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Transcript
Icons of Evolution
By Jonathan Wells
Regnery Publishing Co., 2000
Introduction
Does the scientific community have
empirical evidence to support the
theory of evolution?
 Most biological texts answer with a
resounding “Yes.” But is this an
accurate answer?

Steve Badger
2
Introduction
Embryologist Jonathan Wells (PhD in cell
and developmental biology, University of
California, Berkeley) claims that biology
textbooks greatly exaggerate and distort
the evidence to support a theory of
evolution.
 He claims “Students and the public are
being systematically misinformed about the
evidence for evolution” by these books.

Steve Badger
3
Introduction
He uses direct quotes of articles in
peer-reviewed scientific journals,
written by experts in the field to
illustrate these exaggerations,
distortions, and outright deceptions.
 His approach in this book is neither
philosophical nor religious, but it is
scientific.

Steve Badger
4
1. The Miller-Urey Experiment

As a graduate student at the
University of Chicago in 1953, Stanley
Miller and his major professor, Harold
Urey, attempted to simulate the
earth’s primitive atmospheric
conditions in a laboratory apparatus
(see illustration).
Steve Badger
5
1. The Miller-Urey Experiment

They speculated that the primitive
atmosphere had little if any oxygen,
but had methane (CH4), ammonia
(NH3), hydrogen (H2), and water
vapor (H2O).
Steve Badger
6
1. The Miller-Urey Experiment
The mixture was heated, and the
vapors passed through an electric
spark (simulating lightening), and then
cooled and reheated.
 After a period of time, the soup was
analyzed and found to contain amino
acids, the building blocks of proteins.

Steve Badger
7
r
1. The
Miller-Urey
Experiment
Steve Badger
8
1. The Miller-Urey Experiment

This work has been used to support
the idea that life could have arisen
spontaneously from non-life (we call
this spontaneous generation).
Steve Badger
9
1. The Miller-Urey Experiment
Does the Miller-Urey experiment support
spontaneous generation (abiogenesis)?
 Is this really hard, scientific evidence for
spontaneous generation?
 What is wrong with this experiment?

Steve Badger
10
1. The Miller-Urey Experiment
1. The choices of gases to include and
exclude were highly speculative—and
most researchers in that field today
reject them as being unlikely.
 Some evidence suggests that the
primitive earth atmosphere included
oxygen.

Steve Badger
11
1. The Miller-Urey Experiment
2. Proteins as the first organic
molecule is not part of a reasonable
spontaneous generation hypothesis.
Neither is DNA.
 Some suggest RNA is the best
candidate for the original molecule in
spontaneous generation. But we have
thought of no mechanism for
synthesizing RNA—other than by life
forms.

Steve Badger
12
1. The Miller-Urey Experiment
3. The amino acids molecules formed
in this experiment were a mixture of
two forms (they are called D- and L-).
 Life is composed only of the latter.
The presence of the former would
mitigate against spontaneous
generation.

Steve Badger
13
2. Darwin’s Tree of Life
A central feature of almost every
contemporary theory of evolution is that
all life descended from a common
ancestor. Darwin called this “the Great
Tree of Life.”
 This “Great Tree of Life” model predicts:

Steve Badger
14
2. Darwin’s Tree of Life
1. Phylum-level and class-level
differences appeared only after a long
history of changes in species.
2. The fossil record will show evidence
of speciation occurring through all
epochs.
3. The Tree of Life has been used for so
long that many people assume it is
factual.
Steve Badger
15
2. Darwin’s Tree of Life
This theory posits that “phylum-level
differences could not have appeared right
at the start. Yet that is what the fossil
record shows.” (35) We call this “sudden”
appearance of many phyla the Cambrian
explosion, and biologists typically propose
three solutions.
 “So the branching-tree pattern of evolution
is inconsistent with major features of the
fossil and molecular evidence.” (54)

Steve Badger
16
3. Homology in Vertebrate Limbs
Structural similarity is called homology
 Probably the classic examples of
homology are vertebrate forelimbs
(compare the bat’s wings, the
dolphin’s flippers, the dog’s front legs,
and the arms and hands of humans)
 This fact of structural similarity is cited
as evidence of common descent
(evolution)

Steve Badger
17
3. Homology in Vertebrate Limbs

If homology is defined as similarity
due to common descent, how can it be
cited as evidence for common
descent? This is circular reasoning.
Steve Badger
18
3. Homology in Vertebrate Limbs

Scientists have long known that
homologous structures are not
(necessarily) due to similar genes. (If
homologous structures were the result
of common descent, they would be
due to similar genes.)
Steve Badger
19
4. Haeckel’s Embryos

Darwin noticed similarities in embryos
of different species and concluded that
this demonstrates that they descended
from a common ancestor—and what
that ancestor looked like. He relied on
Ernst Haeckel’s drawing of embryos to
illustrate his conclusion.
Steve Badger
20
4. Haeckel’s Embryos

Haeckel’s drawings of embryos of
various vertebrates showed them as
almost identical in the earliest stages,
becoming more dissimilar as they
developed.
Steve Badger
21
4. Haeckel’s Embryos
r
Steve Badger
22
23
Steve Badger
4. Haeckel’s Embryos
r
4. Haeckel’s Embryos


“Ontogeny recapitulates phylogeny,”
they said.
He used the term “ontogeny” to stand
for embryonic development and the
term “phylogeny” to stand for the
evolutionary history of a species.
Steve Badger
24
4. Haeckel’s Embryos
“Biologists have known for over a
century that Haeckel faked his drawings;
vertebrate embryos never look as similar
as he made them out to be.” (82)
 Haeckel’s drawings greatly exaggerated
the similarities and the “evidence [was]
twisted to fit the theory.”

Steve Badger
25
4. Haeckel’s Embryos
“When Haeckel’s embryos are viewed
side-by-side with actual embryos,
there can be no doubt that his
drawing were deliberately distorted to
fit his theory.” (92)
 Even arch-evolutionist Stephen Jay
Gould reached this conclusion (Natural
History March 2000).

Steve Badger
26
4. Haeckel’s Embryos
In reality: vertebrate embryos start out
looking very different, become more
similar in appearance midway through
development, and then become
increasingly dissimilar as they move
toward adulthood.
 Conclusion? “Instead of providing
support for Darwin’s theory, the
embryological evidence presents it with
a paradox.” (99)

Steve Badger
27
5. Archaeopteryx—The Missing Link
Darwin’s theory postulated the existence of
intermediate, transitional links between
extant species and the “parent-species.”
Since the fossil record was incomplete,
none were known when The Origin of the
Species was published in 1859.
 Just a couple of years later, Hermann von
Meyer described a fossil that he named
Archaeopteryx (ancient wing). Another
better specimen was discovered in 1877.

Steve Badger
28
5. Archaeopteryx—The Missing Link

Archaeopteryx had bird-like feathers
and a reptilian jaw and teeth, so it was
hailed as the evolutionary link
between reptiles and birds.
 At last (some thought), empirical,
unimpeachable evidence for the theory
of evolution.
Steve Badger
29
5. Archaeopteryx—The Missing Link


Evolutionists are divided over the use
of Archaeopteryx as a transitional form
Probably the majority of evolutionists
no longer claim Archaeopteryx as a
transitional form
Steve Badger
30
6. Peppered Moths
Peppered moths have two variations:
light and dark (England & USA)
 The ratio of dark to light moths
changed over time
 In the 1950s, Kettlewell suggested
that birds ate the more visible moths

Steve Badger
31
6. Peppered Moths
The light variety were more abundant,
then the dark variety became more
common
 Pollution-darkened tree trunks made
the light variety more visible, so birds
ate more light ones
 An example of protective camouflage?

Steve Badger
32
6. Peppered Moths
Early test seemed to indicate birds ate
more light moths in an environment
with dark trees
 They called it “the most striking
evolutionary change ever actually
witnessed in any organism” (143)
 We have observed an evolutionary
process

Steve Badger
33
6. Peppered Moths
If this selective advantage was real,
the dark moths should have almost
completely replaced the light ones
over time
 Since this did not happen, perhaps
something besides camouflage and
predatory birds was involved

Steve Badger
34
6. Peppered Moths
Peppered moths don’t naturally rest on
tree trunks, but on the underside of
smaller, horizontal limbs
 Many of the photos of peppered moths
on tree trunks were staged
 Textbooks still cite this as evidence of
natural selection

Steve Badger
35
7. Darwin’s Finches
Darwin suggested that the variety of
beaks on finches on the Galápagos
Islands is often cited as an example of
natural selection
 Jonathan Weiner called it “the most
detailed demonstration…of the power
of Darwin’s process” (167)

Steve Badger
36
7. Darwin’s Finches
Steve Badger
37
7. Darwin’s Finches
During the 1970s, research discovered
that beak size in these finches is
related to rainfall and the abundance
of the seed crop
 Finch beak size may fit a natural
selection model, but we have no
empirical evidence to support that

Steve Badger
38
7. Darwin’s Finches
Darwinian theory predicts a diverging
model (greater numbers of varieties in
beak size)
 Observation finds the opposite—a
converging model (fewer numbers of
varieties in beak size)

Steve Badger
39
8. Four-Winged Fruit Flies

Mutations are easily induced in
Drosophila melanogaster
One such mutant has two pairs of
wings rather than one pair
 Does this support the theory of
evolution?

Steve Badger
40
8. Four-Winged Fruit Flies
The extra pair of wings lack muscles
 The flies cannot fly—they are
handicapped
 The extra pair of wings are not
beneficial, they are detrimental

Steve Badger
41
8. Four-Winged Fruit Flies
This extra pair of wings does not
provide evidence that DNA mutations
produce beneficial changes in body
structures
 The mutations were not “natural,” but
“artificial”—under the control of an
intelligent designer (human)

Steve Badger
42
9. Fossil Horses & Directed Evolution
Early in the development of the theory
of evolution, the proposed reconstruction of the evolutionary history of
horses was used to support the idea of
“directed evolution” (orthogenesis).
 Now evolutionists claim that the new
branched-tree theory of horse evolution
argues against directed evolution.

Steve Badger
43
9. Fossil Horses & Directed Evolution
Neither straight-line nor branchingtree models argue for or against
directed evolution.
 Undirected (purely random) evolution
is a philosophical position, not a
scientific observation.

Steve Badger
44
10. From Ape to Human
Evolutionists typically claim that
humans evolved just as the other
animals evolved
 Thus evolutionists typically see
humans as animals that are more
evolved

Steve Badger
45
10. From Ape to Human
The fossil evidence to support models
of human evolution is even more
subjective than that for models of
evolution of other animals
 Much of what is offered as evidence is
actually (speculative) interpretation

Steve Badger
46
10. From Ape to Human
Often the data are merely organized to
fit the model!
 But the data fit other models just as
well!

Steve Badger
47
The point of this book…
Most science textbooks continue to
cite these “icons of evolution” as
evidence to support this theory
 Scientists should know these have
been discredited—many do not
 What does this show about the nature
of the dialogue/argument?

Steve Badger
48