The Babylonian and Egyptian “creation” stories both include the idea
of a primordial sea from which the Earth and life arose. These stories
often included the idea of humans being born from a goddess. The primeval
Chaos was a “god” who created people and nature and the other gods.
In most Mediterranean civilizations, the
widely-accepted theory of the universe had the Earth as a flat disk
floating on the world ocean which surrounded it. Below was water
(forever?) and above was sky, the abode of the gods. The land portion
included all that was known at the time, basically an area around the
Mediterranean Sea. “Down” (somewhere under the world ocean?) was the
underworld. What people were able to observe in their daily lives was an
universal frame of reference. Obviously, if the Earth was round, any
people, water, etc. on the bottom would fall off.
The Greek philosophers were perhaps the
first to separate the question of origins from their gods and goddesses.
The Greeks believed that the gods and goddesses, too, were created out of
the primordial substance(s). Greek thought went one step farther. They
thought of air or water as the first cause of all life (both their gods
and humans). These were not an air-god or water-god, and the gods (who
were also created) did not create nature nor humans. The gods and humans
both came from Gaia, mother Earth, who was not one of the gods on
Mt. Olympus, but some sort of a predecessor to everything.
Among the Greek philosopers were:
- Thales (650 - 580 BC) regarded water as
the cause, beginning, and end of all things. His ideas were probably
the beginning of the controversy among the Greek philosophers
regarding the importance of water vs. air vs. fire as the
- Anaximander (611 - 546 BC) is
credited with the first written work on natural science, a classical
poem entitled On Nature. In this poem, he presented what may be
the first written theory of evolution. He wrote that animals
arose from slime which had been evaporated by the sun. He thought that
the first animals lived in the sea and had prickly, scaly coverings.
As these fish-like creatures evolved, they moved onto land, shed their
scaly coverings, and became humans.
- Heraclitus (around the same time) felt
that the universe is continually changing, thus it is senseless to ask
for its origins in the manner of a myth. He taught that there is no
beginning or end, only existence.
- Xenophanes (b. 570 BC) was one of
the first people to observe fossils in rock layers.
Interestingly, he recognized that the rock in which the fossils were
found had at one time been submerged mud. He explained the existance
of fossils by saying that that the world evolved from a mixture of
earth and water, and that the Earth will gradually be re-dissolved. He
believed that the Earth has gone through this cycle several times
leading up to the visible fossils.
- Empedocles (~490 - ~440 BC) tried
to solve the water-earth-fire debate by saying that there were not one
nor two, but four original elements: Earth, Air, Fire, and Water. He
thought that everything else came about through their combination
and/or separation by the two opposite principles of Love and Strife.
- Among the many things for which Plato
(427 - 343 BC) is remembered is his idea that there were two worlds.
He said the world which we see is just an illusion, evil, an imperfect
copy of the real world, transitory, and will decay. The real world
which we cannot see because it’s invisible, is good, perfect,
eternal, and static or unchanging. In the real world, there is
obviously no variation or change, nor need for any, because all the
organisms there are perfect. The variation we see among organisms here
is because they are imperfect copies of the real “types” in the
real world. This “pagan” idea was borrowed and incorporated into
Christian beliefs, and in sharp contrast to the Jewish belief that we
are caretakers of the Earth, has been used to justify our wanton
trashing of the planet (“Who cares, since it’s evil and temporary,
- Aristotle (384 - 322 BC), one of
Plato’s most famous pupils, said that species are fixed in a
hierarchy from simplest to most complex, like rungs on a ladder (the Scala
naturae) with no vacancies, no mobility, and no
change/evolution possible since all the spots were full. Later, these
thoughts were incorporated into Christian views, along with the Hebrew
idea that life is created. This view has dominated Western thought for
about 2000 years.
The Hebrew people lived in between the
Babylonians (Mesopotamians) and the Egyptains, and based much of
their thoughts and knowledge on the influence of their neighbors to either
side. In many respects, their creation story is similar to those of their
neighbors, especially the Babylonians, but their God pre-existed before
was separate from the primeval chaos, and he created both nature and
In more recent times, Georges Buffon
(mid-1700s) was a Frenchman who studied fossils, and was among the
first to suggest the Earth is older than 6000 years.
James Hutton (1726 - 1797) published
a paper in 1795 (which was later refined/modified by Charles Lyell)
in which he said that land forms can be accounted for by current
mechanisms; for example, a gorge was cut by the river running through it,
and was not always there. From this, he drew two conclusions:
Needless to say, this sparked much controversy
because it was a challenge to the prevalent theory on the age of the
Earth, where we came from (a challenge to the Christian Church’s
interpretation of the book of Genesis), etc. This was a major challenge to
the authority of the Christian Church and the beginnings of our modern-day
split between religion and science (objective vs. subjective thought).
- slow, subtle, continuous change over a
long time has a profound effect, and
- if geological change comes from
this slow process, then the Earth is very old, much older than
Archbishop Usher said.
Thomas Malthus (publ 1798), a British sociologist, looked at
conditions in the poor neighborhoods of London. He said that in humans,
the problems of disease, suffering, starvation etc. were a consequence of
the potential for the human population to grow faster than technology
could keep up with. Things like the supplies of food, medical care, etc.
were limited in comparison to the size of the population, thus there was competition
for available resources and only the strong and healthy would survive.
He was, thus, the first to talk about survival of the fittest.
William “Strata” Smith (1769 -
1839), an English surveyor, was the first to scientifically study the
distribution of fossils. He studied the order of rock strata or
layers and noted that the same strata in different areas of England
contained the same fossils. He found he could actually use the fossils in
the various strata as indicators of which rock layer he was examining.
Baptiste Lamarck (publ 1802 or 1809) developed a theory of evolution
in which the main points were:
A number of subsequent attempts were made to
prove or disprove this theory without the benefit of our modern knowledge
of genetics. One experiment involved amputation of mouse tails for
successive generations, showing that even after twenty generations, there
was no effect: baby mice were still born with tails. The Jewish practice
of circumcision was also cited as opposing evidence, since obviously it
had caused no long-lasting change in the population and still needed to be
done to each new boy baby. Lamarck’s theory seemed to make sense in the
light of the then-accepted theory of pangenes coming from the body parts
to make up the homunculus. The classic example he used was giraffes. He
felt that giraffes’ necks got longer because they stretched to reach
higher leaves, and this was passed on to their babies. Another example, to
make the fallacy of his theory more apparent, would be two people who
developed large arm muscles because they were blacksmiths, tennis players,
or weight-lifters having a baby who was born with larger than normal arm
- evolution or change within a species is
driven by an innate, inner striving toward greater perfection,
- use or disuse of various organs made
them larger or smaller, accordingly, and
- these acquired traits could be inherited
or passed on to offspring (inheritance of acquired traits).
Louis Pasteur (publ 1860) disproved
spontaneous generation for smaller organisms (bacteria). Up until this
time, people thought that bacteria and other microscopic organisms could
just come into existance from changes in the external environment.
Pasteur’s experiment with flasks with straight vs. curved (swan-neck)
flasks showed that for bacteria to grow in a sterile medium, their
ancestors must first “fall” into the medium from somewhere else (there
are many bacteria afloat in the air around us).
Charles Darwin published the Origin
of Species in 1859. His theories and where they have led will be
discussed in a subsequent class period.
Alexander Ivanovich Oparin (publ
1936), a Russian scientist, in The Origins of Life, described
hypothetical conditions which he felt would have been necessary for life
to first come into existence on early Earth. He thought the atmosphere was
made largely of methane, ammonia, etc. and that there was much more
volcanic activity and lightening than now. This theory was later tested by
an experiment done by Stanley Miller as a grad student under Harold
Urey in 1953. This experiment will be covered in greater depth in a