Evolution and Image Bearers, Part 1 | The BioLogos Forum

first about the har1- you are actually said what im saying. i doesnt said its disprove evolution. i just say that in this way we can never disprove evolution. for example- lets say that the overall genetic similarity between some fish and chimp is closer then chimp and human. in this case you will claim that human and chimp isnt a close relative compare to fish?

about the human variation- the answer can be very simple: in the past the population was very small. and because of that there was a lot of variations(fixation time of mutations will take short time).

  1. even if what you said is true- its still the same kind of genus- the homo genus. so we dont need any evolution to explain this.

hi john. here is another problem-bacteria is about 4 bilion years old .lets say that generation of bacteria is about a day. its mean that the variation between bacteria wil be more then there entire genome! how its fit with molecular clock?

second- if human and chimp split before 6 my-why there clock is so different from each other(bottleneck?)?

You can disprove evolution. You just can’t do it by taking a sequence of nucleotides 118bp long and then doing a simple comparison between 3 species: Chicken, Chimp and Human. That would be stupid and would only prove that humans have likely undergone accelerated evolution in that sequence. You need to introduce more species and then look for patterns of relatedness.

For example: If humans had an identical set of mutations as baboons, but Gibbons, Orangutans, Gorillas, Chimpanzees and Bonobos lacked these then that would be incredibly difficult to explain because of the way that all of these other apes sit on the same branch as humans. Humans and Baboons are too far removed for ILS to have an effect. Likewise, it shouldn’t be possible for humans to share a sequence with fish that other primates don’t.

about the human variation- the answer can be very simple: in the past the population was very small. and because of that there was a lot of variations(fixation time of mutations will take short time).

If this was true then we should expect to see a lot of variation amongst Neanderthals. But we don’t. People once thought that this might have been the case. We have since sequenced 12 different Neanderthals from a diverse area and found that they are all incredibly similar. That ancient diversity seems to be non-existent and so the best explanation then is that humans and Neanderthals have been evolving separately from each other for hundreds of thousands of years.

  1. even if what you said is true- its still the same kind of genus- the homo genus. so we dont need any evolution to explain this.

Perhaps not, but what you need is hundreds of thousands of years. You also need to acknowledge that even if they are the same genus and could interbreed, that evolution can produce very different characteristics between populations.

It isn’t the mutation rate in humans and Chimpanzees is similar.

Bacteria swap genes through a process called horizontal gene transfer. This means that any signal of variation between bacteria will easily be drowned out by the fact that these populations are swapping genes with each other.

ace, you said:

“Likewise, it shouldn’t be possible for humans to share a sequence with fish that other primates don’t.”-

why not? it will be a case for convergent evolution. the protein sequence of prestin gene is closer between some whale and bats but not in some other bats and whale. its mean that according to this protein whales are more close to bats then other whales! so again- there is no way to disprove evolution in genetic terms.

you said:

“the best explanation then is that humans and Neanderthals have been evolving separately from each other for hundreds of thousands of years”-

maybe. but they are still humans with the same biological systems. by the way- the human population actually show that the earth age may be young. for example: the corrent population doubeling is about one in 40 years. lets say that in the past it was even 1000% slower because of wars, diseases and so on. so to get the corrent population( near 7 bilion) we will need only 30 generations of doubeling (2^30 ,start from 2 people). this give us only 12,000 years to 2 people. and this is even if we add 1000% slower rate!

you said:

“Bacteria swap genes through a process called horizontal gene transfer.”-

yes. but those genes are still get mutations. so the basic claim stays. lets take another example without lgt: fly generation is about not more then one month. so even if one generation mean 1 new mutation we will need only 10^8 month to change is entire genome. or about 10^7 years. so the variation between flyes species need to be more then there entire genome.

Convergent evolution happens to phenotypes. It is incredibly rare that it can happen at the level of the genotype because there are often many different ways to encode a similar function. I’ve seen one or two limited examples of genotypic homoplasy but it tends to effect only a handful of bases - nothing close to the level of similarity we see between closely related species due to inheritance.

Not maybe. It is. You’ve yet to propose a better explanation.

but those genes are still get mutations

And those mutations can go on to get swapped out again. Do you see the problem?

need only 10^8 month to change is entire genome

You clearly don’t understand genetics or neutral theory. If a sequence is neutral (aka: Junk DNA), it will gain mutations at the background rate and these will never be filtered out. If a sequence is needed then any deleterious mutation will be weeded out fairly quickly because that sequence is needed for the success of that line. This means that it doesn’t matter how many generations you have, some sequences will always remain as long as the species needs them because of selective pressure.

Here is one paper that looks at the divergence times of flies based on molecular clocks. Why don’t you read this and let me know what you find?

hi ace. you said:

“I’ve seen one or two limited examples of genotypic”-

what about hundreds of examples?:

http://www.nature.com/news/convergent-evolution-seen-in-hundreds-of-genes-1.13679

yes. its still not a lots of bases per gene, but where is the limit of convergent? half a gene? 1 gene? 10 genes?

you said:

“If a sequence is neutral (aka: Junk DNA), it will gain mutations at the background rate and these will never be filtered out.”

i actually do talk about junk(according to your number is about 90%). so again- variations between fly species need to be at least 90% of their entire genome. how its feat with the data?

what about hundreds of examples?:

Convergent evolution seen in hundreds of genes | Nature

Once again you’re posting something as evidence that you haven’t properly understood. That study didn’t find what you think it did. That convergence they found was on the level of proteins. They found similar amino acids evolving in similar locations in certain proteins between dolphins and bats. But there multiple ways to code for amino acids and so the genetic sequences were still clearly different.

according to your number is about 90%

It is 90% for humans. Some animals have almost no junk. I don’t know what it is for flies.

not realy. like i said before- the chance for specific amino acid is 1\20. the chance for specific nucleotied is 1\4. so from pure chance prespective, without any selection involve, is more rare to get the same amino acid compare to the same dna base. so convergent in the aa level is even more impressive then DNA level.

and i can give you example with full genes. but in this case evolution scientists solve this by lgt.

about molecular clock- ok. some fish has genome size about 40 times larger then human:

so its mean that this fish is different about 98% of its genome compare to human. it can be the result of duplications.but its still impressive.

These are functional sequences. Functional sequences don’t evolve purely by chance. They evolve gradually in a step-wise fashion through selection working on available mutations.

like i said before- the chance for specific amino acid is 1\20. the chance for specific nucleotied is 1\4

Your maths is wrong here. You are comparing two different things: The chance of 2 nucleotides corresponding to the chance of two amino acids corresponding. Amino acids are made up of three nucleotides, so the chance of an exact match in nucleotide sequence is (1/4)^3 = 1.5/100 whereas the chance of there evolving the same nucleotide is roughly 1/20 = 5/100.

is more rare to get the same amino acid compare to the same dna base

It doesn’t matter how rare it is. The point is that this doesn’t refute the fact that closely related animals should share similar sequences to the exclusion of others because these sequences are clearly different.

It would only be surprising if the DNA sequences were identical but they aren’t. I would even expect this to be the case if intelligent design were true: In this case, not only do the different sequences fail to disprove common descent but they also challenge one of intelligent design’s favourite mantras: Common design, common designer. I guess creationists only use that argument when it suits them and they conveniently forget about it when it looks like there isn’t common design in cases of covergent evolution?

and i can give you example with full genes. but in this case evolution scientists solve this by lgt.

Well then once again, this is not something that disproves evolution is it? I’ve already explained to you that we know and understand that lateral gene transfer is common in prokaryotes.

“Amino acids are made up of three nucleotides, so the chance of an exact match in nucleotide sequence is (1/4)^3”-

why? we talk about one nucleotide against one amino acid. not 3 nucleotides. so its 1/4 vs 1/20 (again- from pure chance).

“It would only be surprising if the DNA sequences were identical but they aren’t.”

they are actually. creationists claim that apes and human designed separately. so most of their genome is indeed because of convergent design and not evolution.

“I’ve already explained to you that we know and understand that lateral gene transfer is common in prokaryotes.”-

actually im not talking about prokaryotes but eukaryotes:

so again- nothing can disprove evolution. so how can we test it?

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