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14 Jun 2018

Question 1 A single breeding pair of rabbits is introduced to Australia in 1900. Assume (for simplicity) that each pair can produce 4 offspring each year (2 male, 2 female). Also assume, that all births happen in the last hour of the last day each year and the parents die immediately after offspring are born.

a) How many rabbits are there after 10 years?

b) How many rabbits are there after 25 years?

If they have 20 offspring each year,

c) How many rabbits are there after 10 years?

d) How many rabbits are there after 25 years?

Question 2 Now, assume that rabbits reach sexual maturity instantly after being born and all can reproduce continuously (generations overlap). If each pair has 4 offspring and both parents die by the end of the year:

a)How many rabbits are there after 10 years?

b)How many rabbits are there after 25 years?

Question 3 Now, assume that the carrying capacity of the environment is K=1000. There are 6 offspring, both parents die as before. What is the rabbit population when the growth rate of the rabbits each year is the largest? Use discrete logistic to answer:

a) How many rabbits are there after 2 years?

b) How many rabbits are there after 3 years?

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Casey DurganLv2

15 Jun 2018

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Procedures

From the lab kit, find the piece of colored fabric and pieces of colored foam. Open the fabric and spread it out on a flat surface. Using the paper hole punch and punch template from the lab kit, punch out 30 dots from each of the 10 colors of foam.

Each colored circle represents an individual rabbit of the type known as Rabbiticus hopquickus. A starting population of 100 rabbits that live in a meadow will be used in this experiment. The experimenter will assume the role of a coyote of the type known as Coyotus predacious. Coyotus predacious like nothing better than to feast on a choice specimen of Rabbiticus hopquickus. Normally, the only death in the population of Rabbiticus is due to predation by Coyotus predacious. The piece of fabric simulates a meadow on the island of Darwinia, the only island on which both Rabbiticus hopquickus and Coyotus predacious have been seen. Variations of individuals are characteristic of organisms of the same species.

Begin the simulation by placing 100 rabbits (10 dots each of 10 different colored circles) into a cup. Mix them up by shaking or inverting the container. Scatter the rabbits randomly over the surface of meadow (the fabric).

Begin the simulation. Donât stare at the distribution of the dots on the fabric, but rather look away until ready to begin. Begin by turning toward the fabric and use the forceps to pick up the first dot (rabbit) that stands out. The rabbits (dots) picked up are those that are easiest to see. After a rabbit is selected, immediately look away from the fabric. The captured rabbits should be brought to the coyote den (the cup). Repeat this procedure until a total of 75 rabbits have been captured, remembering to look away from the meadow after each capture. Twenty-five rabbits should remain in the meadow. The object is to capture the rabbit that is first observed when looking at the fabric.

Gently shake the meadow and collect the 25 surviving rabbits. These are the rabbits that will produce the second generation. Divide them into piles according to color. Rabbiticus hopquickus is noted to have both male and female reproductive organs in the same individual and thus can fertilize itself. Each surviving rabbit will now reproduce. For each dot, use the hole punch to cut out an additional three circles (baby rabbits) that are the same color as the parent. Record the number of rabbits of each color in a chart similar to the chart provided, below. Put all of the rabbits (100 total) into the plastic cup, shake them, and disperse them at random on the meadow.

Simulate two more generations of Rabbiticus by repeating Steps 4 and 5 two more times. Keep track of the numbers of each kind of rabbit by making a chart like the one below. The only difference is that a total of 10 colors should be recorded in the chart.

Color	Original Population	1^st Generation	2^nd Generation	3^rd Generation
green	10
purple	10
light blue	10
red	10

When finished with the last round of predation and reproduction, count the color and number of each of the 25 surviving rabbits. Then multiply each number by four to get back to 100 rabbits.

Assume surviving rabbits are all yellow.

Could this population adapt to a new environment where the predominant color is purple? (2 points)

Why or why not? (3 points)

Why did the results come out the way they did? Explain why all of the colors of rabbits did not end up with the same population size. The explanation here should demonstrate an understanding of natural selection.

azurebee320

1.. Polymorphisms for a given trait are relatively common in most species. Discuss the possible advantages or polymorphisms in terms of evolutionary fitness. Be sure to relate your discussion to a specific example. It is also possible that organisms showing more heterozygosity may actually be less fit. Describe one such possible scenario.

2. In the peppered moth (Biston betularia), black individuals may be either homozygous (A1A1) or heterozygous(A1A2), whereas the pale gray moths are homozygous (A2A2). Suppose that in a sample of 250 moths from one locality, 108 are black, and 142 are gray.

3. Retrace the history of primate evolution from early primates to monkeys, apes and hominins. When did some ofthe significant divergences occur (such as between the prosimians and the monkeys or between the chimps and hominins)? What was happening with the continents and the major climatic conditions during these times?What are the major species (including the extinct species) along the human lineage after the split with the chimps and bonobos? Where did many of these events occur on the globe and when?

4. Spencer Wells described his study how the genetic markers in humans are being used to infer the historical geographical distribution of humans and the dispersal of our ancestors. Explain how the genetic markers on our DNA (from blood samples) helps us understand that history. What are the techniques he is using? What is the nature of the evidence? What are the major conclusions about the journey of our ancestors out of Africa?What were the major migrations of humans to all the other continents? Approximately when did each migration occur and what were the major paths? How does the evidence support these conclusions? What Supporting evidence besides the DNA evidence is being used to support these conclusions?

5. Provide an adaptive and a non adaptive hypothesis for the evolutionary loss of useless organs, such as eyes in many cave-dwelling animals. How might these hypotheses be tested?

6. Directional selection is one of the models of natural selection. Describe this type of selection in terms of the frequencies of advantageous alleles over time. What is the trend over time? What is the eventual outcome for this allele as long as no other evolutionary factors intervene? Describe at least one good example of directional selection.

7. Consider the first copy of an allele for insecticide resistance that arises by mutation in a population of insects exposed to an insecticide. Is this mutation an adaptation? If, after some generations, we find that most of the population is resistant, is the resistance an adaptation? If we discover genetic variation for insecticide resistance in a population that has had no experience of insecticides, is that variation an adaptation? If an insect population is polymorphic for two alleles, each of which confers resistance against one of two pesticides that are alternately applied, is that variation an adaptation? Or is each of the two resistance traits an adaptation?Explain your reasoning thoroughly.

8. Suppose that a mutation in a species of annual plant increases allocation to chemical defenses against herbivores, but decreases production of flowers and seeds (i.e., there is an allocation trade-off). What would you have to measure in a field study in order to predict whether or not the frequency of the mutation will increase?

9. In many socially monogamous species of parrots and other birds, both sexes are brilliantly colored or highly ornamented. Is sexual selection likely to be responsible for the coloration and ornaments of both sexes? How can there be sexual selection in pair-bonding species with a 1:1 sex ratio, since every individual presumably obtains a mate? Which of the models of sexual selection described in the book might account for these species characteristics?

10. Kin selection explains why organisms may provide benefits to relatives. Is there a conflict between the principle of kin selection and the evolution of siblicide and abortion?

11.Many species of albatrosses and other seabirds nest in colonies on islands. The adult search for food at sea,sometimes over great distances. Some ecologists who study seabirds turn to their favorite topic of discussion in a bar one evening, and one says, âI can imagine an albatross genotype that destroys the eggs of nestlings of its colony mates when the parents are away foraging, and leaves them dead without eating them. Do you think such a behavior would evolve?â One of his companions says, âYes, because it would make more food available for the albatross and its offspring.â Another says, âNo, because it would threaten the survival of the population.â The fourth says, âYouâre both wrong. I have a different explanation for why albatrosses donât kill othersâ chicks.â What is the fourth ecologistâs explanation, and why does she think her companions are wrong?

12. The concept of a species is fundamental to understanding biology, yet there may not be one definition that fits all âtypesâ of organisms (e.g. animals, plants, fungi, bacteria, slime mold, lichens, etc.). Discuss several of the definitions of a species as presented in class and present your own definition for a species. Compare the strengths and weaknesses of each definition. Ernst Mayr is strong proponent of the biological species concept.How does he justify his position? Do you agree or disagree? If we employ the biological species concept, when did species first exist? What were organisms before then, if not species? What might the consequences of the emergence of species be for processes of adaptation and diversification? Be sure to explain your reasoning thoroughly.

13. The process of speciation ultimately involves the development of reproductive isolation between two related populations of organisms. Describe the various types of both prezygotic and postzygotic reproductive isolation and give an example of each.

14. Respond to the following quote from the character named Mr. Spock in âStar Trekâ:âA truly successful parasite is commensal, living in amity with its host, or even giving it positive advantages, as for instance, the protozoans who live in the digestive system of your termites and digest for them the wood they eat. A parasite that regularly and inevitably kills its host cannot survive long, in the evolutionary sense, unless it multiplies with tremendous rapidity ... it is not pro-survival.âFrom what you have learned in this course, do you agree or disagree with Spock? How can you apply your reasoning to the relative âfitnessâ of HIV which causes AIDS, the Ebola virus which causes hemorrhagic fever,fleas which suck blood from dogs, or the prokaryotic ancestors of mitochondria and chloroplasts?

15. In many species of birds and mammals, clutch size is larger in populations at high latitudes than in population sat low latitudes. Species of lizards and snakes at high latitudes often have smaller clutches, however, and are more frequently viviparous (bear live young rather than laying eggs), than low-latitude species. What selective factors might be responsible for these patterns? Explain your reasoning.

16. The popular media often presents evolution as being a predictable process with a definite goal. For instance, in one âStar Trek: Voyagerâ episode, the captain instructs the shipâs computer to extrapolate the âprobable courseâ of evolution of hadrosaurs (a bipedal dinosaur), if hadrosaurs had been removed from Earth before the Cretaceous-Tertiary (K-T) Extinction and allowed to evolve on another planet. What information about the hadrosaursâ new environment would have been useful in developing the best possible prediction? Given what you know on genetic drift and selective agents, is it possible to accurately predict the long-term course of evolution?

17. Young children often develop strong food preferences that sometimes seem bizarre to their parents --- such as wanting to eat only a certain food prepared in a familiar way, or being reluctant to each new foods or foods with strong or bitter tastes (like coffee and some vegetables). Develop an evolutionary explanation for such preferences. What evidence would you gather to investigate your hypothesis and rule out alternative explanations?

18. Many organisms, such as mammals, only reproduce by sexual means. Other organisms are exclusively asexual,such as many of the bacteria and fungi. And still others have ways of propagating by both sexual and asexualmeans. Discuss the relative advantages and disadvantages of each mode of reproduction. Why arenât all organisms sexual critters? Why are many asexual organisms still very successful as evidenced by the pure abundance and diversity? What is the adaptive significance of having different genders (e.g. male and female)?In other words, why sex?

19. How might differential expression and regulation by Hox genes contribute to mosaic evolution in which different segments of an animal body plan evolve different morphology?

20. Development of a morphological structure involves many different types of gene products, including transcription factors, signaling proteins, and âeffectorâ genes such as enzymes. When a morphological change occurs in a single mutational step, which of these types might be more or less likely to be involved? Within a gene, would such single-step events be more likely to involve coding or non-coding sequences, and what characteristics of the geneâs function might affect this likelihood?

21. Since 2001, the complete DNA sequences of the genomes of many people have been determined. If humans,along with other forms of life, have evolved from a common ancestor, what evidence of this would be expected in the human genome? In what ways might the history and processes of evolution help us interpret and make sense of the human genome sequence data?

22. Paleontologists and some biologists commonly infer function, and even behavior, from anatomical details.Skeletal features, for example, are often used to infer that an extinct mammal (such as an early hominid) was highly, somewhat, or not at all arboreal. This inference assumes a good fit of form to function (i.e., optimal form). Can this assumption be justified?

23. Stephen Jay Gould (1989) and others have argued that the evolution of self-conscious, intelligent species (i.e.humans) was historically contingent: it would not have occurred had any of a great many historical events been different. The philosopher Daniel Dennett (1995) and others have disagreed, arguing that convergent evolution is so common that if humans had not evolved, some other lineage would probably have given rise to a species with similar mental abilities. What do you think, and why? If Gouldâs position is right, what are its philosophical implications, if any?

24. Explain how Intelligent Design was determined as a religious view rather than a scientific view in the court casein Dover, PA. Should a scientific explanation of evolution be included in a science curriculum in K-12 schools?How is science and religion different in how they seek answers to questions? How is term "theory" used differently in science than in everyday English use? What is biological evolution? What evidence is used to support the scientific explanation of evolution? Is it possible to accept scientific explanations without rejecting religious faith?

25. Discuss how a creationist versus an evolutionary biologist might explain some human characteristics and the implications of their differences. Sample characteristics: eyes; wisdom teeth; individually unique friction ridges(fingerprints); five digits rather than some other number; susceptibility to infections; fever when infected;variation in sexual orientation; limited life span.

Case Study

Skolnikland is in Eastern Africa, with a population of 30 million people. The country has a plains region, a hill region, and a region with high mountains. It has a number of ecosystems. The plains are dry for much of the year, there is some rainforest, and the rest of the country includes both hills and mountains. There are two seasons of heavy rainfall.

The citizens come from several ethnic groups that tend to live in their own regions and speak different languages. The ethnic groups largely follow one of three different religions. The large cities are mixed ethnically. One ethnic group is economically and socially very dominant. The people from this group live in the capital and most of the large cities. The national language is the language of this dominant ethnic group.

According to World Bank criteria, Skolnikland is among the poorest countries in the world. The economy has been growing at about 4% per year on average over the last decade, but the economy had very slow economic growth in the decades prior to that. The richest 10% of the population controls 80% of the national income.

About 80% of the people live in rural areas and 20% in urban areas. The number of people living in urban areas has been growing recently at an increasing pace. Most people earn their livelihood in agriculture but there is an increasing garment manufacturing industry in the two largest cities. There are also a number of mining industries. In addition, other export industries are beginning to grow, mostly focused on the export of commodities to China.

The total fertility rate is about 4.5 but it has been declining slowly over the last two decades, from over 6. There is an almost equal number of men and women in the population. Infant mortality is about 90 per 1,000 live births. Maternal mortality is about 500 per 100,000 live births. Thirty-five percent of the children are underweight for age.

The adult literacy rate is about 40%. The educational enrollment rate, especially for girls at the primary and secondary levels, has been growing slowly, but steadily. Most recently, this rate has been growing at an increasing pace and about 75% of the girls now attend school regularly, although many of them are of very low quality.

Only about 50% of citizens have access to safe water. Only about 30% have access to sanitary disposal of human waste.

HIV prevalence is 7% of the adult population. The number of new HIV cases annually has begun to plateau. About half of the people eligible for treatment for HIV are on treatment. Malaria is rampant in the plains.

Investments in the road system have been growing at a solid pace in the last decade and the use of private automobiles has begun recently to increase more rapidly.

Skolnikland has a pluralistic health system that is made up of public and private institutions, publicly financed providers, licensed private providers, unlicensed medical practitioners, and traditional healers. There is no health insurance, except for some free services for the poor in the few publicly financed hospitals, which the better off people do not attend. The health system is not very effective or efficient and is generally of low quality. The HIV, TB, and malaria programs are not effective or efficient and they are just beginning to adopt paradigms for services that follow global best practices.

QUESTION 11

If you were interested in investing in maternal and child health using a results-based financing scheme, which program is the most appropriate?

A. Invest in training more skilled birth attendants in a village.

B. A plan to give the local clinic in the village a grant after the clinic demonstrates that its efforts have led after two years to lower under-5 child mortality.

C.Provide all pregnant women in the village with a full course of antenatal vitamins.

QUESTION 12

In Skolnikland today, approximately what proportion of the burden of disease, measured in DALYs, is likely to be Group I-related?

A. 45%

B. 35%

C. 60%

QUESTION 13

In Skolnikland, life expectancy fell in the 1990s, which can be attributed to:

A. Malaria

B. HIV

C. Pneumonia

QUESTION 14

In Skolnikland, the cost for treating severe diarrhea in young children is $18 for community-based care and $20 for clinic-based care. The cure rate for community-based care is 60%. The cure rate for clinic-based care is 90%. Which approach is the most cost-effective?

A. Community-based care

B. Clinic-based care

C. They are equally cost-effective

QUESTION 15

In Skolnikland, what are likely to be three of the five leading causes of death of under-5 children, besides perinatal causes?

A. TB, diarrhea, pneumonia

B. Malaria, diarrhea, measles

C. Diarrhea, malaria, pneumonia