Rebutting assorted criticisms of evolution, especially the human version, is in many respects like playing 'whack-a-mole'. This is on account of the fact ignorant, anti-evolution creationists and intelligent design (ID) fanciers have engineered whole-cloth lies and deceptions about it, e.g.
From:
The Sundry Ways That Anti-Evolutionists Misfire
In the process, they've
roped in millions to believe their insane nonsense of 'Adam & Eve', a 6,000
yr.-old Earth etc. merits being taught alongside evolution. It doesn't: it
merits being put into the nearest dumpster with their other swill.
So in this extensive post, culled from creationist objections I've encountered for over 40 years, I want to highlight some of the most common myths
perpetrated about Darwinian evolution. In many respects I already covered one
several blogs ago, that was concerning the "missing link". So now we
will look at some others.
1. If Evolution’s true then why don’t we see apes evolving into humans?
This myth errs in not recognizing that humans, apes and monkeys are all distant
cousins, as opposed to species in the same SINGLE evolutionary path. Humans
don’t come from apes but from a common ancestor that was neither ape nor human
in the distant past. Also, it overlooks the algorithmic branching basis of
evolution, see e.g.
Thus, multiple evolutionary offshoots (as shown above) confirm no (single)
primate evolution is based on a single path. Thus in the past seven million
years there have evolved multiple hominid species including Homo Habilis, Homo
Erectus, and Homo Neanderthalis- all of which went extinct along the way-
except modern humans or Homo sapiens. Meanwhile the idea of current apes
evolving to humans totally turns this algorithmic-convergence on its head, and
proposes a singly determined evolutionary path!
Less well known is the crucial role that dentition analysis and tool making
play in sorting the fossils of prehistoric humans. For example, one of the
first questions the investigator will ask is whether a given jaw and teeth
found in it, can accommodate flesh eating. For some fortunate cases, this is
also answered by the fossils found in the vicinity of the hominid ones. For
example, in the case of one Au. garhi fossil (see image of this hominid) an
antelope jawbone was found nearby and on it ancient cut marks disclosing its
tongue had been sliced out using a stone tool. Radio-nuclide dating of both
fossils traced them to the same time.
Obviously, genetic testing is the optimum or gold standard. In one of the most
powerful ever demonstrations of the validity of human evolution, Yunis and
Prakash, 1982, Science, Vol. 215, p. 1525, 'The Origin of
Man: A Chromosomal Pictorial Legacy', showed that the human chromosome designated
'2' was the result of the telomeric fusion of the two ape chromosomes, 2p and
2q. The effect also saw the reduction from 24 chromosome pairs in apes, to 23
pairs in humans. In other words, the duo of ape chromosomes (2p and 2q) can be
considered prima facie evidence that humans and apes share a common descent.
2. No one’s ever actually seen evolution occur!
In fact, we do observe evolution happening especially with organisms (e.g.
fruit flies, viruses, bacteria) that possess short reproductive cycles. The
problem arises because creationists treat micro-evolution disparately from
macro-evolution. Because they don't regard the former as part of a continuum
leading to the latter, they consider "macro-evolution" the only
genuine form. (By “micro-evolution” we mean minute evolutionary change,
involving a small proportion of DNA. For example, the emergence of an
orange-eyed fruit fly (drosophilia melanogaster) after 20 generations would
demonstrate microevolution.)
Macro-evolution entails a proportionately large change in the DNA underlying it
that probably reflects ongoing natural selection, over significant time. For
example, the change from a cold-blooded dinosaur to a warm-blooded dinosaur
that’s a precursor of modern birds would be a case of macroevolution.
The point missed by the Creationists (or perhaps they never processed it in the
first place) is that it is hundreds (or thousands) of micro-evolution
transitional components that engender macroevolution, whereas creationists
think they are two totally distinct aspects that are unrelated. Once one
accepts the two are integrated into one interwoven process then one can accept
that we DO see evolution actually occurring as when fruit flies have altered
their wing shape or eye color after 20 generations!
Once more, the key aspect that shows micro-evolution is real evolution is the
fact that gene frequencies are observed to change (along with the fitness) as
time goes on. Thus, it is not simply like "breeding cattle" or
different species of dogs (for which many varieties may actually see the gene
frequency alter in negative directions, with fitness reduced).
To fix ideas: gene frequencies help determine the success (and progress)
of natural selection. In natural
selection there is a genetic "favoritism", as it were, for
certain species' traits or characteristics to be passed on or selected out of a
group of competing traits in the gene pool. In more technical terms,
preferential alleles appear by virtue of their relative increase in gene
frequency.
Two quantitative measures for success of
natural selection are the fitness (w) and the selective value (s): These can be
measured on either absolute or relative scales, but are related algebraically
on the latter by:
w = 1 – s, or s = 1 – w
As an illustration, consider a cockroach
species (Blattella germanica) with allele D, where D denotes resistance
to the pesticide dieldrin, and d denotes non-resistance. In the population
after some defined time, let three genotypes be exhibited in the population:
DD, Dd and dd. Now, on average over time let each dd and Dd
individual produce one offspring, and each DD produce two. These average
numbers can be used to indicate the genotype’s absolute fitness and to project
the changes in gene frequency over succeeding generations. The relative fitness
(w) is meanwhile given by: w = 1 for DD
w = 0.5 for Dd
w = 0.5 for dd
The selection values, or relative measures of the reduction of fitness for each
genotype, are given respectively by:
s = 1 – 1 = 0 for DD
s = 1 – 0.5 = 0.5 for Dd
s = 1 – 0.5 = 0.5 for dd
As we expect, the dieldrin-resistant genotype displays zero reduction in
fitness, and hence maximum survival rate. By contrast the d allele can be
regarded as ‘deleterious’. Indeed, it can be shown that over successive
generations of roaches, the gene frequency (of d) will decrease by:
D q= -spq2/(1 - sq2)
Here p is the frequency of the favored allele, and q the frequency of the
disadvantaged (‘deleterious’) allele. Let’s say at a particular time a gene
frequency ‘snapshot’ of the cockroach population under study yields: p(D) =
0.60, q(d) = 0.40, i.e. the favored allele D is reproducing at the ratio 3:2
relative to the disadvantaged one, d. Then one can work out how the
alleles' frequencies vary over multiple generations. Of course, since the
fundies - most of them- can't do simple algebra, this will be beyond them
....so they will never accept it!
3) Evolutionists claim the process occurs by random chance.
Not so. Natural selection is not “random” nor does it operate by “chance”. What
happens is that once a particular mutation is stabilized, then natural
selection preserves the gains and eradicates the mistakes (to enhance better
adaptation). Meanwhile, "chance" would be like me sitting a monkey
down in front of a type writer or computer keyboard and hoping there is some
"chance" it will type out at least one page of coherent script. But
since a monkey will likely not recognize any key - or even if it does, then
make a connection to words, or how to compose them into articulated thoughts -
this isn't likely. It all rests on CHANCE!
Meanwhile, natural selection rests on preferred steps each of which consolidate
former steps while advancing the adaptation. Thus, the eye evolved from a
single light sensitive spot in a cell to the complex organ we behold today not
by chance but rather by thousands of intermediate steps – each preserved
because they assured better adaptation if incorporated, and hence a better eye.
Many of these steps can still be observed today in simpler organisms.
Richard Dawkins perhaps put it best:
"What natural selection does is to consolidate particular random
mutations into a more stable, adaptive adjustment – governed by deterministic
factors and inputs. Thus, that while the selected trait often appears at
random, its preservation in the gene structure cannot be relegated to
randomness”
Again, his distinction between deterministic and random factors and inputs is
perhaps too subtle for creationists and their ilk to comprehend. After all,
most have never taken even a high school biology course, far less a college
level one.
4) The Second Law of Thermodynamics disproves Evolution
This myth commits at least two fundamental errors:
(a) The error which assumes that evolution means more primitive organisms develop into more complex or organized ones, and,
(b) The error that the second law (because it refers to
increasing disorder or "entropy") applies to all living things- hence
it is impossible they can "evolve" to more orderly, organized forms.
Consider (a) first: At no point and no place do evolutionists claim that more
organized forms are the inevitable manifestation of natural selection and
adaptation, and represent evolutionary success.What evolution states,which any
high school biology student learns, is that the species which survive best are
the most well adapted to their environment.
Thus, the humble cockroach beats just about all other species on Earth for
evolutionary success given it's been around for 150 million years. Humans,
though much more complex and organized than cockroaches, have only been around
in their modern form for barely 1.5 million years, if that. Humans, up to now,
have enjoyed barely 1/100 th the evolutionary success of the cockroach,
measured in time!
Now, as to (b), this is a common error of those who've never taken advanced
physics, but just read Googled excerpts. It's basically a direct result of
misinterpretation of the 2nd law, something I often see from those who've never
taken a serious physics course. Strictly speaking, the law states:
Entropy (the state of disorder) will tend to increase
over time in any closed system
This is generally expressed in statistical mechanics terms as:
s = log g
Where 'g' denotes the number of accessible states. In other words, in a closed
system we will expect the probability of increasing entropy and that means
increasing accessible states. This was discussed at length when we looked
at assorted spin systems (see the series on 'Order and disorder' earlier this
month) and noted that higher
entropy - as in a state with
low excess spin- corresponds to the
most probable state. Say
a closed magnetic spin system S(2), has 10 spin ups while S(1) has five,
then S(2) has a much higher degree of order (less entropy) than the system
S(1).
The part about closed systems is very crucial since it is exactly the
part that the creationist-ID crowd omits, which renders their complaints
using the 2nd law non-starters. The reason is that neither the Earth nor
its biological systems are "closed" systems, hence do not exhibit
constantly increasing disorder. The Earth, for example, receives a constant
input of radiant energy from the Sun - quantified as some 1360 joules per
square meter per second. Plants on the Earth are likewise OPEN to solar energy,
and receive it and then use it in the process of photo-synthesis.
Since Earth is an open-dissipative system then at any given time for any
subsystem, entropy may decrease and order increase, thus life may evolve
without violating any natural laws.
Bottom line: so long as the Sun is radiating its energy, life can continue
thriving and evolving. (Thus, more highly organized organisms such as humans
have had the capacity to emerge, by dint of this input energy which they've
been able to consume and retain - if only briefly).
5) Only an Intelligent Designer could have made
something as complex as the eye
Richard Dawkins originally shot this specious reasoning down
when he observed:
"This kind of default reasoning leaves completely open
the possibility that, if the bacterial flagellum is too complex to have
evolved, it might also be too complex to have been created. And indeed, a
moment's thought shows that any God capable of creating a bacterial flagellum
(to say nothing of a universe) would have to be a far more complex, and
therefore a more statistically improbable entity than the bacterial flagellum
(or universe) itself - even more in need of an explanation than the object he
is alleged to have created"
At the very minimum, advocates of such a complex intelligent
designer should at least have provided the necessary and sufficient conditions
by which its design operates, but they haven't even done that.
Secondly, the anatomy of the eye certainly doesn't bespeak
the existence of any kind of intelligent designer, but rather more the outcome
from an algorithmic process. For example, it's built upside down and backwards-
with photons of light having to actually travel through the cornea, lens,
acqueous fluid, blood vessels, ganglion and amacrine cells, horizontal and bipolar
cells, before reaching the light sensitive rods and cones that convert the
light into neural impulses. (Which are then sent to the visual cortex at the
rear of the brain for processing into meaningful patterns).
For optimal vision, why would an intelligent designer have
built an eye upside down and backwards? Further, why on earth create it with a
blind spot? What kind of "intelligent" design is that?
Far from a "designer" being in any way
involved, the human eye betrays the pathways and structures that naturally
would result from an evolutionary dynamic based on natural selection!
6) Too Many Gaps Exist in the Fossil Record for Evolution to
be true.
This is a common myth, but it ignores that fact we have
hundreds of intermediary fossils, such as for Archaeopteryx (one of the
earliest known fossil birds with reptilian skeleton and feathers). We also have
the records for a number of Therapsids, the intermediate species between
reptiles and mammals. We also have the intermediary record for Tiktaalik – an
extinct, lobe-finned fish fitting between fish and amphibians. Not to mention
records to piece together a very coherent picture for the elephant (see diagram)
Further we know (based on fossil evidence) there are at least
six intermediate stages in the evolution of whales and a dozen intermediate
stages since the hominids branched off from the great progenitor common
ancestor apes 6 million years ago.
In any case, as I also showed in many previous blogs, fossil
record evidence does not make up the entire evidentiary constellation for
evolution. We also have genetic evidence for common ancestry, for example of
chimps and humans – as revealed in both having exactly the same
cytochrome-c protein sequence – for which the odds are unfathomably remote (1 in
10 to the 93rd power) to be mere coincidence.
Of course, none of this will make a dime's worth of
difference to fundamentalist creationist, because they don't adhere to
scientific reasoning but only what's in their 2,000+ year old scriptures.
7) Evolution's only a theory and we know theories aren't real
This myth is based on a simple misconception of what constitutes
a theory, actually confusing it with conjecture or speculation. In fact, a
theory is the most advanced articulation of the scientific process: it
represents the phase at which a hypothesis has actually been found to meet its
predictive tests, and been confirmed. Thus, all branches of science are based
on theories. For example, in physics we have the modern quantum theory (which
explains the origin of the spectral lines in atoms, as well as their energy
levels) and the theory of general relativity - which accounts for the action of
gravitational fields near massive objects.
A theory is considered robust and reliable if it consistently
predicts new phenomena that are subsequently observed. Facts then, are the
world's data, and the theory of evolution is replete with them, including: the
fact that humans and chimps display the same cytochrome-c protein sequence, and
the fact that the 2p and 2q chromosomes in apes have undergone telomeric fusion
to become the single '2' chromosome in humans. Thus, theories represent
explanatory ideas about such facts we behold.
Speculations, meanwhile, are nontestable statements that are
not strictly part of science. The "intelligent designer" is such a
speculation until such time the ID backers can come up with not only an
explanation for its nature (especially the necessary and sufficient conditions)
but also describe specific tests by which we may confirm its existence.
Unlike the speculation of the ID, the theory of evolution
meets all the criteria of good science, including:
- It's guided by specific natural laws and principles
- It is explanatory by reference to these self-
same natural laws and principles
- it is testable by way of using those laws and principles -
against the actual patterns, constraints of the empirical world
- It is not only testable but also falsifiable using tests
By contrast, no ID proponent has yet informed us how to
falsify any of his claims, not one! Until he does so, he can't be said to
possess the most remote semblance of a theory. What he is then advocating is a
religious belief.
8) Evolution Can't Account for Morality
In fact, the most recent research into primates shows that
morality of a sort isn't peculiar to humans - as one find self-sacrifice and
sharing behavior in monkeys, as well as in dolphins, gorillas, whales, and
elephants.
As a social primate species, humans also evolved a deeep
sense of right and wrong, probably emerging during the transition from the
hunter-gatherer culture of the Stone Age to the Agricultural milieu. Because
humans in the latter framework depended on reciprocity and cooperation to get
crops harvested and that meant sharing the bounty for all. This stability for
the purpose of shared work also required strict moral codes to preserve the
cohesion of the group and its survival. Thus, certain behaviors such as selfish
hoarding, rape, theft, or wanton aggression were unacceptable. Current evidence
suggests human morality was in place on this basis long before the first
religions appeared.
Thus it was that evolution created the social and moral
sensibilities and emotions that inform us that lying, adultery, murder and
stealing are wrong because they destroy the the trust in human relationships
contingent on truth-telling. No "Ten commandments" was needed.
Nor would it be possible for a social primate species to
survive without some inborn, evolved moral sense. Without that moral sense, for
example, no outrage would be expressed at the rape and torture of others, and
because of this incapacity, the unique cohesion and order binding human
societies would soon be destroyed. Our recognition of the pain and suffering of
others is a direct outgrowth of these evolved moral emotions, not an invented
"god". Especially the one sought out by fundies in their scriptures
who can approve wholesale genocide without batting an eyelash (if he had one!)
Contrary to religious fabrications, it is the evolved moral
and ethical sensibility which enables us to empathize with the suffering of our
fellows while also recognizing that such suffering inflicted by peer aggression
is wrong. We need no god to tell us this, and what religions have done is
merely to appropriate the natural moral sense and smother it with hundreds of
religious platitudes, scriptural mandates and rules. Thus, on the
evolutionary constitution of a moral human nature is built the stable
constitution of human societies. Those which tend to forget that, or allow
temporary tendencies such as greed blind them, will pay the price by not
surviving.
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