all relevant constants..grant/courses/bio161/exams/ex3f… · _____ (f) on the islands where these...

BIOLOGY 161 – EXAM 3 page 1

#1. Please briefly describe the two principal objectives of population ecology. (a) objective #1 – 2 pts (b) objective #2 – 2 pts

#2. Please offer a brief but concise definition of Evolution. 2 pts

#3. Please offer a brief but concise explanation of how Evolution can occur by Natural Selection(hint: there three specific steps).1 –2 –3 – 3 pts

#4. Besides Natural Selection, there are at least three other major causes of evolution. Please list and briefly define each one.

1 – 2 – 3 – 3 pts

#5. According to the CIA Word Fact Book (http://www.cia.gov), the US population birth rate is 14.18 births/1,000 people, the death rate is 8.27 deaths/1,000 people, and the net migration rate is +2.92net immigrants/1000 people (as of July 2008). If the US population is about 304 million now (2008), what will be the size of the US population next year?

Please set up the equation one would use to calculate the US population for next year (2008), but YOU DO NOT NEED TO FIND THE MATHEMATICAL ANSWER – JUST SET UP THE PROBLEM CORRECTLY AND PLUG IN THE CORRECT NUMBERS WHERE THEY BELONG.

6 pts

#6. This question will assess your understanding of how to code the above model in EXCEL. In the box below, please enter the exact code that would successfully simulate the US population size next year (see birth, death, and migration rates from above):

#7. According to the CIA, the birth rate for Afghanistan is more than 45 births/1000, which is more than twice the global birth rate. Please examine the age structure diagram at right and explain HOW DO THESE DATA offer an explanation for this high birth rate per 1000 people in Afghanistan? Why does such a high birth rate result from THIS pattern of age structure?

2 pts.

#8. Please briefly define “survivorship.”2 pts.

#9. At right are three curves A, B, and C. Which one cannot be a survivorship curve and WHY?

2 pts.

B3 =

3 pts

BIOLOGY 161 – EXAM 3, 12 December 2008 page 2

#10. What is the major reason why the exponential model of population growth is not a very good model for population growth rate?

2 pts

#11. At right is a plot of clutch size (# eggs/ nest) versus female density for song sparrows. What is the evidence in these data for density dependent population regulation?

3 pts.

#12. Consider the model for single species population growth at right. Explain in words what is the main prediction of this model?

2 pts

#13. Draw a little graph below showing the population size vs. time beginning with an initially large (N >> K) and with an initially small (N

BIOLOGY 161 – EXAM 1, page 3 Name ___________________________________________ (+1 pt)

#16. More questions on Caribbean and Venezuelan Guppy Evolution in general.Circle the one answer that best reflects how an evolutionary biologist would answer. { removed due to copyright }

#17. The figure at right shows the distributions of head sizes for two species of cave salamanders in three different caves in the southwest USA. Species A lives alone in Crystal Cave. Species B lives alone in Dark Cave. They co-occur in Bat Cave. Head size relates to prey item size.

Please explain how the phenomenon of “Competitive Character Displacement” could account for the coevolution of differences in head size distributions among species and caves. How might this have evolved by evolution by natural selection? Could this be coevolution?

5 pts

#18. Jean Baptiste Pierre de Lamarck (at right) had a very different hypothesis than Darwin’s concept of natural selection for the evolution of characteristics such as depicted above. Briefly, how would Lamarck have explained the causes of evolution above and why EXACTLY is Lamarck wrong?

3 pts.

#19. This question will assess your understanding of the "intermediate disturbance hypothesis" for the maintenance of local species diversity that was proposed by Sousa to account for variation intertidal algae and animal diversity on rocks and boulders of various sizes.

(a) On the axes at right plot the relationship between disturbance and diversity according to the "intermediate disturbance hypothesis."

Please, LABEL THE AXES!

3 pts(b) According to the "intermediate disturbance hypothesis," why is diversity low at very LOW levels of

disturbance? 1 pt

(c) According to the "intermediate disturbance hypothesis," why is diversity low at very HIGH levels of disturbance?

1 pt(d) According to the "intermediate disturbance hypothesis," why is diversity HIGHEST at

INTERMEDIATE levels of disturbance? 2 pts

+2 pts each

Species A Species B

Species A

Species B

CrystalCave

BatCave

DarkCave

head width (mm)

A B


#20. Working in the intertidal in Maine, Jane Lubchenco observed that tide pools tended to have either high density of green (G, Enteromorpha) or red (R, Chondrus) algae. She suspected that grazing by a common but patchily distributed algae eating snail (Littorina) was the cause.

She experimentally manipulated the density of snails in replicate tide pools (away from the crashing surf), and observed the effects of snail abundance on algal density and algal community composition.

Please summarize what she found in the figure at right. What was her explanation of this pattern? (hint: recall which algae is preferred food for the snails? can you figure it out from the figure? G = green algae dominant, R = red algae dominant).

5 pts#21. According to Lubcenco, predators can act in the same way on community diversity as do physical

disturbances that was proposed by Sousa (see Q #19). Please briefly explain this finding. 3 pts

PART 2

#1. Please briefly describe the two principal objectives of COMMUNITY ECOLOGY. Please use sketches from class to illustrate your explanation.(a) objective #1 – 2 pts(b) objective #2 – 2 pts

#2. Please offer a brief but concise definition of Coevolution.3 pts.

#3. Consider the simple two species COMPETITION model at right. On the axes below, please sketch the relationship

between the per capita growth rate of species 1 and the population size of species 2 that this model assumes.

#4. Without using any math symbols or notation, explain what is the main prediction of this model?

2 pts

N2

On the axes below, please sketch a typical plot of N1 and N2 numbers versus time that this model predicts.

N1and

N2

time

4 pts

Gonly

Ronly

G & Rpresent

# sp.


#1. Consider the simple two species PREDATOR * PREY interaction model.

On the axes below, please sketch the relationship between the per capita growth rate of PREY and the PREDATOR population size that this model assumes.

#2. On the axes below, please sketch the a typical plot of PREY and PREDATOR numbers versus time that this model predicts.

#3. Without using any math symbols or notation, explain in words what is the main prediction of this predator-prey model?

2 pts

#4. In the boxes below, write down the exact code for the entries in cells B3 and C3, respectively, that one would use to simulate the predator-prey equations above in MS-EXCEL.

Predators

On the axes below, please sketch the relationship between the per capita growth rate of PREDATORS and the PREY population size that this model assumes.

Preyand

Pred’s

time

4 pts

Prey

2 pts

2 pts


#5. The figure at right shows the distributions of beak sizes for two species of finches on four different Galapagos Islands (on the top two they co-occur, and on the bottom two, they are alone).

These data suggest that “Competitive Character Displacement” has occurred by coevolution.

If this hypothesis is correct, which of the following statements are likely to be TRUE and which FALSE?

Please write TRUE or FALSE on the line next to each statement.

_______ (a) Migration rate is high among these islands.

_______ (b) There must be a genetic basis to beak depth in both species.

_______ (c) When a migrant G. fortis from Daphne arrives on Pinta, likely the migrant will have to grow a larger beak rapidly or it will starve.

_______ (d) On every island there is a wide range of seed sizes available and the different sized beaks (small or large) are best at eating the corresponding size of seed (small or large).

_______ (e) On the islands where these 2 species co-occur, birds with intermediate beak depths (about 10mm) are likely to find less food due to competition and these finches will produce fewer offspring.

_______ (f) On the islands where these 2 species co-occur, the small beaked G. fortis all migrate to Daphne where they can flourish.

_______ (g) On the islands where these 2 species co-occur, birds with the intermediate beak size interbreed and thereby leave fewer offspring – and that’s why they are so rare.

_______ (h) The favorite species of seeds that G. fuliginosa eat on Los Hermanos happen to be smaller on the islands where the finch species co-occur, and that’s why their beaks are smaller there – G. fuliginosa beaks are simply tracking the changes in the seed size of their preferred food supply.

_______ (i) According to Chapter 1 of the Beak of the Finch, understanding the pattern of character displacement in the figure above was the principal reason why Peter and Rosemary Grant decided to devote their research careers to the Galapagos Islands “Darwin’s Finches”.

max 10

G. fortis

G. fuliginosa


#6. More Questions on the Galapagos Finches: Scientists have long believed that the 14 species of finches on the Galapagos Islands evolved from a single species of finch that migrated to the islands one to five million years ago. Today, different species live on different islands, and one of the major changes in the finches is in their beak sizes and shapes, as shown in the figure on the previous page.

Circle the one answer that best reflects how an evolutionary biologist would answer.

{removed due to copyright}

#7. At right is a diagram of the research results by Robert Paine on causes of species diversity in the intertidal in the Pacific northwest.

Please explain the results. (3 pts)

#8. One of the most important lab studies of predator prey dynamics was Huffaker’s (1957) study of predator and prey mites living in trays of rotting oranges.

WHY exactly did the predators coexist with their prey (as opposed to hunting their prey to extinction), and what are the general conclusions we can draw from Huffaker’s research?

(4 pts)

#9. Below is a cartoon entitled “Evolution Made Simple” from a popular magazine:

{removed due to copyright}

#10. (a). Please use a diagram and briefly explain what is the greenhouse effect? 5 ptsb). What are four of the principal greenhouse gasses? 2 pts

1 – 2 – 3 – 4 – (c). Current models predict that +2-5oC warming is likely by 2050 if our global society continues

with “business as usual” and atmospheric CO2 concentration is allowed to double. Please list at least three of the principal predictions for what is likely if global warming on this magnitude were to occur. 3 pts

+2 pts each

0

5

10

15

20

25

1962 1964 1966 1968 1970 1972 1974

with Pisaster

Pisaster removed


Please Read This Comment: You are welcome to download some or all of the material I have posted at this site for your use in your biology course. This does not include commercial uses for profit. If you do use any lengthy excerpts (more than 2 lines) of the material above, I request that you formally acknowledge this site and/or sites I have acknowledged as the source(s). I also request that you reciprocate and send me a copy of your biologymaterials so that I may see what you have put together. Please send comments to me: bwgrant@ widener.edu. Copyright - Bruce W. Grant, 2008.

#11. According to archeologist Gary Rollefson, the dramatic abandonment of the Neolithic settlements such as the ‘Ain Ghazal at 6000 years ago was due to anthropogenic degradation of the fragile Jordan Valley ecosystem.

Imagine yourself as one of the members of this community at about 6100 years ago, just prior to its abandonment. What were the major environmental signposts that the ‘Ain Ghazal culture and way of life were nearing a collapse?

5 ptsPlease list 5 major global environmental signposts that our “modern” culture and way of life are not sustainable. (note: precision is not expected for any numbers you give)

5 pts

#12. This question will test your understanding of ecological economics. Below is a sketch of the relationships between “natural capital,” “human capital,” and “human-generated waste” that wasused in class to describe the presently unsustainable economic system (referred to as the “Neolithic” model).

(a). What is “Natural Capital”?

2 pts

(b). What assumption about the supply of “Natural Capital” does this model make? 1 pt(c). What assumption about “Waste” disposal does this model make? 1 pt

(d). Briefly explain the basic changes to the above economic model that are necessary to engineer a “sustainable” (Post-Neolithic) economic model.

4 pts(e). Herman E. Daly, an internationally recognized economist, once wrote that "There is something

fundamentally wrong in treating the earth as if it were a business in liquidation..." Please briefly explain what he meant by this comment. Exactly what is being liquidated?

2 pts

Natural Capital Human Capital Waste+technology

away

all relevant constants..grant/courses/bio161/exams/ex3f… · _____ (f) on the islands where these...

Documents