Hybridization and Polyploidy

The beginning of life on earth is unclear. However, scientists have made great progress in discovering aspects that help explain our existence today. Charles Darwin, for example, made profound changes in human thinking when he published On the Origin of Species in 1859. Through research, experimentation, and dedication, he successfully laid the ground work for the theory of evolution (Quammen, 2006). According to Darwin, the theory of evolution entails the belief that populations, by means of natural selection, change from one generation to the next. By increasing diversity, natural selection allows for the survival of species that are better adapted to their environment (Darwin, 1859).

Species are usually classified based on their ability to interbreed and produce fertile offspring (Templeton, 1989). When two diverged genomes are combined into a common nucleus, the offspring is known as a hybrid (Salmon et al., 2005). Hybrids can result from interbreeding between two animals or plants of different subspecies (intra-specific), species (interspecific), genera (intergeneric), or the very rare interfamilial. Take Hercules, the liger, for example, its parents belong to the same genus but are of different species (Mott, 2005; Shankaranarayanan et al., 1997). Though not much is known about the evolutionary importance of hybridization in animals, there are several instances observed among plants. Hybridization not only serves as a source of new variation but also the start of new species in plants (Mooney and Cleland, 2001).

Polyploidy is the condition where an individual has three or more sets of chromosomes. Although the effects are comparable, the composition and causes for polyploidy differ. When an offspring’s chromosomes come...

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