Evolution of fish to amphibians is there evidence of limbs growing from existing skeletal structure

I was reading a little about the evolution of amphibians from fish…in the image i saw i noticed that, as i have also read from some critics, that the earliest limbs do not appear to be connected to existing skeleton…the limbs are attached only to flesh.

Thats interesting…

  1. are the examples of fossils where the limb evolution is found attached to existing skeletal bones?
  2. Are there examples in current studies of skeletal animals where limbs are connected only to flesh?

Hi, can you please provide the citation of the article in which you saw the diagram? And the citation of the article in which people were criticizing it? It would provide a more solid base for discussion.


Actually, fore limbs (including scapula) of most mammals (opposed to humans and to hind limbs) are only attached to flesh. Look to a running cheetah. See how flexible the forelimbs are attached to the chest.
Some animals have, due to an embryonic developmental error an extra limb. At many times, these limbs are not connected to the central skeletal system.


Part of the issue is what “earliest limbs” are you talking about.

The earliest development of fins is folds of tissue, not skeletonized. However, the lobe-finned fish, which are most similar to amphibians, generally had a set of bones, corresponding to leg bones, in the stalk of the fin. (Of the living lobefins, five have rather reduced fins and two have largely cartilage skeletons, so “had” is referring to fossils.) As animals develop better ability to move on land, this typically goes along with increased strengthening of the limbs, though as pointed out above, flexibility can be useful as well.


Just so casual. The limbs just develop, in the right way, at the right time. Really?
Can you hear yourself?


Much of this adaptation would be just regulatory. Selective pressure is always under the environment existing at the time. So what I hear from David sounds fine to me.


Actually, the problem with my statement is not that it is implausible, but that it is practically tautological. Animals with better abilities to move around on land have better abilities to move around on land. The right time to develop something better is anytime, so timing is not difficult. Humans developed stronger hip joints for better bipedal walking and running almost 250 million years later than the first archosaurs did. And there are many different ways to improve limb function, in part because “improve” is extremely vague - a limb that is not as good for one thing can be better for another. Evolution is about “whatever works”; the “survival of the fittest” is a rather inaccurate phrase in most cases.


Hmm, tautology

a statement that is true by necessity or by virtue of its logical form:

The point is that evolution is always developmental as if improvement is inevitable. But the principles of aging and decay are the reverse of that.
Humans improve, not by evolution but personal ambition and to a greater or lesser extent glory (Olympic medals et al)
Natural Selection assumes competition. Competition only occurs if resources are not enough to support everything. When there is plenty competition will not be a factor. When life was still developing the ratio of animals to flora would mean plentiful supplies. Carnivores should not be necessary but, by all accounts, they existed virtually simultaneously. So there must be other forces at work.IOW the diversification has to be driven by more than just the environment.


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What is important for evolution is how many grandchildren you get. When you have passed your reproductive phase, it does not matter if you ‘deteriorate’ unless you can somehow affect the fate of your grandchildren. In humans, an active grandmother may often increase the wellbeing of their daughters and grandchildren, which may be one reason why women survive so long. Otherwise, aging and decay may be beneficial from the viewpoint of evolution because then you are not competing so much with your grandchildren.

How an individual ‘improves’ does not either matter, except if it affects the relative number of grandchildren. The word ‘relative’ is important because if you get two children and your neighbors one child, that is an influential advantage from the viewpoint of evolution. Even more so than if you get six and your neighbor four children.

Bloody competition for limited resources is not always the key issue in natural selection. Cooperation (mutualism) can be a more influential strategy because it may increase the amount of resources and reduce mortality. Also investing much to reproduction even at the cost of deterioration, starvation and early death can be beneficial. Natural selection is ‘blind’ in the sense that however you increase the relative number of grandchildren does not matter - whatever works is ok.

Because of the ‘blindness’ of evolution, evolution does not provide any foundation for what is right or wrong. Ethics must come from other sources.

one reason why I do not like that evolution is pictured as an important matter in the life of humans is that the number of grandchildren is not very important from the viewpoint of Christian beliefs. If we read the letters of Paul, he even recommends staying single. Reproduction has a significant cost and even marriage without children takes it share. A single person can invest in the matters of God, rather than using the time to please the spouse and spending the energy, money and time to raising children.


Also, there is the problem that evolution is often incorrectly presented as progress, generally towards humans. But simplifications and reductions are quite common in evolution. Because evolution is actually survival of the fit enough rather than the fittest, and because the real world has many constraints and interconnections, it is common for “improvements” to have downsides as well. As long as it works, organisms can survive. Over the long term, some organisms specialize in particular ways, and so there is directionality. The earth has inherently limited resources, though there is significant variation in the level of competition. But even if there is plenty, individuals with really bad conditions are likely to do poorly. This also tends to give a degree of directionality.


How common? I was under the impression that there is a tendency for greater complexity over time. Is that not true?

it is also easy to take your statement as meaning humans are just accidents which is atheism, not Christianity.


Thank you, those are important clarifications needed. Accepting that God is in control of evolution, one of the purposes that He has used it for is the creation of humans. But it is also used for creation of all other organisms. They are not trying to become more humanlike, but rather are simply doing whatever works for them. More broadly, this means that social policies supposedly based on evolution that seek to make humans “progress” are not true to the biology, but rather are an imposition of the goals of those with the agenda onto biological change.

Across the total of all organisms, there is an increase in complexity. This is not necessarily mathematically distinguishable from random, because life has a minimum level of complexity but not a maximum. Once you have life, if some are getting more complex and some less, the net effect is to have increasing maximum complexity. For example, a study looked at whether muricid snails had a tendency to get bigger and spinier over time. As the first ones were small and lacked spines, and many today are big and/or have spines, there is an increase in the average size and number of spines. But you can’t have fewer than zero spines, so some of this change is mathematically random. But if there is a way to make things less complex, organisms will often do that. Consider the extreme morphological simplification in many parasites, for example. If you can mooch off someone else for much of what you need, you don’t need to take care of that yourself.


That would be (not that you are) making the same mistake others here do, conflating the ‘VFB’ with the ‘VFA’ (initialisms elaborated upon here). (We could also talk about the provenance of providence. ; - )

How to reconcile God with Evolution and how not to.

so we accept there is revelatio from above in the Bible but how much? What is the model of inspiration that is correct? How coercive was God in dealing with the human authors? What method do we used to interpret scripture? What is the actual interpretation on any issue and how has it changed in the church over time? Is it accommodated? These are all from believe positions we have to take and they influence everything. Looks like it’s all from below no matter what we do. I’m not buying the distinction. Looks like a bad attempt at salvaging some form of inerrancy.

Not really. All it fundamentally says is that science can only deal with methodological naturalism. It doesn’t have access to @St.Roymond’s divine-o-meter™, yet to be released.


Yet another post showing you don’t understand evolutionary theory. The “right way” is the one that survives, and there is no “right time”. Limbs would develop in different ways but only what worked would be preserved.

This is incorrect. Competition occurs at all times whenever there is a predator-prey relationship Any mutations that allow prey to escape their predator will be beneficial whether there is plenty or scarcity, and the same is true of predators.

Good alternate description!

“Survival of the fittest” brings up the idea of nature “red in tooth and claw” and the silly idea that whatever doesn’t kill you only makes you stronger. A fair analogy would be that survival of the fittest means only the top ten percent of a school class get to move on to the next grade, while survival of the fit enough would mean that only the bottom ten percent don’t get to advance.

It’s a tool for clear thinking. But yes, there is some ambiguity; what the scriptures say is always view from above, but methods of interpretation tend to involve view from below. For example, exegesis will be VFA while eisegesis is VFB. And any time a human philosophy is being imposed on the scriptures it results in VFB; two good examples are YEC which imposes the idea from scientific materialism that to be true a thing has to be 100% scientifically and historically accurate, and transubstantiation which imposes Aristotelian/Platonic categories.

It has nothing to do with inerrancy at all; if anything it has to do with authority, i.e. that the scriptures are the only objective source designated as revelation then they have authority. And indeed considering the above, the view from above has to rely on what the original author intended to say and what the original audience would have understood within their worldview – which pretty much shoves inerrancy out the window since nearly all inerrancy actually rests on a foundation of thinking that scripture can be understood without studying anything except the scriptures, and those in one’s preferred language.

In terms of the whole point of BioLogos, yes, but in broader terms it has to do with any system of human thought being kept distinct from revelation. Another example comes to mind – the Immaculate Conception of Mary, which is the result of imposing human categories of “fitness” (i.e. appropriateness) onto the Incarnation.

Should it ever be invented, I think the label divine-o-meter would be shortened to “divinometer”.

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Neither of these claims addresses the question. An extra limb (embryonic error) in a 4 legged animal does not add to the animal’s ability…it drastically limits the animal’s ability…so that is not an improvement in any way!

A running cheetah example also doesn’t address this. the question… the muscles tendons and ligaments support skeletal structure whilst allowing work to be done. This is very different from useless apparent limbs hanging off flesh that couldn’t support anything on land.

such a view would suggest that a limb growing on flesh could do work without simply being torn off. I’m not a person who is familiar with all kinds of skeletal structures in animals, but aren’t limbs usually attached to major skeletal areas and eventually a spine?

I am after examples in the timeline showing the transition please…none have been posted yet that explain the transition between fish-amphibians-land creatures.

i also reject the notion that we even evolved from animals…Genesis specifically states that God created man in his own image. Animals were created in a separate statement.

If we are made in God’s image, then we follow the pattern of His own design.

To put natural selection into the creation story would mean God was not always what He is now, rather His own existence is via the same scientific mechanisms responsible for our development.

So, you also claiming God evolved from a fish!

This is another reason why evolution is incompatible with the Bible…God is not constrained by science…He doesnt need science for anything…hence the existence of miracles which are not scientific. Creation was a miracle…not science.

Yeah, divine-o-meter is so 1950s – vintage approaching antique.