What is the distinction between microevolution and macroevolution?

Answer 1

microevolution - small changes over short periods of time, typically within species
macro - large changes, over long ("geological") periods of time, creating new species

species have a clear definition - group of animals who can mate between each other and produce _fertile_ offspring (mules are infertile, so horses and donkeys are two different species)

Answer 2

From the point of view of rational thought and biology, none.

From the point of view of those who feel threatened by the facts, micro-evolution is change 'within' a species and macro-evolution is change 'between' species.

What the latter group misses is that the concept of 'species' is more of a human construct and not a strictly biological one, moreover one geared towards looking back at the result of evolution, rather than forward to its development. Using species alone to talk of evolution, as micro- and macro-evolution does, is a bit like using photos of an arrow in flight to talk about its actual motion - not entirely useless, but with a non-trivial amount of relevant information lost. More to the point - at any given point in time, all members of any reproductively isolated (and thus evolving) population are the same species as one other, as their parents, and as their children, just like in any photograph, the flying arrow is in the same spot.

Put otherwise, a large change is nothing but a very large number of small changes put together. I.e. 'macro-evolution' is an unavoidable logical necessity of 'micro-evolution.'

Answer 3

Really, not much other than time. Macro evolution is simply micro-evolution extended through time.

Creationists wackos try to distinguish the the two so they can deny the obvious consequences of what they see happen before them. Most of them see obvious changes and still deny that speciation could happen (even though it has been observed many times).

There is no know mechanism that would prevent macro-evolution and all available evidence confirms it.

I doubt one of them who answer this question will look at the website I provide but here it is: