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Knowledge and Skills Statement

Science concepts--biological evolution. The student knows evolutionary theory is a scientific explanation for the unity and diversity of life that has multiple mechanisms.

the theory in biology postulating that the various types of plants, animals, and other living things on Earth have their origin in other preexisting types and that the distinguishable differences are due to modifications in successive generations

a natural process that results in the survival and reproductive success of individuals or groups best adjusted to their environment and that leads to the perpetuation of genetic qualities best suited to that particular environment

an evolutionary process that leads to the formation of new, distinct species that are reproductively isolated from one another

Research

Dettman, Jeremy R., James B Anderson, and Linda M Kohn. "Divergent Adaptation Promotes Reproductive Isolation Among Experimental Populations of the Filamentous Fungus Neurospora." BMC Evolutionary Biology 8, no. 31 (January 2008): 35.

Summary:  Under ecological speciation, reproductive isolation between populations is predicted to evolve incidentally as a by-product of adaptation to divergent environments. Using the fungal model Neurospora, we founded experimental lineages from both intra- and interspecific crosses, and evolved them in one of two sub-optimal, selective environments. We then measured the influence that initial genetic diversity and the direction of selection (parallel versus divergent) had on the evolution of reproductive isolation.

Research

Tishechkin, D.Yu., and V.Yu. Vedenina. "Acoustic Signals in Insects: A Reproductive Barrier and a Taxonomic Character." Entomological Review 96, no. 9 (December 2016): 1127-1164. https://doi.org/10.1134/S0013873816090013

Summary:  In communities of sympatric singing species, there is a partitioning of communication channels, the so-called "acoustic niches." Within one community, the songs of different species always differ in temporal or frequency characters, i.e. occupy different acoustic niches. The species that do not communicate acoustically due to allopatry, different timing of vocalization, inhabiting different biotopes, or unmatched food specializations can produce similar songs while forming reproductively isolated communities. Song evolution in grasshoppers is more strongly driven by sexual selection than that in crickets.