[_ Old Earth _] Just curious..

[lordkalvan]

Um, 'zero science' again there, Barb. ;-)

 

[Sparkey]

I'm one of the "lurkers" in this thread and I thought I'd pop in to try (wish me luck) to help with the Gould homology quote aspect of the discussion.

The lordkalvan quote about "homology proving common descent, period" is readily found with the reference being, Gould, S.J., The heart of terminology, Natural History 97(2):26, 1988.

I've seen reference to the "secondary source" quote by zeke being the same source, Natural History, but from 1967 and could provide it if there was need.

The quote is part of the larger question: "How can Darwin's hypothesis of 'descent with modification' be confirmed or denied? Evolutionary biologists often propose Darwin's own definition that ties homology to embryonic development for the determination. In Origin of the Species, he defines 'homology' as "the relation between parts that results from their development from corresponding embryonic parts." The assumption behind his logic (in light of modern science) is that "corresponding embryonic parts" are themselves controlled by homologous genes.

The first time I head the phrase, "Ontogeny recapitulates phylogeny," was when I was in the 5th grade (back in the 1960's). The suggestion then was that adults go through the evolutionary process from fish to reptiles and eventually to human during the embryonic process. This "process" was never established by evidence and was discarded.

The concept of homology as evidence continued and has been largely accepted. According to "Darwin on Trial," Gould recalls the concept of ontogeny and phylogeny being linked taught to him in school, fifty years after it had been discarded. Reference: Darwin on Trial

 

[Free]

Just a note to say that the personal attacks had better stop or this thread will get locked and infractions issued if necessary.

 

[Barbarian]

Sparrowhawke writes:

The first time I head the phrase, "Ontogeny recapitulates phylogeny," was when I was in the 5th grade (back in the 1960's). The suggestion then was that adults go through the evolutionary process from fish to reptiles and eventually to human during the embryonic process.

I cringe to think of that. We still have poor science teachers, but hopefully fewer these days. That was not Darwin's position, but a distortion of if proposed by Haeckel whose theory of recaptulation has been decisively refuted. Opossums show an early stage in which they have the reptilian jaw (which later changes to the mammalian one, with the excess bones going to the middle ear) not because they become reptiles at one stage, but because embryonic development is constrained by what went on before.

The concept of homology as evidence continued and has been largely accepted. According to "Darwin on Trial," Gould recalls the concept of ontogeny and phylogeny being linked taught to him in school, fifty years after it had been discarded. Reference: Darwin on Trial

Embryology can teach us much about the evolution of animals, but it does not show recapitulation of ancient taxa. For example, we have branchial arches in our embryonic state, as fish do, but they never become gills; instead they become jaws, ears, etc.

Old things, modified to new uses. It's what evolution does.

 

[Barbarian]

Just a note to say that the personal attacks had better stop or this thread will get locked and infractions issued if necessary.

Noted. I will try to do better.

 

[zeke]

I've seen reference to the "secondary source" quote by zeke being the same source,*Natural History, but from 1967 and could provide it if there was need.

Actually, the primary source is noted as January 1987.

The first time I head the phrase, "Ontogeny recapitulates phylogeny," was when I was in the 5th grade (back in the 1960's). The suggestion then was that adults go through the evolutionary process from fish to reptiles and eventually to human during the embryonic process. This "process" was never established by evidence and was discarded.

You may be referring to the Darwinian sleight of hand artist and evolutionist, Ernst Haeckel whose fraudulent embryological drawings were exposed back in the 19th century but can still be found in recent biology textbooks. Darwinian mythology dies hard but its practitioners must periodically rely on such fraud to stay afloat. See the Piltdown Man hoax.

 

[zeke]

If you imagine this is a reasoned refutation of Barbarian's several points, that would be the only sad thing here.

Well, I don't want to be accused of making personal attacks but maybe you can decipher Barbarian's "several points" as noted below and how they relate to science in general and biological evolution specifically. If early tetrapods really needed to run both tendons down to their feet as Barbarian insists how did they kinda/sorta come up with a plan to do that type of plumbing? Where did the tendons run before they figured out how to route then to their feet? Scientifically, can we really draw a sequential line between early tetrapods and carpal tunnel syndrome in humans? Is that hypothesis testable?

Barbarian
That would be demonstrated by the bones being specifically organized for each function, not modified to kinda/sorta do it. For example, our hands are prone to carpal tunnel damage and subsequent disability, because the early tetrapods needed to run both the tendons and the radial nerve down the same channel to make the feet set correctly.

 

[zeke]

Um, 'zero science' again there, Barb. ;-)

Okay - how about fuzzy science?

 

[zeke]

It means the HOX genes for limbs show a common origin for all tetrapods.

And what keeps that 'common origin' from being a "common designer" who "used successful design principles over and over again�

 

[zeke]

Please explain what you understand by 'biological evolution' and 'Darwinian lore' and how the two differ.

In a nutshell - biological evolution is science and Darwinian lore is mythology. The former is science - the latter is non-science.

 

[Barbarian]

Lord Kalvan asks:

Please explain what you understand by 'biological evolution' and 'Darwinian lore' and how the two differ.

Zeke writes:

In a nutshell - biological evolution is science and Darwinian lore is mythology. The former is science - the latter is non-science.

I'm kinda surprised. Zeke clearly doesn't know what Darwinian theory says, and he always dodges any questions about it. It would seem like a simple thing for him to spend a few hours and just learn what it is, but for some reason, he isn't willing to do that.

 

[Barbarian]

Barbarian observes:
It means the HOX genes for limbs show a common origin for all tetrapods.

And what keeps that 'common origin' from being a "common designer" who "used successful design principles over and over again�

A competent designer wouldn't use a design that was suitable for a tetrapod, to make a biped. Humans have a great deal of trouble with lower backs, hips, knees, and feet because those structures are only partially adapted to an upright posture and frequently fail. Pretty much like the carpal tunnel, which was not at all a problem for an organism walking on forelegs, but a huge problem for an organism that frequently and forcefully uses grip and wrist deviations.

These structures are cobbled-together structures, adapted from earlier forms, that are still prone to many problems. It would be easy to design out the back problems many people have, just by rerouting spinal nerves. But that's an intrinsic part of the axial nervous system and would have to be completely redesigned. And we never see that in nature.

 

[zeke]

Lord Kalvan asks:


Zeke writes:


I'm kinda surprised. Zeke clearly doesn't know what Darwinian theory says, and he always dodges any questions about it. It would seem like a simple thing for him to spend a few hours and just learn what it is, but for some reason, he isn't willing to do that.

Well - you will need to define your term - what do you mean by "Darwinian theory". Are you referring to the ToE or the Darwinian speculation you and others are using on this thread? I am well acquainted with both.

 

[zeke]

A competent designer wouldn't use a design that was suitable for a tetrapod, to make a biped.

Where is your science to support your assertion? Got any?

Humans have a great deal of trouble with lower backs, hips, knees, and feet because those structures are only partially adapted to an upright posture and frequently fail.

Many humans don't have a great deal of trouble with lower backs, hips, etc. Are they descended from another common ancestor than those who do?

Pretty much like the carpal tunnel, which was not at all a problem for an organism walking on forelegs, but a huge problem for an organism that frequently and forcefully uses grip and wrist deviations.

Scientifically, can you draw a sequential line between early tetrapods and carpal tunnel syndrome in humans? Is that hypothesis testable? You do know what testable means?

These structures are cobbled-together structures, adapted from earlier forms, that are still prone to many problems. It would be easy to design out the back problems many people have, just by rerouting spinal nerves. But that's an intrinsic part of the axial nervous system and would have to be completely redesigned. And we never see that in nature.

And your assertion proves common ancestry - how?

 

[Barbarian]

Well, I don't want to be accused of making personal attacks but maybe you can decipher Barbarian's "several points" as noted below and how they relate to science in general and biological evolution specifically. If early tetrapods really needed to run both tendons down to their feet as Barbarian insists how did they kinda/sorta come up with a plan to do that type of plumbing?

No planning necessary. These features are already present in the fish that gave rise to tetrapods. In primitive amphibians, the various flexor tendons already run through the carpal tunnel with the median nerve. But they aren't very robust, and there's plenty of room. And of course, the forces aren't that great in tetrapods, which don't grip much.

Where did the tendons run before they figured out how to route then to their feet?

Turns out the nerve existed in fish before feet. A branch to the fins of lobed-fin fish existed, and that persisted in tetrapods.

Scientifically, can we really draw a sequential line between early tetrapods and carpal tunnel syndrome in humans? Is that hypothesis testable?

Yep. The median nerve, with the flexor tendons, is trapped within a tunnel formed by the carpus and the transverse carpal ligament. The relatively large and frequent forces humans put on the tunnel tends to inflame it. Tetrpods don't normally exert gripping forces; the ones that routinely grip and manipulate are normally smaller than humans, with proportionately lower forces.

 

[Barbarian]

Barbarian observes:
A competent designer wouldn't use a design that was suitable for a tetrapod, to make a biped.

Where is your science to support your assertion? Got any?

Sure. Humans have a great deal of trouble with lower backs, hips, knees, and feet because those structures are only partially adapted to an upright posture and frequently fail.

Many humans don't have a great deal of trouble with lower backs, hips, etc.

But many do. They do, because of the inefficient and injury-prone nature of these structures in bipeds. Almost all of us, as we age, have back-related and knee-related problems. Likewise, hips are often a sources of pain, as are feet.

Barbarian observes:
Pretty much like the carpal tunnel, which was not at all a problem for an organism walking on forelegs, but a huge problem for an organism that frequently and forcefully uses grip and wrist deviations.

Scientifically, can you draw a sequential line between early tetrapods and carpal tunnel syndrome in humans? Is that hypothesis testable? You do know what testable means?

Yep. For example, we can show that the space in the tunnel is tightly restricted for humans, but not so for tetrapods, which have less robust tendons.

Barbarian observes:
These structures are cobbled-together structures, adapted from earlier forms, that are still prone to many problems. It would be easy to design out the back problems many people have, just by rerouting spinal nerves. But that's an intrinsic part of the axial nervous system and would have to be completely redesigned. And we never see that in nature.

And your assertion proves common ancestry - how?

This demonstrates that humans were not designed, but evolved from tetrapods, and retain the basic tetrapod anatomy, slightly evolved to a bipedal way of life. But it's not fully adapted, and that causes problems. A competent designer would never have done it this way.

 

[zeke]

There's a lot more. For example, the opossum fetus initially has the jawbones of a therapsid reptile. Only later do those bones migrate slightly back into the middle ear, as we see happening in the fossil record. Want to learn about that?

Are you making the claim that you can take a line of fossils from therapsid reptiles to opossums and claim that they represent a lineage?

“No fossil is buried with its birth certificate. That, and the scarcity of fossils, means that it is effectively impossible to link fossils into chains of cause and effect in any valid way... To take a line of fossils and claim that they represent a lineage is not a scientific hypothesis that can be tested, but an assertion that carries the same validity as a bedtime story—amusing, perhaps even instructive, but not scientific.†― Henry Gee, In Search of Deep Time: Beyond the Fossil Record to a New History of Life​

 

[zeke]

Barbarian observes:
A competent designer wouldn't use a design that was suitable for a tetrapod, to make a biped.

Again - do you have science to support your assumption.

Yep. For example, we can show that the space in the tunnel is tightly restricted for humans, but not so for tetrapods, which have less robust tendons.

Do you have science to support your assumption

This demonstrates that humans were not designed, but evolved from tetrapods, and retain the basic tetrapod anatomy, slightly evolved to a bipedal way of life.

Lol - humans evolved from tetrapods. Really? Do you have science to support your assumption. Does kalvan agree with you? Does anyone agree with you?

But it's not fully adapted, and that causes problems. A competent designer would never have done it this way.

Do you have science to support your assumption

 

[Barbarian]

Are you making the claim that you can take a line of fossils from therapsid reptiles to opossums and claim that they represent a lineage?

Well, let's take a look...

Here's a line of therapsids leading to primitive mammals. Notice that the bones of the reptilian jaw (except the dentary) are gradually reduced over time, until only the mammalian jaw remains. The smaller bones, which in the reptiles served as both jaw and sound-gathering structures, change over time to being only sound-gathering.

“No fossil is buried with its birth certificate.

But we can learn about the way populations change over time, by observing the changes in the fossil record.

So, I'll hand you a question a creationist dodged earlier. If I can show you a series of fossils in temporal order, in which differences between each adjacent one are less than we can see within many species alive today, will you admit that we can see lineages in the fossil record?

And if not, why not?

 

[zeke]

Question for kalvan - does your 'science' also demonstrate that humans evolved from tetrapods - slightly tweaked to a bipedal way of life?

Originally Posted by Barbarian
This demonstrates that humans were not designed, but evolved from tetrapods, and retain the basic tetrapod anatomy, slightly evolved to a bipedal way of life.