Can science explain macro-evolution?

Question

Can science explain macro-evolution?

Answer 1

Science can explain macro-evolution, yes.



The terms "micro-evolution" and "macro-evolution" are not much-used by scientists, and certainly not in the way that creationists use them.

To a scientist, Micro-evolution is evolution within a species or population, over a short timescale (a few generations); Macro-evolution is evolution over a longer timescale (a few million years).

And macro-evolution is just lots and lots of micro-evolutionary events added up.



If I step an inch a day, I'll eventually walk a mile; give me long enough and I'll circumnavigate the globe.



To use your human hair example, a mutation in the genes for hair pigmentation will change its colour; a mutation for the structural proteins of the hair will change its thickness or shape; a mutation in the patterning-genes for where follicles are laid-down will change the whole body's hair-pattern.

Feathers are structures unrelated to hair, BTW - feathers evolved from reptile "scutes" (a skin structure related to scales; the "plates" of a tortoise's shell are scutes). We know this because there is a mutation in birds which can cause feathers to be replaced by scutes on some body-portions (in fact, this is normally the case on the legs of many birds).

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Edit:



> "thanks griblin, you desribed natural selection i.e but i still have a hole in my knowledge. I may be mistaken but natural selection and evolution are not the same."



You are correct - Natural Selection *causes* Evolution.



> "For example natural selection will work with evolution but not generate or design biological traits."



"Design" is a loaded word, implying external, intelligent input - which is inappropriate in science.

But you are correct, Selection does not generate Variation in a population (in fact, selection *reduces* variation, by "weeding-out" detrimental traits).

It is *Mutation* which causes the variation upon which natural selection acts.



> "unless im wrong mutations and variations within genes are already present allowing for limited variation. This is what is bothering me."



Mutations occur at a relatively constant rate in a population (there may be certain circumstances whicyh increase the rate, but those are rarer).

So, there will always be a background level of variation in the population. And, though selection will act to decrease the variation, ongoing mutation will act to maintain the variation.

Answer 2

Yes it can.

I don't understand how some don't accept macro-evolution but they're ok with saying mircoevolution is cool. Macroevolution is microevolution over a longer period of time. I mean what do you think happened? god placed all creatures and plants on earth and then they've evolved (but not much only mirco-ly) over whatever time you believe the earth to have existed... That didn't happen and I don't know anybody who believes that.



The first life that was on this planet started off as tiny and it grew and diversified into every kind of plant, mammal and reptile we know of. So in my mind it doesn't make sense to believe in microevolution and not into macro, unless you are saying you believe what I first said about a guy in the clouds putting life as we see it today on earth in basically the same form it is with only a little room for evolving into what it looks like today. Those tiny bits of life evolved hugely over millions of yrs to all the glorious complex varieties of life we see today.

Answer 3

Yes, Macro, is more easily explained than micro-evolution.



The macro-stuff happens on the big scale, in the environment, with each living creature, in it's struggle to survive. Weather and food supply, for example happen in the Macro-part of evolution.



The micro-evolution happens inside the cells, the DNA, and genes. Some scientists believe that cells themselves may mutate, more often, when the species is threatened by the confinement.

Mutations speed up the evolutionary process.



For example, the feather creation thing, may have started with excess cells, and then when climate changed dramaticly, like a "little ice age", that created forces inside the cells to change excess scales into more "heat retaining" feather-like covering on animals, that eventually became modern birds, after this mutation.



It's all intelligent guessing, for sure, on micro-levels, because the animals and plants that it happened to, died millions of years ago.



But, we can compare similar changes occuring today, with plants and animals, when we notice old species, all of a sudden producing a "new species". New species are being discovered almost every day, somewhere.

Answer 4

you seem to think that mutations can only produce so much change... i think that's where your problem is lying...





"I read somewhere that a mutated gene for hair in a human will change it to brown, red etc but the hair will not change into feathers for instance."

a mutation to the COLOR GENE will do this... a mutation to the STRUCTURE GENE might...

i don't know where you read this but it sound like they were trying to be deceptive about the potential for change that lies in mutation





constructive criticism?

if you're trying to make sense of evolution, start by reading/talking/listening to people who think evolution DOES make sense (i.e. NOT creationists)

if evolution doesn't make sense to someone, they can't explain it in a way that makes, or seems to make sense

if evolution does make sense to someone, they can explain it in the way that makes sense to them, and you can determine if it makes sense to you or not, instead of just being fed a nonsensical version from the get-go





i see secretsauce has beaten me in my criticisms... fair enough, i first heard them from him afterall...

Answer 5

Why do we see so many dinosaur bones and skeletons , many fully intact. And many of these remains are huge and yet so many survived fully intact and yet. They died out millions of years ago? But mankind is still here, and all the bones found, professed to be cave men , put all together would only fill one coffin. And I am not aware of even one fully intact "cave man" Even Darwin said we should see a clear progression of evolving from ape to man. But that is not the case . There is only one coffin full , if all put together. Many , many dinosaurs and a handful of professed neanderthal remains. Why is that? Maybe because the Bible is telling it as it truly happened. We were really were created and are in fact going downward from perfection , not the other way around. To me that alone should tell the tell . We should see far more apelike man skeletons that dinosaurs but the opposite is the case. google problems with "evolution" "carbon dating"

Answer 6

I can explain macro-evolution. Macro evolution is the description of evolution of a large time frame and micro refers to the variation between each generation. Well it is really a creationist thing. In reality there is no such thing as macro and micro evolution and they simply refer to evolution in larger or smaller time frames. Creationists often try to say that micro evolution can exist but not macro...this is obviously a lack of logic.

Answer 7

It didn't start as feathers for birds. Probably Began with some sort of cartilage (the material used to make feather bases) that slowly grew out to help with flying. I imagine the feathery part would have come later.

Answer 8

Absolutely not.



There is much confusion about the difference between Natural Selection and Evolution.



NS is an observed fact as everyone agrees. Examples are Darwin's finches, lions/tigers (which despite being different species, can interbreed and are the same 'kind').



E (goo-to-you) is the hypothesis that animals can change into different kinds of animals by means of natural selection working on genetic mutations.

These alleged mutations need to have added vast amounts of genetic information. However no such genetic mutation has ever been observed. Mutations are information neutral or lossy.

'But E is too slow to see' protest the Eists. Well then it's not observable and not worthy of being even called a theory. In any case, time is the enemy - mutations are resulting in the degradation of the gene pool - that is observable.



Many evolutionists (deliberately?) mislead people by calling NS evolution and then claiming E is proved.



You don't find Creationists being so sloppy :)



"But what about beneficial mutations?" the evolutionists might say.

There are indeed some mutations which could be considered beneficial - for example wingless beetles on a small island have the benefit of not being blown to sea. But the key point is not whether there is any benefit, but whether there is any new genetic information. Evolution requires a massive net increase in information. All observed mutations are information neutral or lossy (like the loss of beetles wings). The oft-quoted examples of evolution are like this, or simply natural selection: sickle cell anaemia, peppered moths, bacterial resistance, fruit flies, etc. The next thing that a naive evolutionist may claim is that gene duplications add information. This is not so. It adds DNA, but not new information. That would be like saying that a book with one page duplicated has more information in it. It clearly does not.



Mutations are information neutral or lossy. Notice that all examples of evolution provided by evolutionists fall into this category: Galapagos finches, peppered moths, wingless beetles, bacterial resistance, sickle cell anaemia, dog varieties, fruit flies, etc. It is simply not good enough to provide these as examples of proof that anything has evolved into anything else. These are examples of devolution.



Hair is a good example of a mutation resulting in a loss of genetic information - it is devolution

http://creation.com/how-we-got-red-hair-it-wasn-t-by-evolution

Answer 9

mutations are simply alterations in the genetic code of an organism. Some have observable effects on the organism's phenotype and others have no effect at all (silent mutations), however all involve the alteration of the organism's original genetic template (sometimes the genetic code of a gamete is mutated, leading to a mutation in its offspring--should that gamete successfully produce an organism).



The argument/example provided isn't really a good one (hair into feathers), as the evolution of feathers in dinosaurs did not result from one (or a few) mutation(s) over the course of a short amount of time; it was the product of millions of years of evolution (and mutation-based novelty) acting on, what was probably first an adaptation in insulation on smaller dinosaurs. The evolution of feather structures is thought to have proceeded from simple hollow filaments through several stages of increasing complexity, ending with the large, deeply rooted, feathers with strong pens (rachis), barbs and barbules that birds display today. The first feathers likely appeared in the late Jurassic (or even much earlier, as some data/scientists suggest) with conclusive evidence dated back about 124 mya (early Cretaceous). Considering all of this, the comparison of human hair color (and possible mutation-based change in color) change to the evolution of feathers is not a very good one but one commonly made by those less familiar with the mechanics and nature of evolution.



Evolution takes millions of years and cannot be (even remotely) compared to small changes within a population occurring over only a few generations. To further confuse the issue among lay-people, other, less noticeable, mechanics are at work at the molecular level (see link) to further increase novelty (mutations/genetic alterations), and may be responsible for much of the plasticity seen in the genetic codes of many organisms--molecular evolution also. Many of the concepts associated with molecular evolution are somewhat complex and involve a firm understanding of genetic/biological concepts but, at their root, involve genetic drift, neutral (or silent) mutations, and other concepts that can be reviewed on wikipedia (or in a textbook).



As in the case with feathers, most evolutionary "innovations" take millions of years, and often start out with a different purpose than they later serve (a phenomenon known as exaptation). This can be illustrated by the aforementioned feather's initial function (probably) as an insulating material, or how early fishes' gas bladder evolved into lungs.



A misunderstanding of mutation is relatively commonplace among anti-evolution literature as many of the concepts involved (and addressed above) require more than an hour of research (the amount of time most anit-evolutionists seem to give to understanding the field they so oppose) but are fully rooted in fact and have been demonstrated countless times.



A better understanding of these concepts can be obtained by reading the final grouping of links attached...as they cover scientific support for evolution, molecular evolution, and other related concepts. The final link is a long-term study in which E. coli populations underwent observed and recorded evolution in response to laboratory based environmental alterations--ie evolution was unequivocally demonstrated in populations of bacteria.



EDIT:

Though variation (allelic variation) is already present in populations, mutations are an ever-occurring fact of life (many cancers are the product of mutation induced within the lifetime of the suffering organism, albeit within somatic cells). To understand some of the underlying principles which generate novelty within evolution an understanding of molecular evolution is required (hence the comprehensive linking). The "design" element of evolution is largely the product of natural selection, as most death-inducing events are external (products of the NATURAL environment), while the forces that generate such novelty are often internal and external to the organism (again, see molecular evolution, specifically transposable elements, silent mutations, and the nearly neutral theory of molecular evolution). If you don't care to read the provided links I can do little for you, as ultimately the effort must come from within--should you actually wish to understand these concepts.



In response to chas_whatever: Devolution is a failed concept (http://en.wikipedia.org/wiki/Biological_devolution).

Answer 10

>"I read somewhere that a mutated gene for hair in a human will change it to brown, red etc but the hair will not change into feathers for instance."



A *single* mutated gene will not change a human hair into feathers. No.



But first, nobody thinks that feathers evolved from human hairs.



And second, nobody thinks that features evolved with a *single* mutation.



So wherever you read that is using a 'straw man' argument ... misrepresenting evolution in an absurd way, and then saying "see, evolution is absurd."





>"If we take the example of evolution this would mean that the environment or nature would have to perform genetic engineering. "



Nope. Mutations are happening *all the time*. The vast majority of mutations are neutral ... they have little or no effect on the organism, and neither help nor hurt survival. But mutations spread into the population anyway ... a process we call 'genetic drift'. (For example, green eyes confers neither benefit nor harm to survival, and yet a significant percentage of people have green eyes.)



So these mutations accumulate in the gene pool. Tens of thousands of tiny, quiet mutations that change a protein here, an enzyme there, a slight change to a structure here, a slight modification to hair color there.



But if over time, some *combination* of these tiny mutations *together* starts to confer some tiny benefit ... then that set of mutations will start to spread into the population a little more rapidly. Why? Because those individuals who have that particular set of mutations make more babies, and they make more babies of their own, and so on for generations. That is natural selection.



And once a new trend like that starts producing benefit, then it can accelerate rather quickly. Something as seemingly 'radical' as the evolution of feathers from scales can occur via the accumulation of a few hundred genetic mutations over a few thousand generations.



Again, nobody thinks that it is a *single* mutation can produce such a radical change. And second, the environment is not having to manufacture these mutations on demand ... many of them happen anew, and many of them are already floating around in the gene pool perhaps centuries before they do anything useful when they occur in certain *combinations*.



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>"These things puzzle me after I read an article by Babu G. Ranganathan's Articles on Religion and Science."



Articles by anti-evolutionists are *designed* to leave you "puzzled" about evolution.



My only advice to you is to keep the goal of UNDERSTANDING in your sights. If you want to evaluate evolution honestly, you first have to UNDERSTAND it correctly.



In other words, the world's scientific community are obviously not, as a group, stupid people. So the question should be WHY does evolution make so much sense to them that almost ALL scientists consider evolution to be a CORE concept of modern biology.



I am not saying that the fact that they are scientists makes them *right* ... people like Ranganathan (a conservative Christian creationist with no science background whatsoever) may actually be correct and all the world's scientists are wrong. But you cannot make that assessment honestly until you understand WHY, in their words, scientists overwhelmingly support evolution.



So your assessment of evolution should happen in two phases:



Phase 1 - Understanding: Seek to UNDERSTAND evolution the way scientists who support it understand it. If it makes sense to them, then you should understand WHY it makes sense to them.



Phase 2 - Evidence: Only after you really UNDERSTAND it, should you seek out evidence for or against it. If evolution does not even *make sense* to you, then there is no point in looking for evidence of something that doesn't make sense.





During Phase 1, I recommend reading sources by people like Dawkins who accept evolution and explain it well.



Only during Phase 2 should you start reading the Creationist literature.



If you start reading Creationists during Phase 1, then you are guaranteed to be confused and puzzled. Since their goal is not to "explain" evolution, but to *refute* it, they would like nothing more than for evolution to make no sense to you.



So whenever you feel that 'puzzled' feeling, pay attention to it. Chances are you are reading someone who is *TRYING* to leave you puzzled.