Response to Natural Selection video

I’ve been keeping an eye on some of the Rational Religion articles and videos recently, so here is a quick summary of some of my thoughts on a video about natural selection.
For context: Rational Religion is run out of the UK and is an official Jamaat website (as per their description). My response is not about whether this represents the Jamaat’s official position on evolution, it is just dealing with the subject matter of the article and video.

The video is titled “Why Charles Darwin was WRONG about Natural Selection”. My response is largely to this video, though there is a large overlap between its content and that of this article “Why Natural Selection Cannot Explain Evolution”.  Both the video and article have bold titles, and lay out their intention: they want to disprove natural selection, or at least show that is not responsible for diversity of life. At 1:30 they say “If something has a design, it must have a designer.”
Natural selection is well-established as one of the main mechanisms for evolution to occur (others are genetic drift, migration and bottleneck effect, see this page for details on these concepts). Its importance has been well-known for a long time, and the only debate around it is regarding details of how exactly it works (for example, biologists are still debating rates at which natural selection can help select for certain traits). It is not some obscure new idea that can be debunked with a Youtube video.

By so actively choosing to oppose natural selection, they are siding with the Intelligent Design movement (this  previous article clearly has quotes from ID folks as well as a note of thanks to them at the end). Here is a link showing why the ID movement is unscientific and here are some frequently asked questions about Intelligent Design. 

While they never say this explicitly in the video, the point of “debunking” natural selection for them is to make links to a Creator. If natural selection is a dead process, then you need a way to create traits and life and voila, God can do that! Case closed.
The irony of trying to debunk a robust process rooted in science in order to prove the existence of a creator is not lost on me. The Ahmadi view on evolution till recently has been “guided evolution”, that the processes take place under careful watch of God, so this seems to be a new take on it. 

There are two main points they make in the video:
1) The evolution of complex traits, like eyes and wings, is impossible under natural selection as it requires  a “creative process”. 

In the video they say:

 “So each of those little steps [on the way to building a complex structure]… confers a survival advantage, you still need a sufficiently capable mechanism of explaining the origin of each of those single units of that step within the realms of probability.”

They ask for “a creative process” for the production of these structures. Below I will talk about how some important features in animals today (wings, eyes) formed due to natural selection, without any foresight or “creativity” but simply as a result of what mutations arose in populations of individuals and how those were selected for or against by natural selection.

New traits arise in populations due to mutations. Within a population of organisms, a few may have mutations arise in their DNA, and if these result in a physical change (phenotype), and can be passed onto offspring, then maybe natural selection can act on them. Not every mutation can be passed on, and there has to be a certain number arising within a population before natural selection can act on it. 

The two structures they bring up at different points in the video are the eye and bird wings. At one point, they say “What is half a wing?” in reference to how birds evolved their wings. They assume that bird ancestors had half of a wing and then a full one, even though bird evolution has been studied extensively and a quick Google search will show how some therapod dinosaurs (ancestors of modern birds) had feathers. (Even if birds did have half a wing, it would be more advantageous than no wing at all!) Ask any dinosaur-loving child about Archaeopteryx, and they will tell you about this transitional fossil that was half-dinosaur half-bird and whose front limbs were transitioning into wings. 

I will briefly summarize bird wing evolution, and then eye evolution.  


Archaeopteryx lithographica, found in the Jurassic Solnhofen Limestone of southern Germany.
Bird evogram
Source: https://evolution.berkeley.edu/evolibrary/article/evograms_06

This is a visual showing the evolution of traits which led some dinosaurs on the trajectory to become modern-day birds.  This is based on fossil evidence, as well as DNA work which shows how certain genes in birds reflect the ancestral changes in their bodies. You can see the reduction of digits happening as well as elongation, and loss of two digits. Within large populations of theropod dinosaurs, some of them lost one digit first, then their clavicle bones fused to become one wishbone and their bones slowly became lighter and more hollow. There may have been many environmental pressures that led them to develop air sacs and lighter bones: this article shows dinosaurs had efficient respiratory structures similar to birds perhaps due to an active lifestyle. Individuals within these dinosaur populations that developed these structures would have a massive advantage as they would be able to escape predators and/or catch prey much more efficiently and have a higher rate of survival. 

In addition to the bone structure, feathers are the other crucial component to wings. The earliest feathers were observed on dinosaurs such as Oviraptor, which also reproduced like modern birds by laying eggs in a nest and incubating them. Feathers as a trait were selected for because you have a higher chance of survival and mating if you can stay warm. There is also evidence that the feathers played a role in sexual selection with dinosaurs too, where males with showy feathers had a higher chance of passing on their genes: this creates selection pressure in favour of feathers. The evolution of feathers as well as the modifications to the front limbs of the dinosaurs eventually gave rise to simple wings. 

There are other elements to bird evolution as well, such as beaks and shrinking size. There are some articles included in the reading list that discuss this at length. There is enough evidence to show that bird wings, just like other features, are the result of small mutations that were beneficial in the population and over time were selected for. 

Another contentious point brought up is the evolution of the eye. This is a classic way that intelligent design people have tried to debunk natural selection before, so I was sure that it would come up here too.

All animal eyes have photoreceptors, which have opsin molecules on top of them — when light hits the opsins, it leads to a chain of reactions that send an electrical signal to our brain. All vertebrates have the exact same type of opsin (c-opsin). Insects and other invertebrates have r-opsin instead. The earliest animals had simple eyespots, used to tell light from dark. These light-sensitive areas over time started becoming rounder and moving to sides of the head, later developing a folding to resemble a “cup” which helps direct light coming into the eye. Most likely mutations were causing the eye structure to slowly fold in different directions, and the cup shape was selected for because it helps get light in the eye in the most efficient way. This is essential, because it helps the organism know direction of the light source so they can spot their predators.

Lenses were a crucial need for these eyes so they could form images. Lenses are made of crystallins, transparent proteins that help focus images onto the retina. Vertebrates have alpha-crystallin, and they evolved initially to provide repair: crystallin proteins are one of the most stable ones in our body, and evolved as a heat-shock protein (which protect over-heated proteins in different parts of the body). In one of the early vertebrates a mutation caused the alpha-crystallin to be produced on the surface of the eye,  and it also happened to be a good way to bend light and form images. Many consecutive mutations fine-tuned this process to make it better at bending light. The slightest mutation that improves eyesight will be selected for, because it gives the animal a major advantage over others. 

The point of including this jargon is to show that eye evolution is extensively studied by evolutionary biologists. The evolution of the eye, or of bird wings, is not so complex that you have to invoke a Creator or think of the organ/feature as “designed”. There are many traits that may have just been slightly advantageous at the beginning, but then became sequentially more complex through mutations and eventually became essential to the survival of a creature. These features are also not perfect: here is an excellent article about why human eyes are actually not that great and have plenty of flaws. 

On the subject of eye evolution: in the video, they talk about Richard Dawkins’ book “Climbing Mount Improbable” and get many of their ideas from it. The book itself is based on a lecture he did in the early 90s that is now available on Youtube, and it features a really great demonstration of the evolution of the eye. I have included the part where he discusses eye evolution in the References section. 

One of the difficulties with understanding complex traits lies in the fossil record. Fossilization is an incredibly difficult process, and involves chance. If we had fossils of every single living thing that has ever existed, it would be a lot easier to trace the step-by-step lineage of the eye. However, we are not so lucky, so scientists have to make do with the living things that were fossilized and discovered. Archaeopteryx, mentioned above, is a great example of a lucky discovery that has helped us understand how birds came from dinosaurs.They bring up these evolutionary leaps from one structure to another (simple light spots to fish eyes, for example), but in reality, it was never a leap. It may look like a leap now because of the small number of fossils, but in reality, it was most likely a much smoother transition. Even with the limited numbers of fossils, we see that they line up quite well with Darwin’s ideas about natural selection. 

Point 2. 13:20 onwards “The second point with respect to natural selection is that it can’t select for end function. It doesn’t have foresight”.
They share an example of two chimpanzees, one who is more “intelligent” and the other is “brawny”, and say the following:

“Natural selection, who will it favour in that moment? Will it select for that individual who is potentially, whose progeny is going to produce more complex and more intelligent offspring? Or is it going to slide for the person who is going to reproduce fittest in the moment? And the answer is, according to Neo-Darwinists themselves, it would favour Chad [the brawny one].”

I only have one thing to say for this: as far as natural selection is concerned, individuals do not matter as much as we think they would. What does matter is the overall population and the environment it is surviving in. This emphasis on individuals is a dangerous one too, and truthfully I found their comments about “the intelligent chimpanzee getting friendzoned” to be really distasteful. At the end of the day, it does not matter if one chimpanzee is getting picked over another by females to mate with, because while those traits may be passed on, it does not determine whether the whole population will now be less intelligent and more brawny. Natural selection can raise the frequency of some mutations, but it does not mean now all the chimpanzees will be less intelligent. 

In summary:

Evolution by natural selection is a process backed by years of science. Intelligent design is not. There are perfectly good explanations for natural phenomena without the need to invoke a Creator (though I am sure one could still believe in God and agree with natural selection). Just because concepts like eye evolution may seem hard to understand does not mean we need to reach for fringe ideas immediately. Growing up Ahmadi I was always proud of being a part of a Nobel Prize winner’s community, and I am really surprised by the unscientific route Rational Religion is taking by rejecting natural selection. 

References and Reading List:

  1. The Tangled Bank: An Introduction to Evolution by Carl Zimmer
  2. Evolution: Making Sense of Life by Carl Zimmer and Douglas Emlen
  3. The Mechanisms of Evolution                    https://evolution.berkeley.edu/evolibrary/article/evo_14
  4. Is Intelligent Design Scientific? https://undsci.berkeley.edu/article/id_checklist
  5. Intelligent Design FAQ https://www.aclu.org/other/frequently-asked-questions-about-intelligent-design
  6.  Evolution of the Eye by Trevor Lamb   https://www.nature.com/scientificamerican/journal/v305/n1/full/scientificamerican0711-64.html PDF version here: https://web.archive.org/web/20131212204529/http://physics.okstate.edu/axie/courses/4313/2012fall/C7_B2_reading-evolution-of-eye-2011.pdf)
  7. Evolution of the Vertebrate Eye: Opsins, Photoreceptors, Retina and Eyecup by Trevor Lamb et al.  https://www.researchgate.net/publication/5821404_Evolution_of_the_vertebrate_eye_Opsins_photoreceptors_retina_and_eye_cup
  8. Eye Evolution and Its Functional Basis by Dan-E. Nilsson   https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3632888/
  9. The Poor Design of the Human Eye  https://thehumanevolutionblog.com/2015/01/12/the-poor-design-of-the-human-eye/
  10. The Origin and Diversification of Birds by Stephen Brusatte et al.  https://www.sciencedirect.com/science/article/pii/S0960982215009458
  11. Origin of Birds 
    https://evolution.berkeley.edu/evolibrary/article/evograms_06 
  12. Which came first? The Dinosaur or the Bird? by Michael Balter https://www.audubon.org/magazine/january-february-2015/which-came-first-dinosaur-or-bird

Dawkins takes on the evolution of the eye
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