Is Homology Evidence for Evolution? (Long Story Short, Ep. 1)

Is homology due to common descent or common design? Is descent with modification overwhelmingly obvious? The standard definition of homology is the similarity of the structure, physiology, or development of different species of organisms based upon their descent from a common evolutionary ancestor- the structural identity of parts in distinct species such as the human hand, the wing of a bird, and the flipper of a seal. But is this really the case?

The answer: “Homology can’t be used as evidence for evolution because it assumes the very thing it’s trying to prove.” In other words, Homology therefore evolution, evolution therefore homology. “And when biologists try to fix this by pointing to DNA or other areas it only further undermines the case.”

“Long Story Short," is a new video series that compresses key points in the debate between Darwinism and intelligent design into a very welcome format: concise, accessible, and funny. As the narrator explains, “One of the main arguments Darwin used for his theory was that of homology, these odd similarities between very different animals. Why would they be so similar unless they were related?”

The full series can be found at this playlist:

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[dutchchatham]

Quick question. If evolution was debunked tomorrow, how would that support a biblical narrative?

[deafgrapes]

6:00 that is not cherry-picking, cytochrome c genes are used for phylogenetic trees that include distantly related species, while cytochrome b genes are used for closely related species. Let me give an analogy, when you see two people, there is a good chance that you can tell if they are of the same or different race. How could you tell? Through the color of their skin, the shape of their face, maybe even through their height. For example, you are given 4 individuals, 2 have white skin, blonde hair and blue eyes, while the other 2 have dark skin, curly hair and brown eyes. Through this information alone you are able to know that the 2 individuals who have white skins are more closely related than any of the two individuals who have dark skin and vice versa. However, let's say that we have 1 individual with white skin is blood type A, and the other is type O, while one of the dark skinned individuals was type A and the other type B. Would we say that the white individual with type A blood is more closely related to the dark individual who was also type A compared to the white skinned person who is type O? No, because skin color is more conserved than blood type among distantly related people. Similarly, cytochrome c is much more conserved than cytochrome b over distantly related species.

[brantgentry]

What he is talking about is macroevolution, not microevolution. Macro has never been observed or detected

[YourArmsGone]

Could your please include your sources in the video description.

[timeshark]

_"Is homology due to common descent or common design? Is descent with modification overwhelmingly obvious?"_
- *Common descent and yes... unless you want to argue that your designer is incredibly wasteful and bad at designing, and ignore descent with modification that we made use of through selective breeding in agriculture to end up with ALL of our important crops and livestock...*


Let me congratulate you for making an almost honest creationist video though. You almost represented the question/idea properly and only took a few quotes and analogies out of context. For a creationist, only misrepresenting things some of the time is a step up... though you still played some dishonest games and ignored everything that doesn't support your claims.

[KenJackson_US]

The bigger problem with definition is the definition of the word *"evolution"* itself. When most creationists say "evolution", they typically mean the hypothetical process from primordial soup to man. When an most evolutionists say "evolution", they typically mean the non-controversial process that results in new species. But they _always_ say you've defined it wrong.

[Thatonedude]

"a succession of very similar forms... could instead point to a common designer"

Could it? Given no information besides the commonality of the forms, could you determine that the cars had a common designer, or a designer at all? It seems like you would need more information to determine that. Like, say, 'was the form designed at all?' I don't know how you can say anything about whether they share a designer if you can't demonstrate that the things were designed to begin with



Also, there's something I'm curious about. Given the scientific view, more similarity generally means closer relatedness, while less similarity generally means more distant relatedness. Under the "common design, common designer" view, does more similarity mean common designer(s), while less similarity means different designer(s)? To put it another way: According the the theory of evolution, similar organisms are similar because they are more closely related, and dissimilar organisms are dissimilar because they are more distantly related. According to "common design, " similar organisms are similar because they have a common designer, and dissimilar organisms are dissimilar because... they also have a common designer? Certainly, a designer doesn't need to design everything the same, but you can't say that similarity is evidence of a common designer if difference isn't evidence for a different designer- - that would be special pleading. So do you think that organisms that scientists would say are more distantly related (i.e., organisms that are substantially different morphologically and/or genetically) can be explained by "different design, different designer?"

[GC-EXTREME]

"Why would they be so similar unless they were related?"

MAYBE because they have the same DESIGNER!! Does that thought ever come into your mind?
Maybe the structure and design works so well, the DESIGNER used it in many different applications?

Oh a Chevy Silverado and a Ford Mustang both have wheel bearings and windshield wipers....they must be related!!!

[WaelHamadeh]

Fantastic! Clear, witty, funny and informative. Looking forward to the sequels!

[pedroamaralcouto]

I think there are several issues with the arguments.

The idea of homology being evidence for common ancestry (I'm assuming that's what you call "evolution") are not mere similarities.
Those similarities must look inherited instead of, for instance, based on composition (like a having a toolbox with reusable tools used for unrelated beings).
Bats and birds have wings, fish, whales and seals have fins, but those similarities aren't unrelated and are superficial.
The video doesn't have that explanation before trying to refute it.

It seems, the idea that homology as an evidence for common ancestry is circular seems to be based on definitions: homology is a similarly that was inherited.
If A descents from B, then they have similarities which A inherited from B. That is not a circular argument. It merely requires evidence that similarities are inherited.
Otherwise, something like this is also circular:
1) Being taller is having a greater height
2) A has a greater height than B
3) Therefore, A is taller than B
Another thing is asking evidence for 2).

I tried to find information about cytochrome-b associated to the theory of evolution problems. I only found a Red It forum ("Does cytochrome-B disprove evolution?").
It says: "[...] I was advised that Cytochrome-B would challenge my assumptions since cats and whales group within primates (apparently) [...] The idea that cats and whales group within primates came from a book on intelligent design called Explore Evolution. [...]"
It states Michael Lynch was misquoted in that book.
I think you should provide your sources to check them.

[antiHUMANDesigns]

No, wait a second! It was Carl von Linné, about 100 years before Darwin, who classified all living things and noticed the nested hierarchy of homology in all living things.
All Darwin did was provide an explanation for the question posed by Carl von Linné, the challenge he put on the scientific community to find an explanation for why life falls into a nested hierarchy of traits.
We already knew that artificial selection could produce new varieties, like what we have done to dogs, cats, and all sorts of plants and crops. What Darwin realized is that something he called "natural selection" could act as artificial selection, and thus produce variations based on fitness to the environment, and that this explains the observations of Carl von Linné.

[betawithbrett]

I teach ancient Greek so let me clarify the point at 2:45.
Homology in English is borrowed from ancient Greeks word ὁμολογία homologia.

The prefix homo meant similar or same. Many know that but don't know where logia or "logy" in English derives etymologically (a word's origin and family tree).
λόγος in Greek has do with all of the following:
1. reason, logic, rational thought
2. spoken words of logical reason
The verb in Greek sharing the same root is λέγω lego to speak rationally.

So the misdefining of this by scientists is ignorant at best or dishonest at worst. The irony is the Latin word "science" means knowledge... but these are not knowledgeable on this definition.

[Zancibar]

So we can all agree that descent with modification is possible up to a limit. Mind to show evidence for a solid limit then? Because evidence for limitlessness is weak (when you consider solid predictions about genetics, well documented evolutionary adaptations in bacteria, insects* fruits, vegetabbles and cattle and literally having the entire evolutionary history of various living organisms weak) but present. Also evolution is the descent with modifications I see most of the people here accept, the thing is that evolution says that we have no reason to believe there is a limit to it. And it doesn't really contradict a creator either, it just doesn't need one.

[daysmanoftheages]

The religion of evolution. You need lots more faith.

[B]

If I've designed and created a line of mobile phones. Each and every phone will share very similar functionality, you will be able to find similarities quite easily, despite there being apparent differences too. If I've used certain amount of lithium, silicon, aluminium etc for each phone then the molecular structure of these metals will exist in all the phones in varying degrees. So they won't match identically unless I've used the exact amount of metals in one phone and another. You may be able to tell which is my earlier iteration simply by seeing which has fewer tools or bells and whistles compared to my more modern iterations. If i were to line up all my phones in order of date it was created, you would clearly see an 'evolution' in my phone designs. Now if i were to bring a line of led tvs from another designer. It would contain some of the same metals. It would look somewhat similar to my phones but bigger, serve somewhat same functionality minus few things, so it would be easy to infer common designer, yet we will only know if there is in fact the same designer for both only if we are told.

I can fit all of the above data in an equivalent to phylogenetic tree to infer common ancestry. So even though the tvs and phones are designed i can mislead simply by how i compile my data.

So the take home message is that the prior assumption will affect the conclusion.

[anaccountmusthaveaname]

This video is just semantics. Why not actually discuss the phenomenon and not the word that describes it. If I say that structural similarities between animals are evidence of common ancestry, this video has nothing to respond. Because I did't use the word homology. And yet my argument points to the exactly same observation of nature.

[nathanthreeleaf]

These animated videos are really great. I think the voice actor, dialogue, research put into it and whatever animation/production studio you went with, has done a fantastic job.

[jkim]

Darwin and other biologists didn’t get the ball to say “I don’t know”.

[sbgtrading]

Good video in general...but I need more detail about why "cytochrome b" refutes common descent. Is it because "b" is present in species that are in radically different supposed lineages? Is the "b" gene in whales exactly the same as the one in cats? So if they are far divergent, they should not have the exact same "b" gene?

[ozredneck]

Survival of the fittest is a tautology.

Which ones are the that survive

Which ones that are the fittest, around and around we go.