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Just as it sounds.

2006-09-25 09:02:42 · 6 answers · asked by Azure_dragon 1 in Science & Mathematics Biology

6 answers

These are not really technical terms; they are uncommonly used in science.

"Micro" means small, "macro" means large.

Microevolution applies to small changes, Macroevolution means large changes.

Macroevolution sometimes means the production of new species; sometimes it applies to large scale trends over long periods of times.

The mechanisms are essentially the same - these are not different "kinds" of evolution, they just refer to different time frames.

2006-09-25 09:52:51 · answer #1 · answered by Zhimbo 4 · 0 0

There really isn't any difference. It's terminology used by people who don't want to accept that new species evolve, but who also recognize that they simply can't deny the changes that occur in living things over time. So they take a compromise stance. They allow that changes can occur within a species (so-called "microevolution"), but deny that such changes can ever result in formation of a new species ("macroevolution"). In other words, if a species accumulates ten thousand changes over several million years, we have to still consider it the same species it was before, even though it is completely unlike the original species from which it evolved. Common sense dictates that minor changes, if allowed to continue over a very long period of time, will result in cumulative change that is major. And if the resulting organism is sufficiently different from the original organism, then it only makes sense to call it something new. A new species.

2006-09-25 10:46:22 · answer #2 · answered by PaulCyp 7 · 1 0

From Wikipedia:

"However, microevolution and macroevolution both refer fundamentally to the same thing, changes in allele frequencies, and the scientific controversy is only about how those changes predominantly occur. Either way macroevolution uses the same mechanisms of change as those already observed in microevolution."

2006-09-29 04:43:49 · answer #3 · answered by Take it from Toby 7 · 0 0

for a description of Micro evolution, do a google search for "Culex molestus" the London Underground Mosquito.

macro evolution would be something like the Polar Bear - Ursus maritimus - which became a seperate species as recently (in evolutionary terms) as 10,000 years ago

2006-09-25 09:10:21 · answer #4 · answered by Vinni and beer 7 · 0 2

Well you cant get macro chips can you.

2006-09-25 09:05:11 · answer #5 · answered by mr_sister_uk 3 · 0 4

Macro vs. Micro Evolution

Charles Darwin sparked a revolution in scientific thought with the publication of his book, The Origin of Species, in 1859. With his concept of evolution by natural selection, Darwin attempted to render invalid the biblical idea that "every living thing produces life after its own kind."

In the first half of Species, Darwin cited evidence for "micro-evolution," or changes on a small level between species. His discovery of the several different types of finches on the Galapagos Islands with similar characteristics, derived from a common ancestor, comprised his evidence for micro-evolution. The 14 different species of finches vary according to plumage, size (from the size of a sparrow to that of a large blackbird), beak morphology, behavior and environmental habitat. They were each very different, yet closely related.

From this observation, Darwin then extrapolated his explanation for the origin of life forms from a common ancestor, or "macro-evolution." He used the evidence from the first half of his book on micro-evolution to suggest that the same mechanism could produce all life forms. However, this concept of macro-evolution is not supported by modern scientific evidence. Although we can explain and understand the mechanism behind micro-evolution, we still can only theorize about possible explanations for macro-evolution - since it has no scientifically valid occurrences.

The "Evolution" of Poodles and Chihuahuas?

The concept of micro-evolution - or diversification of species - is a fact of nature. Species do vary and change, but only on a small scale. We have many examples of Darwin's finches and even the breeding history of dogs which supports the notion of micro-evolution.

Micro-evolution was first understood when George Mendel demonstrated the variation within species based on genetic mechanisms. By Mendelian genetics we see the various dog species, which range from the St. Bernard to the chihuahua. The concept of micro-evolution is widely accepted today and supports the biblical notion of life reproducing after its own "kind." In other words, it is accepted in scientific circles that all the different types of dogs most likely descended from a common canine ancestor.

Evolutionists, however, have expanded the model to suggest the origin of the universe, the origin of life from non-life, the origin of amphibians from fishes, the origin of birds from reptiles, and so on. Scientists have many theories of the mechanisms behind macro-evolution, but none of them have any direct evidence. The theories are merely extrapolations from what can be seen on the smaller scale.

This extrapolation is scientifically unjustified. The underlying logic behind this premise is similar to plotting the fastest times man has run the mile over the years, and then predicting that someday man will run a two or three-minute mile. Anyone realizes that there are limits to valid extrapolation. Likewise, Darwinian macro-evolution is undergoing tremendous scrutiny in scientific circles because of the lack of evidence.

When Did the Fish Sprout Legs?

When one examines the historical record of life, we find the absence of transitional forms between the major life groups such as fish and amphibians or reptiles and birds. The fossil record has failed to yield the host of transitional forms demanded by the theory of macro-evolution. Rather, the fossils show an abrupt appearance of very distinct groups of animals.

Take, for example, the supposed"fish-to-amphibian" transition. The general assumption has been that the earliest amphibians evolved from the order of fish, the Rhipidistia. However, there are major differences between the earliest assumed amphibians, the Ichtyostega, and its presumed fish ancestor. The differences are not simply a few small bone changes but are enormous structural differences as can be seen in Figure 1.

The first amphibian had well-developed fore- and hind limbs which were fully capable of supporting terrestrial motion. The transitions between the two are strictly hypothetical, and no transitional fossils have ever been found ... only imagined and artistically drawn. The mechanism for the supposed macro-evolution of the fish to the amphibian is purely hypothetical.

This lack of transitional forms occurs between all major groups of life. Hypothetical transition forms are drawn to show the change from a reptile to a bird but the fossil record has no evidence that this has ever occurred. Even the closest known intermediate, the Archaeopteryx, was a fully developed bird with the capability of flight like modern birds. Darwin's idea of micro-evolution of the finches can provide no explanation or support for the notion of birds evolving from reptiles. One cannot extrapolate from micro-evolution to macro-evolution when scientific evidences do not provide any support for it.

Evolutionists realize that the fossil record challenges the very notion of macro-evolution. As leading evolutionist and paleontologist Stephen Jay Gould stated: "All paleontologists know that the fossil record contains precious little in the way of intermediate forms; transitions between major groups are characteristically abrupt. The extreme rarity of transitional forms in the fossil record persists as the trade secret of paleontology. We fancy ourselves as the only true students of life's history, yet to preserve our favored account of evolution by natural selection we view our data as so bad that we never see the very process we profess to study."1

When looking back through the history of life as recorded in the earth, we find no evidence suggesting the change from one major group to another. The fossil record suggests micro-evolution as Darwin did, but shows no evidence for macro-evolution. We do not have any fossil group which can claim to belong to the ancestor of another major group. Each fossil group has retained its unique and distinct structural and physiological characteristics throughout its life history.

The origin of life has long been described by the tree of evolution, with major groups branching off from common ancestors. Unfortunately, the branches and gaps between kinds of life are so vast and great that they cannot be considered part of the same tree. The description of the fossil record could be more accurately summarized by a forest of trees rather than just one tree of life. We observe the abrupt appearance of different life forms and have witnessed the diversification of life within those kinds. We can observe micro-evolution taking place from the first organisms within each kind. But the genetic variation we see occurring today occurs only in narrow limits.

The fossil record actually supports the model of creation. The Genesis account of creation states that God created the various kinds of plants, birds, fishes and animals on earth. From the creation model, one would expect to see an abrupt appearance of life forms as well as distinct and separate groups. The fossil record shows exactly that, not a history of gradual change from one major kind of life to another.

The entire theme throughout the book of Genesis is that life reproduces after its own kind. Darwin's finches still reproduce finches. It is a testimony to the creativity of God that He has created so many different forms of life, and even placed the great genetic potential for variation within the first creatures. Natural selection over the years has only drawn upon that great genetic potential as Charles Darwin observed. Natural selection brings out the diversity of life but cannot create new major groups of life as macro-evolution would postulate.

2006-09-25 09:06:27 · answer #6 · answered by SAB 3 · 1 6

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