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I regularly encounter students who believe humans came from amoebas and when asked why they often say Macro-Evolution has been scientifically proven.

Macro-evolution is defined as evolution at or above the species level, which leads to the problem: Scientific evidence does exist for speciation at the Biological Species Concept (BSC) level, but not for all species concepts and only if a helpful definition is employed. Lions and tigers are considered different species and have been know to reproduce--sometimes with fertile offspring. Therefore, what benefits are there to such a broad category as macro-evolution?

The distinction between lions and tigers is so much smaller than feathered vs. scaled creatures! Surely the current definition of macro-evolution is overly broad and confusing to newcomers. Only the fuzzy edge of the macro-evolution definition has been proven. Proving that 1 inch of a yardstick exists does not prove that the rest does. There is a distinct lack of rigor to the statement that "macro-evolution has been scientifically proven."

Surely the definition of macro-evolution could be chopped in half with the goal of distinguishing between relatively trivial changes (Lion vs. Tiger, but beyond micro-evolution) and relatively non-trivial distinctions (either at and above the genus or the family level). The "trivial" changes could be termed "Middle Evolution" and work something like this:

1.) Middle evolution: evolution at or above the species level, but below the family level.

2.) Macro evolution: evolution at or above the family level.

Substitute the word genus for family in the above definitions if that seems better. I admit that line would be somewhat arbitrary, but would not the term "Middle Evolution" be informative?

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closed as not constructive by Mad Scientist Apr 17 '12 at 6:23

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Two observations: 1. Species speciate. Genera don't generate. 2. Any taxonomic distinction above the level of species is meaningless. –  kmm Apr 15 '12 at 22:56
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Macro-evolution is a nonsense terms as far as biologists are concerned. All it really means is evolution over a long time-period. All the macro/micro/middle is dishonest manufactuvorsey foisted off by liars and deluded individuals. –  Larian LeQuella Apr 16 '12 at 1:21
    
Would not a better term be Mesoevolution? –  bobthejoe Apr 17 '12 at 3:32
    
This is really more of a discussion than a question and not a good fit for this site. –  Mad Scientist Apr 17 '12 at 6:23
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1 Answer 1

The only place that the terms "macro-evolution" or "micro-evolution" are generally used, are in creationist rhetoric. They are not terms used by biologists. This is because there is no need to create distinct categories. In reality there is only "microevolution". Macro-evolution is not a different thing, merely an accumulation of many micro-evolutions.

what benefits are there to such a broad category as macro-evolution?

None. Which is why such a term has been abandoned.

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“They are not terms used by biologists” – that’s not true. They do have a biological meaning … which is of course distinct (but sufficiently similar to cause confusion) from what creationists mean, and has been around long before they started using the term. I try not to use the terms myself due to the confusion that has been engineered by creationists but some biologists do use them. –  Konrad Rudolph Apr 18 '12 at 23:41
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@KonradRudolph I know they have meaning, but that doesn't mean they're used still. Our advancing understanding of evolution has made them irrelevant. –  Preece May 4 '12 at 7:05
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No, they still have meaning and are still used by evolutionary biologists. They have been made irrelevant only insofar as there are other terms that can be used instead, but not because “macroevolution” is an inadequate term (it isn’t, it’s a well-defined, actively studied concept), rather in order to avoid confusion because it’s being misused. –  Konrad Rudolph May 4 '12 at 8:33
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