Evolution: Sexual and Asexual (Essay Sample)
Many organisms that can reproduce both sexually and asexually share a reproductive pattern. When the environment is favorable for growth, reproduction is asexual. When the environment deteriorates, sex occurs. Sexually produced offspring remain dormant until better conditions occur. Which of the theoretical ideas about the function of sex is supported by this observation? And which of the disadvantages of sex are less of a problem?
From the point of view of development, how does the life cycle of a bacterium resemble the life cycle of an elephant? How does it differ?
If a trait is not well adapted to current local conditions, what might be the reasons why it is not, and how might one check to see which of those reason(s) is correct?
In many old texts and in some recent popular articles sex is seen as necessary to provide the genetic variability that will keep species from going extinct when the environment changes significantly. What do you think of this explanation?
Do ideas, agricultural practices, or computers evolve in response to natural selection? What then corresponds to reproductive success and to inheritance? How does cultural change connect to biological evolution? Neither reproduction nor inheritance can be as precisely defined for cultural change as they can for biological evolution, but the analogy is worth exploring.
Evolution: Sexual and Asexual
Usually, organisms have to reproduce as a means of ensuring survival in many generations. Organisms can reproduce sexually, asexually or both. Sexual reproduction has a disadvantage in that it involves a two-fold cost of sex. To explain this, let’s assumes that in a sexual population there arises a mutant female who produces asexually. If the mutant female produces a similar number of offspring, definitely she will produce twice as much offspring as compared to the sexual female. If the offspring inherited the mutation, then they will also reproduce asexually and eventually the mutation will outgrow the sexual population. This indicates that asexual production is advantageous in that it leads to reproduction of more offspring as compared to sexual reproduction. However, most species reproduce sexually because there are some advantages associated with sexual reproduction. It has been demonstrated that sexual offspring have the ability of adapting to changing environment and can persevere unfavorable conditions unlike the asexual offspring.
A number of organisms such as Daphnia magma exhibit both sexual and asexual reproductive pattern. In these organisms, asexual reproduction takes place when the environment is favorable for growth and when the conditions are not very conducive, sexual reproduction takes place. The offspring reproduced sexually remain dormant up to the time conditions becomes favorable (Duncan et al, 2006). This observation supports Fisher-Muller theory which stipulates that under certain conditions, it can be demonstrated that sexual populations have the ability to adapt faster as compared to asexual populations. Since the world is ever changing, sex is more advantageous over long terms. Assume that at two loci possessing alleles A and B new alleles a AND b are privileged when environmental change takes place. Assume that these two alleles a and b arise in the population immediately when the environment change occur. However, both mutations arise most probably in different individuals (Freeman & Herron, 2004). This means that in asexual population alleles a and b will not be brought together within a single individual. Therefore, we can only wait until either alleles a or alleles b fixes in the population, prior to fixing of the other allele form a new mutation. In contrast, when we consider sexual population, alleles Ab and aB individuals can mate and yield ab offspring through recombination. The genotype ab can therefore fix within the population even when mutations a and b did ...
YOU MAY ALSO LIKE
- Midterm Civil WarDescription: Explain the role that faith played in U.S. foreign policy toward the Middle East prior to the Civil War...3 pages/≈825 words | 4 Sources | APA | Social Sciences | Essay |
- Defining Police EthicsDescription: They are conventionally supposed to be the upholders of law and order, the keepers and advocates of morality...8 pages/≈2200 words | 4 Sources | APA | Social Sciences | Essay |
- Organizational DisabilityDescription: Describe your personal experiences with learning disabilities that you observed in an organization you are a part of or were part of....1 page/≈275 words | 3 Sources | APA | Social Sciences | Essay |