Specifically, what is the evidence for common descent?(Not quite) famously, Darwin mused about the similarities of taxonomic hierarchies in linguistics and biology and asserted that the hierarchies must ultimately point to common descent. (Chapter XIV, On the Origin of Species) That’s common descent as distinguished from microevolution.
The linguistic equivalent is the single origin of all languages (eminently unproven and deemed unprovable) as distinguished from a language family (with demonstrable relevant organic shared features).
Darwinists are welcome to present their evidence. From Rumraket, we have the observation that all organisms can reproduce, “Nesting hierarchies are evidence of common descent if you know that the entities sorted into hierarchies can reproduce themselves. And that particular fact is true of all living organisms.” Good start.
From Joe Felsenstein we have the doubt that the border between micro- and macroevolution can be determined, “OK, so for you the boundary between Macro/Micro is somewhere above the species level. How far above? Could all sparrows be the same “kind”? All birds?” Not very promising.
From Alan Fox, “Darwin predicted heritable traits. Later discoveries confirmed his prediction.” Questions: Which heritable traits specifically? Was there a principled improvement over Mendel? And how does this lend credence to common descent?
Thanks to all contributors.
LMAO!
Japan.
Just look at UD and the DI, chock full of lawyers, engineers, and techies who are far better at biology than the biologists.
There’s a whole world of nails for their hammers.
Glen Davidson
Jackalopes and crocoducks.
Glen Davidson</a
Micro not macro growth.
That’s not a barrier. It’s merely pointing out what we already know, that speciation takes longer than one generation. The things you listed previously aren’t barriers either. They’re just more of the usual “we didn’t see it happen in the extremely short time we’ve been observing, therefore it never happens” nonsense.
What magic barriers makes it impossible for microevolutionary changes to accumulate over time into macroevolutionary ones?
Please try an honest answer this time, thanks.
LoL.
One species giving birth to another species. Who would have cause to doubt it. Just check out all the YouTube videos.
This is not so.
Easily a common design concept would explain all likeness in biology.
Its more likely.
Your saying everyone having eyeballs demands common descent from a original eyebally critter.
Yet a creatore with the eyeball idea would give it to all critters on creation week.
why not?
so with this option it nullify’s common descent claim for evidence based on eyeball likeness oR the DNA behind it.
Morphology/genetics are hand in glove and both are accounted for by common design.
Where is the evidence for common descent aside from rejecting any other option??
Its all just looking at biology likeness and guessing as to why?
Thats not scientific evidence for common descent.
There is none but mere lines of reasoning.
Been away for a bit, I see Mung is still the shameless liar he’s always been. Allan Miller was actually commenting on the fact species come from ancestral species, which they do, and species leave descendant species, which they do.
the alternative hypothesis is the classic one.
Separate creation.
Your saying its impossible a creator would make apes/men look so alike and so its not an option.
Why wouldn’t he? What else would he do to make a human with the best body for fun and profit.
There is no evidence in ape/human likeness for common descent. its only a line of reasoning where other option(s) have been rejected.
then your side convinces itself that the likeness is proof for common descent.
nope. just a conclusion based on looks.
Biology likeness not only fits a common DESIGN concept it could only be that way from a creator.
all these nests fit in a common design equation.
Yet its not just anothyer option. it nullify’s common descent as being based on scientific investigation of morphology/genetics. both are just lines of reasoning where other options are first rejected.
So no science is going on.
As usual.
Does anyone take Byers seriously enough to respond to him? Don’t think I do.
I have occasionally (but rarely) replied, mostly as a courtesy to a guest.
Mung,
Still wrong Mung. You claim to accept common ancestry yet think that it is merely metaphorical. You might want to revise one of those positions.
Evolutionary informatics: Two and a Half Engineers analyzing models of evolution under the false assumption that modelers engineer them to generate solutions to problems.
Well then my comment either was well done, which it was, or not well done in either case the evolution side fails to take me on.
Why not use this one time to show mE why my idea was not serious or right??
Why shouldn’t I think you simply are unable to easily, or at all, handle it.
Show me why my idea is so dismissable??
why make a post to say its dismissable but not include the reasons why?
its suspect your just irritated.
I protest its not a serious answer to a serious YEC poster and a serious ly well done comment.
AGAIN why wouldn’t a creator bring a common design to biology???
In excluding this option you can’t say common descent is the only hypothesis and so thats its proof for it being true.
Its illogical and i don’t say that much when I post.
Evolutionism is all comparisonism in morphology and genetics.
Sure it is. right or wrong but thats the thinking.
so another answr for comp[arisonism NULLIFY’s common descent being right just based on observing likeness in biology.
Seriously where am I wrong in my analysis??
But I don’t share your confusion. A species is an abstraction. A species neither gives birth nor is a species birthed. Biologists really ought to be forced to take courses in philosophy lest they make fools of themselves.
If Erik’s trying to make a point that’s probably it.
I first became aware of Robert Byers back in 2008 on the old RichardDawkins.net forums. Since that time, I think I have responded to him a total of four times. With single-sentence posts.
Mung,
So what’s your excuse then?
Mung,
Perhaps, as I have suspected all along, we are talking of different species concepts. You have quibbled at my usage as if I was adhering to yours. There are some 20-odd different species concepts. A noted philosopher of biology such as yourself would presumably be aware of this.
A species – a collection of individuals among which gene flow can occur – most certainly does have both ancestors and descendants. That was the sense in which I used the term. It’s not an abstraction, it’s an actual thing, the set of individuals that can be genetically linked to other such collections of individuals even if not currently capable of gene flow. It’s not something in the mind of Plato – at least, not in the sense I intended when I wrote the words about which you now endlessly carp.
Do you think there is NO sense of the word ‘species’ in which two species can share common ancestry? Or for that matter Family, Order, etc? How about tribes? Languages? ‘People’? I mean, that’s just an abstraction, right?
Allan Miller isn’t saying that species give literal birth to new species, as if they were a singular biological entity that could become pregnant. What he’s saying is that it is literally true, that species have ancestors and descendants. He’s not saying that the process by which those descendant species come about, is directly identical to the process of animal birth. You’re focused on the idea of birth, rather than the idea of ancestors and descendants. This is what leads to your confusion. And it’s yours, not biologists in general or Allan Miller’s in particular.
Surely it can’t be the lack of a directly equivalent generational thing that’s the issue? If that were the case, only parents and immediate offspring could be said to be related, sans scare quotes, which I doubt Mung would agree with. I think it might be more the spectre of essentialism. Even those who accept common descent seem to think in terms of essence, which is a bit of a conundrum to me.
Common and Spotted Sandpipers. The actual things. Genealogically related or not?
That’s not quite right. At least it’s ambiguous and contentious.
Though a species is not exactly like an individual organism, it doesn’t follow that we can’t use “ancestor” and “descendant” in an analogous way. Analogies are perfectly kosher in science as long as there’s no ambiguity about the points at which the analogy breaks down.
I think it’s problematic to say that species are abstractions. Michael Ghiselin (in The Triumph of the Darwinian Method argues that species should be understood as concrete spatio-temporal individuals that are composed of parts, just like sports teams and committees.
When Mayr stresses the importance of Darwin’s anti-essentialism, he is almost right. In taking species as populations, we can understand Darwin as revising the metaphysics of biology: species are particulars, not generals.
The argument of Origin can be compressed into: the patterns and processes that are observed across multiple lines of evidence (biogeography, embryology, paleontology) are puzzling if species are generals, but make perfect sense if species are particulars. That’s in contrast with the entire metaphysical tradition that treated species as the lowest level of generals (as we see in Linnaean classification).
I do think that more biologists should read philosophy of biology. If they did they would make fewer blunders when arguing with creationists.
No fair, Allan. That’s my question. I asked about the White-Crowned Sparrow, the Golden-Crowned Sparrow, and the White-Throated Sparrow.
The ID advocates and creationists here, even those who say they accept the reality of common descent, get awfully vague when asked whether they accept that these species had a common ancestor. We hear a lot of well-I-dunno-about-that and well-let’s-talk-about-this-other-issue.
Kantian Naturalist,
You’re actually agreeing with Mung. He argues (in pursuit of a rather weak point) that I used a metaphor by saying ‘related’, having previously chastised Erik for getting carried away by analogy – as if, having got fed up with a particular instance of over-extension of an analogy, I am ever shackled in the deserts of linguistic tyranny, barred from using (even mixed) metaphors ever again.
But: species really are related (at least some, if UCD is not the case; all if it is). Common ancestry really does mean common ancestry. We are individually mosaics of our ancestors. But, so are species. Mosaics of real, not metaphorical, ancestors. Individuals don’t have a different kind of ancestor from collections of individuals, which is all a species is at a moment in time.
Ha! It’s fine when Creationists (or philosophers!) make blunders on biology, then! Just pick on the biologists. 🙂 No amount of reading on my part will address Mung’s unfamiliarity with the range of species concepts. I need to imagine a Mung on my shoulder as I write. All biological terms will be viewed through the lens of Merriam Webster.
Joe Felsenstein,
I must acknowledge your priority within this thread. I have prior publications (ie blog comments) using the Sandpipers dating all the way back to 2013 though.
In origin issues we are way beyond this long ago.
Creationists, YEC or anyone, gladly accept “species” being from a original kind. Just like with people. We need this to put a ceiling on KINDS that were on the ark or made on creation week.
All YEC say all bears come from a original bear kind. i go farther and say bears, wolves, probably seals, marsupial bears/wolves, etc etc are from a original KIND off the ark. Just one kind. Then changes in the body plans.
We do not desire separate created sparrows.
yet these sparrows may not be a result of common descent but like people totally”evolved” into their colours/looks etc unrelated to other people.
Likeness is the only evidence for common descent, morphology/genetics, that evolutionists have.
yet it only works as EVIDENCE if there are no other options.
if there are other options there is not just other options. iT nulllify’s the evidence for common descent even if common descent was the truth.
Its all just lines of reasoning empty of biological scientific evidence.
SO THIS lack of bio sci evidence is the reason there is, and will in time be agreed, that the false ideas of evolutionary biology have persisted into the 21 century.
It’s been known to happen.
No, your mistake was to speak of species as having ancestors and descendants and then to deny that such language is metaphorical, while at the same time complaining about people who use analogical language in biology.
cake. eat. 2.
The problem was wasn’t in saying ‘related’.
My specialty!
🙂
The population of walruses 10,000 years ago was ancestral to the population of walruses today.
I don’t see any imprecision in saying that. If Mung is unhappy at us calling it fairly precise, and wants to argue that it is instead “metaphorical”, fine, Mung is free to. But that does not establish that biologists are muddled on this point.
Mung,
1) It isn’t metaphorical. It wouldn’t matter if it was, because see 2, but it isn’t. (One might quibble about the implication that a population is an individual, but you can hardly think that that’s what I think. If it’s just about singular vs plural, stick an s on the end, although it’s usually less ambiguous if you don’t).
2) Even if it was, there is no inconsistency between my carping at bad or over-extended analogies with any usage of analogy or metaphor on my part. The difference is: my analogies and metaphors are good. 🙂 The idea that criticism of a particular piece of rhetoric disbars one from all rhetoric belonging to that general class is clearly not sustainable. It’s not that analogies are bad, it’s getting carried away with them.
That was precisely the word you picked up! You demanded to know why I’d scare-quoted it. It was not my use of the singular ‘ancestor’ or ‘descendant’ that got you on my case, but the word ‘related’, complete with scare-quotes.
I realise this is boring for everyone else, but there is an interesting issue here, related to collections, their relationships, and the way Creationists seem to view them.
Here’s a simple breakdown:
‘A couple’. Is it metaphorical or literal to say that a couple can have both ancestors and descendants? Me, I’d go with literal.
OK, suppose now that a species has been reduced to just two members. Is it metaphorical now?
Now, how about 3? 4? 10,000? As you add members, at what point does it become metaphorical?
One might protest that ancestors and descendants must be individuals, and populations aren’t individuals. But they are collections of individuals, while even ‘true’ individuals have collections of ancestors and descendants in sexual species. And, indeed, the boundaries of an individual are often fuzzier than we might like. What’s the individual in a beehive? Or a fairy ring? Or sperm?
A population can be viewed simply as a subdivided gene pool. An individual is a subdivision of that pool (as, for that matter, is a gamete). It would be nonsensical to suggest that the copying of that pool through time is not ‘true’ descent, as if the term is reserved for single individuals, when it is only via those individuals that it happens at all.
Pearls before swine.
Or give up those ridiculous stories and deal with reality.
It is reality. its witnessed. how do you know its not true? Were you there?
Anyways we do need ceilings and its just strange error for evolutionists to say creationists don’t think body plans in biology don’t change.
We do but mechanism is the issue.
peoples looks are case in point.
Robert Byers,
I thought that line was just a myth. But no, a real sighting.
Allan:
Oh, no. Here’s scumbag Ken Ham using it to indoctrinate children:
“Missionary lizards” my ass.
How many generations have elapsed from for example shark fossils to current sharks? What was the evolution meanwhile?
I was obviously not talking about short time. I was asking if anyone can, over any time, point out a process of evolution from one specific species to another. Any species of your choice. No answer.
And the signal in this case was “e”, right?
If the phylogenetic signal can be lost (and evidently is), what justifies the theory of a single phylogenetic tree for all life (in genetic terms)?
Erik,
The places where it is not lost. There’s this all-or-nothing flavour to criticism of this data – a version of false dichotomy. Imagine a true evolutionary process where a particular position has been through 10 changes and is back where it started, with no extant descendants of the intermediate states. The phylogenetic signal at that position has been lost. There are other positions.
Okay, let’s imagine a particular position that has been through 10 changes and is back where it started, with no extant descendants of the intermediate states.
If it’s back where it started, how do you know it went through 10 changes? What distinguishes it from a continuous phylogenetic signal found at some different position?
Erik,
Some things you don’t know. And some things you do. Just because you can’t know everything does not mean you know nothing.
Sure. So, that said, what do we know?
This makes the same point as the OP. Except that Darwin’s debate becomes one not just against creationists, but also against metaphysicists, which is the more specific aim of the OP.
Erik,
You don’t. Because the phylogenetic signal has been lost.
Nothing. What is important is the collective evidence, precisely because real evolutionary processes inevitably erase the signal, position by position, if intermediates are not preserved. The Creationist points to a possibility of anomaly and concludes that the entirety must be anomaly, over-extension when there are reliable and testable*** means to tell which is signal and which is noise.
And, as I say, it is the ‘noise’ which is the clearest signal. Without differences, there is no phylogenetic signal either, other than likely collective common descent with no order.
It’s both. The differences embed in a sea of similarity. Both are informative.
*** One can test one’s methods on artificial datasets – those that genuinely derive from an evolutionary process, albeit one taking place in a computer. If they get close to the ‘true’ phylogeny that you have separately recorded, that cuts through much of the ‘what about THIS anomaly?’ cheese-paring.
Erik,
Read this comment::
I thought so.
I thought that too.
So there is no specific data for common descent and the analogy with linguistics is complete again. In linguistics also there are genetic signals and there’s their loss and the evidence stops at some point. The collective evidence is compatible with the broad assumption either for or against common descent, which means the assumption either way is rather a philosophical or ideological position, not scientific. In scientific terms, at best an unconfirmed hypothesis.
Why common descent? If you say it’s a scientific position, then try a scientific answer.
@keiths
“…the relationships given in Figure 1, as determined from morphological characters, are completely congruent with the relationships determined independently from cytochrome c molecular studies…”
The keyword here is “congruent”.
By analogy with linguistics, the fact that all languages are made of vowels and consonants that occur in pronounceable sequences and are arranged into words and sentences, is COMPLETELY CONGRUENT with the hypothesis of common descent and sure as hell points towards it, but it’s not enough.
Let’s grant everything you are quoting. Are you saying that “congruent” is sufficient proof for common descent? If there is more “collective evidence” to make the case sufficient, then why not present it? I must conclude that “congruent” is the best you have, but “congruent” works both ways.
Erik,
The analogy should not be over extended. There are things which are similar and things which are different. If you have genes thousands of residues long, you cannot sensibly compare this to the limited utterances of the human voice box and the significantly different mode of transmission and mixing in terms of the signal available for analysis.
Pure bullshit. You subject the dataset to an objective test to see if the data supports a tree phylogeny, then see if other gene trees support or reject the hypothesis – do science, in other words – and you STILL say it’s ‘ideological’. That’s profoundly ignorant.
What is unscientific about the extensive statistical analysis of phylogenetic data? It may comfort you to curl up in a ball and repeat the mantra ‘it’s unscientific I tells ya’. In which case, go in peace with your impenetrably woolly understanding.
When the evidence is compatible with either conclusion, then to draw just one conclusion is ideological, not scientific. To say it’s scientific is ignorant bullshit.
What is scientific about looking at the data and making a conclusion when the data is insufficient for it?
Erik,
Hahaha! You are a card. A positive paternity result is compatible with either conclusion – my client is, or isn’t, the father. Will you be informing the courts of the weight of your learned scientific opinion?
So what’s insufficient about the data on common descent of Spotted and Common Sandpipers?