SCD's Questions about Sponge Genomes

its seems that the globin complexity is basically the same in both primitive and modern creatures (at least for myoglobin):

so where is the evolution actually?

(image from PDB-101: Molecule of the Month: Globin Evolution)

What do you see in this figure that suggests that globin complexity (it might be helpful to define what you mean here, as well) is “basically the same in both primitive and modern creatures”? Each of these drawings is from a modern creature.

indeed. but this is after the fact explanation. we can check it at the genomic level too. we know for instance that some of the most ancient creatures (sponges for instance) had a genome that is no less complex from that of a modern creature (human for instance). so the most primitive creatures are no less complex than modern creatures.

Sorry, but the only sponge genomes you know about are modern sponges, which are not ancient at all. In order to make any inference about ancient sponges, you would have to make use of phylogenetic inference. But you reject that, so you can’t really say anything about the subject. Your claim also suffers from the equating of genomic complexity with phenotypic complexity; it seems you are unacquainted withe the c-value paradox.


Sponge genome sizes vary 17-fold, so yeah…


“Nevertheless, 18,693 (63%) have identifiable homologues in other organisms in the Swiss-Prot database”

so the ancient sponge gemome was not so different from the modern version.

for the moment we are talking about genomic complexity. so the bottom line is that the most primitive creatures on earth have basically the same genomic complexity as modern creatures.

As I said, that inference relies on phylogenetic analysis, but you reject the idea of phylogeny. You can’t come to that conclusion. You don’t even believe that life has a long history.

Then you have just changed the subject. Try at least to notice when you do.

Again, you have access only to modern creatures, so this claim makes no sense. Also, different species have different amounts of “genomic complexity”, with no particular pattern.


irrelevant since in any case (creation or evolution) sponge has similar complexity to modern creatures.

that not true.

Sponges are modern creatures, so that’s more word salad.

It says “YEC” in your title. Is that not true?

i refer to the ancient sponge. i dont think that evolution predict that some of the most ancient creatures had similar genomic complexity to modern creatures.

not necessarily. i said it several times before. i didnt choosed my title.

Why don’t you think that? Where did the “genomic complexity” come from, if not from more ancient creatures? I don’t see anything in evolutionary biology or in any of your comments to justify making this claim. To make a contribution to a discussion of “genomic complexity” and its evolutionary history, you would have to engage phylogenetics.

But you can have no idea what the genome of an ancient sponge looked like, especially since you reject phylogenetics.

What you think or don’t think has no necessary relationship to reality. And you can’t know anything about the genomic complexity of the most ancient creatures. (Other people might, but you are prevented by your rejection of all evidence.)

What exactly does that mean? If your title is inappropriate, change it to something better. And if you would actually explain what you believe for once, you wouldn’t have probems like this. So, do you think the fossil record correctly shows billions of years of the history of life?


im saying that the level of genomic complexity (number of genes) dosnt fit well with the geological time. evolution suppose to predict that complexity evolve stepwise. in reality we find that the first creatures were already complex like modern creatures. unless evolution has no prediction at all about that and in this case i cant see why to call it a scientific theory.

how? i see no such option in the menu.

probably yes.

But you’re not saying why you think this. It’s okay. I know there’s no reason to think this. There’s really nothing to discuss.

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You have to ask a moderator.

Why “probably”?

I just have to say that it’s unfortunate that discussion of this fascinating and important research has to be derailed by people who have a sub-grade school understanding of science, who refuse to acknowledge this and have no interest in learning. There are experts in this group from whom we could learn much, but their time is taken up responding to nonsense. I don’t know what, if anything, can be done about this situation.



Yeah, it’s pretty discouraging. It’s rare to see discussion of actual science here at PS, and it is almost always interrupted by ignorance and worse. One part of the problem is a moderation team that is passionate about comments involving Celtic gods but oblivious to the incessant insertion of nonsense into scientific discussions. I’m staying for now but mostly because I will always have low expectations of conversations with believers. Sad to say.


I agree and suggest a @moderators split.


this is a simple prediction by the evolutionery theory. if complex creatures evolved from simpler creatures then we should find that hierarchy. but we dont realy find that.

Restating these inaccurate claims is a waste of time. You are wrong, and you don’t understand the topic.