Abiogenesis

origin of lifeorigins of lifeformationoriginprebioticprebiotic chemistryemergence of lifespontaneous generationprimordial seachemical evolution
Abiogenesis, or informally the origin of life, is the natural process by which life has arisen from non-living matter, such as simple organic compounds.wikipedia
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Astrobiology

astrobiologistexobiologyastrobiological
Researchers study abiogenesis through a combination of molecular biology, paleontology, astrobiology, oceanography, biophysics, geochemistry and biochemistry, and aim to determine how pre-life chemical reactions gave rise to life.
Astrobiology, formerly known as exobiology, is an interdisciplinary scientific field concerned with the origins, early evolution, distribution, and future of life in the universe.

Life

livinglife on Earthbiota
Abiogenesis, or informally the origin of life, is the natural process by which life has arisen from non-living matter, such as simple organic compounds.
Abiogenesis is the natural process of life arising from non-living matter, such as simple organic compounds.

Miller–Urey experiment

Miller-Urey experimentMiller-Ureydevelopment of organic life from non-living matter
The classic 1952 Miller–Urey experiment and similar research demonstrated that most amino acids, the chemical constituents of the proteins used in all living organisms, can be synthesized from inorganic compounds under conditions intended to replicate those of the early Earth.
The Miller–Urey experiment (or Miller experiment) was a chemical experiment that simulated the conditions thought (1952) at the time to be present on the early Earth, and tested the chemical origin of life under those conditions.

History of Earth

Earth's historyhistory of the EarthEarth history
The classic 1952 Miller–Urey experiment and similar research demonstrated that most amino acids, the chemical constituents of the proteins used in all living organisms, can be synthesized from inorganic compounds under conditions intended to replicate those of the early Earth.
The following Archean and Proterozoic eons produced the beginnings of life on Earth and its earliest evolution.

Biology

biologicalBiological Sciencesbiologist
The study of abiogenesis can be geophysical, chemical, or biological, with more recent approaches attempting a synthesis of all three, as life arose under conditions that are strikingly different from those on Earth today.
Sub-disciplines of biology are defined by the research methods employed and the kind of system studied: theoretical biology uses mathematical methods to formulate quantitative models while experimental biology performs empirical experiments to test the validity of proposed theories and understand the mechanisms underlying life and how it appeared and evolved from non-living matter about 4 billion years ago through a gradual increase in the complexity of the system.

Earliest known life forms

earliest known lifeearliest evidenceearly life on Earth
Earth remains the only place in the universe known to harbour life, and fossil evidence from the Earth informs most studies of abiogenesis.
The earliest time that life forms first appeared on Earth is at least 3.77 billion years ago, possibly as early as 4.28 billion years, or even 4.5 billion years; not long after the oceans formed 4.41 billion years ago, and after the formation of the Earth 4.54 billion years ago.

Eoarchean

approximately 3.7 billion years agoEarly ArcheanEoarchean Era
The age of the Earth is about 4.54 billion years; the earliest undisputed evidence of life on Earth dates from at least 3.5 billion years ago, and possibly as early as the Eoarchean Era (between 3.6 and 4.0 billion years ago), after geological crust started to solidify following the molten Hadean Eon.
The beginnings of life on Earth have been dated to this era and evidence of cyanobacteria date to 3500 Mya, just outside this era.

Carbon

Ccarbonaceouscarbon atom
Life functions through the specialized chemistry of carbon and water and builds largely upon four key families of chemicals: lipids (fatty cell walls), carbohydrates (sugars, cellulose), amino acids (protein metabolism), and nucleic acids (self-replicating DNA and RNA).
These compounds figure in the PAH world hypothesis where they are hypothesized to have a role in abiogenesis and formation of life.

Isua Greenstone Belt

IsuaIsua supracrustal beltIsua district
Evidence of early life in rocks from Akilia Island, near the Isua supracrustal belt in southwestern Greenland, dating to 3.7 billion years ago have shown biogenic carbon isotopes.
If confirmed, the discovery of complex stromatolite structures at Isua so early in the history of the Earth would suggest that life first evolved on Earth over 4 billion years ago.

RNA world

RNA world hypothesisorganisms based on RNAancestral world of RNA
Researchers generally think that current life descends from an RNA world, although other self-replicating molecules may have preceded RNA.
One of the challenges in studying abiogenesis is that the system of reproduction and metabolism utilized by all extant life involves three distinct types of interdependent macromolecules (DNA, RNA, and protein).

Bacteria

bacteriumbacterialEubacteria
The most commonly accepted location of the root of the tree of life is between a monophyletic domain Bacteria and a clade formed by Archaea and Eukaryota of what is referred to as the "traditional tree of life" based on several molecular studies starting with C. Woese.
The ancestors of modern bacteria were unicellular microorganisms that were the first forms of life to appear on Earth, about 4 billion years ago.

Ribozyme

ribozymescatalytic properties of RNAcatalytic RNA
More recently, Peter Ward has proposed an alternative view which is rooted in abiotic RNA synthesis which becomes enclosed within a capsule and then creates RNA ribozyme replicates.
Investigators studying the origin of life have produced ribozymes in the laboratory that are capable of catalyzing their own synthesis from activated monomers under very specific conditions, such as an RNA polymerase ribozyme.

Drake equation

Green Bank equationSagan equationDrake's Equation
Astronomer Jill Tarter, of the SETI Institute, said that the factors of the Drake equation (which estimates the possibility of communicating with other [technically intelligent] life) are a means of organizing our lack of knowledge.
What the equation and the search for life has done is focus science on some of the other questions about life in the universe, specifically abiogenesis, the development of multi-cellular life and the development of intelligence itself.

Impact event

impactmeteorite impactasteroid impact
Based on numerous observations and studies of the geological time-scale, the Hadean Earth is thought to have had a secondary atmosphere, formed through degassing of the rocks that accumulated from planetesimal impactors.
Impact events earlier in the history of Earth have been credited with creative as well as destructive events; it has been proposed that impacting comets delivered the Earth's water, and some have suggested that the origins of life may have been influenced by impacting objects by bringing organic chemicals or lifeforms to the Earth's surface, a theory known as exogenesis.

Archaea

archaeonarcheaarchaebacteria
The most commonly accepted location of the root of the tree of life is between a monophyletic domain Bacteria and a clade formed by Archaea and Eukaryota of what is referred to as the "traditional tree of life" based on several molecular studies starting with C. Woese.
Scientific evidence suggests that life began on Earth at least 3.5 billion years ago.

Stanley Miller

Stanley L. MillerMiller, Stanley Lloyd
Stanley L. Miller and Harold C. Urey performed an experiment that demonstrated how organic molecules could have spontaneously formed from inorganic precursors under conditions like those posited by the Oparin-Haldane hypothesis.
Stanley Lloyd Miller (March 7, 1930 – May 20, 2007) was an American chemist who made landmark experiments in the origin of life by demonstrating that a wide range of vital organic compounds can be synthesized by fairly simple chemical processes from inorganic substances.

J. B. S. Haldane

J.B.S. HaldaneHaldaneJohn Burdon Sanderson Haldane
His article on abiogenesis in 1929 introduced the "primordial soup theory", and it became the foundation to build physical models for the chemical origin of life.

Alexander Oparin

Aleksandr OparinOparinAlexander Ivanovich Oparin
No new notable research or hypothesis on the subject appeared until 1924, when Alexander Oparin reasoned that atmospheric oxygen prevents the synthesis of certain organic compounds that are necessary building blocks for life.
Alexander Ivanovich Oparin (Александр Иванович Опарин; March 2 1894 – April 21, 1980) was a Soviet biochemist notable for his theories about the origin of life, and for his book The Origin of Life.

Nature

naturalnatural worldmaterial world
Abiogenesis, or informally the origin of life, is the natural process by which life has arisen from non-living matter, such as simple organic compounds.
The origin of life on Earth is not well understood, but it is known to have occurred at least 3.5 billion years ago, during the hadean or archean eons on a primordial Earth that had a substantially different environment than is found at present.

Protocell

early evolutionevolvedprotocells
No one has yet synthesized a "protocell" using simple components with the necessary properties of life (the so-called "bottom-up-approach").
A protocell (or protobiont) is a self-organized, endogenously ordered, spherical collection of lipids proposed as a stepping-stone toward the origin of life.

Paleontology

paleontologistpalaeontologistpalaeontology
Researchers study abiogenesis through a combination of molecular biology, paleontology, astrobiology, oceanography, biophysics, geochemistry and biochemistry, and aim to determine how pre-life chemical reactions gave rise to life.
Some scientists have proposed that life on Earth was "seeded" from elsewhere, but most research concentrates on various explanations of how life could have arisen independently on Earth.

Planet Simulator

In October 2018, researchers at McMaster University announced the development of a new technology, called a Planet Simulator, to help study the origin of life on planet Earth and beyond.
The Planet Simulator (also known as a Planetary Simulator) is a machine designed to study the origin of life on planet Earth and beyond.

Meteorite

meteoritesmeteoriticmeteoric
Studies of meteorites suggests that radioactive isotopes such as aluminium-26 with a half-life of 7.17×10 5 (717 thousand) years, and potassium-40 with a half-life of 1.250×10 9 (1.25 billion) years, isotopes mainly produced in supernovae, were much more common.
In November 2019, scientists reported detecting sugar molecules in meteorites for the first time, including ribose, suggesting that chemical processes on asteroids can produce some organic compounds fundamental to life, and supporting the notion of an RNA world prior to a DNA-based origin of life on Earth.

Robert Shapiro (chemist)

Robert Shapiro
He is best known for his work on the origin of life, having written two books on the topic: Origins, a Skeptic’s Guide to the Creation of Life on Earth (1986) and Planetary Dreams (1999).

Earth

Earth's surfaceterrestrialworld
In October 2018, researchers at McMaster University announced the development of a new technology, called a Planet Simulator, to help study the origin of life on planet Earth and beyond.
Within the first billion years of Earth's history, life appeared in the oceans and began to affect the Earth's atmosphere and surface, leading to the proliferation of anaerobic and, later, aerobic organisms.