In this chapter of the essay, I’m going to try to address common arguments against evolution.  A few of these arguments I chose based on previous conversations but in order to make sure that I was fairly seeking out the best, most reasonable arguments against evolution, I posted threads on several forums and on facebook requesting those who don’t believe in evolution to link to or explain their best arguments. Unfortunately I had no takers.  (This probably says more for my poor choice in forums than a lack of available arguments.)  To fill the gaps, I’ve distilled the arguments from the top search results for “arguments against evolution” (avoiding pro-evolution sites that are addressing the arguments).  My attempt in distilling these arguments has been to use a selective filter only so far as to include actual arguments against evolution instead of appeals to scripture.  That said, if I’ve missed any arguments against evolution that seem persuasive to you, please let me know so I can attempt to address them here or admit that I cannot.  If you do propose an argument, though, please be familiar with it yourself – don’t just link me to an endless page of opposition.  Tell me what you think doesn’t make sense.

Scientists can’t agree on or prove how the universe formed.
This is essentially true (though it would be incredibly untrue to say that there isn’t a general consensus regarding the big bang and the expansion of the universe, and it would deceptive not to say that recent study has born out the general theory, though specifics are still being debated).  That said, the argument doesn’t say anything about evolution.  It is a general logical error to say that because the theory of creation contains an origin story for the universe, that evolution must also.  Consider, again, that the Catholic Church embraces both a creator god and evolution.  If, however, you’d like to argue the relative merits of creationism versus the big bang theory, we can address that in a different thread.  If you’d like to read more about the big bang, the following are good places to start: http://en.wikipedia.org/wiki/Big_bang, http://www.talkorigins.org/faqs/astronomy/bigbang.html

Scientists can’t agree on/prove how chemicals became life.
While we’re closer to evolution here because we’re now dealing with life, the theories surrounding abiogenesis also do not speak to evolution.  Again, while creationism addresses the origin of life, evolution does not.  The two theories do not map equally.  If you’d like to read more about abiogenesis, the following are good places to start: http://en.wikipedia.org/wiki/Abiogenesis, http://www.talkorigins.org/faqs/abioprob/

Evolution is statistically impossible.
A common anti-evolution argument is that cellular life is statistically improbable: the chance of all of the proteins necessary even a simple bacterium self-assembling in a single place is so minute as to require an Earth 100 billion years old before we’re even within the realms of possibility; not only that, but if it were statistically possible, why don’t we see life reappearing across earth?  As it’s stated, this objection is actually just a subset of the previous argument about abiogenesis, but the concept is worth dealing with anyway.

Firstly, something does not have to be statistically probable to be true.  If your parents’ gametes could have produced up to 100 million different possible combinations (as we discussed in the first chapter), the chance that you are the one that would result is infinitesimally small – your parents would have had to have had a child every year for 10 million years to even have a 10% chance of producing you.  If there are 10 quadrillion possible viable human genetic combinations (as previously discussed), and about 100 billion humans have lived, the chance of you being produced by any set of parents is roughly 1 in 100,000 – very poor odds indeed.  And yet here you are!

Secondly (and now that I’m done being flippant with statistics), the argument doesn’t take a number of important details into consideration.  Firstly, the case study for the argument – a minimal but modern bacteria called Mycobacterium genetalium which has about 400 different proteins – only needs about 256 of those proteins to survive.  Even that very simple bacterium, though, is on an order of complexity several magnitudes beyond what abiogenetists propose as the first protocells (consider, for example, the difference between viruses and bacteria).  The argument ignores the fact that these 400 proteins are created from peptide building blocks that do self-assemble easily and quickly in laboratory tests do to the chemical properties of the molecules involved, and that only the simplest need have assembled to produce protolife – the more complex proteins build off the others as the protolife becomes more complex.  In other words, the process is not random, any more than coins appearing in the correct slots in a coin sorter is random – conditions can favor certain results (likewise, in my flippant example above, the chance of you being produced by your parents is far greater than the “completely random 1 in 100 million”).

The question about why we don’t see abiogenesis happening frequently today is more subtle.  In response: firstly, conditions were different.  There was little to no molecular oxygen available on the early Earth; oxygen is highly reactive and breaks down unbound complex molecules (in fact, oxygen would have been a potent poison to early life).  Because there wasn’t life on the early earth, there weren’t bacteria just waiting to pounce on complex molecules as they would today – protolife would almost certainly be a favorite foodstuff of cellular creatures that encountered it.  Secondly, it’s not particularly surprising that even under idealized laboratory conditions abiogenesis has not reoccurred – not compared with the billions of years and entire planet worth of chemicals available the first time it happened.  That said, there have been some very promising test results, not just in producing amino acids spontaneously in early earth conditions (the famous Miller-Urey experiment: http://en.wikipedia.org/wiki/Miller%E2%80%93Urey_experiment), but in spontaneous production of RNA: (http://www.wired.com/wiredscience/2009/05/ribonucleotides/, http://en.wikipedia.org/wiki/RNA_world_hypothesis#Support_and_difficulties).

We might argue, too, that even with the building blocks of RNA spontaneously appearing, the chance of useful data appearing in their assembly is as slim as the likelihood that the proverbial room full of monkeys will type out Shakespeare.  However, note (just for example) that of all the possible random combinations of 220 nucleotides, “a staggering 2.5 x 10112 sequences are efficent ligases”.  In other words, the chances are much more similar to a room full of monkeys tapping out recognizable words here and there, and that hardly seems like such an impossibility

I’ve drawn most of the response to this argument from this source: http://www.talkorigins.org/faqs/abioprob/abioprob.html.  I highly recommend reading through the link for more detail.

The law of entropy precludes evolution
This argument is fairly easy to address.  Most of those who employ this argument cite the 2nd law of thermodynamics, which in its oldest, most fundamental form states:
“No process is possible whose sole result is the transfer of heat from a body of lower temperature to a body of higher temperature.”

Of course, what is usually meant is the downstream corollary,
“The entropy of a closed system (such as the universe) tends toward a maximum”.

Problematically for this argument, the Earth is not a closed system.  It is constantly being fed by energy, primarily from the sun, but also from the stars and the constant barrage of meteors and comets and dust.  Feeding energy into a system can produce a variety of results, but one only needs to bake a cake to know that simply “getting hotter” is not the only result.  Chemical changes occur in the presence of heat.  Note, too, that the creation of heavier elements (an increase of energy level and order) depends on the disordered fusion of hydrogen, and that this is going on constantly inside our sun.  Note further the chemists’ corollary to the 2nd law:
“Energetically, the second law of thermodynamics favors the formation of the majority of all known complex and ordered chemical compounds directly from their simpler elements. Thus, contrary to popular opinion, the second law does not dictate the decrease of ordered structure by its predictions. It only demands a “spreading out” of energy when such ordered compounds are formed spontaneously.”

Some may argue that complex chemicals like chlorophyll require life or a “patterning mechanism” to appear, but just like RNA this is untrue – chlorophyll and many other complex chemicals do develop spontaneously in the lab.  Organic processes are just much more efficient, exactly as we would expect.

Further recommended reading (and sources) are here: http://2ndlaw.oxy.edu/evolution.html, http://www.talkorigins.org/faqs/thermo/probability.html, and http://en.wikipedia.org/wiki/2nd_law_of_thermodynamics

Creatures do not gain new genetic information – they do not become more complex, they simply adapt or speciate within their “kind”
In essence, this is an argument that micro-evolution is granted, but macro-evolution is not.  We may see black-caps diverge into two species of bird, or we may see proto-horse become horse, but we don’t see grasshoppers become elephants.  Ignoring for the moment that there is significant evolution between the proto-horse and the horse (and even more so between proto-whale and whale!), and ignoring the fossil record in general, while we have observed “micro-evolution” and speciation (technically, speciation is macro-evolution) we would never expect direct observation of the kind of changes mentioned.  If we saw a frog become a fish over even the course of 200 years, that would be evidence against evolution; it would falsify the predictions evolution makes.  The only way we would expect to see that kind of transitioning between orders and classes is over millions of generatoins (i.e. – in the fossil record) and if the examples provided in previous chapters do not suffice, here is a feast of evidence: http://www.talkorigins.org/faqs/faq-transitional.html

Like begets like, and the vast majority of mutations are not favorable (two-headed calves, mermaid babies, Down syndrome, etc.)
There are several issues complicated together here.  Firstly, the kinds of mutations mentioned above are not the type we’d expect to produce favorable results: firstly, they’re generally major chromosomal problems (like an extra or missing chromosome), not just the addition or modification of a genome.  Secondly, those kinds of significant morphological changes (two heads or conjoined limbs) are too severe to re-enter the breeding pool – both people and animals both who suffer from significantly different appearances or constructions are much less likely to find mating partners.  Much smaller changes (like the ability to process milk, a change in eye or hair or skin color, increased hardiness to cold or heat) are the kinds of mutations we do see happening at the genomic level, and these are likely to persist in the gene pool.

Secondly, the mechanism that allows for speciation requires that breeding pools are separated.  Even if two-headed calves continued to breed normally with other cows, we wouldn’t expect them to speciate unless a particular herd in which two-headed calves appeared was separated from the rest over a very long period and two-headedness offered some advantage.  Among humans there is no separate breeding pool that has existed for any notable period of time (more than 10,000 years or so), so the biggest changes we’re likely to see are minor morphologies like facial structure, eye and hair and skin color, shapes of fingernails, etc.

Thirdly, most mutations are neutral – they aren’t even noticed.  Of the small portion that are noticeable and harmful, they are likely to be removed from the breeding population very quickly (as discussed above).  However, those that are favorable are much more likely to persist.  Therefore even if there are a hundred unfavorable mutations to every favorable mutation, the favorable mutations have a much more significant result over even a handful of generations, since they have the potential to propagate geometrically.

Creatures occurred fully developed in the Cambrian explosion without links to single-celled ancestors.  There is no satisfying link between ape and man.  Etc.
These issues have already been addressed in specific, but this is an opportunity to turn the argument around in general.  How many examples of evolution have to be provided?  Lack of evidence is grounds for lack of belief, but not alone grounds for belief in an alternate theory.  If you accept the evidence for evolution between reptile and bird, between proto-horse and horse, between wasp and bee, but don’t find the evidence for evolution between single-celled organisms and crustaceans convincing, or don’t find the phylogenetics between apes and humans convincing, tell me which is more likely – that evolution occurs in some cases but not in others, or that the particular detail in the overall theory is not adequately evidenced?  I would argue that the evidence in the mentioned cases is extremely compelling, but the point is that the theory of evolution is evidenced with thousands of examples, so does debate surrounding one or two of them (if it cannot be generalized to all of them, that is) shift the preponderance of the evidence?

In order for reptiles to have developed into mammals, we must see things like scales turning into fur, breasts developing from nothing, and external, hard-shelled eggs turning into placental sacs in the womb.
While we might presume that those kinds of things happened, we don’t need to see their development in the fossil record for their development to exist.  As mentioned above, the fossil record will necessarily be incomplete – frustratingly incomplete – and soft tissues that would show these kinds of changes are the least likely to survive in any appreciable way.  That said, while we may not see these particular changes in the fossil record, we may see evidence for their development in the chemical and genealogical history.  For example: Due to their chemical similarity, there is speculation that hair developed not from reptiles’ scales, but from their claws (http://www.msnbc.msn.com/id/27663717/).  There is some evidence that breasts didn’t develop from nothing, but from modified sweat glands (http://en.wikipedia.org/wiki/Mammary_gland#Evolution, http://scienceblogs.com/pharyngula/2006/05/breast_beginnings.php, http://en.wikipedia.org/wiki/Evolution_of_mammals#Milk_production_.28lactation.29).  The evolution of live birth is better understood that the other two developments, but it has also occurred numerous times, even recently (http://news.nationalgeographic.com/news/2010/09/100901-science-animals-evolution-australia-lizard-skink-live-birth-eggs/).

Some complexity is irreducible.  An eye is useless without its component parts.  A bombardier beetle would self-immolate without all features in place.
Irreducible complexity is a fact – there are systems that will lose their function if any one part is removed, but it is not true that examples of these preclude evolution.  Consider possible ways the system could have evolved: deletion of parts, addition of multiple parts, change of function, addition of a second function to a part, or gradual modification of all parts. Additionally, some systems once considered irreducibly complex might not be.  Bacterial flagella were thought to be irreducibly complex, but we are now aware of bacteria with simpler versions of flagella (they are missing “required” component parts) or which use some of the structures in an entirely different, and apparently more primative way – for secretion.

To address the two cases specifically, Darwin’s quote that the evolution of the eye seems “absurd in the highest degree” is generally indicated as proof that it could not have evolved.  What those who quote him fail to mention, though, is that he spent the next three pages explaining exactly the steps that could have produced the evolution of the eye:

  • photosensitive cell
  • aggregates of pigment cells without a nerve
  • an optic nerve surrounded by pigment cells and covered by translucent skin
  • pigment cells forming a small depression
  • pigment cells forming a deeper depression
  • the skin over the depression taking a lens shape
  • muscles allowing the lens to adjust

We know all of these steps are possible because they all exist in animals living today.  We can even break these steps down further into smaller, intermediate steps and still find examples.

In the case of the bombardier beetle, it’s easiest to quote this link (http://www.talkorigins.org/indexcc/CB/CB310.html) whole-cloth:

This is an argument from incredulity. It is based in part on an inaccurate description of how the beetle’s bombardier mechanism works, but even then the argument rests solely on the lack of even looking for evidence. In fact, an evolutionary pathway that accounts for the bombardier beetle is not hard to come up with (Isaak 1997). One plausible sequence (much abbreviated) is thus:

  1. Insects produce quinones for tanning their cuticle. Quinones make them distasteful, so the insects evolve to produce more of them and to produce other defensive chemicals, including hydroquinones.
  2. The insects evolve depressions for storing quinones and muscles for ejecting them onto their surface when threatened with being eaten. The depression becomes a reservoir with secretory glands supplying hydroquinones into it. This configuration exists in many beetles, including close relatives of bombardier beetles (Forsyth 1970).
  3. Hydrogen peroxide becomes mixed with the hydroquinones. Catalases and peroxidases appear along the output passage of the reservoir, ensuring that more quinones appear in the exuded product.
  4. More catalases and peroxidases are produced, generating oxygen and producing a foamy discharge, as in the bombardier beetle Metrius contractus (Eisner et al. 2000).
  5. As the output passage becomes a hardened reaction chamber, still more catalases and peroxidases are produced, gradually becoming today’s bombardier beetles.

All of the steps are small or can be easily broken down into smaller ones, and all are probably selectively advantageous. Several of the intermediate stages are known to be viable by the fact that they exist in other living species.

If we evolved from monkeys, why are there still monkeys?
This argument is, on the face of it, silly enough to dismiss.  Monkeys exist for the same reasons that your cousins exist – the fact that you were born does not preclude the existence of your parents or any of your relatives.  Monkeys did not “turn into” humans any more than your parents turned into you.

However, there is a more subtle reading: wouldn’t evolution predict that the environmental forces that favored humans over their ancestors would have eliminated those ancestors?  In fact, they did.  No one proposes that humans came directly from chimpanzees, bonobos, rhesus monkeys, or any living species of primate – we are their distant cousins, more distant to some than others.  We have a common ancestral species somewhere along the way, and that species is in fact extinct.  When you read this question as “If we evolved from proto-humans, why are there still proto-humans”, we see that the obvious answer is that there aren’t.  The species from which we evolved (discussed in a previous chapter) is extinct, and in at least the case of Neanderthal (a cousin,not an ancestor), we likely got rid of them either through too much war or too much loving – killing them off or interbreeding and absorbing them into our species.  (Recall that closely related species, like wolf and coyote or lion and tiger can regularly produce viable hybrids.)

Evolution is not happening now.  We don’t see transitional forms or new species appearing.
Evolution clearly is happening now, and we do see new species appearing – examples were given in previous chapters.  To deny this you must redefine what “species” means.  All we see are transitional forms – every species is either transitional or heading to a dead end.  The reason we don’t notice this is because we don’t know what to expect of species in a few million years – if we did, we’d certainly note that our contemporary species were “transitional”, just like we do when comparing species that lived several million years ago to those that are modern.

Various quotes by famous scientists.
To treat them fairly, each quote has to be handled individually.  Some are taken out of context (like Darwin’s remark about the eye), and some represent a poor understanding on the part of the scientist (like Hoyle’s remark about the probability of evolution).  In all cases, though, an individual’s opinion is just that.  It’s not evidence.  When that individual publishes a paper with evidence backing up their opinion, it become evidence for or against the theory.  Even if Darwin  had recanted on his deathbed (he didn’t – http://www.talkorigins.org/indexcc/CG/CG001.html), it would not affect in any way the body of evidence gathered in the hundred and fifty years since.

While my interest in your arguments still stands, if you have a real interest in more substantial critique of most creationist/anti-evolutionary objections, this site is encyclopediac: http://www.talkorigins.org/indexcc/list.html

 

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