What Is Microevolution

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Microevolution refers to varieties within a given type. Change happens within a group, but the descendant is clearly of the same type as the ancestor. This might better be called variation, or adaptation, but the changes are "horizontal" in effect, not "vertical." Such changes might be accomplished by "natural selection," in which a trait within the present variety is selected as the best for a given set of conditions, or accomplished by "artificial selection," such as when dog breeders produce a new breed of dog.
The small or microevolutionary changes occur by recombining existing genetic material within the group. As Gregor Mendel observed with his breeding studies on peas in the mid 1800's, there are natural limits to genetic change. A …show more content…
This list will include the variety of beak shape among the finches of the Galapagos Islands, Darwin's favourite example. Always mentioned is the peppered moth in England, a population of moths whose dominant colour shifted during the Industrial Revolution, when soot covered the trees. Insect populations become resistant to DDT, and germs become resistant to antibiotics. While in each case, observed change was limited to microevolution, the inference is that these minor changes can be extrapolated over many generations to macroevolution.

In 1980 about 150 of the world's leading evolutionary theorists gathered at the University of Chicago for a conference entitled "Macroevolution." Their task: "to consider the mechanisms that underlie the origin of species" (Lewin, Science vol. 210, pp. 883-887). "The central question of the Chicago conference was whether the mechanisms underlying microevolution can be extrapolated to explain the phenomena of macroevolution and it was concluded that the answer was no.

Thus the scientific observations support the creation tenet that each basic type is separate and distinct from all others, and that while variation is inevitable, macroevolution does not and did not happen based on the evidence we are given to …show more content…
They say that although no one has been around for that long to observe it there is no reason to believe it isn't possible given a certain amount of time. They even go as far as to say that macroevolution is supported by the fossil records. In a recent statement Dr. Andrew Schnabel said that the “Evidence supporting evolution is mountainous” and mentions the fossil record as support for evolution. This is simply not the case for macroevolution, the fossil record is actually one of its greatest weaknesses. If macroevolution were true, we would expect to find billions of transitional forms showing one type of organism changing into another. Instead we find all kinds of fully formed organisms and not one undisputed transitional fossil. Dr. Schnabel declares it to be a fact that all life evolved from single-celled organisms. If macroevolution were true, we would expect to see it happening today and expect to be able to conduct experiments that prove it. But no one has ever observed it, although as scientists in favour of macroevolution state that, as said before, the process is only possible over many millions of years of micro
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