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XVII International Conference of the European Centre for Science, Arts and Culture
Life in the Universe: a short history of
a big question
Antonio LAZCANO
Miembro de El Colegio Nacional
Universidad Nacional Autónoma de México
Veli Losinj 2017
Life in the Universe
The possibility that other planets were inhabited was
discussed in the past, sometimes in considerable
detail, by naturalists and philosophers alike. The
inventory of names that did so is impressive:
Anaximander, Lucretius, Bruno, Descartes, Huygens,
Herschel, etc.
More often than not, these were speculations that rested
on the idea of a uniform Universe but with little or no
empirical basis.
Despite claims on the contrary, there is little or no
intellectual genealogical continuity of these ideas with
current attempts to study life in the Universe.
Life in the Universe: three major epochs
1. The philosophical attraction of plurality of the
worlds (from Antiquity to the early 19th century)
1. The development of planetology (from 1850 to
1957)
3. Space age exploration (from 1957 onwards)
From the 1850 onwards,
…astronomers, geologists and naturalists start to
discuss the possible links between planetary
environments and hypothetical extraterrestrial
forms of life. The list of names includes several
evolutionists like Robert Chambers, Ernst Haeckel
and Alfred R. Wallace
The attraction of speculation –and the19th century secular faith
in science and technology
In 1899 Ernst Haeckel criticized Flammarion as
“equally distinguished by exuberant imagination and
brilliant style, and by a deplorable lack of critical
judgment and biological knowledge…”. He suggested
that that lower forms of life elsewhere are probably
similar to terrestrial forms, but not the higher forms,
which may not even be vertebrates.
He adds that “perhaps some higher animal stem,
which is superior to the vertebrate in formation, higher
beings have arisen [on other planets] who far
transcend us earthly men in intelligence”
Some evolutionists criticize the speculations by
astronomers on extraterrestrial life.I
19th century scientific developments that
lead to a theory of life in the Universe
1. Development of planetology
2. Birth and development of organic chemistry
3. Development and acceptance of Darwin’s theory
of evolution
4. Recognition of microbes as agents of geological
change
Oparin’s heterotrophic theory and the 1953 Miller-Urey experiment
Science and technology in the Soviet Union
during the Cold War (1957)
First major origin of life/exobiology meetings
1953 Society for Experimental Biology (Cambridge)
1955 Brooklyn Polytechnic (New York City)
1956 New York Academy of Sciences (New York City)
1957 First International Conference (Moscow)
1960 1st. COSPAR Meeting (Nice, France)
1961 2nd COSPAR Meeting (Florence, Italy)
Miller & Lazcano (unpublished)
In July 1958, NASA was created.
Thanks to the efforts first of
Lederberg and then of other life
scientists, the agency stopped
defining life-sciences as merely a
“man in space” program, space
biology as an issue of space
medicine, physiology at high
altitude or contamination.
NASA soon became committed to exobiology, which was seen
as the study the origin, evolution and distribution of life in the
Universe.
Joshua Lederberg
1925-2008
Although his initial concern was the
microbial contamination of the Earth
or other planets, Lederberg was
quick to realize the scientific
potential of a space program. Could
it confirm “the intimate biochemical
information in which we are really
most interested? Can it tell us the
composition of the indigenous amino
acids, or whether the amino acids (if
any) are D- or L-?”
Cf. Wolfe (2002)
“…no one worked harder than Joshua Lederberg to
bring exobiology to the forefront of space policy”
The L factor: a reflection of the Cold War atmosphere
Drake’s equation
N=R* fp ne fl fi fc L
Very rapidly, many astronomers
and physicists began to assume
that N>>1
The life scientists were (and have
remained) much more restrained
“I cannot justify approving
moneys to find out whether or
not there is some microbe on
Mars, when in fact I know
there are rats in Harlem
apartments”
Ed Koch (1969)
Member of the House Committee
on Science and Aeronautics
Not everyone has been equally enthusiastic about
the possibility of extraterrestrial life!
The search for extraterrestial life: high on
speculation and low on fact
1) Diversity and abundance of extraterrestrial organic
compounds;
1) The robustness of abiotic syntheses;
2) Rapid origin of life on Earth;
3) Early Martian conditions conducive to the origin of
life?
4) Many Solar-type stars and extrasolar planetary
systems
The search for intelligent life in the Universe
a) the unwarranted extension of the Mediocrity Principle;
b) the assumption of the universality of progressive
technology;
c) reflection of the Cold War atmosphere;
d) an utopian, escapist solution for environmental and health
issues (including immortality!);
e) an anthropomorfism-tainted vision of cosmic evolution;
f) SETI’s religious overtones (SETI as deities for atheists)
Basalla (2006) Civilized Life in the Universe (Oxford University Press, New York)
Lazcano (2012) Nature 488: 160
Morange (2007) J. Biosci. 32: 1083
Shermer (2001) The Borderlands of Science (Oxford University Press, New York )
Ward & Brownlee (2000) Rare Earth: why complex life is uncommon in the Universe (Copernicus, New York)
Wolfe (2002) Isis 93: 183
A major misunderstanding: evolution as progress
Chaisson 2009, in Dick 2012
“The evolution of complexity and the unity of cosmic evolution”
Evolutionary biologists: the harshest and most
articulate critics of SETI/CETI
George Gaylord Simpson
Ernst Mayr
Lynn Margulis
Theodore Dobzhansky
Biological evolution does not follows a
teleologicaly predetermined path
Microbiology comes of age
a) The prokaryotic fossil record exhibits an
absolute continuity since early Precambrian
times; and
b) The role of prokaryotes as major agents of
geochemical change is now recognized in
full.
Microbial metabolisms have modified the
terrestrial atmosphere and sediments
Alexandr P. Vinogradov
1895-1975
Victor M. Goldschmidt
1888-1947
Vladimir I. Vernadsky
1863-1945
Shifting goals
Much to the dismay of the followers of the idea of
advanced extraterrestrial civilizations, many are now
more interested in the search for extraterrestrial
microbial biological activity.
This has led to valuable multidisciplinary approaches
that are promoting a better understanding of the role
of the biosphere in the evolution of the atmosphere.
It has also given an important boost to fields like
biogeochemistry and to the teaching of evolution in
the USA!
Determinism, teleology and the role of
historical contingency
In spite of the many unknowns that plague our
understanding of the origin and evolution of life, we do
not consider them as the result of inscrutable events;
rather, they are seen as natural outcomes of evolutionary
processes.
However, this does not mean that the emergence of life
is inevitable and that its evolution must follow a
teleological predetermined path. The acknowledgement
of the role of historical contingency is key in the
construction of evolutionary narratives.
We do not know how the transition to
an RNA World took place
Schwartz, 2017 OLEB
“…the contradictions that characterized
early American exobiology are typical for a
period in which the boundaries between
civilian and military interests were blurred
almost beyond recognition.”
Cf. Wolfe, A.J. (2002) Germs in Space: Joshua
Lederberg, exobiology and the public imagination,
1958-1964. Isis 93: 183
Percival Lowell: a compassionate promoter of the
technological feats of a dying civilization
In 1907 Alfred Russel Wallace published a small
book titled Is Mars habitable?, detailing why
animals could not flourish in the Martian habitat
and criticizing Percival Lowell’s description of the
planet as inhabited by a dying civilization capable
of major engineering feats.
Some evolutionists criticize the speculations by
astronomers on extraterrestrial life. II