Peppered Moth
Microevolution or macroevolution?
For years the story of the peppered moth, Biston betularia, has provided one of the best-known examples of natural selection in action. ...
What we do know is that the rise and fall of dark-colored moths, a phenomenon known as
"industrial melanism," remains a striking and persuasive
example of natural selection in action.
What we have to be cautious about is attributing 100% of the work of natural selection in this case to
the camouflage of the moths and their direct visibility to birds.
The peppered moth is another one of those hailed icons of evolution and typical textbook examples.
It is remarkable how people use certain stories to prove this or that.
Industrial melanism plays a role in
creating the circumstances for natural selection to take place.
Now biologists agree that this example shows natural selection causing evolution within a species;
microevolution only.
The [peppered moth] experiments beautifully demonstrate natural selection
or survival of the fittest - in action, but they do not show
evolution in progress, for however the population may alter... all the moths remain from beginning to end,
Biston betularia.
It's a motherfacking moth fact that peppered moths have never changed into anything other than peppered moths. Individuals of each morph interbreed and produce fertile offspring with
individuals of all other morphs; hence there is only one peppered moth species. This is a good example of
natural selection and it's part of
microevolution. Nothing to do with
macroevolution.
Last week, the Manchester School of Art joined forces with the Manchester Museum to host a series of workshops for 10-14 year olds,
exploring the significance of the Peppered Moth within a contemporary context. The aim of these workshops was to find creative ways for young people
to discuss climate change and evolution.
Activities give an introduction to Charles Darwin and his theories of evolution.
Schools typically teach kids that the peppered moth is a prime example of evolution.
What they don't tell kids is that the peppered moth is merely an example of microevolution and has nothing to do with macroevolution.
This is how they make it seem to kids that this is an example that proves the whole theory of evolution.
Of course kids are not left with much space to think about it themselves, they are presented with a story and expected to accept it
within the box of evolutionary thought.
The story of this experimental proof of evolutionary theory made its way into all the biology texts
written since the 1950s when the results of this field experiment yielded such clear results.
Students everywhere heard the story and learned
Oh Happy Day - the theory of evolution was provable!
For decades the peppered moth has been a standard classroom and textbook example of
evolution. Millions of students have learned this "living proof" of
natural selection. The story they have been, and are, being told is most likely false,
or to put it more mildly, filled with half-truths.
This is not because teachers and writers are intentionally lying, or hiding and bending facts,
but because the example is only brought to prove a point, so that complications appear extraneous to the argument.
Such obvious population changes over a relatively short period of time have made the peppered moth a textbook example of natural selection,
but the genetic basis of the rise and fall of the dark form has not been understood.
Previous evidence shows that the dark colouring isn't associated with any of the genetic pathways already known to cause melanism in insects,
and it was unclear whether the moth's dark form had arisen several times or just once.
Evolutionists have always been good at selling their story to the world. Of course most of them will not mention that it has nothing to do with
macroevolution.
It is not even known if there is a genetic component involved in the change of colour.