, Earth witnessed the sudden proliferation of complex multicellular life on its surface. This was the Cambrian explosion, when most major animal groups first appeared in the fossil record. Now scientists have linked it to events at the very centre of the Earth... (MORE - missing details)
When did Earth's first forests emerge?
https://www.livescience.com/when-did-fir...sts-emerge
INTRO: From Earth's tallest living plants, California's redwoods, to the planet's largest tropical rainforest, the Amazon, stately forests may seem timeless. But like every species or ecosystem, they have a birth date. In fact, though plants first arrived on land about 470 million years ago, trees and forests didn't hit the scene until nearly 390 million years ago.
During that interval, plant life slowly evolved genetic precursors needed to produce trees, which then outcompeted other plants, Chris Berry, a paleobotanist at Cardiff University in the United Kingdom, told Live Science.
In 2019, Berry and colleagues reported on the oldest forest on record, in the journal Current Biology. This forest, uncovered in Cairo, New York, revealed that features characteristic of trees and forests — namely wood, roots and leaves amid a population of dozens of plants — appeared "far earlier than previously suspected": in the early Devonian period, 385 million years ago, the researchers said in the study... (MORE - details)
https://iai.tv/articles/biology-uncertai...-auid-2170
INTRO: You’ve heard of stem cell research and its promise of a medical revolution given the regenerative abilities of stem cells. But as it turns out, identifying what a stem cell is experimentally is not at all straightforward. Stem cells have two main abilities: cell renewal (division and reproduction) and cell differentiation (development into more specialized cells). The main problem is, there is no way to experimentally test whether one particular cell can both self-renew and differentiate to make more developed kinds of cells. Much like Heisenberg’s uncertainty principle, according to which we can’t measure a particle’s velocity and position at the same time, we can’t measure both properties that constitute a stem cell. Claims that any single cell is a stem cell are therefore inevitably uncertain, argues Melinda Bonnie Fagan... (MORE - details)
Explosion of life on Earth linked to heavy metal act at planet’s centre
https://www.theguardian.com/science/2022...ets-centre
INTRO: At the centre of the Earth, a giant sphere of solid iron is slowly swelling. This is the inner core and scientists have recently uncovered intriguing evidence that suggests its birth half a billion years ago may have played a key role in the evolution of life on Earth.
At that time, our planet’s magnetic field was faltering – and that would have had critical consequences, they argue. Normally this field protects life on the surface by repelling cosmic radiation and charged particles emitted by our sun.
But 550m years ago, it had dropped to a fraction of its current strength – before it abruptly regained its power. And in the wake of this planetary reboot, Earth witnessed the sudden proliferation of complex multicellular life on its surface. This was the Cambrian explosion, when most major animal groups first appeared in the fossil record. Now scientists have linked it to events at the very centre of the Earth... (MORE - missing details)
When did Earth's first forests emerge?
https://www.livescience.com/when-did-fir...sts-emerge
INTRO: From Earth's tallest living plants, California's redwoods, to the planet's largest tropical rainforest, the Amazon, stately forests may seem timeless. But like every species or ecosystem, they have a birth date. In fact, though plants first arrived on land about 470 million years ago, trees and forests didn't hit the scene until nearly 390 million years ago.
During that interval, plant life slowly evolved genetic precursors needed to produce trees, which then outcompeted other plants, Chris Berry, a paleobotanist at Cardiff University in the United Kingdom, told Live Science.
In 2019, Berry and colleagues reported on the oldest forest on record, in the journal Current Biology. This forest, uncovered in Cairo, New York, revealed that features characteristic of trees and forests — namely wood, roots and leaves amid a population of dozens of plants — appeared "far earlier than previously suspected": in the early Devonian period, 385 million years ago, the researchers said in the study... (MORE - details)