Biological Evolution (part 1 of ?)

Beginning a more in depth inquiry into the nature, scope, and controversy surrounding evolutionary theory as applied to biological systems.

This is an introduction, but I hope to follow soon with more in depth analysis of the extent to which Darwin's theory of natural selection can account for all of the variation and complexity of the biological world. Darwin himself said that natural selection "was the main but not exclusive means of modification" (Origin of Species, p. 6). I hope to show that natural selection, while certainly operative in evolution, is by no means the main or single contributing factor in speciation and biological complexity.

Category:

Science & Technology

Tags:

• darwin
• evolution
• complexity
• science
• dennett
• margulis
• goodwin
• kauffman
• lewontin
• lovelock
• mayr
• natural
• selection

[moneycrab]

remember that while punctuated equilibrium can put pressure on the rate of especiation by destabilizing the relative benefit of genetic variation, it does nothing to the underlying rate of genetic change which is brought about through arbitrary copy errors, radiation, chemicals, etc....

[0ThouArtThat0]

are you familiar with the research showing that E. Coli responds to a nutrient poor environment by increasing the rate at which mutations take place, such that new genes that would allow for production of enzymes capable of metabolizing surrounding chemicals are more likely to arise? This shows that there is more than just error involved in mutation. Organisms, even at the bacterial level, are capable of inducing mutation when need be.

[moneycrab]

Did this study indicate that the organism itself began increasing the mutations? Perhaps a nutrient poor environment is just more conducive to mutation.

Because what you are saying is that there are observed processes by which E.Coli begins to arbitrarily alter its own genome.

[0ThouArtThat0]

The study (Cairns et al, 1988) does indeed challenge the central dogma (DNA--->mRNA--->protein) by suggesting something similar to evolution via Lamarckian acquired characteristic is possible. It is controversial, of course. But nonetheless, it shows we have much to learn about the complexities of evolution. I tend to lean more toward the developmental systems paradigm than the neo-Darwinist, which seems to have prematurely defined evolution based on NS alone when other processes may be at work.

[pungentprincess]

Love the video. I have heard of increasing genetic diversity from phagocytosis, but I didn't ever think it could be a driving 'force' more than natural selection.

The idea that An organism creates the environment as much as the organism, I think (though I'm not sure) that this is widely accepted. When someone describes an environment as shaping an organism, it's more a simplification of the whole process rather than a disregarding the fact that organisms contribute to their environment.

[0ThouArtThat0]

Have you looked into the recent work in epigenetics, or into Developmental Systems Theory? These fields are providing a lot of evidence to suggest that evolution involves more than differential gene selection, and that reducing it to that isa vast oversimplification

I think it is well accepted within science generally that the study of an organism is really the study of an organism-environment field. But I run into a lot of people who learned biology from Richard Dawkins that seem to disagree.

[Ripley747]

I apologize if any of this is too soon. I haven't watched your other vids yet.

1) We know Darwin was wrong...about MANY things. That is one reason why evo bio's refer to it as evolutionary biology and NOT Neo-Darwinism.

2) Natural selection is NOT the only driving force. Darwin also proposed another called sexual selection. If you've never heard of it, look it up. It's actually interesting.

3) The symbiotic relationship you mentioned is a form of natural selection and not separate from.

[StAndAl0neCompl3x]

It's well accepted by Darwinists already that Punctuated Equilibrium is the most common mechanism of evolution. Gradual accumulation of adaptation has already been admitted as a secondary - rather, rarer - mechanism. So I'm not quite sure why you distinguish between this and "neo-Darwinism." I do know that creationists are fond of that term, so watch yourself there, ;-) Other than that, you are right that Natural Selection as a mechanism is still debated in biology circles.

[Howie47]

You don't "know" any such thing. Neither does anyone else. The overwhelming scientific evidence is that there was no single or "universal common ancestor". Life incorporates a systematic way of rearranging it's DNA to meet environmental changes (pressures). It is known and been scientifically proven, that it can happen very quickly. That's why catastrophes cause sudden changes in life. Why life before the flood were huge in comparison to after.

[aramhampson]

you "know" i speculate that speciation is part of the biologial/genetic/chemical process regardless of mutation and environmental influences. Biology when viewed with fractal algorythms will diverge and form its own path

[Ripley747]

A couple points.

1) You make it sound like natural selection says, "Hey, I need to kill some of these guys. Let's select for a predator." It's WAY more complicated and there itricate (you go on later to explain why-well, sort of).

2) If you want to be taken seriously by anyone, please stop saying "Darwinist" and start saying "Proponents of evolution" or "Evolutionary biologists."

[twinkazz]

I agree with in that people possibly think too much about gradual evolution. From what i have seen an learned at university, evolution and adaptation fall in between punctual and gradual. Small changes occur over time, until major innovations happen (such as changing from 2 tissues layers to 3, or the adaptation of a jaw, or amniotic eggs etc) and this allows a huge amount of speciation as they are able to exploit more niches in the world and so natural selection will run in more directions.

[patrickledford420]

nice name i thought it was serious at first there really are creationist that call gravity that

[patrickledford420]

@Tahnz86 no it didnt have to happen for evolution to be true and abiogenesis (im not saying its true) is simple chemicals to replicating rna than more complicated cells and evolution is a fact

[patrickledford420]

@Tahnz86 what the 0.5 percent send me the list u obviously havnt studied common sense

[patrickledford420]

@Tahnz86 there is the theory of evolution and the fact both are true we evolved from apes we are apes ID has no evidence fossil record is evidence of transition and i think u beleive in a creation myth thats y ur deniing evolution