How Did Life Begin on Earth? (3 min)
Kaplan_Universe.mp4
Essential elements of Life
More than 120 molecular species found in giant cloud near Milky Way's center
https://phys.org/news/2026-08-molecular-species-giant-cloud-milky.html
When they surveyed it in detail, they found more than 120
different molecules—including several complex, "prebiotic"
molecules potentially relevant to the origin of life. As the
researchers write in the paper, "This survey has revealed
over 120 molecular species containing all six essential
biogenic elements (C, H, O, N, P and S), including the
aromatic cycle benzonitrile, immediately placing G+0.633
among the richest molecular reservoirs in the galaxy."
Among these findings, three molecules tied to life's basic
chemistry stand out. Ethanolamine, a key building block of
the biological membranes that enclose living cells, was
detected for only the second time in space. Sp-glycolamide, a
structural twin of glycine—the simplest amino acid, which the
body uses to build proteins—also marks a second-ever
detection. And all three versions of cyanomethanimine were
found.
These molecules are thought to be building blocks of adenine,
one of the four genetic "letters" in RNA and DNA. "These
detections, together with the remarkable similarity of the
overall molecular inventory, establish G+0.633 as the first
confirmed astrochemical twin of G+0.693," the researchers
conclude. Therefore, the remarkable chemistry of G+0.693 may
not be a cosmic oddity after all.
RNA Might Have Formed Naturally on Early Earth, Seeding Life
https://www.scientificamerican.com/article/rna-may-be-common-throughout-the-cosmos-new-study-suggests/
New experiments suggest RNA could have formed naturally on
early Earth, potentially seeding life. Researchers recreated
early Earth conditions, showing that RNA-like molecules could
form from a mix of ribose sugar, nucleobases, phosphorus, and
borate, with borate aiding RNA production. While some experts
question the plausibility of this natural process, the
presence of borate on Mars raises the possibility of life
arising independently on other rocky planets.
All life that we have ever observed is based of DNA, RNA,
and Amino acids.
Amino Acids
https://en.wikipedia.org/wiki/Amino_acid
https://en.wikipedia.org/wiki/Essential_amino_acid
Ribonucleic acid (RNA)
Deoxyribonucleic acid (DNA)
Asteroid find upends story of life's origin
https://www.nature.com/articles/d41586-025-00264-3
Fragments collected from the asteroid Bennu contain the
building blocks for life - all five nucleobases that form
DNA and RNA and 14 of the 20 amino acids needed to make
known proteins. But there's a twist: on Earth, amino acids
in living organisms tend to have a 'left-handed' structure.
Those on Bennu, however, contain nearly equal amounts of
these structures and their 'right-handed', mirror-image
forms. This calls into question a hypothesis favoured by
many scientists that asteroids similar to this one might
have seeded life on Earth.
Asteroid Bennu Is Packed with Life's Building Blocks, New
Studies Confirm
https://www.scientificamerican.com/article/nasas-latest-asteroid-sample-hints-at-lifes-extraterrestrial-origins/
NASA's OSIRIS-REx mission retrieved samples from asteroid
Bennu, revealing the presence of organic compounds,
including amino acids and nucleotide bases, suggesting the
early solar system had the building blocks of life. These
findings, along with the presence of water and salts,
indicate a promising environment for life's origins. Further
analysis of the samples and future missions to other
celestial bodies are crucial for understanding the origins
of life and its potential elsewhere in the solar system.
Building blocks of life discovered in Bennu asteroid rewrite
origin story
https://phys.org/news/2026-02-blocks-life-bennu-asteroid-rewrite.html
Amino acids, the building blocks of life, were found in
samples from the Bennu asteroid. Penn State researchers
discovered that these amino acids likely formed in a cold,
radioactive environment in the early solar system,
challenging previous theories of formation in warm water.
This discovery raises new questions about the diversity of
conditions under which amino acids can form and the origins
of life.
Scientists Discover Rain's Key Role Supporting Early Life on Earth
https://www.sciencealert.com/scientists-discover-rains-key-role-supporting-early-life-on-earth
Rainwater may have played a crucial role in stabilizing early
cells, paving the way for life’s complexity. Scientists
propose that rainwater, being a natural source of ion-free
water, could have prevented protocell fusion and RNA leakage,
allowing for stable genetic material and the evolution of
life. This research highlights the importance of
interdisciplinary collaboration in understanding the origins
of life.
Life may have originated in lake environments, where the necessary
chemical reactions for RNA, proteins, and lipids could occur
https://www.sciencealert.com/leading-theory-for-how-life-on-earth-began-is-highly-unlikely-says-contentious-new-paper
Geochemist Benjamin Tutolo argues that the widely accepted
theory of life originating in hydrothermal vents is unlikely
due to outdated assumptions about ancient ocean chemistry. He
suggests that life may have originated in lake environments,
where the necessary chemical reactions for RNA, proteins, and
lipids could occur. This perspective challenges the notion
that hydrothermal vents on other planets are the best places
to search for extraterrestrial life.
Life’s ‘last universal common ancestor’ may predate life itself | Scientific American
https://www.scientificamerican.com/article/lifes-last-universal-common-ancestor-may-predate-life-itself/
Life on Earth began twice (and wasn’t alive)
Researchers have gathered more evidence for the idea that the
first spark that spawned us all — the last universal common
ancestor (LUCA) — was a part-organic, part-rock chemical
system that formed in the energetically and chemically rich
environment of hydrothermal vents. New findings also suggest
that the two oldest single-celled domains of life, bacteria
and archaea, sprang independently from this first source.
How Did the First Cells Arise? With a Little Rain, Study Finds.
https://www.nytimes.com/2024/08/21/science/first-cells-rain.html
https://phys.org/news/2024-08-life-rainwater-protocell-walls.html
https://www.science.org/doi/10.1126/sciadv.adn9657
Abstract
Membraneless coacervate microdroplets have long been
proposed as model protocells as they can grow, divide, and
concentrate RNA by natural partitioning. However, the rapid
exchange of RNA between these compartments, along with their
rapid fusion, both within minutes, means that individual
droplets would be unable to maintain their separate genetic
identities. Hence, Darwinian evolution would not be
possible, and the population would be vulnerable to collapse
due to the rapid spread of parasitic RNAs.
In this study, we show that distilled water, mimicking
rain/freshwater, leads to the formation of electrostatic
crosslinks on the interface of coacervate droplets that not
only suppress droplet fusion indefinitely but also allow the
spatiotemporal compartmentalization of RNA on a timescale of
days depending on the length and structure of RNA. We
suggest that these nonfusing membraneless droplets could
potentially act as protocells with the capacity to evolve
compartmentalized ribozymes in prebiotic environments.
Lab-created ‘protocells’ provide clues to how life arose
https://www.science.org/content/article/lab-created-protocells-provide-clues-how-life-arose
Scientists have created lab-grown protocells using simple
ingredients, providing insights into how early cells formed.
These protocells have double-layered membranes similar to
modern cells and can encapsulate molecules, suggesting they
may mimic a stage in cellular evolution. The researchers
speculate that silica, present on primordial Earth, may have
sparked the formation of early membranes.
How Did Life Get Big and Complex?
https://mailchi.mp/quantamagazine.org/why-colliding-particles-reveal-reality-2493073?e=5edd8f019fv
For most of the history of life, beginning roughly 3.9
billion years ago, there was only one way to be alive: as a
lone cell. The first life forms were, in their entirety,
single, clearly defined microscopic units that reproduced by
dividing into two new cells, each of which went on its way.
Life stayed that way for billions of years. But then some of
these cells started to cooperate. They transitioned from
solo existence into group life. When one cell became two,
they remained together and eventually came to function as a
distinct kind of living assemblage: a multicellular
organism.
Scientists Re-Create the Microbial Dance That Sparked Complex Life
https://www.quantamagazine.org/scientists-re-create-the-microbial-dance-that-sparked-complex-life-20250102/?mc_cid=7ec66366ad
Endosymbiotic relationships between two microbes, with one
living inside the other, underlie cellular complexity across
the tree of life. Until now, no one has observed the opening
choreography of such a partnership’s formation.
Life Requires Energy
Last week we noted that energy is required for complex
molecules to form.
Whether the basic ingredients for life first came from
space or instead formed in a warm soup of earthly chemistry
is still not known. If life DID form on earth, please share
your opinions of what and where energy sources are that
could have contributed to the development of life.
Science News Media
Life on Earth May Have Been Jump-Started by 'Microlightning' | Scientific American
https://www.scientificamerican.com/article/life-on-earth-may-have-been-jump-started-by-microlightning/
New research suggests that water droplets, rather than
lightning, may have catalyzed the formation of organic
molecules on early Earth. The study, led by Richard Zare,
found that the electrical charge difference between water
droplets can generate "microlightning," producing amino acids
and nucleobases. This process, coupled with wet-dry cycles in
rock crevices, could have led to the accumulation of these
molecules, potentially giving rise to the first single-celled
organisms.
The Cosmos Teems with Complex Organic Molecules
https://www.quantamagazine.org/the-cosmos-teems-with-complex-organic-molecules-20241113/
The surprising organic chemistry in interstellar space
https://www.chemistryworld.com/features/the-surprising-organic-chemistry-in-interstellar-space/4019144.article
All of the bases in DNA and RNA have now been found in meteorites
https://www.sciencenews.org/article/all-of-the-bases-in-dna-and-rna-have-now-been-found-in-meteorites
Astronomers Discover Complex Carbon Molecules in Interstellar Space
https://www.sciencealert.com/astronomers-discover-complex-carbon-molecules-in-interstellar-space
First Look at Ryugu Asteroid Sample Reveals it is Organic-Rich
https://www.nasa.gov/centers-and-facilities/goddard/first-look-at-ryugu-asteroid-sample-reveals-it-is-organic-rich/
[2nd] Asteroid Reveals The 5 Key Genetic Ingredients For Life on Earth
https://www.sciencealert.com/asteroid-reveals-the-5-key-genetic-ingredients-for-life-on-earth
Analysis of samples from asteroid Ryugu revealed all five
nucleobases (adenine, cytosine, guanine, thymine, and uracil)
that make up RNA and DNA. This discovery, following a similar
finding on asteroid Bennu, suggests that the building blocks
of life may be common in the Solar System and could have been
delivered to Earth by asteroids. The study also found
variations in nucleobase ratios between asteroids and
meteorites, indicating that the chemical environment within
asteroid parent bodies influences nucleobase formation.
Scientists Discover RNA Component Buried in The Dust of an Asteroid
https://www.sciencealert.com/scientists-discover-rna-component-buried-in-the-dust-of-an-asteroid
https://www.nature.com/articles/s41467-022-29612-x
Never Before Detected – Organic Molecule Essential for Life Found in Interstellar Space
https://scitechdaily.com/never-before-detected-organic-molecule-essential-for-life-found-in-interstellar-space/
https://www.nature.com/articles/s41467-023-36904-3
Scientists Discover How Complex Molecules May Have Stabilized
to Spark Life on Earth
https://www.sciencealert.com/scientists-discover-how-complex-molecules-may-have-stabilized-to-spark-life-on-earth
The Year in Biology (2025)
https://www.quantamagazine.org/the-year-in-biology-20251215/
Latest Science (all sciences)
http://edu-observatory.org/media/Science/index.html
DuckDuckGo
