Darwinists believe that all life is genetically related and has descended from a common ancestor. The first birds and the first mammals are believed to have evolved from a reptile; the first reptile is believed to have evolved from an amphibian; the first amphibian is believed to have evolved from a fish; the first fish is believed to have evolved from a lower form of life, and so on, until we go all the way back to the first single-celled organism, which is believed to have evolved from inorganic matter.
The very first single-celled organism did not possess all of the genetic information for a human, so in order for humans to have ultimately evolved from a primitive single-celled organism, a lot of genetic information had to be added along the way. Change resulting from the introduction of new genetic information is macroevolution.
The reason why macroevolution is controversial and remains theoretical is that there is no known way for entirely new genetic information to be added to a genome. Darwinists have been hoping that genetic mutation would provide a mechanism, but so far that has not been the case. No truly useful mutations have ever been observed.
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. Microevolution is an uncontroversial, well-documented, naturally occurring biological phenomenon.
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 . . . the answer can be given as a clear, 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.
When Creationists say they don’t believe in evolution, they are not talking about microevolution, they are only referring to macroevolution.
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