![]() Most of these hands-on exercises, though, focus on a single evolutionary force, neglecting the interaction between selection and drift that is usually explored in computer simulations (Populus, Alstad 2007 PopG, Felsenstein 2008). Several educational resources have been developed to demonstrate the significance of genetic drift or natural selection (see McComas 1998 Staub 2002 Heim 2002 Young and Young 2003). ![]() Finally, the idea that the genetic drift (i.e., chance) may overcome the directional force of natural selection is counterintuitive and is thus difficult to explore in the classroom. Third, theoretical foundations that support neutralist expectations have a deep mathematical basis that makes genetic drift conceptually even more difficult to grasp (Lenormand et al. Second, although many beautifully detailed examples are available to illustrate natural selection (Darwin 1859 Lauer 2000), genetic drift is abstract by nature and is not directly observed. First, when addressing topics related to evolution, the teacher is bound to face some antagonism and hostility in the classroom (Alters and Nelson 2002 Johnson et al. There are many reasons for this recurring neglect. The intuitively appealing force of Darwinian selection was to be viewed as an exception at the molecular level (Kimura 1985 Ohta 1992).ĭespite its importance, however, genetic drift is constantly neglected and often dismissed as an evolutionary force in general biology textbooks (Hammersmith and Mertens 1990 Linhart 1997) and even by professionals in the field (Staub 2002 Nelson 2007). Random genetic drift was not only important it was the chief force governing molecular evolutionary change. Many decades after the publication of The Origin of Species, however, Motoo Kimura sketched a different portrait of the pace of evolution at the molecular level (Kimura 1954, 1968). Professional biologists are eager to dazzle students by explaining the wonderful adaptations that made a particular species possible, starting with the classics: the giraffe’s neck and Biston betularia (Lauer 2000 Scott 2004). Today, natural selection is one of the most influential and pervasive concepts in the biological sciences (Besterman and Baggott 2007). Charles Darwin’s brilliant insights on evolution by natural selection have not been overlooked. Hence, the concept that evolution involves changes in the genetic composition of a population through time is extremely important. ![]() The evolutionary theory is the unifying principle in biology.
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