Clade

[juvenissun]

No, those animals are rarely if ever used for medicines targeted for humans.

I guess it is highly likely people use fish to test some human drugs.

 

[PsychoSarah]

I guess it is highly likely people use fish to test some human drugs.

If they do, it would be only to see if it killed stuff right away. Fish would not be good test animals for human medicine, especially not for medications.

 

[Dizredux]

I guess it is highly likely people use fish to test some human drugs.

I don't I have ever heard that happening. I suspect that fish and humans are too far apart for that. The lines did separate a very long time age.

Dizredux

 

[juvenissun]

juvenissun

You keep asking about the value of cladistics. Here is a very good article from UC Berkeley titled Why Do Biologists Need Cladistics? The Need for Cladistics

There are several articles teaching about cladistics. I hope they are some help.

Dizredux

OK, this one is interesting:

Quote:

As with any other system in science, a model is most useful when it not only describes what has been observed, but when it predicts that which has not yet been observed. Cladistics produces hypotheses about the relationships of organisms in a way that, unlike other systems, predicts properties of the organisms. This can be especially important in cases when particular genes or biological compounds are being sought. Such genes and compounds are being sought all the time by companies interested in improving crop yield or disease resistance, and in the search for medicines. Only an hypothesis based on evolutionary theory, such as cladistic hypotheses, can be used for these endeavors.

End quote.

I am not convinced that we need the idea of common ancestor to do prediction. Basically ANY classification system can do some predictions. That is a basic principle of science.

It suggested that cladistics is "better". Well, that IS the question in the OP. I like to see an example which demonstrates that it is indeed better.

If I don't see an example by now, I don't think I would ever see one in this forum.

 

[juvenissun]

I don't I have ever heard that happening. I suspect that fish and humans are too far apart for that. The lines did separate a very long time age.

Dizredux

Google this: "use fish to test drug".

 

[PsychoSarah]

Google this: "use fish to test drug".

You google it

 

[Dizredux]

Google this: "use fish to test drug".

I did and did not see much so could you point out one in particular that you think is relevant.

Dizredux

 

[Dizredux]

OK, this one is interesting:

As with any other system in science, a model is most useful when it not only describes what has been observed, but when it predicts that which has not yet been observed. Cladistics produces hypotheses about the relationships of organisms in a way that, unlike other systems, predicts properties of the organisms. This can be especially important in cases when particular genes or biological compounds are being sought. Such genes and compounds are being sought all the time by companies interested in improving crop yield or disease resistance, and in the search for medicines. Only an hypothesis based on evolutionary theory, such as cladistic hypotheses, can be used for these endeavors.

This makes perfectly good sense to me. Do you see any problems with it?

Dizredux

 

[sfs]

What strawman is this? I didn't say anything had to be 100% flawless.

The claim was made that cladists have some ability to objectively distinguish "general similarity" from "similarity due to common ancestry".

They don't.

It is based on subjective rationalization.

What's subjective about the presence or absence of a specific ERV or SINE at a specific place in the genome?

 

[juvenissun]

What's subjective about the presence or absence of a specific ERV or SINE at a specific place in the genome?

SFS, since you visited here, what do you think about the question in my OP?

 

[PsychoSarah]

I thought the cladistics bears the idea of common ancestry. Does it?
If not, then which one does?

Does it matter? Ultimately the OP is asking how useful clades are, not necessarily what they are.

 

[Loudmouth]

I thought the cladistics bears the idea of common ancestry. Does it?
If not, then which one does?

Since cladistics bears the idea of common ancestry, why are you asking about Linnaean taxonomy?

 

[Loudmouth]

I am not convinced that we need the idea of common ancestor to do prediction. Basically ANY classification system can do some predictions. That is a basic principle of science.

Then show us those predictions, and how they are falsifiable and accurate.

 

[Loudmouth]

SFS, since you visited here, what do you think about the question in my OP?

What do you think of sfs' question?

 

[sfs]

SFS, since you visited here, what do you think about the question in my OP?

Phylogenies -- which is what cladistics is designed to determine -- are certainly of practical use for me. I use the genomes of closely related species to determine which alleles are ancestral and which are derived, for identifying cases of positive selection (among other uses); without knowing which species to compare, I would have no basis for extracting the information. We use phylogenies to determine which species to sequence so as to get the most bang for our sequencing bucks. We use them to determine which parts of the genome are functional, since they're the parts that are conserved across species. In particular, we need them to determine which parts are functional only within a particular lineage.

More broadly, without the framework of common descent and an implied phylogenetic tree, comparative genomics would have no coherence, and we'd have no structure for thinking about our data. I have no idea how we'd function without it.

 

[juvenissun]

Phylogenies -- which is what cladistics is designed to determine -- are certainly of practical use for me. I use the genomes of closely related species to determine which alleles are ancestral and which are derived, for identifying cases of positive selection (among other uses); without knowing which species to compare, I would have no basis for extracting the information. We use phylogenies to determine which species to sequence so as to get the most bang for our sequencing bucks. We use them to determine which parts of the genome are functional, since they're the parts that are conserved across species. In particular, we need them to determine which parts are functional only within a particular lineage.

More broadly, without the framework of common descent and an implied phylogenetic tree, comparative genomics would have no coherence, and we'd have no structure for thinking about our data. I have no idea how we'd function without it.

Fine. I think you are talk about studies in genetics.

Is that true that all you said are studies that can be done in a number of years? Within this period of time, you can "trace" the generations back and forth and compare one from another horizontally and vertically.

If it is true, then I think the idea of common ancestry for you and in genetics should be strictly separated from that used in paleontology (even in anthropology). Basically this is the same problem as the one we have seen in the definition of "evolution".

In your study (genetics), do you ever use the clade as deep back as "family" or "order"? Or are you mostly play at the level of species or genus?

 

[juvenissun]

Since cladistics bears the idea of common ancestry, why are you asking about Linnaean taxonomy?

I thought it is one which does not.

 

[juvenissun]

Does it matter? Ultimately the OP is asking how useful clades are, not necessarily what they are.

Not at all. I know the cladistics IS useful. But the idea of common ancestry embedded in cladictics may be not.

 

[sfs]

Fine. I think you are talk about studies in genetics.

Is that true that all you said are studies that can be done in a number of years? Within this period of time, you can "trace" the generations back and forth and compare one from another horizontally and vertically.

If it is true, then I think the idea of common ancestry for you and in genetics should be strictly separated from that used in paleontology (even in anthropology). Basically this is the same problem as the one we have seen in the definition of "evolution".

In your study (genetics), do you ever use the clade as deep back as "family" or "order"? Or are you mostly play at the level of species or genus?

We use everything from human/chimp to "all mammals". Others probably have uses that extend even farther. Sorry, but your distinction doesn't work.

 

[juvenissun]

We use everything from human/chimp to "all mammals". Others probably have uses that extend even farther. Sorry, but your distinction doesn't work.

OK, if you said so.

Disappointing.