What is the fundamental difference between the process of Microevolution and Macroevolution?

Question

Also, has macroevolution ever been observed?

Answer 1

The only *fundamental* difference ... is time.

There is no actual dividing line between where microevolution ends and macroevolution begins. Not as far as nature is concerned. The difference is entirely one of how we humans approach the two questions, not in recognizing a *fundamental* difference, a dividing line, between the two in nature.

Microevolution is defined by biologists as "evolution at or below the level of the species."

And macroevolution is defined by biologists as "evolution at or above the level of the species."

Note that the phrase "at the level of the species" is part of both definitions. There is overlap. And this is at the speciation event (the split of one species into two species). In other words, speciation can be studied quite well at the microevolutionary level (it can be duplicated in a lab), but is also necessary for understanding macroevolutionary concepts (like the branching of species, genera, and other classes of species).

When I say it is a difference in *approach*, and this is related to time, what this means is that microevolution occurs in timescales of a few years ... and thus is directly accessible to human scientists by direct experiment. Macroevolution occurs on timescales typically in the thousands to millions of years, and is thus accessible to indirect methods of *observation*. Some creationists try to exploit this difference by trying to say that this therefore means that there is no evidence for macroevolution *at all*, or even that it doesn't qualify as a science *at all*.

This is, of course, rubbish. We use indirect observation all the time, and is a perfectly valid way of approaching science. Observation is the backbone of many sciences such as geology, astronomy, astrophysics, climatology, meteorology, anthropology, archaeology, paleontology, and large parts of theoretical physics. Basically *any* process that involves the very large (like stars and galaxies, or even hurricanes), or the very old (geologic processes, long-term evolution, or even archaeology) are not subject to direct experiment, and thus rely on the perfectly valid technique of observation.

The bottom line is that nobody has found any hard separation *in nature* between what we humans call "microevolution" and "macroevolution" for convenience of study.

Macroevolution is just the process of microevolution, on much longer timescales.

Answer 2

In terms of process, there are no fundamental differences between microevolution and macroevolution. The former is a convenient label for small evolutionary changes usually occurring over relatively short timescales; the latter for large changes usually occurring over relatively long timescales. Macroevolution is cumulative microevolution.

Macroevolution cannot be observed any more than you can observe mountains vanishing as a result of erosion. However, you can observe and measure microevolution and erosion and extrapolate the long term result – forwards or backwards in time.

The fossil record shows us that organisms have changed dramatically over time, which allows us to state categorically that macroevolution is a flat fact. This is a rare thing in science and only occurs when the evidence is overwhelming and utterly unambiguous.

Answer 3

> What is the fundamental difference between the process of Microevolution and Macroevolution?
Time and selection.

> Also, has macroevolution ever been observed?
Nope. Macroevolution covers the past 3.5 billion years. Humanity hasn't been around that long.

Answer 4

Microevolution is simply a species adapting to an environment. For example the species of moths might get darker to avoid being eaten or a dandelion might bloom closer to the ground to avoid the lawnmower. This is closely tied to natural selection. The survivors simply breed the new information into the next generation.
Macroevolution has never been observed becuase it is a process that would take hundreds if not millions of years. It is a species actually becoming another species. Growing new organs or apendages. Any examples of macroevolution are skeletal and they are few and far between.

Answer 5

there is no fundamental difference. Which does not mean there are no differences, yes there are, but I would not call them fundamental, though that may be a matter of viewpoint.

Yes what you refer to as macroevolution (which properly is refered to as speciation) has been observed multiple times.

check out this link:
http://www.talkorigins.org/faqs/faq-speciation.html

If you post in biology it would be good of you if you could avoid the terms micro- and macroevolution. They are not biological terms. The terms just refer to perceived change (by human standards) and are pretty much meaningless. A large morphological change could be caused by just pointmutation which means a single mutation, whereas a small morphological change could have required a larger number of mutations. Mutations don't even have to lead to a change in phenotype.

Answer 6

There isn't any. The supposed distinction is sophistic trash posed by anti-evolutionists; with enough micro, you can get as macro as you please. Since evolution is now a proven fact, it doesn't matter anyway.
In the case of human evolution, among the numerous scientific papers on the subject, see: