Usefulness of the theory of evolution

[CharonY]

Of course biology has models or predictive power. In many cases they tend to be more qualitative in nature, however. You may want to look up how e.g. genome annotations are conducted, just to get an idea on this topic.

[too-open-minded]

Thats freaking awesome! I'll look it up but I would very much appreciate any links or sources you could site me to.

 

So you could look at genomes and be able to tell how a species is evolving and have a good idea of what their adaptations will be like in the near future?

[CharonY]

Not like that. There are too many uncertainties (i.e. environmental factors) that would be impossible to predict population-wide changes. The only possibility would be under highly controlled conditions (the Lenski experiment would be an example).

I was given the example of function prediction based on the protein sequence. I think the basics should be covered in quite some textbooks. Check this out, for example http://www.ncbi.nlm.nih.gov/books/NBK21086/.

Without evolution as a basis the whole approach would be non-sensical.

[Delta1212]

I would always favour having my car fixed by a mechanic rather than a physicist. I'd be patronisingly sympathetic to anyone who thought otherwise.

By physicist, I mean someone with an advanced education in physics. The choice isn't between a guy in a lab coat with a chalkboard and a guy working as a mechanic.

 

It's between a guy who learned to fix cars working out of his garage and a guy with a mechanical engineering degree. I realize, and should have taken into account so my mistake, that when someone says physicist, people automatically assume it gets preceded by something like "experimental" or "theoretical" but for all practical purposes, an engineer is just a type of physicist. That's how they knew how to design the car in the first place.

 

I feel you may still be missing the point. Let us say, we want to sequence an organism. First of all, we would assume that DNA is the carrier of genetic information. Why? Because evolution.

Then, if we sequence it, we use methods that differentiate the four bases. Why? Because evolution.

The way we then detect open reading frames, deduce protein coding sequences, identify the amino acid sequence thereof and predict functions are all possible under the theoretical framework of evolutionary theories. Without them the approach would have to be radically different. It is therefore not only selector of bullshit (which it sometimes is, but probably not that often in a scientific context) but it is really the foundation of many actual approaches.

I may not have been clear in the point I was trying to make. I was attempting to clarify why the umbrella of evolutionary theory is useful above and beyond the fields that are heavily reliant upon it for a theoretical base.

 

You don't need to understand evolution to discover DNA or figure out what it does and how it works. Studying it will, of course, be a hell of a lot harder without that foundation, but that was my point.

 

I realize that, as has been said, nothing in biology makes sense except in light of evolution, but you don't need something to make sense to use it. Considering how the conversation had been going previously, I was attempting to explain how evolution would be useful even if we somehow had managed to achieve all of our current knowledge of biology other than evolution (and no, I don't know how we would have managed that).

 

What I was trying to say was that without the theory of evolution to act as that foundation of all of our knowledge of biology, advancing that knowledge becomes next to impossible. Evolution frames our knowledge of biology and makes it easier for us to figure out how things work. Obviously, all of that knowledge can then be attributed to knowledge of evolutionary theory, but I was shooting for a good reason why evolution all by itself is useful knowledge rather than "only" being a foundation for useful knowledge.

[akh]

Well yeah the definition of evolution is the change in allele frequency of a species over time. Although labels can narrow peoples vision and be misleading. Things aren't always as they seem.

 

 

 

Fixed

Edited August 9, 2012 by akh

[Ophiolite]

By physicist, I mean someone with an advanced education in physics. The choice isn't between a guy in a lab coat with a chalkboard and a guy working as a mechanic.

 

It's between a guy who learned to fix cars working out of his garage and a guy with a mechanical engineering degree. I realize, and should have taken into account so my mistake, that when someone says physicist, people automatically assume it gets preceded by something like "experimental" or "theoretical" but for all practical purposes, an engineer is just a type of physicist. That's how they knew how to design the car in the first place.

Engineers are not physicists. Engineers think differently from scientists. And unless the engineer designing the car also had a bunch of hands on experience fixing them then I'd pick the mechanic every time. And if the engineer did have that practical time then I'd be picking him because he was also a mechanic.

[studiot]

While many things do indeed change over time and this change is sometimes characterised as a form of evolution, in most contexts evolution refers specifically to some form of biological evolution, involving heritable characteristics mutation, natural selection, adaptation, etc. In this sense then, evolution does not apply to everything and it may be misleading to say that it does.

 

This is both wrong and right, but really useful to point out the wider meaning of the word evolution.

 

So for instance in sailing the term is used in the sense of 'An ordered development, perhaps to a conclusion'

 

This this is the exact opposite from Darwinian evolution which unfortunately is so often misrepresented as implying some purpose or advantage behind the changes, which in the case of Darwinianism are truly random.

Edited August 20, 2012 by studiot

[Arete]

How is the concept of species reliant on evolutionary biology? I know that an animal's species is defined by the boundary to producing viable offspring, but I don't know how the species of a bacteria is determined.

 

A species is generally defined as a metapopulation of organisms sharing an evolutionary history. http://sysbio.oxford.../56/6/879.short

Plenty of different species can hybridize to produce viable offspring. e.g. http://onlinelibrary...12.05571.x/full http://onlinelibrary...12.05571.x/full http://onlinelibrary...09.04471.x/full

 

This is along the same lines as antibiotic resistance. I think these all might be examples of antibiotic resistance, but I don't know the precise definitions and categorizations. I conceded antibiotic resistance in the OP (opening post).

 

A vaccine or a chemotherapeutic treatment will be also affected by evolution in the host, pathogen or vector - if the host, pathogen or vector have different evolutionary populations, they may respond divergently to treatment. Partially effective treatments may lead to selective sweeps and rapid inffectivity of the treatment. A treatment for an autoimmune disease may only be partially effective if, for instance the causes of the disease have independent evolutionary pathways. None of these have anything to do with antibiotic resistance.

 

I see the value of HWE to ecology. HWE relies on the same ideas that form the basis of evolution, but I'm assuming that an understanding of evolutionary history is probably more useful when one is trying to think of explanations for certain shifts in allele prevalence.

 

Changes in allele prevalence between populations and over time are what evolution is.

 

I always thought evolutionary distance was closely correlated with genetic variance because I've heard of people actually using DNA samples to estimate when the blood-lines of different species had split apart. From there, I assumed that we only needed genetics and not evolution because genetics gave more accurate information than evolution without ever getting evolution involved.

 

I'm not sure I understand. Genetics, particularly population genetics and phylogenetics, which I study, are subfields of evolutionary biology. Our lab is a genetics/genomics lab in the evolutionary biology department. The study of genetics and evolution, particularly at the level of the population or species, are intimately intertwined. Much of the theory which allows us to explain genetics is evolutionary theory. You can't have one without the other, at least in terms of modern science.

 

That is another example involving microorganisms.

 

Well, no, because the evolutionary history and processes of human populations will profoundly affect the dynamics of H1N1 epidemiology. If you don't understand the evolutionary dynamics of the host population, it is impossible to determine the dynamics of disease within that population.

 

Are you saying the end (and therefore the means) is different in species conservation versus the sustainment of harvesting?

 

Well, one is focused on maintaining or maximising the genetic diversity of population for the purposes of maintaining the population in a natural state in perpetuity. The other is focused on maintaining a harvest without inducing a population crash. While some of the population parameters you would want to know about each population would be the same and thus many of the techniques would be similar, they are ultimately two distinct examples of how evolutionary theory is useful.

 

Hopefully we've collectively demonstrated how it is and I hope you continue to find the field interesting