Do the words 'microevolution' and 'macroevolution' have any real validity in biology?

Question

Or are they just terms invented by 'god-of-the-gaps' style creationists?

Answer 1

Microevolution and macroevolution are different things, but they involve mostly the same processes. Microevolution is defined as the change of allele frequencies (that is, genetic variation due to processes such as selection, mutation, genetic drift, or even migration) within a population. There is no argument that microevolution happens (although some creationists, such as Wallace, deny that mutations happen). Macroevolution is defined as evolutionary change at the species level or higher, that is, the formation of new species, new genera, and so forth. Speciation has also been observed.

Creationists have created another category for which they use the word "macroevolution." They have no technical definition of it, but in practice they use it to mean evolution to an extent great enough that it has not been observed yet. (Some creationists talk about macroevolution being the emergence of new features, but it is not clear what they mean by this. Taking it literally, gradually changing a feature from fish fin to tetrapod limb to bird wing would not be macroevolution, but a mole on your skin which neither of your parents have would be.) I will call this category supermacroevolution to avoid confusing it with real macroevolution.

Speciation is distinct from microevolution in that speciation usually requires an isolating factor to keep the new species distinct. The isolating factor need not be biological; a new mountain range or the changed course of a river can qualify. Other than that, speciation requires no processes other than microevolution. Some processes such as disruptive selection (natural selection that drives two states of the same feature further apart) and polyploidy (a mutation that creates copies of the entire genome), may be involved more often in speciation, but they are not substantively different from microevolution.

Supermacroevolution is harder to observe directly. However, there is not the slightest bit of evidence that it requires anything but microevolution. Sudden large changes probably do occur rarely, but they are not the only source of large change. There is no reason to think that small changes over time cannot add up to large changes, and every reason to believe they can. Creationists claim that microevolution and supermacroevolution are distinct, but they have never provided an iota of evidence to support their claim.

Answer 2

None whatsoever.

They were introduced by orthogenetecists in the 20s. These individuals adhered to the idea that special mechanisms were required for speciation. This has not been supported since the 30s. Any distinction between "microevolution" and "macroevolution" is a false one; the basic mechanism of all evolutionary processes is the same: random mutation and natural selection. Whether we're talking above or below the speciation level (which is a rather arbitrary line) is irrelevant.

Answer 3

Microevolution is macroevolution in the short term. Macroevolution is the inevitable result of microevolution in the long term. They are the same process. Only the time frame is different.

Answer 4

i imagine genuinely the "mission" is with tremendous speciation(sp?) in my view my view is "Guided evolution" the position God used evolution because the established technique for starting to be the shape of life on the earth. yet tweaked and helped it alongside on some spots, now this isn't scientifically provable or some thing, yet genuinely it really is the way for me, to get around the actual shown reality that some factors of evolution requiring unreasonably not likely, acceptable coincidences to artwork because it has. in case you had to pin down a medical "destroy factor" the position introduction-ish perspectives have an difficulty with... IMO it might probable be contained in the realm of "subphylum" .. the position it branches from "each little thing with a spnial cord" to beasts vs fish, ect... i imagine in case you're taking genesis in a inteperetive metaphorical way, it easily DOES go by a series of massive bang, formation of the cosmos, and progression of life, by skill of evolution. and this form of steps as listed is the dissimilar separation between sea life and land-depending life. in case you do not take "days" actually, then this flows together very complimentarily. some will be able to take care of the conception of the human variety being advanced from apes. in spite of the indisputable fact that the conception of human beings and fish having a worry-loose ancestor seems far better bizzare. I do appriciate that in case you look at it step by skill of step over the shape than no particular replace seems that irrational, its better that the collective replace delivers as a lot as too a lot(imo) unlikelyness.

Answer 5

An important note: the changing of one species to another has never been observed. It has been inferred through the use of fossils and artist depiction. Thus, macroevolution remains an unproven theory. Microevolution, obviously, is observed all the time, thus it is a proven fact.

Answer 6

It's just verbage. A way for them to "explain" scientific findings while still believing in creation. It all comes down to numbers...and when you do the math micro and macro are the same exact thing.