BIOC16H3 Chapter Notes -Messenger Rna, Ecological Genetics, Phenotypic Trait

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greenherring451

25 Apr 2013

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Document Summary

Ecological genetics is concerned with the genetics of ecologically important traits, that is, those traits related to fitness such a survival and reproduction. The study of the process of phenotypic evolution occurring in present-day natural populations. Ecologically important traits: those traits that are closely tied to fitness or, in other words, are important in determining an organisms adaptation to its natural environment, both biotic and abiotic. Phenotypic evolution can be defined as a change in the mean or variance of a trait across generations due to changes in allele frequencies. The four processes that cause evolution are mutation, genetic drift, migration, and natural selection. Adaptation is the central theme of ecological genetics. An adaptation is a phenotypic trait that has evolved to help an organism deal with something in its environment. Natural selection is the only evolutionary process which leads to adaptation.

Related Questions

An adaptation or adaptive trait is a trait/characteristic that has evolved in a population of organisms which provides a functional advantage. Adaptations increase the biological fitness of a population. Fitness is defined as the ability to survive and pass genes on to subsequent generations. For the purposes of this assignment, you are to choose an adaptive trait common to more than one species. For example, birds and bats both have wings. Write a 2-3 page (500 â 750 words, 12 point font) paper including the following elements. Be sure to compose your work with your own words. Do not copy and paste from any source. Describe what makes this trait an adaptation. Briefly describe how the trait evolved; e.g., mutation, genetic drift, migration and/or natural selection. Be sure to support your answer with evidence. What is the difference between homologous and analogous traits? How does your trait of choice fit either of these descriptions? What is convergent and divergent evolution? Describe whether the trait is a result of convergent or divergent evolution. Use in-text citation and provide source references for at least 3 sources. The textbook can be one source. When citing articles or other types of documents, follow standard guidelines as introduced on "Citing references in scientific research papers".

Which statement about evolution by natural selection isfalse?

Natural selection allows organisms with higher fitness toreproduce more successfully.

Natural selection favors those traits that confer higherfitness in the environment.

Natural selection is a random change in characteristics of apopulation over generations.

Evolution by natural selection affects populations oforganisms, not individual organisms.

An organism's fitness depends on its _____.

ability to survive and reproduce

ability to swap genetic material with other organisms

physical size

ability to mutate

population

Consider the heavily armored stickleback fish population thatcolonized the lake. If all the individuals in that population weregenetically identical, what do you predict would happen when theycolonized the freshwater lake?

The population would increase, as it has increased foodresources.

The population would evolve through natural selection to bebetter adapted to its environment.

The population would decrease due to more juvenile fish beingeaten.

No answer text provided.

Which of the following are adaptations?

Thicker beaks on finches that allows them to eat large seeds,when large seeds are the most abundant.

Less armor on stickleback fish in freshwater that allows themto grow faster to avoid predation.

More armor on stickleback fish in the ocean that prevents themfrom being eaten by larger predators.

None of the above.

All of the above.