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Author Topic:   Any practical use for Universal Common Ancestor?
caffeine
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Posts: 1702
From: Prague, Czech Republic
Joined: 10-22-2008
Member Rating: 2.9


Message 48 of 1362 (843895)
11-22-2018 2:35 PM
Reply to: Message 43 by Pressie
11-22-2018 4:29 AM


Luckily for humanity no form of the earth sciences even claims that.

What? That sentence is going to require some clarification. All life on earth today did indeed evolve from a microbe that existed billions of years ago.

If your point is that 'earth sciences' is different than biology, then I have no idea why you're making it.

If your point is that my and Dredge's understanding of the situation is facile, then explain why. That could be interesting and educational. But without that what's the purpose of your post?


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caffeine
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Posts: 1702
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Message 58 of 1362 (843907)
11-22-2018 3:57 PM
Reply to: Message 52 by Faith
11-22-2018 3:06 PM


Re: Another useful application of evolutionary theory
Oh it must have occurred many times, in many places where a new isolated population that no longer breeds with the parent population has formed and gets called a new "species."

Tried to ignore your nonsense, as it's not supposed to be the topic of this thread, but I'm only human.

Species of sexually reproducing organisms often have genetic barriers that prevent them from interbreeding - they either do not produce offspring or those they do are infertile. The genetic basis for this comes in two main categories. One is difference in ploidy - meaning the number of chromosomes. Having a different number of chromosomes doesn't necessarily prevent successful reproduction, but it often hampers it. I'm curious how your model of speciation through the loss of alleles accounts for closely related but not interfertile species with different chromosome counts.

Variations in chromosome count are not required for a lack of interfertility, however. The more common (I think?) form is known as intrinsic inviability. In this case, two populations don't have a different chromosome count; but by their gradual divergence and the accumulation of novel alleles (which you have accepted happens while pretending it doesn't), one or the other has built up a collection of alleles which work fine in their own genetic background, but make a right mess when you try and combine them with the sister species DNA.

Remember that, contrary to your claims, a gene is not 'for' a trait. A gene produces proteins, which, depending on where they're produced and in what quantity, can have all sorts of effects on the biochemistry of the organism. Alleles that evolves in species B in tandem with all the other alleles in that species genome will not necessarily have the same effect when surrounded by foreign DNA. They could cause a right ballsup.

Usually these infertility messups involve several different genes with small effect; but scientists have found cases where it's all down to one gene. In some species of monkey flower, for example, it's been isolated to one allele. If you have the allele from the common monkey flower Erythrante guttata on one chromosome, and the allele from Erythranthe nasuta, a different species, on the other, the male offspring are almost certain to be sterile. Which is not an issue, except that your idea would have us accept one of two things:

1. both these alleles were present in the ancestral population; which would mean a great difficulty in reproduction
2. one or both arose via mutation after the populations separated.

If the latter, then you've accepted that mutation creates new alleles. I predict your response would be that it only creates 'bad' alleles because it's part of the fall. But these alleles are not 'bad'. They're the standard (not sure if fixed) in their relevant populations - they only cause problems in combination with one another. By populations being seperated, new species have been created with new versions of genes.


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caffeine
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Posts: 1702
From: Prague, Czech Republic
Joined: 10-22-2008
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Message 65 of 1362 (843940)
11-23-2018 5:47 AM
Reply to: Message 61 by Faith
11-22-2018 4:14 PM


Re: Another useful application of evolutionary theory
Too much technical detail has the effect of abscuring rather than illuminating.

I tried very hard to avoid making the post too technical. The only technical concepts included in what you're quoting are fixation and alleles; which I thought you understood. Most of it's just normal, everyday words. I'm not sure how you can think you have it all figured out if any attempt to discuss how things actually work is too technical.

The only point of the post was to use practical examples of the real world that demonstrate your pet theory is wrong. New alleles arise by mutation. Therefore, selection does not mean that species somehow run out of variation. Because new variation appears. It's not that complicated.


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caffeine
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Posts: 1702
From: Prague, Czech Republic
Joined: 10-22-2008
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Message 306 of 1362 (850014)
03-28-2019 12:53 PM
Reply to: Message 283 by RAZD
03-27-2019 4:47 PM


Re: Applied Science is the use of scientific knowledge
quote:
and tell me if are you using your false definition of "genus" (which is actually species by scientific technical definition) or the actual scientific technical definition for genera?

Is there such a thing as a technical definition of genus? The best I could come up with is 'the next convenient level of taxonomic group above that of species', which is vague and arbitrary. Nor is it even accurate, since taxonomists often make use of subgenera, or species groups.

All of which renders Dredge's definition of macroevolution utterly meaningless.

quote:
If (D) and (E) are related via common ancestor (C), and (H) and (I) are related by common ancestor (G) and (F) is related to (C) by common ancestor (B), it is logical that there exists a population (A) that is a common ancestor to (B), (C), (D), (E), (F), (G), (H) and (I). If evidence of population (A) exists at the proper place in the spacial-temporal matrix, then this conclusion is validated as tentatively true because this is the best known explanation for the evidence (until a better explanation is provided).

There's more to it than that. The existence of common ancestors G and B doesn't, in itself, tell us anything about whether G and B share a common ancestor. Darwin famously speculated that life was originally breathed into 'a few forms or one', and that was a reasonable assumption at the time. Maybe there was an ancestral plant, and an ancestral animal, but these themselves were not related.

Now, however, that we know so much more about biology, we can see how much all life shares in common. It's all based on DNA and RNA, and the basic cellular machinery behind transcription and replication is the same in all organisms. If we'd discovered that plants, animals, bacteria etc had different types of molecule as the basic reproductive unit; if their replication was based on different types of chemistry, it's unlikely biologists would have concluded there was a universal common ancestor. We would have gone with Darwin's 'few forms', not his one.

I know that you are aware of all this, I just thought the way phrased it may have been unclear for some readers.

Edited by caffeine, : shouldn't post from mobile devices


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caffeine
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From: Prague, Czech Republic
Joined: 10-22-2008
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Message 595 of 1362 (851554)
04-28-2019 12:55 PM
Reply to: Message 513 by Dredge
04-19-2019 2:35 AM


Re: Another useful application of evolutionary theory
The fact you must deny is that all the novel organisms that appeared in the Cambrian explosion have no evolutionary history. In the Ediacaran, marine worms, jelly-fish and spongs existed and then, oh dear ... fish and trilobites and insects (for example) appear out of nowhere. Goodbye ToE.

What is the evolutionary link between a fish and the worms, jelly-fish and sponges of the pre-Cambrian?

An old post, but no-one seems to have responded to this bit directly yet.

There are no known jellyfish from the Ediacaran. Kimberella (below) has been described as a jellyfish, but this is generally rejected now. It's more commonly associated with molluscs (one of the phyla you think has no evolutionary history) but that too is controversial. It's not uncommon for the classification of Ediacaran fossils to bounce all over the place. Partly that's due to preservation, but of course if different animals do all have a common ancestor; it would make sense that, for animals close to the split between different groups, it would be difficult to figure out in which group they belong.

There's not really much in the way of worms, either. It's odd that you bring up worms in the connection with the idea that bilaterian phyla have no pre-Cambrian evolutionary history, though. Lots of the bilaterian phyla are worms, and their common ancestor is presumed to be some kind of worm. If you want to look for the evolutionary history of bilaterians in the late pre-Cambrian, worms are exactly what you'd be looking for.

On the other side of the explosion, there are neither fish nor insects in the Cambrian. The oldest fishes are known from the Silurian; though there are fossils from the Ordovician that have been interpreted as fish scales. If that's correct there were presumably fish that they came from. No sign of fish in the Cambrian though.

As for insects, there are no sign of them till about 90 million years after the Cambrian.

It may help to learn something about the fossil record before making conclusions based on it.


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caffeine
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From: Prague, Czech Republic
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Message 596 of 1362 (851555)
04-28-2019 1:00 PM
Reply to: Message 551 by Faith
04-21-2019 1:53 PM


Re: Another useful application of evolutionary theory
I've defined it functionally many times as exemplified by how breeds of, say, dogs, run out of variability the closer they get to being purebred. But you also can't find alleles/genes in the genome of a species for features outside the species: Is there an allele for a flat black chimp nose in the human genome?

You like to complain a lot about people not understanding your arguments or ignoring them. And yet when someone tries to explain why questions like the above do not make sense (like I did here), you tend to ignore them and go and find an insulting post to respond to and complain about instead.

May I suggest that more progress might be made if you do things the opposite way around - address the substantive posts and ignore the insulting ones?


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caffeine
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Posts: 1702
From: Prague, Czech Republic
Joined: 10-22-2008
Member Rating: 2.9


Message 611 of 1362 (851667)
04-30-2019 12:27 PM
Reply to: Message 606 by Thugpreacha
04-30-2019 11:23 AM


It seems to have been defined online:
Pure and Applied Biology...inestigating further, I visited this website: PAB. Still puzzled as to how Dredge actually got this term right, I delved a bit into just what research these folks profess...
Table Of Contents and it looks as if most of these scholars are Islamic.

That's just because it's the journal of a Pakistani university.

There is actually a Society of Applied Biologists; which publishes a journal called 'Annals of Applied Biology'. What they mean by 'applied biology' is basically agricultural science. The journal is all about studying crops, their diseases, weeds and agricultural pests.


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caffeine
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Posts: 1702
From: Prague, Czech Republic
Joined: 10-22-2008
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Message 625 of 1362 (851714)
05-01-2019 5:45 AM
Reply to: Message 616 by Dredge
05-01-2019 1:17 AM


Re: Progressive Creation
Where are the fossils that demonstrate the evolutionary links between the sponges, worms and barnacles of the pre-Cambrian and the fish of the Cambrian?

Since you seem to have ignored my last post I'll reiterate; since you apear to be a bit confused what you're supposed to be arguing for. It's controversial whether there are any sponges in the pre-Cambrian, but there are definitely no barnacles. Barnacles; like insects; are arthropods, one of those animal phyla which you were telling us has no pre-Cambrian evolutionary history.

The woms, as I said before, are the most plausible candidates for being the ancestors of some of the phyla you think don't have ancestors, so I'm not sure why you're raising them in this context.

There are still no Cambrian fish.

I strongly recommend perhaps reading a book or two about the animal fossil record; since it looks a bit silly making sweeping pronouncements about the world based on something you clearly know little about.

Edited by caffeine, : No reason given.


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caffeine
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Posts: 1702
From: Prague, Czech Republic
Joined: 10-22-2008
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Message 634 of 1362 (851731)
05-01-2019 1:32 PM
Reply to: Message 631 by FLRW
05-01-2019 12:28 PM


Re: Progressive Creation
The Ediacaran animals disappear from the fossil record at the end of the Vendian (544 million years ago). In their place we find representatives of almost all the modern phyla recognized today: sponges, jellyfish and corals, flatworms, mollusks, annelid worms, insects, echinoderms and chordates, plus many "lesser" phyla such as nemertean worms. These "modern" organisms appear relatively quickly in the geological time scale, and their abrupt appearance is often described as the "Cambrian explosion" however, bear in mind that the fossil record of the "explosion" is spread over about 30 million years.

Having just been doing some reading about Cambrian fossils (to make sure my correction of Dredge was actually accurate), I have a few nitpicks with the above.

Flatworms are not known from the Cambrian - flatworms have almost no fossil record at all (presumably because they don't fossilise well).

Molluscs, sponges, annelids and echinoderms may all have pre-Cambrian representatives (but all are controversial cases where the identification of the fossils is not clear).

Insects are terrestrial organisms that don't appear until much later, in the Silurian.


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caffeine
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Posts: 1702
From: Prague, Czech Republic
Joined: 10-22-2008
Member Rating: 2.9


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Message 641 of 1362 (851753)
05-01-2019 3:11 PM
Reply to: Message 636 by FLRW
05-01-2019 2:02 PM


Re: Progressive Creation
A team of scientists from Spain and the UK has determined that a certain curiously primitive group of flatworms are the oldest living ancestors to all "bilateral" animals-that is, those with a right and left side

That's a typically appalling journalistic mangling of evolutionary concepts. Things that are living today are not our ancestors.

What the article you're quoting is referring to is the new animal phylogeny that's developed over the past couple of decades, in which the basal split in living bilaterian animals is between a small group consisting Xenoturbella and acoelomate 'flatworms' (inverted commas to indicate that Acoela are not closely related to most flatworms); and a big group consisting of everything else. They are making the plausible but unevidenced assumption that the common ancestor was more like the acoelomates than the 'everything else'. In reality we don't know if that's true - acoelomates could represent a simplification of the ancestral body plan, rather than an unchanged, living example. Lots of organisms once considered to be primitive due to their simplicity have turned out to be nested within more complex organisms (like Trichoplax in the case of animals).

These worms were previously thought to belong to a much younger group of organisms, and their newfound identity also implies that bilateral organisms began making their debut on Earth earlier than previously thought.

The idea that this changes the dating is based on the divergence time estimates they found between acoelomate flatworms and other bilaterians - not because they found fossil flatworms.

I'm not arguing that there were no flatworms in the Cambrian. There probably were things we would call flatworms if we were looking at them today. I'm just saying there are no fossils. This is not just true of the Cambrian - there are basically no flatworm fossils at all - they just don't fossilise well. I think this was the central point of another post earlier in this thread.


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caffeine
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Posts: 1702
From: Prague, Czech Republic
Joined: 10-22-2008
Member Rating: 2.9


Message 643 of 1362 (851757)
05-01-2019 3:35 PM
Reply to: Message 639 by Tanypteryx
05-01-2019 2:47 PM


Re: Progressive Creation
Just to be clear, the flatworms you guys are talking about Genus Planaria, Phylum Platyhelminthes, correct?

There are loads of genera of Platyhelminthes, not just Planaria.

What FLRW was quoting was an article about the realisation that Platyhelminthes of tradition is not monophyletic - it forms two distinct clades. Most Platyhelminthes (including Planaria) belong in the same part of the animal family tree as molluscs and annelids. Some of the more primitive-looking flatworms (the 'Acoela', so named because they lack a coelom - the main body cavity of bilaterians where the important organs are all housed) turn out to not be Platyhelminthes at all. They don't belong to any of the three main groups of bilaterians, but are the first bilaterians to branch off from the others.


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caffeine
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From: Prague, Czech Republic
Joined: 10-22-2008
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Message 682 of 1362 (851840)
05-03-2019 4:17 AM
Reply to: Message 676 by Dredge
05-03-2019 3:29 AM


Re: Progressive Creation
The Ediacaran fossils were a “precursor“ to the Cambrian, but they can hardly be described as a “link” - there are no fossil links between E and C. For example, where are the links between the Ediacaran organisms (worms, sponges, barnacles, jelly fish) and the fish that appeared in the Cambrian? Ditto for Ediacaran life-forms and insects. My scientific explanation is that aliens took the Ediacaran creatures, seriously fiddled with their DNA and voila!... welcome to new and improved creatures of the Cambrian!

"BSTs (Burgess Shale Types) from the latest Ediacaran Period (eg, Miaohe biota, 550 Ma) are abundantly fossiliferous with algae but completely lack animals, which are also missing from other Ediacaran windows, such as phosphate deposits (eg, Doushantuo, 560 Ma)" - Daley AC, Antcliffe JB, Drage HB, Pates S 2018. Early fossil record of Euarthropoda and the Cambrian Explosion. PNAS, 9 pp.

It's fascinating to watch you at work. You tell us there are no links between Cambrian and Ediacaran fossils. Then in the next sentence you tell us that lots of Cambrian animal groups are found in the Ediacaran. Then to back up your claim you point us to an article arguing there are no animal fossils in the Ediacaran.

No wonder aliens seem the most likely explanation.


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caffeine
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Posts: 1702
From: Prague, Czech Republic
Joined: 10-22-2008
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Message 713 of 1362 (851942)
05-04-2019 3:18 PM
Reply to: Message 708 by Faith
05-04-2019 10:42 AM


Re: Restating the question
Hi Faith,

I have to start first with a nitpick, since unfortunately I'm a pedant and can't help it:

So it would be with the Triassic rodent AZ mentioned in Message 669. It would produce only variations on the rodent into the distant future, with superficial variations that don't change its basic character as rodent.

The 'rodent' you and AZPaul are talking about never existed. 'Rodent' does not mean generic, small, furry thing. Rodents are a specific group with many unique features - of which the most distinctive and well known are their continuously growing incisor teeth (that's where the name comes from - rodent comes from the Latin word for gnawing; since that's exactly what their teeth are good for). Nor are they necessarily small. The largest living rodents are bigger than most dogs; and the largest extinct rodent that's been discovered may have been the size of a bison. There are no rodents in the Triassic, and being a small furry creature does make one 'rodent-like', regardless of what journalists might say.

That out of the way, let's get to your actual point.

This is all another attempt to define the question I've been asking. How do you get from the genome of one species to that of another considering that each genome is a blueprint as it were for only the traits of the species it belongs to?

I think you're still mislead about what genes do. As I have explained previously, there is no gene for making hands. Genes make proteins, and out of those proteins organisms are built. You were talking before about chimp hands and human hands - so let's look at the proteins these are built out of. You may or may not be surprised to discover that they're exactly the same. Human and chimp skin are made out of the same proteins (mostly collagen, keratin and melanin). Human and chimp nails are made out of the same proteins - mostly keratin. Human and chimp muscles are made out of the same proteins (mostly actin and myosin). Bone is mostly made of hard minerals rather than protein, but these too are exactly them same in humans and chimps - it's mostly hydroxyapatite; while the soft part of the bone; constructed of proteins, is primarily collagen, again in both humans and chimps.

The point here is that all the materials used to produce a chimp hand are synthesised by the human genome. All of them - without exception. And vice versa - all the materials used to produce a human hand are synthesised by the chimp genome. We are made from identical materials - so there is no need for any new genes to go from one to the other.

Obviously, there's a bit more to it than this, otherwise why would chimp and human hands be different? We both have the same genes producing the same proteins, but it's not like everything is just thrown together and mixed up in the hope of producing a hand. There are other part of the genome that regulate the expression of the different protein-synthesising genes. That is, they make different genes 'turn on' or 'turn off' in different places of the body at different stages in development. This means that different proteins are made in different combinations at different times and parts of the body, all of which leads to the creation of organs and body parts.

This is what things like HOX genes are for. HOX genes would not be relevant for the difference between a human and chimpanzee hand - I mentioned them earlier only because they are one of the most well-known families of regulatory genes. HOX genes are involved specifically in regulating how ectodermal tissue develops differently depending on what body segment it's in (so they make your head look different than your bum and your arms look different than your legs). But there are many, many other families of regulatory genes involved in making genes express differently throughout the body.

And that's all that's needed to make a hand develop into a chimp hand instead of into a human hand. At the early stages of embryonic development the two would be totally indistinguishable. Actually look at the two side by side (the third hand is an extinct species):

These two things are not different in kind - there are just differences in relative size and shape. The bone, remember, is identical in chemical composition. As you can see above - the number and shape of the bones are also basically the same. All is takes is a slight variation in differential growth at different points in the hand to make this slight change in shape. And that just needs certain regulatory genes to be slightly different, so that they cause a particular protein to be produced in slightly bigger quantities in one hand than in the other.

And remember that it's not just the bone that's the same - the skin, blood vessels, muscles, nerves, hair etc - it's all made of the same stuff in humans as in chimps. All you need is slight differentiations in relative growth. Exactly the same mechanism that can make the different shapes and sizes of dog. What barrier are you seeing here that makes this an unacheivable change?


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caffeine
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Posts: 1702
From: Prague, Czech Republic
Joined: 10-22-2008
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Message 761 of 1362 (852047)
05-06-2019 1:32 PM
Reply to: Message 718 by Faith
05-04-2019 11:00 PM


Re: Restating the question
Also it seems to me that comparison of hands doesn't have the proportions right. Aren't chimp hands much larger?

No, I don't think so. It would depend on the individual. The picture I posted shows all hands scaled to the same size in order to show the different proportions more clearly.

Yes this explains how a human genome makes these differences in the human body, or a chimp genome in a chimp body, but it says nothing about how you could ever get a human trait from a chimp genome.

It's the same process. Just as the same genes can be regulated to produce different structures at different parts of the body, so they can be regulated to produce different structures on different bodies.

I used chimp because caffeine used chimp, not because I don't know the ToE drill.

It was you who raised the impossibility of turning a chimp hand into a human hand. I wouldn't have thought of such an example in relation to the request for how to form a completely different kind of structure, since you're the only person who thinks human and chimpanzee hands are different kinds of structure.

There are plenty of genes that are actually defined by the trait they build, and researchers are always identifying genes by the particular traits they produce, for various reasons including studying how to deal with genetic diseases.

There are no (or, at least, few) genes for a particular trait. What's going on here is two things - firstly, bad reporting. When a newspaper says 'Scientists discover the gene for x!' it's not true. This is just newspaper editors struggling to understand a complicated concept (or not trying to understand it, and going for cheap, sensationalist headlines).

Second, genetics is really complicated. If geneticists report discovering an effect of a gene, it doesn't mean they've identified the trait this gene is for. It means just what I wrote - they've identified an effect. I explained this to you before - OCA2 is often discussed as a gene for eye colour; but all this means is that geneticists found out the gene has an effect on eye colour. As I pointed out previously, this gene is expressed, amongst other places, in ovaries and intestines - it's not doing anything to do with colour there.

Funnily enough - I was just reading in the news someone discussing this idea in the context of 'designer babies', pointing out that we're not actually capable of making them.

quote:
If anybody thinks we can understand how to change genomes to improve things, they don't have an appreciation for the lack of knowledge that we have

You may think this is just a copout; but if, instead of a step-by-step account, you want just an idea of the general types of changes needed, that we can do. In fact, that's what I thought I'd already done, but clearly failed.

Consider again what we're trying to achieve. This is the hand of a human embryo at about 7 weeks:

At the equivalent stage of development, the chimpanzee embryo would look exactly the same. Chimps and humans will develop the same tissues, and the same type and number of bones in the same places, so we don't need to consider any big changes there.

All that we need for the above to take on a human or a chimpanzee shape, is for the different parts to grow at different speeds.

And this is of the things regulatory genes do. I mentioned them before turning different genes on or off at different parts of the body; but it's not really that binary. They 'upregulate' or 'downregulate' genes, which means they'll make them more or less active at different points. That's already what they do within different parts of the same organism - different regulation depending on the location of the hand is what makes the thumb grow to a different size, shape and orientation than the other fingers. If you take the regulatory genes which are causing the thumb to grow differently, and change them - causing them to activate genes earlier or later; upregulate some more, or downregulate others more, then that growth pattern will change.

I can't tell you exactly which genes, since we don't know (and by 'we' here I don't mean EvC - I mean humanity - I did a bit of reading and the genetics involved in patterning the hand are not well understood). But the basic process of making different parts grow at different rates in no different than that which produces different breeds of dog. There's nothing in the human hand that's not in the chimp hand; it's just a matter of changing the relative size and position of the bits.

Now, I don't really know if this answers your question, since I'm having difficulty fathoming your position. Clearly you're not satisfied with simply changing shapes, since you assert.

You will never get even a human fingernail from the chimp genome

Chimpanzee and human fingernails are almost identical. The precise amino acid sequence of human and chimp keratin is a little different, but only a little, and here we probably could give you the exact mutations necessary. All you need to do is download the protein sequences for human and chimpanzee keratin; look at the compositional differences, and then list some hypothetical point mutations that could cause the different sequence. If we really wanted to, we might not need to stick at hypothetical, since the human and chimp genomes have been published. It's theoretically possible for us to track down the specific genetic changes responsible. I'm not going to do that, since I don't see what value it would have. Similarly, you ask

How do you turn chimp skin and fur and nails into human skin and nails?

And, again, that we could do, since they're made of the same proteins with slight differences in sequence. Scientists figured out the genetic code long ago; we know the requisite mutations to account for specific changes in protein sequence. Is this really what you want to see? Below is the first 60 amino acids in human and chimp KRT5 ( a type of keratin). As you can see, the only difference is at position 52 (bolded), where chimps have glycine and humans have alanine.

MSRQSSVSFR SGGSRSFSTA SAITPSVSRT SFTSVSRSGG GGGGGFGRVS LGGACGVGGY
MSRQSSVSFR SGGSRSFSTA SAITPSVSRT SFTSVSRSGG GGGGGFGRVS LAGACGVGGY

Would it help your understanding for me to look up the genetic code and list point mutations that could change glycine to alanine, or vice versa? Because I doubt this is getting to the heart of your misunderstanding. What do you think are supposed differences between chimp and human hair, or nails, that can't be accounted for by this kind of tedious exercise?

Edited by caffeine, : No reason given.

Edited by caffeine, : No reason given.


This message is a reply to:
 Message 718 by Faith, posted 05-04-2019 11:00 PM Faith has responded

Replies to this message:
 Message 762 by Faith, posted 05-06-2019 4:42 PM caffeine has not yet responded
 Message 799 by Faith, posted 05-06-2019 11:06 PM caffeine has not yet responded

  
caffeine
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Message 817 of 1362 (852146)
05-07-2019 3:52 PM
Reply to: Message 813 by Faith
05-07-2019 2:41 PM


Re: Restating the question
Hi Faith,

I'm still mullling over how to respond to your general point, since I'm having trouble getting my head around what you understand a genome to be. But while I'm mulling I felt obliged to respond to this one, since it's more to do with your understanding of chimpanzees than your understanding of genomes.

Give me a rodent ear or a chimp's fingernail on a human being.

If a human grew a chimp's fingernail, how would anyone even notice? Have you ever seen a chimpanzee's hand? Chimp fingernails are exactly the same as ours. What distinguishing features do you see, bearing in mind that (for no clear reason) colour variation doesn't count by your own conditions:


This message is a reply to:
 Message 813 by Faith, posted 05-07-2019 2:41 PM Faith has not yet responded

  
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