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Author Topic:   Definition of Species
Wounded King
Member (Idle past 2234 days)
Posts: 4149
From: Edinburgh, Scotland
Joined: 04-09-2003


Message 70 of 450 (542270)
01-08-2010 2:51 PM
Reply to: Message 69 by RAZD
01-07-2010 9:30 PM


Misrepresenting evo-devo
This is the area covered by evolutionary development - evo-devo - a fairly new field, where changes in hormones or environmental chemicals can affect the way organisms develop from fetus to adult.

This is a tiny proportion of what evo-devo covers. In fact something like the action/effects of Thalidomide is simply a developmental question, evolution doesn't come into it, except to the extent that perturbing normal development helps us understand the underlying developmental networks which are the principle substrate for the generation of heritable morphological variation.

You seem to be ignoring the whole developmental genetics aspect which is arguably the core of evo-devo. To make out that evo-devo is somehow removed from consideration of the genotype is very misleading.

TTFN,

WK


This message is a reply to:
 Message 69 by RAZD, posted 01-07-2010 9:30 PM RAZD has acknowledged this reply

    
Wounded King
Member (Idle past 2234 days)
Posts: 4149
From: Edinburgh, Scotland
Joined: 04-09-2003


Message 74 of 450 (543994)
01-22-2010 4:42 PM
Reply to: Message 72 by herebedragons
01-22-2010 11:15 AM


Re: Speciation discussion, expectations and reality
Why do genes mutate? Are they random or driven by environmental forces?

The answer to this is 'both', the mutation rate and indeed the differential rates of different types of mutations can be heavily influenced by environmental factors.

However these factors do not target mutations to any particular gene or locus, which is why the mutations are random.

TTFN,

WK


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 Message 72 by herebedragons, posted 01-22-2010 11:15 AM herebedragons has not yet responded

    
Wounded King
Member (Idle past 2234 days)
Posts: 4149
From: Edinburgh, Scotland
Joined: 04-09-2003


Message 82 of 450 (546329)
02-10-2010 4:10 AM
Reply to: Message 81 by RAZD
02-09-2010 10:17 PM


Re: mutations, possibilities and opportunity
I think it is usually a pretty safe bet that any IDist/creationist when they talk about species is talking about morphospecies rather than anything resembling the biological species concept of a species.

Admittedly Kaichos man seems to be making a break with tradition, I look forward to his arguing that even if a dog did give birth to a cat there is no reason not to think this is just a rare but natural part of the ecotypic morphocline.

TTFN,

WK


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 Message 81 by RAZD, posted 02-09-2010 10:17 PM RAZD has acknowledged this reply

    
Wounded King
Member (Idle past 2234 days)
Posts: 4149
From: Edinburgh, Scotland
Joined: 04-09-2003


Message 110 of 450 (570372)
07-27-2010 9:08 AM
Reply to: Message 108 by Big_Al35
07-27-2010 8:54 AM


Not even tangential to the original direction.
But clearly the red colobus monkey failed to adapt to the modern world. Its cousins, the fish, however have continued to thrive and demonstrated that they don't need this relics attributes or features. Surely, this is evolution in action. Survival of the fittest!

You seem to be becoming a master of the non sequitur, What you have written here is in fact entirely correct, but has absolutely no connection to Huntard's point that the red colobus monkey was not an ancestor of modern fish just because it became extinct while modern fish survive. So the use of the word 'but' at the start of your post is confusing.

Of course you ignore the fact that many species of fish have also become extinct, clearly showing their evolutionary inferiority to all extant species of monkey,but then it wouldn't be cherry picking if you actually tried to accurately evaluate the evidence I guess.

TTFN,

WK


This message is a reply to:
 Message 108 by Big_Al35, posted 07-27-2010 8:54 AM Big_Al35 has responded

Replies to this message:
 Message 113 by Big_Al35, posted 07-27-2010 9:52 AM Wounded King has responded

    
Wounded King
Member (Idle past 2234 days)
Posts: 4149
From: Edinburgh, Scotland
Joined: 04-09-2003


Message 118 of 450 (570408)
07-27-2010 10:16 AM
Reply to: Message 113 by Big_Al35
07-27-2010 9:52 AM


Re: Not even tangential to the original direction.
You use extinct fish to conclude that they evolved into monkeys.

You seem confused. As Jar points out the key fact isn't that the fish are extinct, the key facts are when fish start to appear in the fossil record and their morphological features.

It isn't that the fish are extinct that means they are ancestral, it is their morphology and what we know of stratigraphy. Even if there was still an extant morphospecies identical to the putative latest common ancestor of fish and monkeys it wouldn't change the conclusions.

TTFN,

WK


This message is a reply to:
 Message 113 by Big_Al35, posted 07-27-2010 9:52 AM Big_Al35 has responded

Replies to this message:
 Message 120 by Big_Al35, posted 07-27-2010 10:48 AM Wounded King has responded

    
Wounded King
Member (Idle past 2234 days)
Posts: 4149
From: Edinburgh, Scotland
Joined: 04-09-2003


Message 122 of 450 (570426)
07-27-2010 11:30 AM
Reply to: Message 120 by Big_Al35
07-27-2010 10:48 AM


Re: Not even tangential to the original direction.
Can't we track this down? DNA evidence should do the trick.

Probably not hence my use of the term 'morphospecies', which is a species classification base solely on morphology. Even if we could identify a fossil as a definitive latest common ancestor and find an identical extant morphospecies there would no way we could know how much genetic distance separated the two. That isn't to say that such a species wouldn't be interesting in terms of comparative developmental genetics, just that we wouldn't be able to have any confidence that its genome was the same as that of the LCA of monkeys and modern fish.

As an example the Burgess Shale fossil Pikaia is often suggested as an example of the sort of primitive chordate that modern vertebrates may have descended from, this doesn't mean that anyone is claiming that the morphologically similar currently extant Lancelet is the latest common ancestor of all vertebrates.

TTFN,

WK


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Wounded King
Member (Idle past 2234 days)
Posts: 4149
From: Edinburgh, Scotland
Joined: 04-09-2003


Message 184 of 450 (572485)
08-06-2010 6:27 AM
Reply to: Message 177 by Big_Al35
08-06-2010 5:20 AM


Re: Species Definition vs what matters (and why)
Lions and tigers could be classed as the same species as they can interbreed and produce fertile female offspring. They could be classed as different species as they have different behaviour, appearance and environment. The only way to clearly identify the distinctions is to investigate the DNA.

How on earth do you think DNA will do this at all? DNA won't magically turn the arbitrary definitions of species into something clear cut and well defined, it will just give us another set of criteria for a further arbitrary definition.

The idea that simply sequencing a genome will somehow reveal to you information about a species' behaviour or appearance, that you haven't already discerned by actually studying the species is ludicrous. Even in something as seemingly straight forward as coat colour there are many genes involved, there is no one gene for coat colour.

Maybe decades down the line we will have a wide enough and detailed enough library of genomic data that we could make such predictions when given a novel genome, but for most complex traits I would be doubtful if it will even be that soon.

I ceratinly don't think we will be able to take an unknown genome and from it extrapolate the morphology, behavior and other biological minutiae of the organism.

We can certainly produce high quality phylogenetic trees from the levels of families (as in mother, father and offspring) up to between the various different kingdoms of life. But this still doesn't tell us where to demarcate the boundaries for a species. In some cases it would probably be fairly straight forward, a cluster analysis based on a wide sample of commonly conserved genes would certainly separate out humans from chimps from gorilla.

The question is how we define a species when you have several much more closely related populations, in the same way that there is more of a problem with distinguishing on the basis of morpholgoy as species becomes more similar. Once again it comes down to being lumpers or splitters, what criteria do we use to define a phylogenetic species? Set the criteria too tightly and suddenly you have ten new species of tiger, for example, too loose and suddenly all of the Panthera become 1 species.

The problem here is not one of best guesses but, as has been suggested, of the fact that the whole idea of species is an arbitrary human construct imposed on the natural world.

TTFN,

WK


This message is a reply to:
 Message 177 by Big_Al35, posted 08-06-2010 5:20 AM Big_Al35 has responded

Replies to this message:
 Message 186 by Big_Al35, posted 08-06-2010 6:58 AM Wounded King has responded

    
Wounded King
Member (Idle past 2234 days)
Posts: 4149
From: Edinburgh, Scotland
Joined: 04-09-2003


Message 187 of 450 (572490)
08-06-2010 7:10 AM
Reply to: Message 180 by Big_Al35
08-06-2010 5:59 AM


Re: Species Definition
I think you are going to have to stop posting essentially bare links, especially since they rarely if ever back up your claims.

I can't find anywhere in that interview where Johanson states that Lucy represents a common ancestor for any modern species. The closest I can find is him saying 'We are beginning to look for discoveries that will shed some light on the beginnings of the lineage of Homo, which ultimately gave rise to us, Homo sapiens.' which doesn't say anything about Lucy.

The only other thing I can find is the magaziens own preamble which says, 'At the time she was found, Lucy was our oldest-known human ancestor by more than a million years. '

Which is still very far from saying Lucy is the common ancestor for any modern species.

TTFN,

WK


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Wounded King
Member (Idle past 2234 days)
Posts: 4149
From: Edinburgh, Scotland
Joined: 04-09-2003


Message 188 of 450 (572491)
08-06-2010 7:15 AM
Reply to: Message 186 by Big_Al35
08-06-2010 6:58 AM


Re: Species Definition vs what matters (and why)
This would depend on whether you believe in ID or not.

Is this another case of creationism hiding in ID's clothing? I can understand a creationist 'created kinds' approach being in line with what you say, but as far as I can tell it has nothing to do with actual Intelligent Design arguments.

And none of this addresses the fact that since god didn't leave an FAQ behind about discerning kinds through genetics, the way to do so is far from obvious if indeed such a thing exists.

TTFN,

WK


This message is a reply to:
 Message 186 by Big_Al35, posted 08-06-2010 6:58 AM Big_Al35 has responded

Replies to this message:
 Message 189 by Big_Al35, posted 08-06-2010 8:48 AM Wounded King has responded

    
Wounded King
Member (Idle past 2234 days)
Posts: 4149
From: Edinburgh, Scotland
Joined: 04-09-2003


Message 191 of 450 (572515)
08-06-2010 9:25 AM
Reply to: Message 189 by Big_Al35
08-06-2010 8:48 AM


Re: Species Definition vs what matters (and why)
And in what way is genetic barcoding not still just based around arbitrary species definitions? Simply choosing the Cytochrome Oxidase 1 as the arbiter of all species classification seems nothing but arbitray to me.

TTFN,

WK


This message is a reply to:
 Message 189 by Big_Al35, posted 08-06-2010 8:48 AM Big_Al35 has not yet responded

    
Wounded King
Member (Idle past 2234 days)
Posts: 4149
From: Edinburgh, Scotland
Joined: 04-09-2003


Message 199 of 450 (572538)
08-06-2010 11:36 AM
Reply to: Message 196 by Big_Al35
08-06-2010 11:21 AM


Re: Species Definition vs what matters (and why)
He clearly talks about the roots of our lineage and the earliest Homo found.

Yes he does, in the context of where he sees research going in the future. He absolutely says nothing about identifying a common ancestor for the various species of Homo. It is also worth noting that something being the earliest homo found in no way necessitates it being the common ancestor of all subsequent species of Homo.

TTFN,

WK


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 Message 196 by Big_Al35, posted 08-06-2010 11:21 AM Big_Al35 has not yet responded

    
Wounded King
Member (Idle past 2234 days)
Posts: 4149
From: Edinburgh, Scotland
Joined: 04-09-2003


Message 208 of 450 (573268)
08-10-2010 4:39 PM
Reply to: Message 204 by Big_Al35
08-10-2010 8:18 AM


Pushing back the boundaries of ignorance.
I love this.

I wouldn't use the word misconstrue, I would use the word disagree.
...
Again I completely disagree.

You then go on to make a load of ridiculous wrong statements about genetics which you have clearly misconstrued.

It has the same properties including things like grammar (stop codons)

No, it doesn't. You need to learn the difference between analogy and reality. Can you point me to the grammatical elements which tell me to skip ahead and miss out four paragraphs? A stop codon is not a full stop.

eg we have different fingerprints, retinas etc....this uniqueness must also be coded into the DNA with some sort of randomization mechanism (using a unique seed) built in. This in itself would require huge amounts of DNA.

Total bollocks, the randomising element doesn't need to be in the DNA, it is provided by the variable nature of the environment, the stochastic nature of the physical world.

Insisting that somehow the random elements must have been coded into DNA is just the even more absurd flip side of the argument that the non-random patterned elements of DNA must have been coded in. When in reality we have perfectly viable naturalistic mechanisms which account for both the 'information' we find in DNA and the variable nature and effects of environmental factors on development.

It serves your purpose to keep the rest of us in ignorance.

Then how kind of you to strive to maintain your ignorance at such a high level.

TTFN,

WK


This message is a reply to:
 Message 204 by Big_Al35, posted 08-10-2010 8:18 AM Big_Al35 has responded

Replies to this message:
 Message 212 by Big_Al35, posted 08-16-2010 8:28 AM Wounded King has responded

    
Wounded King
Member (Idle past 2234 days)
Posts: 4149
From: Edinburgh, Scotland
Joined: 04-09-2003


Message 211 of 450 (574486)
08-16-2010 8:09 AM
Reply to: Message 210 by Big_Al35
08-16-2010 8:00 AM


Re: Species Definition vs what matters (and why)
I think you mean to say that scientists realize that DNA offers far more answers and solutions than are currently on offer using the alternative methods.

No he doesn't mean this, once again your reading comprehension seems to have failed you.

And anyway they don't have access to DNA from fossil evidence so this discussion is moot.

Oh there we go, that would be the entire point of what RAZD is saying then, that when DNA evidence simply isn't available there are alternative methods that can be used. And when these alternative methods are used for organisms where DNA is available the phylogenies produced from the different methodolgies accord incredibly closely.

TTFN,

WK


This message is a reply to:
 Message 210 by Big_Al35, posted 08-16-2010 8:00 AM Big_Al35 has not yet responded

    
Wounded King
Member (Idle past 2234 days)
Posts: 4149
From: Edinburgh, Scotland
Joined: 04-09-2003


Message 214 of 450 (574501)
08-16-2010 9:08 AM
Reply to: Message 212 by Big_Al35
08-16-2010 8:28 AM


Re: Pushing back the boundaries of ignorance.
I am guessing you are going to tell me now that some people are born with three legs?

I'm not sure that is what I would have said, but as it happens it is indeed the case that some people are born with three legs. Huntard had an example and you can see Smillie and Murdoch (1952)(PDF) and Zhao et al. (2005) (PDF) for some further examples from the scientific literature.

It is more common for multiple limbs to be the result of incomplete twinning but actual duplications, such as in these examples, do exist.

For other examples of environmental factors that can radically affect normally stereotyped embryological development see Thalidomide, Cyclopamine, Warfarin, diethylstilbestrol and many others.

Since you could indeed predict a reasonable rejoinder to your question why didn't you just check it out for yourself? It barely took me a minute to find multiple examples of people born with three legs.

TTFN,

WK


This message is a reply to:
 Message 212 by Big_Al35, posted 08-16-2010 8:28 AM Big_Al35 has not yet responded

    
Wounded King
Member (Idle past 2234 days)
Posts: 4149
From: Edinburgh, Scotland
Joined: 04-09-2003


Message 224 of 450 (614082)
05-01-2011 2:08 PM
Reply to: Message 220 by Big_Al35
05-01-2011 12:27 PM


Re: Pushing back the boundaries of ignorance.
Given your pevious showing on this thread the answer is probably because you misunderstood what the program was clearly saying. As has been pointed out though, without any details of what the program was it is hard to say.

After all you might have just popped in a DVD of the latest canards from the Discovery Institute, in which case you may have understood what they said perfectly. Although what you describe sounds like a remarkably tangible and specific claim to have come from the DI who favour vague and incohate arguments based on intangible and unusable metrics.

TTFN,

WK


This message is a reply to:
 Message 220 by Big_Al35, posted 05-01-2011 12:27 PM Big_Al35 has responded

Replies to this message:
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