Log in
HomeClass Notes1,200,000US530,000

BISC104 Lecture Notes - Lecture 11: Disruptive Selection, Gene Flow, Mendelian Inheritance

38 views5 pages
School
University of Delaware
Department
Biological Sciences
Course
BISC104
Professor
Dr.Patricia Walsh

For unlimited access to Class Notes, a Class+ subscription is required.

Document Summary

Describe the (darwin"s) observations that are the basis for the theory of natural selection. Individuals within populations vary: some of the variation among individuals can be passed onto their offspring, populations of organisms produce more offspring than will survive, survival and reproduction are not random. Explain what is meant by evolutionary fitness: based on the number of offspring you produce, how well a species is able to adapt to and reproduce in its environment. Over generations, the trait can become quite exaggerated (why dachshunds have very short legs) 1 the population had evolved: the evolution of the fruit flies in this experiment was a result of natural selection. Important role in survival and adaptability of species. Why isn"t variation enough: not enough to have an impact on natural selection because is not a genetic trait, ex: hair length can have variation but it is not a trait that is passed on through generations.

Get access

Grade+
$40 USD/m
Billed monthly
Grade+
Homework Help
Study Guides
Textbook Solutions
Class Notes
Textbook Notes
Booster Class
10 Verified Answers
Class+
$30 USD/m
Billed monthly
Class+
Homework Help
Study Guides
Textbook Solutions
Class Notes
Textbook Notes
Booster Class
7 Verified Answers

Related Documents

BISC104 Lecture Notes - Lecture 21: Peppered Moth, Genetic Variation, Selective Breeding
blushchimpanzee719
BISC104 Chapter Notes - Chapter 11: Combination Drug, Selective Breeding, Tuberculosis
pucemallard917
BISC104 Lecture Notes - Lecture 14: Macroevolution, Microevolution
scarletwallaby416

Related Questions

Natural selection and evolution

Correctly complete the following paragraph to explain the relationship between natural selection and evolution.

Terms may be used more than once.

Within a population of fish, ____________ exists in the form of body color. Some fish are orange and some fish are red.

The fish population lives on an orange reef bed. Because of this, fish that are ____________ are able to blend in and resist predation.

Because fish that are ____________ are more likely to blend in and resist predation, they are more likely to survive to reproduce.

Fish produce ____________ offspring which ____________ the genes for body color.

After several generations, one can expect the fish population to have a ____________ portion of orange individuals compared to red individuals.

In this manner, ____________ is driving ____________ .

Choice of words:

natural selection

genetic variation

red

evolution

smaller

many

inherit

larger

orange

few

Describe the theory of natural selection Which of thefollowing BEST describes the theory of natural selection? CHOOSEONE

1 The genetic make-up of apopulation gradually changes from one generation to the next.
2 Living organisms change overtime.
3 Each species produces many moreoffspring than can survive long enough to reproduce. The offspringthat do survive contain genes that are inherited from theparents.
4 There is variation among themembers of a species. Some of this variation is geneticallydetermined and so can be passed on to future generations.
5 Some individuals have genes thatincrease their chances for survival and reproduction. Theseindividuals are more likely to reproduce and pass on their genes,causing their genes to become more common in the nextgeneration.
6 There is a struggle for existenceamong the members of a population.

1. What is the difference between the different patterns ofselection: directional, stabilizing,anddiversifying?

2. How do bacteria acquire genetic variation and how does thatdiffer from the mechanism by which humans acquire variation?

3. What were the key observations made by Darwin to develop thebasic tenants of the theory of evolution? Has thistheory been tested?

4. What are the most common misconceptionsabout evolution and why are they not valid arguments againstevolution?

5. The key component of the theory of evolution isnatural selection. Define this process. Why is itcommonly known as “survival of the fittest”? What are examples offactors (selective pressures) that drive evolutionof populations?

6. What is the indirect evidence of evolution? What arehomologous and analogousstructures? What is convergent evolution?How does similarity of proteins between different species supportthe idea of evolution?

7. Be able to explain why the following statement is true:Natural Selection works on individuals while evolution works onpopulations over generations. Or to put it another way: Individualsdo not evolve, populations do.