Understanding through Discussion


Welcome! You are not logged in. [ Login ]
EvC Forum active members: 122 (8774 total)
Current session began: 
Page Loaded: 07-24-2017 4:33 AM
362 online now:
CRR, Dr Jack, Heathen (3 members, 359 visitors)
Chatting now:  Chat room empty
Newest Member: Tom Larkin
Post Volume:
Total: 814,489 Year: 19,095/21,208 Month: 1,854/3,111 Week: 75/574 Day: 7/68 Hour: 1/3

Announcements: Reporting debate problems OR discussing moderation actions/inactions


Thread  Details

Email This Thread
Newer Topic | Older Topic
  
1
23456
...
70NextFF
Author Topic:   Nothing in biology makes sense except in the light of evolution.
CRR
Member
Posts: 441
From: Australia
Joined: 10-19-2016
Member Rating: 1.2


Message 1 of 1038 (806546)
04-26-2017 4:11 AM


This side issue has been clogging up the How do you define the word Evolution? thread, for example, see Message 467 and read downstream. It's being spun off into it's own thread to see if evolutionists can defend it.

Edited by Admin, : Rewrite text of opening post.


Replies to this message:
 Message 3 by Dr Adequate, posted 04-26-2017 9:31 AM CRR has not yet responded
 Message 4 by Taq, posted 04-26-2017 10:52 AM CRR has not yet responded

  
Admin
Director
Posts: 12517
From: EvC Forum
Joined: 06-14-2002
Member Rating: 3.1


Message 2 of 1038 (806548)
04-26-2017 8:59 AM


Thread Copied from Proposed New Topics Forum
Thread copied here from the Nothing in biology makes sense except in the light of evolution. thread in the Proposed New Topics forum.
    
Dr Adequate
Member
Posts: 15946
Joined: 07-20-2006
Member Rating: 3.8


Message 3 of 1038 (806552)
04-26-2017 9:31 AM
Reply to: Message 1 by CRR
04-26-2017 4:11 AM


It's being spun off into it's own thread to see if evolutionists can defend it.

We did, so that's a yes.

As you had no comeback, the question is now whether you can make so much as a token effort to refute it.


This message is a reply to:
 Message 1 by CRR, posted 04-26-2017 4:11 AM CRR has not yet responded

  
Taq
Member
Posts: 6799
Joined: 03-06-2009
Member Rating: 3.9


(1)
Message 4 of 1038 (806562)
04-26-2017 10:52 AM
Reply to: Message 1 by CRR
04-26-2017 4:11 AM


Introns and Exons
Let's look at the first problem.

A eukaryotic gene is made up of introns and exons. When DNA is transcribed into RNA both the exons and introns are made into RNA. However, during mRNA processing the introns are clipped out leaving just the exons which are then translated into protein. The introns are not translated into amino acid sequence.

When we observe homologous genes between species we see that there is more DNA sequence shared between exons than between introns. This divergence between exons and introns roughly increases with the morphological differences between species. However, introns have nothing to do with morphology, so why do we see this trend?

Only evolution is able to explain this trend. Negative selection in the functional exons results in sequence conservation, whereas mutations in the introns are fixed by neutral drift. This produces the divergence between the exons and introns. This divergence increases with evolutionary distance since there has been more time for neutral drift to fix mutations in the introns.

The divergence between exons and introns only makes sense in the light evolution. I have yet to see a single other theory that explains this pattern, or even attempts to explain it in a reasonable, cogent, and testable manner.

Edited by Taq, : No reason given.

Edited by Taq, : No reason given.


This message is a reply to:
 Message 1 by CRR, posted 04-26-2017 4:11 AM CRR has not yet responded

Replies to this message:
 Message 489 by aristotle, posted 06-16-2017 3:05 AM Taq has responded

  
CRR
Member
Posts: 441
From: Australia
Joined: 10-19-2016
Member Rating: 1.2


Message 5 of 1038 (806630)
04-26-2017 11:15 PM


"Nothing in Biology Makes Sense except in the Light of Evolution" is an article by Theodosius Dobzhansky published in The American Biology Teacher, Vol. 35, No. 3

It's worth reading to get context for the discussion. I found a pdf copy here.

Let's discuss the article and the extent to which quote "Nothing in Biology Makes Sense except in the Light of Evolution" is applicable today.

My view is that the title was hyperbolic; not to be taken literally. After all scientists were making sense of biology long before Darwin's theory of evolution appeared. Rather, in the article Dobzhansky covered a number of topics that he thought only made sense in the light of evolution. The article was written in 1973 and like anything that was written 40 years ago some specific examples might be out of date and I don't want to dwell overmuch on that aspect.


Replies to this message:
 Message 6 by Dr Adequate, posted 04-26-2017 11:22 PM CRR has not yet responded
 Message 8 by Taq, posted 04-27-2017 10:36 AM CRR has not yet responded

  
Dr Adequate
Member
Posts: 15946
Joined: 07-20-2006
Member Rating: 3.8


(1)
Message 6 of 1038 (806632)
04-26-2017 11:22 PM
Reply to: Message 5 by CRR
04-26-2017 11:15 PM


After all scientists were making sense of biology long before Darwin's theory of evolution appeared.

That's debatable. They were accumulating facts, but were they making sense of them?


This message is a reply to:
 Message 5 by CRR, posted 04-26-2017 11:15 PM CRR has not yet responded

Replies to this message:
 Message 7 by Chiroptera, posted 04-27-2017 9:12 AM Dr Adequate has not yet responded

  
Chiroptera
Member
Posts: 6385
From: Oklahoma
Joined: 09-28-2003
Member Rating: 5.4


Message 7 of 1038 (806668)
04-27-2017 9:12 AM
Reply to: Message 6 by Dr Adequate
04-26-2017 11:22 PM


Was biology even a science (as we recognize the word) before Darwin? I confess I don't know.

I'm reminded how it was never a scientific belief that the heavens revolved about the earth since science itself only developed during the transition to the heliocentric model.

I wonder whether biology was in a similar state before Darwin?


I believe in a relatively equal society, supported by institutions that limit extremes of wealth and poverty. I believe in democracy, civil liberties, and the rule of law. That makes me a liberal, and Iím proud of it. -- Paul Krugman

This message is a reply to:
 Message 6 by Dr Adequate, posted 04-26-2017 11:22 PM Dr Adequate has not yet responded

Replies to this message:
 Message 18 by CRR, posted 05-01-2017 6:47 AM Chiroptera has responded
 Message 32 by Dredge, posted 05-03-2017 12:49 AM Chiroptera has not yet responded

  
Taq
Member
Posts: 6799
Joined: 03-06-2009
Member Rating: 3.9


Message 8 of 1038 (806695)
04-27-2017 10:36 AM
Reply to: Message 5 by CRR
04-26-2017 11:15 PM


CRR writes:

Let's discuss the article and the extent to which quote "Nothing in Biology Makes Sense except in the Light of Evolution" is applicable today.

That's exactly what I did in message #4 with my example of exon and intron divergence. Perhaps you could start with that example.

Edited by Taq, : No reason given.


This message is a reply to:
 Message 5 by CRR, posted 04-26-2017 11:15 PM CRR has not yet responded

  
Taq
Member
Posts: 6799
Joined: 03-06-2009
Member Rating: 3.9


(4)
Message 9 of 1038 (806707)
04-27-2017 10:54 AM


The Nested Hierarchy
One example of a set of observations that dates to before Darwin is the nested hierarchy of shared features. Prior to evolution, there was simply no explanation as to why shared features were distributed in this manner.

Why does everything with fur also have three middle ear bones? Why does everything with a back bone also have a backwards facing retina when some animals without a backbone have forward facing retinas? Why does everything with fur also have mammary glands? Why does everything with feathers have flow through lungs?

There was simply no answers for these questions until Darwin had a Eureka! moment. In fact, you can find that moment immortalized in his very notebooks where he drew this diagram:

The nested hierarchy only makes sense in light of a process with common ancestry and descent with modification, what Darwin called evolution.

I have yet to see a single ID/creationist explain this pattern. There is simply no reason why a designer would force separately created species into a nested hierarchy. When humans design things we don't force those designs into a nested hierarchy. Things like cars, paintings, tools, and buildings don't fall into a nested hierarchy even when they are designed by a single human. There is absolutely no functional reason why life would need to fall into a nested hierarchy. The only explanation we have for this pattern is evolution, and this pattern of shared features only makes sense in the light of evolution.

Edited by Taq, : No reason given.


Replies to this message:
 Message 10 by Chiroptera, posted 04-27-2017 11:15 AM Taq has not yet responded
 Message 16 by RAZD, posted 04-28-2017 9:22 AM Taq has not yet responded
 Message 491 by aristotle, posted 06-16-2017 3:55 AM Taq has not yet responded

  
Chiroptera
Member
Posts: 6385
From: Oklahoma
Joined: 09-28-2003
Member Rating: 5.4


(3)
Message 10 of 1038 (806722)
04-27-2017 11:15 AM
Reply to: Message 9 by Taq
04-27-2017 10:54 AM


Re: The Nested Hierarchy
I've said many, many times that the nested hierarchy is, for me, the single best evidence for common descent.

I believe in a relatively equal society, supported by institutions that limit extremes of wealth and poverty. I believe in democracy, civil liberties, and the rule of law. That makes me a liberal, and Iím proud of it. -- Paul Krugman

This message is a reply to:
 Message 9 by Taq, posted 04-27-2017 10:54 AM Taq has not yet responded

Replies to this message:
 Message 11 by Tanypteryx, posted 04-27-2017 11:33 AM Chiroptera has acknowledged this reply
 Message 490 by aristotle, posted 06-16-2017 3:44 AM Chiroptera has not yet responded

  
Tanypteryx
Member
Posts: 1514
From: Oregon, USA
Joined: 08-27-2006
Member Rating: 4.9


(1)
Message 11 of 1038 (806738)
04-27-2017 11:33 AM
Reply to: Message 10 by Chiroptera
04-27-2017 11:15 AM


Re: The Nested Hierarchy
I've said many, many times that the nested hierarchy is, for me, the single best evidence for common descent.

Me too.

One of the really cool things about it is the nested hierarchy carries through to the newest comparisons of whole genomes and also with comparisons of individual genes across categories of life from phyla, classes, orders, etc.

We have been able to reclassify organisms based on genetic evolutionary history and biology makes more and more sense in light of evolution.

It is really a fun time to be involved in biological sciences.


What if Eleanor Roosevelt had wings? -- Monty Python

One important characteristic of a theory is that is has survived repeated attempts to falsify it. Contrary to your understanding, all available evidence confirms it. --Subbie

If evolution is shown to be false, it will be at the hands of things that are true, not made up. --percy

The reason that we have the scientific method is because common sense isn't reliable. -- Taq


This message is a reply to:
 Message 10 by Chiroptera, posted 04-27-2017 11:15 AM Chiroptera has acknowledged this reply

    
Taq
Member
Posts: 6799
Joined: 03-06-2009
Member Rating: 3.9


(2)
Message 12 of 1038 (806772)
04-27-2017 5:20 PM


Correlation Between Independent Phylogenies
The next example of why biology only makes sense in the light of evolution is the correlation between phylogenies based on morphology and phylogenies based on DNA sequences. In essence, it is a combination of the nested hierarchy and genetic divergence which we have discussed in part in previous posts.

So what is the deal here? Let's use the cytochrome c gene as our specific example. It is a protein that sits in the mitochondrial and pushes protons across that membrane against a concentration gradient. It plays a vital, yet mundane role in metabolism. More importantly, the protein has nothing to do with what an animal looks like (i.e. morphology).

So what happens when we organize animals into phylogenies based on morphology and based on cytochrome c DNA sequences? We get an exact match. The phylogenies are exactly the same. The more physically similar two animal species are, the more similarity there is in their cytochrome c gene, even though morphology and the DNA sequence of cytochrome c are completely independent of one another. You can read more here:

quote:
So, how well do phylogenetic trees from morphological studies match the trees made from independent molecular studies? There are over 10^38 different possible ways to arrange the 30 major taxa represented in Figure 1 into a phylogenetic tree (see Table 1.3.1; Felsenstein 1982; Li 1997, p. 102). In spite of these odds, the relationships given in Figure 1, as determined from morphological characters, are completely congruent with the relationships determined independently from cytochrome c molecular studies (for consensus phylogenies from pre-molecular studies see Carter 1954, Figure 1, p. 13; Dodson 1960, Figures 43, p. 125, and Figure 50, p. 150; Osborn 1918, Figure 42, p. 161; Haeckel 1898, p. 55; Gregory 1951, Fig. opposite title page; for phylogenies from the early cytochrome c studies see McLaughlin and Dayhoff 1973; Dickerson and Timkovich 1975, pp. 438-439). Speaking quantitatively, independent morphological and molecular measurements such as these have determined the standard phylogenetic tree, as shown in Figure 1, to better than 38 decimal places. This phenomenal corroboration of universal common descent is referred to as the "twin nested hierarchy". This term is something of a misnomer, however, since there are in reality multiple nested hierarchies, independently determined from many sources of data.
http://www.talkorigins.org/...1.html#independent_convergence

This only makes sense in the light of evolution. Only evolution would produce matching phylogenies for both morphology and DNA. A designer, especially an all powerful and all knowing one, could create two nearly identical species with genomes that share less than 50% sequence, if the designer wanted to. A good analogy is computer programs. The web browser Google Chrome looks nearly identical on both the Mac and PC, yet the computer code underneath the web browser on the two platforms is very different.

Biology is no different. If you wanted to, you could completely change the anti-codons on the tRNAs. This would allow you to produce identical proteins from very different DNA sequences. This is just one change you could make. Hypothetically, you could produce two nearly identical species from proteins that share very little sequence as well since protein function is very redundant when it comes to sequence.

On top of that, a designer could mix and match genes from very divergent species. For example, a designer could use an exact copy of a jellyfish gene in the mouse genome. In fact, humans have done that very thing, and what resulted was a green fluorescent mouse that is used in scientific research. Even when humans design organisms we routinely violate a matching phylogeny because there is absolutely no functional reason why you would need to have these phylogenies match one another.

In the end, only evolution can explain this overarching and all encompassing observation that exists in biology. The matching phylogenies are a massive part of biology, and only evolution explains it. Those phylogenies make zero sense without evolution.

Edited by Taq, : No reason given.


  
Taq
Member
Posts: 6799
Joined: 03-06-2009
Member Rating: 3.9


(2)
Message 13 of 1038 (806773)
04-27-2017 5:34 PM


Genetic Equidistance
The next example of why biology only makes sense in the light of evolution is the observation of genetic equidistance.

What is genetic equidistance? This is when the % DNA similarity is about the same between two Species A and Species C, and between Species B and Species C.

Let's look at one of those trio of species: humans, mice, and chickens.

Let's also use the same gene from the previous post: cytochrome c.

If we go to Homologene at NCBI, we can search for cytochrome c (cycs) and get a pairwise alignment score for humans, mice, and chickens. What do we get?

Human v. mouse: 90.5% similar
Human v. chicken: 81.6% similar
Mouse v. chicken: 81.9% similar

Human and mouse are genetically equidistant from the chicken. But why? Only evolution can explain this. Again, we go back to phylogenies:

Humans are A, mice are B, and chickens are C. This is the accepted evolutionary relationships between humans, mice, and chickens. As you can see, if you trace A to the node that connects it to C, it is the same node that connects B to C. A and B share the same common ancestor with C, meaning that they evolutionary distance between A and C is the same as the evolutionary distance between B and C. This is why we see genetic equidistance, because humans, mice, and chickens evolved from the same common ancestor, with the human/mouse lineage splitting after it splits with the chicken lineage.

In fact, you can pick any trio you want at Homologene. You can use humans, cows, and frogs. You could do mice, chickens, and frogs. Every time you draw up the evolutionary relationships and make the prediction of where you should see genetic equidistance, sure enough, there it is.

Again, only evolution explains this. This only makes sense in the light of evolution.

Edited by Taq, : No reason given.


  
Tanypteryx
Member
Posts: 1514
From: Oregon, USA
Joined: 08-27-2006
Member Rating: 4.9


(4)
Message 14 of 1038 (806774)
04-27-2017 7:41 PM


Endogenous Retroviruses
Endogenous Retroviruses (ERVs) have left the record of infections in our DNA and the DNA of many other organisms.

Comparing ERVs in related species shows that some are in the same exact positions in the genome. Some unique ERVs are found in each species that can be attributed to infections (insertions) since the species diverged from their common ancestor. Comparing the ERVs in identical spots in the genomes often show slight differences between species that can be attributed point mutations that have occurred since divergence.

I think it would be hard to explain why a designer would have inserted this pattern of ERVs that also fit into a nested hierarchy.

Interestingly, some ERVs appear to now have active regulatory roles in our genome.

quote:
Humans share about 99% of their genomic DNA with chimpanzees and bonobos; thus, the differences between these species are unlikely to be in gene content but could be caused by inherited changes in regulatory systems. Endogenous retroviruses (ERVs) comprise ∼ 5% of the human genome. The LTRs of ERVs contain many regulatory sequences, such as promoters, enhancers, polyadenylation signals and factor-binding sites. Thus, they can influence the expression of nearby human genes.

from part of the abstract of:
Endogenous Retroviruses and Human Evolution, Konstantin Khodosevich,corresponding author Yuri Lebedev, and Eugene Sverdlov.
Comp Funct Genomics. 2002 Dec; 3(6): 494Ė498.

What if Eleanor Roosevelt had wings? -- Monty Python

One important characteristic of a theory is that is has survived repeated attempts to falsify it. Contrary to your understanding, all available evidence confirms it. --Subbie

If evolution is shown to be false, it will be at the hands of things that are true, not made up. --percy

The reason that we have the scientific method is because common sense isn't reliable. -- Taq


Replies to this message:
 Message 17 by Taq, posted 04-28-2017 11:04 AM Tanypteryx has acknowledged this reply

    
Dr Adequate
Member
Posts: 15946
Joined: 07-20-2006
Member Rating: 3.8


(1)
Message 15 of 1038 (806775)
04-27-2017 7:53 PM


Let me add what I posted on the other thread.

A lot in biology makes perfect sense without evolution. E.g. the physical adaptations of the giraffe to cope with its height are functional requirements ...

Further to my previous remarks, I would point out that only evolution makes sense of the fact that these are adaptations. Why should the neck of the giraffe, which is long and goes up, bear such a striking resemblance to the neck of, say, a pig, which is short and goes along?

(If we found two analogous designed objects, such as a footbridge across a short stream and a radio mast, which had the same basic plan, which were so obviously variations on the same theme, this would not make sense to us, we would be deeply puzzled.)

Now evolution does make perfect sense of the pig and the giraffe: they have common ancestry, they are adaptations of the same thing, and per the theory of evolution, evolution cannot scrap a design and go back to the drawing board.

Without evolution, how would you make sense of it? A creationist might get as far as "God chose to do it that way for some reason", but what is the reason?

---

This is a particularly good example because it is CRR's. He had the whole of nature to choose from to find one thing that does make sense without evolution, and he chose something that flagrantly doesn't.

Should we tell him about the recurrent laryngeal nerve?


  
1
23456
...
70NextFF
Newer Topic | Older Topic
Jump to:


Copyright 2001-2015 by EvC Forum, All Rights Reserved

™ Version 4.0 Beta
Innovative software from Qwixotic © 2017