All posts tagged: origins of life

How a radical new view of life could reveal its origin – and aliens

How a radical new view of life could reveal its origin – and aliens

Published by skeptic

Wherever you are reading this, look around you. Every living thing you can see – other people, pets, birds flying past, trees, flowers, mushrooms, fish – is here because of unions between different species. Classic cases are lichens (typically formed of algae and fungi) or corals (made of algae and animal components), but these examples underplay just how far and deep symbiosis goes. In my new book Togetherness, I make the case that symbiosis – which means “living together” – has been neglected in our explanation of biology and ecology. It’s not just that I think it’s a shame that its significance has been unappreciated; it’s that recognising symbiosis is vital to help us understand who we are and how we came to be. Complex life – all those things you see around you – exists only because of a deep form of cellular symbiosis, and all plants rely on symbiosis to grow and to produce all the food we eat. But this isn’t widely recognised. Since before Charles Darwin published his theory of evolution, and even …

RNA strand that can almost self-replicate may be key to life’s origins

RNA strand that can almost self-replicate may be key to life’s origins

Published by skeptic

Artist’s depiction of QT45 (based on AlphaFold3 prediction) overlayed on a microscopy image of the frozen environment that aids RNA replication Elfy Chiang, microscopy image by James Attwater According to the RNA world hypothesis, life began when RNA molecules evolved the ability to make more copies of themselves. Now we have discovered an RNA molecule that is almost capable of this – it can carry out the key steps involved, just not all at once. “It’s been a long quest to get to the point where you can convince yourself that RNA has the capacity to make itself under the right conditions. I think this shows that it is possible,” says Philipp Holliger at the MRC Laboratory of Molecular Biology in Cambridge, UK. In living cells, proteins carry out key tasks such as catalysing chemical reactions, and the recipes for making them are stored in double-stranded DNA molecules. RNA is a chemical cousin of DNA that usually exists in the form of single strands. It isn’t as good for storing information as DNA because it …

How teaching molecules to think is revealing what a ‘mind’ really is

How teaching molecules to think is revealing what a ‘mind’ really is

Published by skeptic

We all struggle with self-control sometimes. We tell ourselves only one more piece of chocolate, one more glass of wine, one more episode of a binge-worthy series before bed, but then carry on regardless. But who, or what, even is this “self” engaging in this push and pull, before giving in to temptation? The cells in our gut somehow collaborate with those in our brain and hands to reach for the chocolate bar, the wine bottle or the “next episode” button. And, with ever-increasing complexity, at some point a line is crossed, and the whole becomes more than the sum of its parts. That is to say, a self – the entity which acts in the world in ways that serve your goals and desires – emerges.  What if, though, “selves” are present in those very cells, ahead of the point at which they merge to form a greater whole? It might sound outlandish, but biological simulations are indicating that those minuscule units of life, which we usually think about as passive machines – cogs blindly …

Comet 3I/ATLAS from beyond solar system carries key molecule for life

Comet 3I/ATLAS from beyond solar system carries key molecule for life

Published by skeptic

Comet 3I/ATLAS is only the third known visitor to our solar system from elsewhere International Gemini Observatory/NOIRLab/NSF/AURA/Shadow the Scientist; J. Miller & M. Rodriguez (Intl Gemini Observatory/NSF NOIRLab), T.A. Rector (University of Alaska Anchorage/NSF NOIRLab), M. Zamani (NSF NOIRLab) The interstellar comet 3I/ATLAS is belching out carbon-rich chemical compounds at higher rates than almost any other comet in our solar system. One of these compounds is methanol, a key ingredient in prebiotic chemistry that hasn’t been seen in other interstellar objects. 3I/ATLAS, which is only the third visitor to our solar system from elsewhere in the galaxy, appears to be quite unlike any comet from our own galactic neighbourhood. As it travelled towards the sun, an envelope of water vapour and gas rapidly grew around it, which also contained much greater amounts of carbon dioxide than we see in typical solar system comets. The comet’s light also appeared to be much redder than is typical, indicating a possible unusual surface chemistry, and it began releasing its gases while relatively far away from the sun, an …

A sinister, deadly brain protein could reveal the origins of all life

A sinister, deadly brain protein could reveal the origins of all life

Published by skeptic

In 1944, Erwin Schrödinger published a book called What Is Life?. The physicist, famous for his alive-and-dead cat, clearly relished a brainteaser. Today, there is still no good definition. Life is generally agreed to require a minimum of two things: metabolism and reproduction. But the question of how chemistry morphed into biology billions of years ago is very much open to debate. Now, a surprising contender has emerged as the catalyst for sparking the first life – and it is one we typically associate with deadly diseases. Advances in molecular genetics have revealed that all living things on Earth are descended from a single organism dubbed the last universal common ancestor, or LUCA, which emerged around 4 billion years ago. We also know that our planet is approximately 4.5 billion years old. During those first half a billion years, simple, then more complicated, organic molecules were spontaneously synthesised and assembled in larger complexes, eventually evolving into the primitive, single-celled LUCA. How did that happen? Biologists have long debated which key molecule of life came first. …