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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