Sexual vs Asexual

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Biologist today still finds “The evolution of sex” to be the biggest questions up for debate. Despite the obvious benefits, sexual reproduction poses more costly and inefficient means of reproduction. Asexual reproduction does not pose any costly means when reproducing nor does it have to combine its genetic material with another male or female. Asexual organisms have the ability to grow at twice the rate of sexual reproducing organisms. A sexually reproducing population must, in fact, produce both sexes, which leads to only 50% of them able to give birth on their own. Contrasting this with asexual reproducing populations, 100% of their offspring potentially can give birth. This analogy is called the two-fold cost. So the question remains, given the advantages of asexual reproduction, why do most organisms prefer reproducing sexually? The question presented had been called the paradox of sex. There are multiple mechanisms required to try to explain the emergence and maintenance of sexual reproduction. “Of the many explanations for the prevalence of recombination and sex that have been posed, a number of them are considered to be most likely”. (Kondrashov 1993). Muller’s Ratchet, adaptation to fluctuating environments and, an increase rate in adaptation might just be the answer to how sex evolved. Can these theories be good enough to outweigh the cost of sex? Or will it take a combination of all theories to solve the biggest mystery of all, sex?

Over the course of several years, evolutionists have tried to explain the actuality of sexual reproduction to promote genetic variability. However, this explanation is not only faulty but poses a few disadvantages as well. Sexual reproduction happens by the formation of g...

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...roach by combing all three of these mechanisms might be required to fully balance the two-fold cost of sex. (West, Lively, Read) The mutation accumulation theory requires mutation rates to be high, (Kondrashov, 1993 Deleterious mutations and the evolution of sexual reproduction), each deleterious mutation will lead to a decrease in log fitness then the previous one, and population sizes have to be large for it to work properly. Even though some models may not be able to fully explain the two-fold cost of sex, it just might play an important role. A pluralistic approach helps “shift the emphasis of empirical work away from the search for discriminating prediction to parameter estimation”. This approach also “emphasizes environmental and mutational mechanisms interact synergistically in a number of ways and outweighs each other’s weaknesses”. (West, Livley, Read)

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