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Is life better as a dog? A philosopher investigates

New Scientist Feed - Wed, 09/11/2024 - 11:00am
What is it like to be a dog? And what can we learn from them? Mark Rowlands's take, in his book The Happiness of Dogs, is full of insights, finds Abigail Beall
Categories: Science

How Star Trek-style replicators could lead to a food revolution

New Scientist Feed - Wed, 09/11/2024 - 11:00am
Our Future Chronicles column explores an imagined history of inventions and developments yet to come. This time, Rowan Hooper takes us to the early 2030s, when a technological step change enabled us to produce all the food we needed without the use of animals
Categories: Science

Our fascination with monsters tells us a lot about ourselves

New Scientist Feed - Wed, 09/11/2024 - 11:00am
From serpents to zombie pathogens, there is science behind our love of monsters. It reveals a lot about who we are, says Natalie Lawrence
Categories: Science

A riveting exploration of how AI models like ChatGPT changed the world

New Scientist Feed - Wed, 09/11/2024 - 11:00am
Supremacy, a new book from tech journalist Parmy Olson, takes us inside the rise of machine learning and AI, and examines the people behind it
Categories: Science

Why everyone needs to stop joking that they're "a little bit OCD"

New Scientist Feed - Wed, 09/11/2024 - 11:00am
Far from being a behavioural quirk, obsessive-compulsive disorder is a debilitating condition with complex causes that we're just beginning to understand. We should treat it as such, and stop with the misguided quips
Categories: Science

IDF posts video of conditions under which 6 murdered hostages were kept

Why Evolution is True Feed - Wed, 09/11/2024 - 10:45am

In this short video, Rear Admiral Daniel Hagari, chief spokesman for the IDF, shows us the conditions under which the six recently-murdered hostages were kept. (Trigger warning: blood.) For some reason I thought the hostages were being kept either in private residences or in rooms off the tunnels, not in the tunnels themselves. When you realize how many days these hostages have been sequestered by Hamas, even a few days of these conditions seem unbearable.  Clearly the IDF has already done DNA analysis of the blood and will do so on hair from hairbushes.

The conditions under which Israel keeps Palestinian prisoners, including convicted terrorists, are far, far better than the conditions under which Hamas keeps its hostages. Palestinian prisoners in Israel live in sheer luxury compared to what you see below, with food they can cook themselves, fresh air, and good beds.

Remember too that there are still about 60 living hostages in Gaza.  They should be released unconditionally—no deals, no bargaining.  Of course Hamas won’t do it, but in my view making a deal for the hostages by releasing Palestinian terrorists is a bad business.  Right now the world should be baying not for a cease-fire or a deal, but for Hamas to surrender unconditionally and release the hostages, or the IDF has the right to, and will, continue going after the enemy.

Categories: Science

Right versus left: define them (directions, not politics)

Why Evolution is True Feed - Wed, 09/11/2024 - 9:30am

Here is a question that keeps me awake at nights: how do you define right versus left without referring to something, like the placement of our heart, an organ that is already tilted toward one side of the body (the left except in rare cases of situs inversus)?

For example, have a look at a bilaterally symmetrical organism below, in this case one of my favorites (Merriam-Webster defines bilateral symmetry as “symmetry in which similar anatomical parts are arranged on opposite sides of a median axis so that only one plane can divide the individual into essentially identical halves”.) We know left from right because we define them consistently, and that’s because humans are NOT bilaterally symmetrical so we can all agree on which side is which.

But now I’ll ask you to answer this. (i.e., by pointing) Assume you’re talking to a person (a Martian?) who has never heard about right vs. left sides.  Tell them, using the diagram of one of my favorite organisms below, standing upright, which side is the right and which the left without referring to your own body, to any minute differences in the diagram, or to asymmetries in the environment (e.g. the world or the solar system).  Since both sides are identical, how do you know which one is right without referring to how we’ve already defined it, presumably based on our own bodies?  Explain to a Martian who is bilaterally symmetrical which side is its right and which its left, and how they would know it.

Partial image by Charl Hutchings, CC BY 4.0, via Wikimedia Commons

 

I’m not sure if I’m making myself clear here, so I looked in the Oxford English Dictyion for the definition of “right”. There are of course many definitions that don’t refer to the direction, but here’s what it gives for the direction:

a.  of, relating to, situated on, or being the side of the body which is away from the side on which the heart is mostly located b.  located nearer to the right hand than to the left c. located to the right of an observer facing the object specified or directed as the right arm would point when raised out to the side d. located on the right of an observer facing in the same direction as the object specified

This didn’t help, because it all comes down to how humans have defined the sides based on our own asymmetries.

This problem is connected with something that’s always intrigued me: how do directional asymmetries evolve, in which an animals is predictably asymmetrical, like our hearts being more on one side or the others?  (There are some creatures with “fluctuating asymmetry”, in which right is different from left, but it’s not consistent, like lobsters in which one claw is a crusher and the other a slicer, or flatfish that develop to lie randomly on its left or right side sides as adults.  Evolving these doesn’t pose the problem I describe below.)

If we evolved from a bilaterally symmetrical (or radially symmetrical) organism, then even if front and back are genetically specified, as they are, how can you evolve from such a creature into an organism that has features consistently on the right (or left) sides?  The chemical gradients in a bilaterally symmetrical ancestor are presumably the same on both sides, so how can a gene mutation arise that consistently recognizes a given side to give rise to a feature on that side? In other words, how can a mutation KNOW whether it is on the left or right side of the body? (Of course once an initial directional asymmetry has evolved, it creates a directional cue that can be used to evolve further directional asymmetries. It’s the evolution of the first directional feature that is the difficulty.)

I’ve discussed this more clearly in two old posts on this site (here and here), which gives some partial answers residing in how asymmetrical molecules or asymmetrical beating of cilia could lead to the evolution of directional asymmetry from bilateral asymmetry.

But the problem above still nags at me: how do you tell a bilaterally symmetrical Martian which side is right and which is left without referring to our own bodies? Can it be done?

Again, this may be a non-problem, but I’ve seen no definition of “right” or “left” independent of our own bodily asymmetries.

Categories: Science

Genome of Neanderthal fossil reveals lost tribe cut off for millennia

New Scientist Feed - Wed, 09/11/2024 - 9:00am
Analysis of DNA from a Neanderthal fossil found in a French cave indicates that it belonged to a group that was isolated for more than 50,000 years
Categories: Science

Ancient people of Easter Island made return trips to South America

New Scientist Feed - Wed, 09/11/2024 - 9:00am
DNA analysis shows that people from Easter Island had contact with Indigenous Americans around the 1300s, and finds there was no population crash before the arrival of Europeans
Categories: Science

Bubbles of gas 75 times larger than our sun spotted on another star

New Scientist Feed - Wed, 09/11/2024 - 9:00am
Gas bubbles on the surface of a star have been observed for the first time in detail outside our solar system, and they are 75 times the size of our sun
Categories: Science

A fresh understanding of OCD is opening routes to new treatments

New Scientist Feed - Wed, 09/11/2024 - 9:00am
We're finally pinning down the mechanisms that drive obsessive-compulsive disorder, revealing a complex combination of imbalanced brain networks, the immune system and even gut microbes
Categories: Science

Discovery of a new phase of matter in 2D which defies normal statistical mechanics

Matter and energy from Science Daily Feed - Wed, 09/11/2024 - 8:21am
Physicists have created the first two-dimensional version of the Bose glass, a novel phase of matter that challenges statistical mechanics.
Categories: Science

Unique nanodisk pushing photonic research forward

Matter and energy from Science Daily Feed - Wed, 09/11/2024 - 8:21am
Researchers have succeeded in combining two major research fields in photonics by creating a nano-object with unique optical qualities. Since the object is a thousand times thinner than the human hair, yet very powerful, the breakthrough has great potential in the development of efficient and compact nonlinear optical devices.
Categories: Science

Unique nanodisk pushing photonic research forward

Computers and Math from Science Daily Feed - Wed, 09/11/2024 - 8:21am
Researchers have succeeded in combining two major research fields in photonics by creating a nano-object with unique optical qualities. Since the object is a thousand times thinner than the human hair, yet very powerful, the breakthrough has great potential in the development of efficient and compact nonlinear optical devices.
Categories: Science

Advancing power grounding systems: A novel predictive model for soil resistivity

Matter and energy from Science Daily Feed - Wed, 09/11/2024 - 8:20am
For the design of reliable power grounding systems for critical electrical infrastructure, soil resistivity investigation is crucial. However, soil resistivity depends on various geotechnical properties, necessitating the need for robust assessment methods. In a new study, researchers conducted a comprehensive investigation into the behavior and relationships between soil resistivity and key geotechnical parameters and developed a predictive model based on their findings. This model can lead to cost-effective and more reliable design of grounding systems.
Categories: Science

Carbohydrate polymers could be a sweet solution for water purification

Matter and energy from Science Daily Feed - Wed, 09/11/2024 - 8:20am
Water polluted with heavy metals can pose a threat when consumed by humans and aquatic life. Sugar-derived polymers from plants remove these metals but often require other substances to adjust their stability or solubility in water. Now, researchers report a sugar-like polymer that traps heavy metals within insoluble clumps for easy removal. In proof-of-concept tests, the polymer removed ionic cadmium and lead from river water spiked with these persistent contaminants.
Categories: Science

Cooling positronium with lasers

Matter and energy from Science Daily Feed - Wed, 09/11/2024 - 8:20am
Most atoms are made from positively charged protons, neutral neutrons and negatively charged electrons. Positronium is an exotic atom composed of a single negative electron and a positively charged antimatter positron. It is naturally very short-lived, but researchers have now successfully cooled and slowed down samples of positronium using carefully tuned lasers. They hope this research will help others explore exotic forms of matter, and that such research might unlock the secrets of antimatter.
Categories: Science

Astronomers track bubbles on star's surface in most detailed video yet

Space and time from Science Daily Feed - Wed, 09/11/2024 - 8:20am
Astronomers have captured images of a star other than the Sun in enough detail to track the motion of bubbling gas on its surface. The images of the star, R Doradus, were obtained in July and August 2023. They show giant, hot bubbles of gas, 75 times the size of the Sun, appearing on the surface and sinking back into the star's interior faster than expected.
Categories: Science

Brain-wide decision-making dynamics discovered

Computers and Math from Science Daily Feed - Wed, 09/11/2024 - 8:20am
Neuroscientists have revealed how sensory input is transformed into motor action across multiple brain regions in mice. The research shows that decision-making is a global process across the brain that is coordinated by learning. The findings could aid artificial intelligence research by providing insights into how to design more distributed neural networks.
Categories: Science

Researchers combine the power of AI and the connectome to predict brain cell activity

Computers and Math from Science Daily Feed - Wed, 09/11/2024 - 8:16am
With maps of the connections between neurons and artificial intelligence methods, researchers can now do what they never thought possible: predict the activity of individual neurons without making a single measurement in a living brain.
Categories: Science

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