Millions of years before the asteroid impact that ended the reign of the dinosaurs, mammals were already beginning to shift from tree-dwelling to ground-based lifestyles.
A groundbreaking study uncovered this evolutionary trend by analyzing tiny limb bone fragments from marsupials and placental mammals in Western North America. These subtle fossil clues reveal that mammals may have been responding to a changing world, especially the spread of flowering plants that transformed habitats on the ground. Surprisingly, this terrestrial transition appears to have played a bigger role in mammalian evolution than direct interactions with dinosaurs.
More mammals were living on the ground several million years before the mass extinction event that wiped out the dinosaurs, new research led by the University of Bristol has revealed.
The study, published in the journal Palaeontology, provides fresh evidence that many mammals were already shifting toward a more ground-based lifestyle leading up to the asteroid’s impact.
By analyzing small-fossilized bone fragments, specifically end of limb bones, from marsupial and placental mammals found in Western North America—the only place with a well-preserved terrestrial fossil record from this time—the team discovered signs that these mammals were adapting to life on the ground. End of limb bones were analyzed as they bear signatures of locomotory habit that can be statistically compared with modern mammals.
Please join my mailing list here 👉 https://briankeating.com/list to win a meteorite 💥 Sabine (@SabineHossenfelder) argues that superdeterminism eliminates free will, challenging the idea of causal choice and possibly undermining science if the laws of physics govern all phenomena. However, inspired by daily life experiences in Southern California, I present a defense of indeterminism, countering the claim that everything is predetermined, while also exploring the ideas of cosmologists Raphael Bousso and Alan Guth.
Sabine Hossenfelder, a theoretical physicist, has argued in favor of superdeterminism, a theory that suggests the universe is deterministic and that our choices are predetermined.
According to her, the apparent randomness in quantum mechanics is an illusion, and the universe is actually a predetermined, clockwork-like system. She claims that if we knew enough about the initial conditions of the universe, we could predict every event, including human decisions.
Hossenfelder’s argument relies on the idea that the randomness in quantum mechanics is not fundamental, but rather a result of our lack of knowledge about the underlying variables. She suggests that if we could access these “hidden variables,” we would find that the universe is deterministic. However, this argument is flawed.
For example, consider the double-slit experiment, where particles passing through two slits create an interference pattern on a screen. Hossenfelder would argue that the particles’ behavior is predetermined, and that the apparent randomness is due to our lack of knowledge about the initial conditions. However, this ignores the fact that the act of observation itself can change the outcome of the experiment, a phenomenon known as wave function collapse.
In 1989, political scientist Francis Fukuyama predicted we were approaching the end of history. He meant that similar liberal democratic values were taking hold in societies around the world. How wrong could he have been? Democracy today is clearly on the decline. Despots and autocrats are on the rise.
You might, however, be thinking Fukuyama was right all along. But in a different way. Perhaps we really are approaching the end of history. As in, game over humanity.
Now there are many ways it could all end. A global pandemic. A giant meteor (something perhaps the dinosaurs would appreciate). Climate catastrophe. But one end that is increasingly talked about is artificial intelligence (AI). This is one of those potential disasters that, like climate change, appears to have slowly crept up on us but, many people now fear, might soon take us down.
Interstellar material has been discovered in our solar system, but researchers continue to hunt for where it came from and how it got here. A new study led by Western astrophysicists Cole Gregg and Paul Wiegert recommends Alpha Centauri—the next closest solar system to ours—is a great place to start, highlighting how and why it’s a prime target.
The findings were published March 6 in The Planetary Science Journal.
Interstellar objects are astronomical material, like asteroids or comets, not gravitationally bound to a star. They can come from other solar systems and be thrown into interstellar space by collisions or be slingshotted by a planet or star’s gravity.
Asteroids that orbit close to the Earth inevitably cause us some anxiety due to the even remote possibility of a collision. But their proximity also offers ample opportunities to learn more about the universe. Ryugu, a 900-meter diameter asteroid in the Apollo belt, has recently proven useful in our search for signs of life’s precursors elsewhere in our solar system.
A team of researchers at Kyoto University have found evidence of salt minerals in samples recovered from Ryugu during the initial phase of Japan’s Hayabusa2 mission. The discovery of these deposits, containing sodium carbonate, halite, and sodium sulfates, suggest that liquid saline water once existed within a parent body of Ryugu.
Before examining the samples, the team expected that sample grains returned from the asteroid might contain substances not generally found in meteorites. They anticipated that these could be highly water-soluble materials, which readily react with moisture in Earth’s atmosphere and are difficult to detect unless examined in their pristine state as preserved in the vacuum of space.
2024 YR4 is no longer a danger for Earth, and a (small) chance of a lunar impact could provide great science data.
“We are all rooting for the Moon!” Richard Binzel (MIT) is referring to the asteroid 2024 YR4, which for a few weeks had remained at the second-highest-rated probability of potential Earth impact of any asteroid discovered. Now, although its impact probability has fallen to virtually zero for Earth, it still has a slight chance of impacting the Moon on December 22, 2032.
The year one hundred two thousand twenty-three. A giant meteorite the size of Pluto is approaching the Solar System. It flies straight to Earth. But as the meteorite crosses Saturn’s orbit, a swarm of miner probes approaches it. The scan revealed no minerals on the object, so the searches returned with nothing. Meanwhile, the Space Security Center in Alaska military personnel are setting up a laser. The Solar System witnesses a sudden flare and nothing remains of the dwarf-sized meteorite. Now, unless hydrogen miners on Jupiter post videos of another annihilation on social media… This is what the world will look like when humanity finally becomes a Type Two civilization on the Kardashev scale. We’ll have almost infinite energy reserves, the ability to prepare for interstellar flights, or to instantly destroy any threat. But will humanity really be safe? And what can ruin a Type Two civilization?
The odds of a ‘city-destroying’ asteroid hitting Earth in less than 10 years have risen.
Asteroid 2024 YR4 was found by NASA’s Asteroid Terrestrial-impact Last Alert System and it’s now at the top of NASA’s Sentry Risk Table and European Space Agency’s NEO (near Earth objects) impact Risk List.
For a full breakdown of the implications of the asteroid, head here.
