Cosmic ancestry
Encyclopedia
Cosmic ancestry is a hypothesis of the origin of life on Earth, based on the panspermia views of Fred Hoyle
and Chandra Wickramasinghe
and further developed by Brig Klyce. It incorporates strong panspermia, the Gaia hypothesis
and the premise that life has no primary origin.
of James Lovelock
.
, nor is it spontaneously generated through abiogenesis
, but that it has always existed in the universe. It claims that the evolutionary progression from simpler to more complex organisms utilises pre-existing genetic information and does not compose this information as it occurs.
According to the theory, higher life forms, including intelligent life, descend ultimately from pre-existing life which was at least as advanced as the descendants. The genetic programs for the evolution of such higher forms may have been delivered to biosphere
s, such as the Earth's, within viruses or bacteria in the same manner as proposed by other versions of panspermia. The genetic programs may then be installed by known gene transfer mechanisms. Also, according to cosmic ancestry, life initiates Gaian processes
that may environmentally alter biospheres.
Cosmic ancestry is opposed to both neo-Darwinism
and Intelligent design
theories. Its assertions require the universe to be ageless.
To these considerations could be added the ontological argument: life, like the rest of the Universe, exists simply because it can. Since this has presumably always been so, it would follow that both are indeed ageless. As Richard Feynman has said, "Anything that is not forbidden [by physical law] is compulsory".
Recent evidence suggests that mechanisms other than random mutation and natural selection could play an important role in evolution - it is now apparent that horizontal gene transfer
is much more widespread than previously thought. There are also many instances of genes detected in species that have no known current use for them. It is claimed that other aspects of evolution which present problems for neo-Darwinism are more easily explained by cosmic ancestry or panspermia, such as life's rapid start on Earth http://www.astrobio.net/news/article2039.html, punctuated equilibrium
and convergent evolution
.
The primary justification for the hypothesis is claimed to be the lack of direct evidence that any natural process can (1) cause life to originate from non-living matter, or (2) compose genetic programs for new evolutionary features. Evidence for speciation, adaptation, variation, and optimization within narrow ranges via natural selection is not disputed.
. Most biologists regard natural selection as an adequate (although not fully understood) and more plausible explanation for the evolution of life on Earth. Some evidence, such as Hoyle's interpretation of his spectral analysis, is widely disputed.
If viruses or bacterial spores had been found on those heavenly bodies we or our machines have visited, the case for cosmic ancestry would be enormously strengthened. But, save a single much publicised but disputed instance of possible Martian origin, they have not.
Fred Hoyle
Sir Fred Hoyle FRS was an English astronomer and mathematician noted primarily for his contribution to the theory of stellar nucleosynthesis and his often controversial stance on other cosmological and scientific matters—in particular his rejection of the "Big Bang" theory, a term originally...
and Chandra Wickramasinghe
Chandra Wickramasinghe
Vidya Jothi Nalin Chandra Wickramasinghe , FIMA, FRAS, FRSA is Professor at Cardiff University and Honorary Professor at the University of Buckingham. He is the Director of the Buckingham Centre for Astrobiology...
and further developed by Brig Klyce. It incorporates strong panspermia, the Gaia hypothesis
Gaia hypothesis
The Gaia hypothesis, also known as Gaia theory or Gaia principle, proposes that all organisms and their inorganic surroundings on Earth are closely integrated to form a single and self-regulating complex system, maintaining the conditions for life on the planet.The scientific investigation of the...
and the premise that life has no primary origin.
History
Hoyle was a long-standing advocate of strong panspermia. He claimed (with Wickramasinghe) that spectral analysis of interstellar dust indicated that large organic molecules and even bacterial spores occur in space. He also viewed natural selection and mutation as too weak a mechanism to drive evolutionary progress. Moreover, his belief in a quasi-steady-state universe allowed him to consider the possibility that life was much older than orthodox cosmology would allow. Whilst Wickramasinghe and Hoyle referred to their ideas as either panspermia or cosmic ancestry http://www.mania.com/48845.html , the latter term has come to be associated with an expanded hypothesis proposed by Klyce, which incorporates the Gaia hypothesisGaia hypothesis
The Gaia hypothesis, also known as Gaia theory or Gaia principle, proposes that all organisms and their inorganic surroundings on Earth are closely integrated to form a single and self-regulating complex system, maintaining the conditions for life on the planet.The scientific investigation of the...
of James Lovelock
James Lovelock
James Lovelock, CH, CBE, FRS is an independent scientist, environmentalist and futurologist who lives in Devon, England. He is best known for proposing the Gaia hypothesis, which postulates that the biosphere is a self-regulating entity with the capacity to keep our planet healthy by controlling...
.
Theory
Cosmic ancestry holds that life is neither the product of supernatural creationIntelligent design
Intelligent design is the proposition that "certain features of the universe and of living things are best explained by an intelligent cause, not an undirected process such as natural selection." It is a form of creationism and a contemporary adaptation of the traditional teleological argument for...
, nor is it spontaneously generated through abiogenesis
Abiogenesis
Abiogenesis or biopoesis is the study of how biological life arises from inorganic matter through natural processes, and the method by which life on Earth arose...
, but that it has always existed in the universe. It claims that the evolutionary progression from simpler to more complex organisms utilises pre-existing genetic information and does not compose this information as it occurs.
According to the theory, higher life forms, including intelligent life, descend ultimately from pre-existing life which was at least as advanced as the descendants. The genetic programs for the evolution of such higher forms may have been delivered to biosphere
Biosphere
The biosphere is the global sum of all ecosystems. It can also be called the zone of life on Earth, a closed and self-regulating system...
s, such as the Earth's, within viruses or bacteria in the same manner as proposed by other versions of panspermia. The genetic programs may then be installed by known gene transfer mechanisms. Also, according to cosmic ancestry, life initiates Gaian processes
Gaia hypothesis
The Gaia hypothesis, also known as Gaia theory or Gaia principle, proposes that all organisms and their inorganic surroundings on Earth are closely integrated to form a single and self-regulating complex system, maintaining the conditions for life on the planet.The scientific investigation of the...
that may environmentally alter biospheres.
Cosmic ancestry is opposed to both neo-Darwinism
Neo-Darwinism
Neo-Darwinism is the 'modern synthesis' of Darwinian evolution through natural selection with Mendelian genetics, the latter being a set of primary tenets specifying that evolution involves the transmission of characteristics from parent to child through the mechanism of genetic transfer, rather...
and Intelligent design
Intelligent design
Intelligent design is the proposition that "certain features of the universe and of living things are best explained by an intelligent cause, not an undirected process such as natural selection." It is a form of creationism and a contemporary adaptation of the traditional teleological argument for...
theories. Its assertions require the universe to be ageless.
To these considerations could be added the ontological argument: life, like the rest of the Universe, exists simply because it can. Since this has presumably always been so, it would follow that both are indeed ageless. As Richard Feynman has said, "Anything that is not forbidden [by physical law] is compulsory".
Evidence
Evidence for the possible astral origin of life is summarised in theoretical panspermia.Recent evidence suggests that mechanisms other than random mutation and natural selection could play an important role in evolution - it is now apparent that horizontal gene transfer
Horizontal gene transfer
Horizontal gene transfer , also lateral gene transfer , is any process in which an organism incorporates genetic material from another organism without being the offspring of that organism...
is much more widespread than previously thought. There are also many instances of genes detected in species that have no known current use for them. It is claimed that other aspects of evolution which present problems for neo-Darwinism are more easily explained by cosmic ancestry or panspermia, such as life's rapid start on Earth http://www.astrobio.net/news/article2039.html, punctuated equilibrium
Punctuated equilibrium
Punctuated equilibrium is a theory in evolutionary biology which proposes that most species will exhibit little net evolutionary change for most of their geological history, remaining in an extended state called stasis...
and convergent evolution
Convergent evolution
Convergent evolution describes the acquisition of the same biological trait in unrelated lineages.The wing is a classic example of convergent evolution in action. Although their last common ancestor did not have wings, both birds and bats do, and are capable of powered flight. The wings are...
.
The primary justification for the hypothesis is claimed to be the lack of direct evidence that any natural process can (1) cause life to originate from non-living matter, or (2) compose genetic programs for new evolutionary features. Evidence for speciation, adaptation, variation, and optimization within narrow ranges via natural selection is not disputed.
Criticisms
Postulating that life (and the universe) have always existed is contrary to nearly all contemporary scientific views. The cosmic ancestry hypothesis has been largely ignored by the scientific community, except for those with a direct interest in astrobiologyAstrobiology
Astrobiology is the study of the origin, evolution, distribution, and future of life in the universe. This interdisciplinary field encompasses the search for habitable environments in our Solar System and habitable planets outside our Solar System, the search for evidence of prebiotic chemistry,...
. Most biologists regard natural selection as an adequate (although not fully understood) and more plausible explanation for the evolution of life on Earth. Some evidence, such as Hoyle's interpretation of his spectral analysis, is widely disputed.
If viruses or bacterial spores had been found on those heavenly bodies we or our machines have visited, the case for cosmic ancestry would be enormously strengthened. But, save a single much publicised but disputed instance of possible Martian origin, they have not.