What Are Your Favorite Arguments For Evolution?

You continually boast about the fossil record supporting your claim of gradualism. Let’s stay with that thought for awhile.

Where are the ancestors of the Cambrian?

[edit: do not give me a book to read]

If you won’t even read it, how can you know? The pre-explosion record is poorly preserved relative to the amazing, rare Lagerstätten we find at the end of the Early Cambrian and the Middle Cambrian. But there’s enough to tell us something about the situation. Just try the book. If you’re getting all your information from creationist sources you are missing out on the real facts.

“The Cambrian” has a 25-million-year history preceding what you think of, trilobites and such. And before that there’s the Ediacaran fauna. During that time, there’s a gradual buildup in variety and complexity of trace fossils such as tracks and burrows, and also of what’s called the “small, shelly fauna”. And of course there’s the molecular data.

If you won’t read a book, you won’t learn much.

4 Likes

He did not claim gradualism.


@noUCA the goal here is to understand and to be understood? What are you learning about the positions with which you disagree?

4 Likes

That they are ill supported.

I hear you. My time is short. It will doubtless be soon.

You are confused about something much more basic that evolutionary biology here. All scientific conclusions are based on inductive reasoning. We create models for physical reality and then test them. Inductive reasoning is not deductively sound. If you wish to reject all scientific conclusions that are lack deductively sound arguments, you are free to do so – go live in a cave and reject all of science. But if you do accept any science, then don’t raise objections to evolution that apply to the whole enterprise.

Of course. Now all you have to do is offer one of the many other reasons that genetic differences should show the patterns they do.

As has already been pointed out, the answer is no. Because you also have to explain why humans and chimpanzees are equally different from gorillas, with the differences showing the same pattern as before.

3 Likes

4 posts were split to a new topic: Introducing no UCA

Then it would seem that you reject the scientific method as a whole since that is exactly how the scientific method works.

Hypothesis. Test hypothesis. Observations match hypothesis, and do not match null hypothesis. Hypothesis supported. This is science.

Every single natural phenomenon could be explained by a supernatural entity exactly mimicking a natural process. This is where the George Romanes quote comes in:

3 Likes

I see that some of our resident creationists have fallen back on the “God could have created it with the appearance of age”-rationalization. This time the rationalization is just about the genetic differences between species being consistent with biochemistry.

There is no conceivable observation that could me made, that could not be rationalized as what God wanted to create. If a scientific theory is supposed to be able to disprove such a rationalization before being genuine evidence for the theory, then it is impossible to gather evidence for any scientific theory.

I think you have to wonder, though, why God would go to such great lengths to make it appear like common descent occurred.

3 Likes

Pulling yet another quote out of my bin . . .

Phillip Gosse wrote the infamous book “Omphalos: An Attempt to Untie the Geological Knot” in 1857 where he argued that God created the Earth with the appearance of age. That didn’t go down well with the christian clergy of the time:

3 Likes

I’ve already offered one (see below for more details)

Ok. Let me try to explain my idea/model in more details.
First, I imagine the special creation in the distant pass (let’s say 10 millions years) of some ancestor of ape like creatures such as gorilla and chimpanzees. Let’s called this ancestor GOCHI.
I also imagine the special creation of human much more recently, let’s say about 10 thousands years ago.
Now, let’s see for a given gene, for example myoglobin, what we would expect to see in terms of genetic differences between the 3 species, i.e., human, gorilla and chimp.
Before answering the question, I have still to clarify the following point: I posit that the 2 myoglobin genes at the time of their creation in GOCHI and in humans were nearly identical, the only differences resulting from some designed fine tuning to accommodate for the physiological differences between ape like creatures and humans.
Now, given the above model, let’s go back to our question: how the genetic differences of the myoglobin gene between human, gorilla and chimps would look like today. The answer is straightforward. Because the 3 myoglobin genes would have evolved by random mutations from nearly the same template, the vast majority of these differences would look like mutations, exactly as with CD.
Moreover, note that under my model, we would also expect humans and chimpanzees to be equally different from gorillas.

Is this to say that you see these species as fixed in time? As in, there are humans, chimps, and gorillas and that there are not many, many iterations of each in between? The species are static, not dynamic? Just trying to understand.

So the human DNA today looks nearly the same as the originally created GOCHI DNA, since humans have added very few mutations since their creation, right? (We’ll leave aside the difficulty that humans have a couple of million years of mutations accumulated as genetic variation within their current population, at least for the moment.) In this scenario, chimpanzees and gorillas will look equidistant from humans (with the pattern expected from mutational accumulation), and will be nearly twice as distant from each other as they are from humans, since each has accumulated lots of independent mutations while humans haven’t. That looks nothing like the real situation.

6 Likes

@Giltil, I want to point out that @glipsnort is taking your hypothesis seriously, working out what the evidence would show if it were true. He is then showing that the evidence does not show what we would expect under your hypothesis, and therefore rules out your proposal.

He is engaging your objections, and testing your hypothesis. You are being taken seriously.

5 Likes

Just so we have some numbers to work with . . .

I could have messed this up, but these are the alignment scores I got for the myoblogin gene in these three species (using Ensmbl to get alignment sequences and Kalign to get matrix) :

            Human      chimp         gorilla
Human       100         98.06         96.1
Chimp       98.06       100           96.59
Gorilla     96.1        96.59         100

There is about the same distance between chimp and gorilla as there is between human and gorilla, and humans are closer to chimps than gorillas. This is not what we would expect from @Giltil scenario.

4 Likes

Yes, I think that species are ontologically fixed when they are differentiated, as cells are in their differentiated states. But I believe that some archaic undifferentiated organisms in the past were able to give rise to more differentiated species, as stem cells can give rise to more differentiated cells in living organism.
IOW, I would propose that in the grand scheme of life, some undifferentiated and archaic organisms in the past have functioned somewhat as stem cells in the development of individual organisms, giving rise to many different more differentiated organisms. And maybe it is these archaic stem like organisms that were specially created.

1 Like

Differentiation of cells does not involve mutations or changes to the genome (except in some rare situations, e.g. immune cells). The mechanisms involved in differentiation of cells are totally unlike that which would be required to form new species.

1 Like

What physiological differences relevant to myoglobin? How would those differences conceivably cause differences in intron sequence?

No, we would expect humans to be equally different from chimpanzees and gorillas, since the latter two share a common ancestor not shared with humans. We would also expect humans to be much, much more similar to the template than either. Instead we see humans and chimps sharing a common ancestor not shared with gorillas, and about equally far from that ancestor. We don’t expect the supposed fine-tuning to follow the same distribution of differences as mutations would. I should also point out that around 15% of genes show chimps + gorillas and another 15% show humans + gorillas, inexplicable under your scenario. And around 1.6% show one of the three closer to orangutans, again inexplicable under your scenario. Yet it’s expected under common descent then there are reasonably sized populations and a short interval between speciations.

1 Like

Just to clarify: this is the gene including introns and, likely 5’ and 3’ untranslated regions, right?

It would appear so. I went to the human myoglobin page at Ensembl and chose the alignment with 13 primate EPO species. The ancestral sequences are included in the alignment if anyone is interested. The FASTA output is pretty large, so I assume the introns are included.

This is easily shown to be false as we observe new mutations happening in all species. They continue to diverge, both from each other and their common ancestor.

This would require the original individuals of that population to stay alive and keep reproducing through millions of years. As soon as you have generations then you inevitably start accumulating mutations and changing that population.

2 Likes