Study Questions / Quiz Prep. (Consult Required Reading and lecture notes for answers.)

1. What are the three properties of the “Living State"? (this presentation page)
2. In order for the “Living State” to persist on a world, individuals must be able to reproduce. Why?
   
3. Your car is operationally complex and exhibits very complicated behavior. Why is your car not “alive”?
4. Evolution science is a synthesis of which two sciences? (myths of evolution)
5. Complete this line from the textbook, "The mechanism of natural selection is the simple... "
6. Complete this line from the textbook, "Stated more precisely, natural selection is... "
7. Natural selection is the product of what two conditions?
8. How is the "fitness" of an individual measured?
9. What is meant by the expression, "Selected for"?
10. What is meant by the expression, "Selected against"?
11. A Trait is any behavioral, morphological, or physiological feature of an organism. What two conditions make a "trait" an "adaptation".
12. What do adaptations, "represent"...?
13. Inherited traits ultimately are physical expressions of information held in the molecule, DNA. A stretch of DNA that codes for a given trait (by virtue of polypeptide sequencing) is called a ___________.
14. What are alleles?
15. Genes are organized into larger structures called chromosomes. Most multicellular organisms possess two copies of each type of chromosome. Where do each of these two chromosomes come from?
16. The "genotype" describes the statistical mix of alleles. What is a heterozygous mix?
17. The "genotype" describes the statistical mix of alleles. What is a homozygous mix?
18. Label the below drawing. Two alleles are present, A (dominant), a (recessive)

19. In the drawing above, the condition, AA, is homozygous or heterozygous? Produces which phenotype?
20. In the drawing above, the condition, Aa, is homozygous or heterozygous? Produces which phenotype?
21. In the drawing above, the condition, aa, is homozygous or heterozygous? Produces which phenotype?
22. How is the condition of "codominance" different from the condition of "dominance and recessiveness?"
23. The example below shows five different color phenotypes. But the previous example only had two phenotypes. What are the two reasons this one has five phenotypes?

24. What is "allele frequency?"
25. What is "genotype frequency?"
26. Based on the results of the Grant team’s investigations of Galapagos finches, did individual finches adapt to their environment?
27. Based on the results of the Grant team’s investigations of Galapagos finches, did a new species of finch arise that was more tolerant to their environment?
28. Based on the results of the Grant team’s investigations of Galapagos finches, did the finches develop new, special adaptations that enabled them to better cope with drought?
29. Based on the results of the Grant team’s investigations of Galapagos finches, did genes that influenced beak size change from generation-to-generation, depending on environmental conditions?
30. A comparison of the distribution of beak sizes for Daphne Major finches for 1976 and 1978 (figure 5.9) indicates which of the three types of selection (figure 5.10)?
31. What is a "mutation?" What is the significance of mutations in terms of genetic variety in a population?
32. What is "genetic drift?" What is the significance of genetic drift in terms of genetic variety in a population?
33. What is "gene flow?" What is the significance of gene flow in terms of genetic variety in a population?
34. Trade-offs. Under one set of environmental conditions, a set of traits maximizes the fitness of an individual. How might this set of traits affect the fitness of this individual under different environmental conditions?
35. Given the concept of trade-offs and changing environmental conditions, why can there not be "one best design?"
36. The frequency distribution of beak depths is shown in figure 5.15 for the three most abundant finches on Santa Cruz Island in the Galapagos. What is the relationship between bill depth and seed size (shown in error as Seed "depth")?
37. What is the nature of trade-offs associated with these three bill depths and the available food supply?
38. List the myths of evolution? (from lecture and (myths of evolution presentation)
39. Using modern evolution theory, which picture most reasonably predicts what humans will look like 10,000 years from now? Briefly explain.

40. Imagine a scenario in which continuous generations of chimpanzees are placed in front of typewriters for their entire lives. Using the modern theory of evolution, and given all the remaining time until the end of the Universe, what are the chances that the chimpanzees would produce a single meaningful sentence? Briefly explain.

41. Below are pictures that represent a single species of beetle. The pictures represent genetic snapshots of the beetle population at different critical times. Using modern evolution theory, interpret these pictures and the action?

Scenario 1.

			Reproductive Event
Population at the start of a new generation		Surviving adults just prior to reproductive event		Population after reproductive event
Time ->

Scenario 2.

			Reproductive Event
Population at the start of a new generation		Surviving adults just prior to reproductive event		Population after reproductive event
Time ->

Scenario 3.

			Reproductive Event
Population at the start of a new generation		Surviving adults just prior to reproductive event		Population after reproductive event
Time ->

Synthesis (These are not official study questions. But you should try to answer them on your own.)

Presentation

Living State

I propose that the Living State is expressed by physical objects that have the following characteristics:

1. Complex operational systems -- systems whose operations produce some recognizable, rewarding outcome.
2. Self-maintaining -- resulting in some rewarding operational level. There are automatic controls in place that monitor, adjust and repair systems in rewarding ways.
3. Exploitive -- of available environments. Providing rewarding support of the self-maintenance component. Exploiting resources and opportunities.

Image source: Tom Morris

The image above is a game-style Heads Up Display (HUD) for a little salamander (represented as the little yellow creature at bottom center). This image illustrates the high level of connectedness that a living individual has with its surrounding environment. In the process of trying to maintain the living state, this salamander receives many rewarding services from a variety of internal systems. Note that this is just a snapshot of the instantaneous situation. In another millisecond, the situation could change in important ways. At this time, the salamander is consuming services for remote environmental characterization. For example, eyes sample and focus light reflected from surrounding objects (photoreception). The nose samples chemicals in the air and the tongue samples chemicals in the water (chemoreception). Ears report patterns of vibrations in the air made by surrounding objects in the environment (mechanoreception). And heat sensors in the skin report the thermal environment in the water and out (thermoreception). The salamander's brain (small you may think) integrates sensory services and passes results to a decision structure with command authority. It tracks opportunities (the ladybug) and threats (the flying gull and the standing great blue heron). The decision to exploit or retreat is a significant one -- it could produce rewards or failures. Added to the mix is a consideration of the salamander's internal state. Certain internal reserves are approaching critically low levels, and any increased activity to replenish them speeds their depletion further. Besides, this little salamander isn't operating at one-hundred percent. He has sustained injuries to his right ear and tail. He's got parasites and a kidney infection. Despite that this little salamander has been successful so far in his/her life, it's still not sexually mature. Right now, its primary mission is to maintain the living state. If it reaches a state of sexual maturity intact, it may or may not contribute genetic information into the next generation of salamanders in this area. This scenario attempts to illustrate the dynamical and extremely complex nature of the living experience. If you set two slightly different salamanders side-by-side in this scenario, it would be impossible for anyone to argue which of the two has the most promising mix of features. Because of this naturally dynamical system, the ability to predict outcomes is very limited -- like trying to predict the weather a week from today. As a result, evolution is a "phenomenal" system, not a logical system. The system of genetics and life is not constrained by human logic, but instead it is constrained only by the physical limits of the systems in play.

Evolution

The change in the genetic makeup of a population from one generation to the next.

Here is an extremely simplified example:

Generation 1	Generation 1	Reproductive Event	Generation 2
75% speckled 25% striped	100% speckled 0% striped	New individuals receive genes exclusively from surviving adults.	100% speckled 0% striped
Population at the start of a new generation. In this example, color pattern is controlled by two kinds of genes: 1) speckled 2) striped	Surviving adults just prior to reproductive event. Note that new individuals cannot immediately pass their genes to a new generation. They must develop sexual maturity. This takes time. In the meantime, they try to stay alive.		Population after reproductive event. The mix of genes in this generation is different from the mix of genes in the pervious generation. This observed difference is an evolutionary result.
Time ->

Since the genetic makeup of the second generation (100% : 0%) is different from the genetic makeup of the first generation (75% : 25%), this is an evolutionary result.

Natural Selection

Differential, non-random success (survival to sexual maturity and reproduction) within a population.

Dependent upon:

1. Genetic Variety

2. That genetic variety results in differences between individuals in the way they interact with their environment.

Natural selection is an ECOLOGICAL phenomenon.

If an evolutionary result follows occurrences of natural selection, then we have "evolution by natural selection."

Since the phenomenon of natural selection is the environment acting in non-random ways on a population's genetic variety, natural selection has the potential to shift the proportions of genes (alleles) in the population. When the environment changes, then natural selection could shift the proportions of genes (alleles) in a different direction.

Fitness (a numbers game)

Fitness in the Individual: proportionate contribution of its genes into future generations.

• High fitness in the individual: Live to sexual maturity. Mate frequently and/or produce many offspring.

• Low fitness in the individual: Die before reaching sexual maturity. Producing no offspring.

Fitness in alleles: Proportion of alleles for a given trait in the population.

High fitness for an allele: Makes up 75% of all alleles present in the population for the trait.

Low fitness for an allele: Makes up 5% of all alleles present in the population for the trait.

Adaptation - that is, EVOLUTIONARY adaptation

Any heritable trait that:

1. maintains or increases fitness of an organism.

2. has developed as a result of evolution-by-natural-selection.

The difference between EVOLUTIONARY adaptation and PHYSIOLOGICAL adaptation

An evolutionary adaptation is a trait in an individual that is inherited from the individual's parents (through inherited genes). An evolutionary adaptation could be a structure as simple as a beak or it could be a complex system like an eye or the circulatory system.

Evolutionary adaptations are NOT a response to the environment, but a consequence of the environment (through many generations of evolution-by-natural selection).

A physiological adaptation is an instantaneous change in the OPERATION of the body. Although, we think of your circulatory system as an evolutionary adaptation, its moment-to-moment operation is physiological. So, if you walk up three flights of stairs, your heart starts pumping faster and your blood pressure increases. This change is a physiological adaptation -- an operational adaptation.

Physiological adaptations ARE responses to the environment -- but only in the way that on-board systems are operated.

Physiological adaptations themselves or their outcomes cannot be inherited or passed on to offspring (despite Lamarck). But the information that is used to build and operate the system IS inherited and CAN be passed on.

For example, we think of the eye is an evolutionary adaptation. But its operations are physiological adaptations.

Source: By Rhcastilhos [Public domain], via Wikimedia Commons	Source: By Rick (Owner) [CC0], via Wikimedia Commons	Source: By Rick (Owner) [CC0], via Wikimedia Commons (with modifications)
Evolutionary adaptation. The physical manifestation of the eye is an evolutionary adaptation.	The operation of the eye is a physiological adaptation. In bright light, the eye's iris has closed the aperture of the eye to a small opening. This is a physiological adaptation to bright light conditions.	The operation of the eye is a physiological adaptation. In dim light, the eye's iris has expanded the aperture of the eye to a large opening. This is a physiological adaptation to dim light conditions.

Gene

A section of DNA that codes for a given trait
(the simplest definition -- actually, it is more complicated)

Image source: Wkipedia.com

Image source: Pearson Education

Allele

Alternate forms of genes in the population that code for the same trait.

For example, All of the genes below reside at the same address on the chromosome (locus), are slightly different from each other, and code for the same trait -- but in different ways. If their target trait is flower color, for example, then they are alleles for flower color.

This gene codes for flower color. It makes flowers blue. This gene is one of three alternative forms of flower color genes in the population -- one of three alleles for flower color.	This gene codes for flower color. It makes flowers red. This gene is one of three alternative forms of flower color genes in the population -- one of three alleles for flower color.	This gene codes for flower color. It makes flowers green. This gene is one of three alternative forms of flower color genes in the population -- one of three alleles for flower color.

Genotypes, Phenotypes, Dominance, Recessiveness, Codominance

Image source: Pearson Education

The more loci, the greater the variety

Image source: Pearson Education

Peter and Rosemary Grant and the Ongoing Evolution of Galapagos Finches

Image source: Pearson Education (with modifications)

Image source: Pearson Education (with modifications)

Modes of Natural Selection

Image source: Pearson Education

Random Changes in a Population's Genetic Makeup

Mutation

Image source: Wikipedia.com

Genetic Drift - Random Walks

Image source: Wikipedia.com

Migration / Gene Flow

Image source: wikipedia.com

Adaptations and Trade-offs

Image source: Pearson Education (with modifications)

Examples of Trade-offs.

Links for Enrichment and Further Learning

Evolution/Creation Links

Index to Creationist Claims
Icons of Evolution FAQs
Nat Ctr for Science Ed
Well-balanced Wikipedia article on Intelligent Design

What About Intelligent Design?

Watch this special NOVA production that reveals the scientific shortcomings of the concept of "Intelligent Design."

What About God?

To see how some Christian college students are dealing with faith and science, watch this episode of the NOVA series on evolution.

Understanding Evolution
New Scientist magazine's Myths and Misconceptions about Evolution
Genetic Algorithms and Evolutionary Computation
PBS Evolution Library
Darwin Awards

Books

The Reluctant Mr. Darwin, by David Quammen
Intelligent Thought, by John Brockman (ed.)
Why Darwin Matters, by Michaael Shermer

Just for Fun...

Evolutionists flock to Darwin-shaped wall stain. Source: The Onion, Sept. 5, 2008.