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=MGED 3040 Final Project: A Review of Darwin's "On the Origin of Species"=

===Individually, you will be assigned a chapter from Charles Darwin's Original manuscript of "On the Origin of Species" available free online at: @http://www.gutenberg.org/files/1228/1228-h/1228-h.htm===

For your assigned chapter you will be required to:
 * 1) Summarize Darwin's thoughts and theories related to the assigned chapter with respect to the overall theory of evolution. This should be at minimum 3/4 of a page (single spaced) 1" margins.
 * 2) Key scientific principle(s) that a science teacher could utilize to explain the "theory of evolution"

Chapter 1: Variation Under Domestication: John Owens

In this chapter Darwin is focused on the variation of species and subspecies, more specifically those that are domesticated. As Darwin notes throughout this chapter, we find that species of both plants and animals show greater signs of variation than similar parent species found in nature. One of the main points he makes early in the chapter is the differences in exposure animals and plants undergo in domestication versus nature. Domesticated species undergo conditions vastly different than those experienced by species found in their natural setting, such as less uniformity. Darwin also poses the thought that the causes of variability might come before conception. He states that many theorists have debated when variability actually occurs whether it is before conception or at some stage during embryonic development. Through his studies, including a study of pigeons, Darwin believes that the variability of domesticated species is not the result of a large number of ancestor species but rather the process of selection by man. In domesticated species, man will methodically and unconsciously select features that are useful or pleasing, and then select those individuals for breeding. Traits which are useful or pleasing can vary from one region to the next, and as a trait is noticed, the man might actively attempt to breed more of a species that shows a certain characteristic. The principle Darwin ascribes to this is that of, “unconscious selection”, we see a characteristic that catches our eye and we try to isolate and propagate more individuals with that specific trait. As such domesticated breeding continues to increase a large variety in a given species. Much like the pigeon, there are several different subspecies but they can all be traced back to one ancestor species, the Rock Pigeon. **Principles for Teaching:** One of the main principles that could be used here is the theory of natural selection. Natural Selection could be introduced and discussed as it pertains to domestication and Darwin’s theory of “unconscious selection”. A lesson could be done on the similarities and differences in selection between species in nature and in domestication.

Chapter 2: Variation Under Nature: Brittany Herbert Variability is defined as having individual differences with widely ranging species. Darwin defines the term “species” as “the known element of a distinct act of creation”. He then defines “variation” as “modifications directly due to the physical conditions of life” and “not inherited”. Offspring from the same parents can have individual differences because each individual is born with differences that allow natural selection to accumulate. Forms of individuals that resemble a species so closely could be linked in that distinct species but are not because naturalists want to have “good and true species”. If a form happens to be ranked as a species it will be done by a group of naturalists who can consider the geographical distribution, analogical variation, hybridism, etc. Darwin states, “Close investigation, in most cases, will bring naturalists to an agreement on how to rank doubtful forms”. He looks at slight individual differences as of high importance just as he would look at varieties that are more distinct because these are due to the passage from one stage of difference to another in a long-continued action or physical condition. Not all varieties or initial species will immediately attain the rank of species. They may remain at an initial state or they may remain a variety for long periods of time. Darwin reveals that from his previous remarks, uses the term “species” for the sake of convenience to describe individuals that resemble each other.

Darwin describes how if a plant that inhabits a country were divided into two equal masses, one with the larger genus on one side and those with the smaller genus on the other side. He reveals that the genus with the larger number will have a larger number of the very common and dominant species. He contributes this to the fact that many species of plants inhabiting a country show that there is “something in the organic or inorganic conditions of that country favorable to the genus”. From looking at species as strongly marked and well defined, Darwin found that species in the larger genus would present varieties more frequently than the species of the smaller genus. He uses large trees as an example and the fact that where many large trees grow, you will expect to find saplings.

Darwin notes another point on varieties. He found that they generally have restricted ranges the same general characters as species. They can be distinguished from species by the discovery of intermediate linking forms and by the amount of difference. If a genus has more than the average number of species in any country, then he believes the species of these genus will have more than the average number of varieties. In most flourishing and dominant species, the larger genuses vary most and the varieties tend to convert in a new and distinct species. This results in the larger genus becoming larger and more dominant by leaving modified and dominant descendants.

This chapter could be used to teach students a key principle about variation: the fact that one species can be found in many different forms based on where they are located and their environment. This could be related to Darwin's observations of the Finches and how Finches found in different areas had varying beak sizes.

There are several key concepts that Darwin (1859) is introducing in Chapter 3, “Struggle for Existence.” Darwin (1859) defines “the term Struggle for Existence in a large and metaphorical sense, including dependence of one being on another, and including (which is more important) not only the life of the individual, but success in leaving progeny.” This leads us to an important concept of Natural Selection which Darwin(1859) introduces. The variability within a species is part of Natural Selection. Those individuals that include variations that are profitable to an individual or species will be successful and pass those traits to their offspring is the principle of Natural Selection. These variables are referred to as adaptations. These adaptations are influenced by several relationships including population, climate, competition, and dependency between organisms.
 * Chapter 3: Struggle for Existence**: Carole Amason

Although not clearly stated in this chapter, Darwin (1859) includes the concept of populations, but he is at the beginning stages in developing the concepts of today. Darwin’s(1859) vocabulary includes: geometrical ratio, distribution, rarity, abundance, extinction, and variation. These factors are part of the overall success or failure of species survival.

Climate is also a factor in the success or failure of species. Depending on the trends of weather patterns drought and temperature extremes can have dramatic affects on various species. Darwin (1859) comments “climate chiefly acts in reducing food, it brings on the most severe struggle between the individuals, whether of the same or of distinct species, which subsist on the same kind of food.” He goes on to say that if any species or individual does well during these climate changes that particular population will grow. Climate has a direct relationship with a species Struggle for Existence. When a species is growing the term he introduces is that the species is favored.

Competition and dependency between organisms are related and are complex checks between species. Competition between species including predator-prey relationships along with the availability of food also bear on its Struggle for Existence. Darwin (1859) uses an example of how cattle have a direct effect on the Scotch fir population in Staffordshire. He discovered through observation the cattle “browsed down” the seedlings so that they were not successful in growing, but where the cattle were not allowed to go the Scotch firs were successful in growth. These relationships are part of unexpected connections between species which Darwin (1859) refers to as a “web of complex relations.” The one relationship Darwin (1859) defines as the most severe is the one between individual of the same species. This is because they are in direct competition for food and their habits are the same. This relationship between individuals of the same species is important to their survival or lack of survival. Any advantage an individual has over another can increase its chances to survive. Darwin closes Chapter 3 with this quote, “When we reflect on this struggle, we may console ourselves with the full belief, that the war of nature is not incessant, that no fear is felt, that death is generally prompt, and that the vigorous, the healthy, and the happy survive and multiply.”


 * Chapter 3 Struggle for Existence: Implications for Teaching:**


 * Natural Selection** is a very important concept in Evolution. **Adaptations** of individuals within a population are key to the process of survival.
 * Populations** of species are directly related to survival, understanding how populations grow and decline can help to predict whether or not species continue or become extinct. Today four patterns of population growth are recognized; they are as follows: 1. Exponential growth: a population increase by a constant proportion, 2, Logistic Growth: populations reach a stable size that changes little over time, 3. Fluctuations, 4. Population Cycles. Along with population of species today we recognize the carrying capacity of populations. Factors recognized as influencing a population include birth, immigration, death, and emigration.
 * Climate** is also recognized as a important factor in a species Struggle for Existence. Changes in climate can result in favorable adaptations or extinction. Organisms that survive climate changes are the ones that have qualities that are favorable or adaptable to the environment.
 * Competition** and **dependency** within a species and between species are relevant factors in the success of all organisms. There are many factors that need to be taken into account when observing the natural world. Giving students real life examples will help students to understand the dependency and connections that are present.

All these factors listed above are important in understanding the theory of Evolution. Adaptations of species with regard to populations need to be clearly defined for students. Because these concepts have become more developed since this book was written current theories need to be presented to students. Darwin was at the beginning of observing these concepts and developing theories, so they are not as fully developed as science understands them today.

Chapter 4: Natural Selection (up to Circumstances Favorable): Jocelyn Vaughn Chapter 4: Natural Selection (rest of the chapter): Fred Barber Chapter 4-b. Natural Selection. Fred Barber III Darwin is describing in this part of the chapter his observations of circumstances favorable to natural selection. Darwin writes that natural selection works over a long period of time. Natural selection is determined by the rate of one species can reproduce in a environment and compete with a range of competitor species for survival instead of extinction. In the chapter, Darwin explains natural selection is involved in breeding. The studies of dominant trait are to be passed to one generation to the next and inferior traits should be eliminated. He also notes that in-breeding occurs when species are limited to little migration. An example of birds traveling from long distances shows that over a greater distance allows for more opportunity to breed with greater number because of the distanced traveled. Another example given in the chapter is one of a nurseryman, who selects only the seed for a crop that possesses the dominant trait for maximum growth and yield, rather than picking a variety of less quality. Isolation, in natural selection, viewed how Darwin observed organisms and how they adapted to their physical environmental changes. Darwin noted that organisms in small areas are less favorable to create new species and larger areas are more rapid in producing new species. He observed that species that have opportunities to travel over long distances, have the chance to pass on dominant traits and combine with like characteristic species. He also tells of the observation that the earth has more salt water and land mass than what is present of fresh water sources. Favorable circumstances and environment are among species living in larger areas equals favorable conditions to breed and compete for survival. On the other hand, species confined to isolation, runs to chance the breeding with same traits and no new traits to be introduced. This is again stressed that the results will only be determined over long periods of time. Then Darwin speaks of extinction of different species and what may affect the demise of a species. Species with the greater number and best environment will have the best chance of reproducing more rapidly. Species of smaller number, special/rare traits, and isolation contribute to less reproducing offspring. The species that can continuously exist in variable environments, reproduce in high rates, and out competes others will be in the dominant numbers. Thus, leaving the smaller/rare species to be out numbered and possibly go into extinction this way. The next part of the chapter presented several examples of plants and animals and how the ones that best fit to the conditions given thrived and survived. This was an example of geographic distribution and how species that adapt to the environment and compete to survive will out be dominant species. This will take many years to have a relative key to the changes that happen during the process of natural selection. Keys to Science Teachers: · Dominant/ Recessive Traits · Adaption of environment to species · Migration of species · Geographical distribution · Reproduction of Different Species and Condition Favorable/Unfavorable · Ecology/Geology needed for species

Chapter 5: Laws of Variation (through use and disuse): Kassidy Jacobs

Darwin believed that external conditions in life such as food, climate, etc. did have some effect on the modifications of organisms. He also believed that habits of an organism produced differences, and using these strengthened those differences while disusing them weakened the difference or actually completely diminished that organ. He also believed that the use or disuse had a heftier weight on their effects than did external conditions. Changes of structure at an organism’s early age will generally affect parts almost developed. Darwin also believed that there were many other correlations of growth, and that those correlations we are just simply unable to understand. He also believed that multiple parts of organisms varied in number and in structure, and that this could have been due to the simplicity that these were not specialized to any particular function, or use. That would then mean that their modifications were not closely checked by natural selection. Darwin then gathered that perhaps this is why some beings low on the scale of nature are more apt to vary than those beings who have their whole organization more specialized, and are ranked higher on the scale of nature. Darwin also believed that Specific characters, or characters that have come to differ since many species of the same genus branched from a common parent, are more likely to vary than generic characters, or those characters which have long been inherited and have not varied within this same period. Darwin stated that he had very little doubt that use in our domestic animals strengthened and enlarged certain parts, while not using them weakened or even diminished these parts. He believed that these types of modifications were inherited. Under the idea of free nature, the concept that we can have no standard of comparison to judge the effects of long-continued use or disuse and where we do not know the parent-forms, that still many animals contain structures that can still be explained by the effects of disuse. An example Darwin gave of use or disuse involved the Ostrich. As thought that the early creations of ostrich had habits much like those of the bustard. As natural selection increased in successive generations of the first ostrich, the size and weight of its body varied, its legs were used more, the wings used less, and this then resulted in the ostrich’s incapability to fly, due to the disuse of its wings. In theory, whatever the cause may be of each slight variation in offspring from their parents, it is the steady accumulation through natural selection of such variations that are beneficial to the organism, that gives rise to all the more important modifications of structure, that the many beings on earth are able to struggle amongst one another, in which the best at adaptation are able to survive. In implications for teaching variations of structures among organisms of the same offspring i s in essence exactly how evolution is taught. In expounding upon the theory of use and disuse and how these variations occur, whether it be the process of natural selection, use or disuse, or the external conditions of climate and food, variation can be acknowledged as a change due to how the organism is adapting to its environment. The idea of use or disuse simply states that if a structure is not used, it will weaken or diminish, which in turn creates a modification to that being. I would want students to understand that the idea of evolution is not “what did we evolve from” but rather why did these modifications occur to the original structure of organisms, or specifically man.

Chapter 6: Difficulties on Theory (through organs of little importance): Melodie Floyd

Melodie Lane Floyd MGED 4030-Final Exam Difficulties on Theory 12-10-2010

6. DIFFICULTIES ON THEORY In chapter six, Difficulties on Theory with respect to his theory of evolution, Charles Darwin had many variables in how transitions between generations could be explained for the process of natural selection. Variables he refers to as “Variables of Descent with Modification”. He describes these variables as; The transition of a species from one generation to the next” (Darwin), the individual transition of the species, how the transitions have the means to make the transformation or to exclude the transformation, how rare the transformation may be, the habits of the species and their diversity, as well as the ability for a species organs to be perfect or imperfect. Charles Darwin states; “Difficulties so grave-I can never reflect without being staggered.”(Charles Darwin) He wondered why we could not see transformations, how habits of one species would differ from a species that it transformed with different habits. “Instincts, sterility, modifications, habits and organ development” (Darwin) are all difficult to explain. When speaking on the absence or rarity of transactional varieties, Darwin’s theory states that natural selection preserves the modifications which are conducive to the species survival and eliminates those that are not, which replaces the new form each generation. Darwin questions why we do not see transitions embedded in the earth preserved by nature. He states that when similar and different species’ habitats are shared, the neutral territory between them causes them to become rare or extinct. The process of natural selection is slow and is affected by weather, climate, and habitation and it will pause until conditions become favorable for the modifications to occur. In addition, Darwin states that time spans of modifications have varied and some have been exterminated during the process. “Some modifications can be proven through fossil remains and have had intermittent and imperfect record” (Darwin). Structural modifications and changes in habits change simultaneously. Darwin questions our assumptions in having a Creator who thinks like a human. He admits that others question his theory and he also has questions about the transformations from generation to generation. The possibility of the Metamorphoses of organs and the theory that natural selection perfects each generation to be superior to the environment in which it lives as it struggles for survival is a remarkable idea for Darwin. Natural selection is not a means for perfecting one species to assist or destroy another; it is only a means for its own survival. Although Darwin states that others have objections to his theory of natural selection in evolution, he agrees there are many factors, such as; no connections in the gradations of life nor the habits of life of varying species which are unexplained. Darwin recognizes the difficulties associated with explaining his theory of natural selection and he describes the gradations from generations passed down as “Unity of Type” and he describes the habits from species to species which are passed down through generations as “Conditions of Existence” and they are embraced by natural selection.  Key Points for Middle School Students: //Changes in species occur through generations // //Theorists have unexplained questions // //Survival of the fittest // //Variables in modifications //

Chapter 7: Instinct: Zach Zachry  Instinct Summary: Darwin begins this chapter by saying that instinct had the potential to overthrow his theory. He states that he is not concerned with the origin of “metal powers” and then says that his main focus is on the diversities of instinct and other “mental qualities of animals within the same class”. He says that instinct is usually defined as an action that is performed by many individual animals the same way, old or young, without any specific reason. Darwin continues that many confuse instinct with habit. He says that habits are acquired while instinct is inherited. He uses Mozart as an example of this by saying instead of playing the piano at three with very little practice; he had played perfectly with no practice than he would have been playing instinctively. He says that slight modifications to instinct might be profitable to a species and that if it can be shown that they are able to change then that could be profitable to a species. He believed that a species may have different instincts at different periods in their life, different times of the year, or under different circumstances …etc, and that natural selection could preserve one of these varying instincts. He says that Audubon has documented different nests of the same species of birds in the southern and northern US. Variation of Instinct is inherited and can be strengthen under domestication. Some pointers will point the first time they are taken out, retrievers retrieve, and shepards will run around a flock of sheep. He then mentions a dog whose great-grandfather was a wolf who shows his wild ancestry by not coming in a straight line when called. Darwin then mentions that natural instincts can be lost under domestication as well. Some chickens will rarely sit on their eggs. He then talks about young chickens that have no fear of dogs and cats. Darwin’s next topic is on how instincts are changed by natural selection. He discusses European and American cuckoos. The European lays eggs in other birds’ nests but the American doesn’t. He says that it is possible that the European’s ancestor had the habits of the American bird and then occasionally laid an egg in another species nest. If that young bird were made more vigorous by the mistake then it is possible that the trait could be passed on. Darwin notes that the European bird has not lost all care for its own young. Darwin goes on to site many examples of how different instincts could benefit a species such as; specific hive building strategies in bees, ants who take slaves, parasitic bees and even sterility in offspring. His idea is that slight modifications can affect communities as well as individuals. Darwin says that none of his examples strengthen his theory but they do not annihilate it either.


Teaching points: Insticts, like other attribute of living organisms can change over time.

These changes if beneficial to the species as a whole, will be passed on to successive generations.

Darwin says that none of his examples strengthen his theory but they do not annihilate it either.

Chapter 8: Hybridism: Amy Crabb What is a hybrid/hybridism? A hybrid is the result of a fertile cross breeding between different species. An example of a hybrid is a mule which is the result of a cross breeding of a horse and a donkey. Darwin had a great interest in the idea of hybridism. He was interested in the thought of breeding varieties with pure species and the offspring that would be a result of the cross, a hybrid. Darwin’s initial statement on hybridism is that intercrossed species have been endowed with the quality of sterility, as to not create confusion in species. However, through Darwin’s extensive experiments and tests, results revealed a variety of conclusions to his theory. First, Darwin’s experiments were primarily between species and variety. However, Darwin never really states what a variety is and if there is a difference between it and species. A species is a distinct species and the variety may be a sub species of the species. However, he never states such. In his experiments, he tests the fertility of plants and the theory of the fertility of animals. Here we will look at plants. In the experiments of a pure species and hybrids, Darwin finds that varying results occur in the degree of sterility between pure species and hybrids. He states that the sterility of various species, when crossed, is so different in degree and that the fertility of pure species is so easily affected by various circumstances that it is difficult to determine where perfect fertility ends and sterility begins. He claims that neither sterility nor fertility gives a clear distinction between species or variety. Also, it can not be determined that a hybrid, which should assume to be sterile, would be sterile. Experiments conclude that in some cases that less fertile hybrids can be artificially fertilized with their own hybrid pollen and create offspring that are increasingly fertile and generations are increasing fertile. He states that some hybrids may never produce and some will. The level of their fertility greatly varies. Also, that pure species may never produce and some will. The level of their fertility greatly varies. Further, Darwin continues his experiments and makes additional conclusions such that the belief that sterility can be removed by domestication. He states that we must give up the belief of the universal sterility of distinct species of animals when crossed. This brings Darwin to the theory of environmental factors that may affect the sterility and fertility of such species and variety. Although conditions may be ideal for reproduction, environmental conditions may not be favorable for the offspring. Conditions may vary for embryo survival, therefore affecting the ability to grow. Also, although the hybrid may appear in external appearance to be similar to the pure species parent, it is the internal make up of the reproductive organs that may be abnormal therefore resulting in sterility or a lesser degree of fertility. However, if the reproductive organs of a hybrid are compatible, then there is a greater chance for fertility and offspring to result. Scientific Principle>>>>> In Darwin’s final statement on hybridism, he can only conclude that “the facts briefly given in this chapter do not seem to me opposed to, but even rather to support the view, that there is no fundamental distinction between species and varieties.” Therefore, we can only conclude based on his conclusion, that sterility and fertility is not a factor based on the species or the variety, but that sterility and fertility varies with no true underlying rule.

Chapter 9: Imperfection of the Geological Record: Tasha Wilson

In this chapter, Darwin addresses the lack of intermediate links between species in the fossil record. Many have used this as evidence against his theory of descent with modification though natural selection. When you look at two species, each animal could have several intermediate animals stemming from one common ancestor, known as the progenitor. An example used in the chapter is the fantail pigeon and the pouter pigeon. They are both descended from a rock-pigeon, but no bird species exist that connect the fantail and pouter pigeon directly together. There would have been several intermediates stemming from the rock-pigeon to each species. Natural selection happens very, very slowly and there can be many intermediate species. Geologists have discovered huge blank periods of time that are missing from certain rock formations. Therefore, the rock formations give an incomplete span of time. It is assumed that these lapses in rock formations cover very long periods of time, because of changes in mineral composition. This indicates that the geography of the land has been changing. In the geologic rock formations, any coastal formations have been greatly affected by weathering and erosion. A large part of why our fossil record is inadequate is due to the collections of paleontologists. The Earth has not been thoroughly geologically explored. Only a small part of it has been explored and none of the work so far has been thorough. Paleontologists name species after only finding one specimen or because they found a few of the same specimen in one location. The preservation of remains is also very tricky. Organisms that were soft all over would not have been preserved. If the remains of an animal are left in a place where sediments are not building up, then it will not be preserved. The evidence that terrestrial animals existed during periods such as the Secondary and Paleozoic period is very incomplete. The preservation of the remains of these animals is rare and often accidental. Changes in the geography of the land have caused a loss of sedimentary deposits. In South America, for example, the west coast of the continent was raised several hundred feet in a recent time span. The action of the waves as the land was rising would wear away these deposits. Most of the formations that have been used to find fossils have probably been formed during a time of subsidence. During subsidence, remains may have been preserved over a large area in the ocean. Unfortunately, during subsidence there would have been a lot of extinctions and not many new types of a species coming about. If the majority of our fossils come from this time, then it is easy to conclude that one wouldn’t find many intermediate species in our fossil record. Sedimentary rock formations take a long time to form, but this is considered a short span of time compared with how long it would take one species to change to another species. There are also some species that appear and disappear at different levels of rock formation. This could be due to changes in the land and the migration of an organism. We can’t be expected to see all of the intermediate species of an organism unless the layers of the rock formation were extremely thick and that organism that was changing and modifying itself lived in the same place in that entire span of time.

Key Principles a Science Teacher Could Utilize:

· The fossil record is incomplete. There are large spans of time in which fossils are missing. · Only a small part of the Earth has been explored for fossils. · Organisms that had completely soft bodies were often not able to be fossilized. · Paleontologists have named organisms after finding only one specimen. · Many rock formations have been disturbed by geologic processes. · Most of the rock formations that have provided the most fossils are believed to come from a time of subsidence, from which there would not be many intermediate species. · In order to see all of the intermediate species in a rock layer, the layer would have to be extremely thick and the organism that was modifying itself over time would have to only stay in that one area for the entire time of its existence. Chapter 10: Geological Succession of Organic Beings: Cody Holland ** Chapter 10: **** Geological Succession of Organic Beings ** If the fossil record is important to demonstrate how an organism evolves, then chapter 10 mimics the evolution by building on chapter 9 and leading to 11. In chapter 10 Darwin polishes his arguments that the main downfall of his proposed evolution of species is the fossil record. He reiterates why the fossil record is incomplete and argues that anyone who thinks that all forms of any one species would be captured in fossil is being short sighted. As in chapter 9 he argues that the fossils are rare therefore finding one for every step in the evolutionary chain would be VERY surprising, and not finding several steps is actually much more likely. He gives all the reasons for the scarcity again including the need for special conditions, the migration of species to new areas, the relatively vast areas that are unexplored for fossils, ect… The question then becomes if we cannot expect to find some proof of the evolution of species, what then leads us to believe with any confidence that they have in fact evolved and are not really just a different species that is brought into being or has been here all along? To answer this question Darwin points to the logic that is inherent in his observations. Further he points out that if natural selection is indeed taking place, then one would expect the “newer” models to be better suited to the environment and for competition. This would then lead to the extinction of the parent species as they would be losing the competition to their offspring. These arguments are not new to the chapter however. What he does include is the way that species in a particular geological region tend to resemble the earlier species in the same region. This Darwin refers to as the Theory of Descent with Modification. We would say selective breeding within an area to express the same idea. In this argument, Darwin is saying that since species in a geological area would evolve due to environmental and competition factors, we would expect to see localized differences more readily then large scale adaptations. Once a population becomes locally established that has an advantageous trait, the trait would spread from the localized region and slowly encompass all the species that the original population could reach. For evidence to these theories Darwin points to the fossils found by Professor Owens in caves of South America. “. In South America, a similar relationship is manifest, even to an uneducated eye, in the gigantic pieces of armour like those of the armadillo, found in several parts of La Plata; and Professor Owen has shown in the most striking manner that most of the fossil mammals, buried there in such numbers, are related to South American types.” (http://www.gutenberg.org/files/1228/1228-h/1228-h.htm) Impact on teaching: This chapter reminds us that species must either adapt to compete for food or move to a place where the competition is not as strong. This would lead to localized adaptations eventually moving out to the rest of the attainable landscape. If a species cannot migrate to a different population, or if it migrates to a different population and loses the competition for resources, then the fossil record would not show that step as being successful. If it is able to spread and is successful then the fossil record will show at the very least future generations with the adaptation. Chapter 11: Geographical Distribution: Aimee Farmer In Chapter 11 Darwin proposes that climate, sea levels, and land and sea barriers were not factors in species modification and adaptation to their habitat. While traveling to South America, South Africa, and Australia Darwin noticed that the species were vastly different even though the physical conditions,climate, and longitude locations were similar. He also noticed that the continent of North America was a large and vast land mass with varying climates and physical conditions had similar species that had modified and adapted to their habitat. He and other scientist at the time concluded that physical conditions, climate, and barriers by sea or land were not factors in species migration. These observations lead Darwin to his theory on geographical isolation and the effect on species migration. Darwin believed that species migration occurred during the Ice Age and when the Bearing Strait was a land bridge between Russia and North America. Seeds were spread to different areas of the world by floating through the ocean, dropping from migratory birds flying across different land masses, and from melting Icebergs. Animals traveled, across the land bridge between Europe and America, on migratory paths. When the bridge was covered by water those animals modified and adapted to their location. Darwin believed that species were formed in one particular area and spread through different parts of the world through migration. Darwin rejected the idea that continental shift and island breakaways did not influence migration and species development, a popular theory at the time that he published Species of Origin. Darwin surmised that geographical change and species development were a result of the end of the Glacial period. At the end of this time period there was a uniform climate in which few species survived. The surviving species migrated to cold areas in order to survive. The surviving species did so through modification, natural selection, and adaptation to their surroundings. A science teacher could use Darwin’s theory on geographical isolation and its effects on migration, in the classroom as a foundation to teaching evolution. Darwin’s theory was revolutionary at the time and evidence supports evolution and natural selection. Science had accepted that evolution is a fact. This is an example of how the theory of science has evolved over the last century which can show students how scientific theory evolves and changes over time.Darwin spent long periods of time observing and researching before publishing "On the Origins of Species." His careful research and observations are good examples for student to learn and understand the importance of thorough research and detail observation.

Chapter 12: Geographical Distribution..Cont..: Nicole Carter In this chapter Darwin discusses water life and some of the differences and similarities he found in his studies of fish and shells. One of his experiments was placing duck’s weed in a freshwater aquarium that was stocked with freshwater shells, he then placed a duck in the aquarium. Darwin states, “These just hatched molluscs, though aquatic in their nature, survived on the duck's feet, in damp air, from twelve to twenty hours; and in this length of time a duck or heron might fly at least six or seven hundred miles, and would be sure to alight on a pool or rivulet, if blown across sea to an oceanic island or to any other distant point.” He was alarmed at the fact that the molluscs were able to survive out of the water for any period of time. He discussed that on a two river system, that sometimes one river may have different species than the other river. He believes this to be linked to the different levels of the land and how it has changed over the years, and believes that this has affected how different rivers have flowed into each other. Also the adaptation of fresh water fish to salt water was discussed, and that this may be linked to the fact that they can slowly be adapted to salt water. Darwin discusses that on oceanic islands and in new areas of water, there is not a struggle for existence as would be in an area that is not isolated. Darwin supports the idea that fresh-water plants and lower level animals over time may not change much, but they are dispersed via seed and egg transportation from different areas. He thinks that Mother Nature is a “careful gardener” and the seeds and eggs are dispersed throughout areas. When it comes to the inhabitants of the oceanic islands, he believes that dispersal has something to do with new species on different areas, but that there are other factors as well. Darwin believes that “on oceanic islands best adapted plants and animals have not been created on them, but that man has unintentionally stocked the islands.” He discusses that it is still unknown how some species of animals arrive on different isolated islands. It is easy to believe that shells and plants can be transferred via birds, but harder to believe how land birds are on some remote islands like the Galapagos. I think that Darwin’s beliefs of dispersal are easy to incorporate in the classroom. We could take and study different species that have been and do inhabit local rivers. I think that if the students are able to look at how different species in our area have adapted over time it would make them realize that everything in this world is constantly changing. Also incorporating studies of different species and where they originated from can draw Social Studies into the lessons, because we could take and track how far a specific species has traveled. Students would be able to relate to some of Darwin’s studies when we conduct our own, and go through the Scientific Method of what they believe has happened to a certain species. Chapter 13: Morphology: Krissy Hamilton Darwin addresses two topics in Chapter 13 –affinity, or connective similarities, and morphology. He explains that classification can be rather difficult because of his theory of evolution. Species have continued to evolve, or modify to achieve maximum chance of survival. This leads to “morphology between members of the same class, between parts of the same individual.” Darwin explains that the hardship placed on scientist to classify an individual is that all beings do resemble one another in some aspect. He voices that if similarities in beings were traced back far enough, all would share ancestry. The original method of separating species based on their inhabitance has been proved ineffective due to Darwin’s theory. When classifying groups, any character that could have altered as an adaptive measure to their surrounding should be discarded as irrelevant. Another mistake that Naturalist make in classifying species is to hold certain parts of an individual as a definition of what group they belong. Darwin corrects by stating that the simple characters, that are often overlooked, of individuals can be more important in determining natural history. It is easier to state relation of beings through the sharing of several characters, or traits, than a few large parts. Darwin simply explains that “characters do not give the genus, but the genus gives the characters.” (Darwin, Chpt 13, pg 3) A weaving of traits, not the presences of particular traits, influences his classification methods. Darwin does allow geographic location of groups to give clues for ancestor, but only in very large groups of beings that closely resemble. Now that specific details for classification of groups have been established, Darwin continues to the arrangement of groups in each class. In classifying groups, Darwin focuses on the weaving of several similar traits to point to a certain group but in determining class, Darwin plans to see a much broader degree of modification. He explains that the natural history of a family of individuals can be viewed much like a pedigree of a dog; each individual will have a different level of modification that the whole group has experienced. The amount of similarity present among the groups will then be ranked into families, sections, orders, and classes. The trait that is consistent throughout the group will be used to classify various varieties. Species are determined by the “closeness of descent with various degrees of modification.” (Darwin, Chpt 13, pg 6) It is important to find a similar character, no matter how small, that all share to establish a requirement for that species. A common trait can be especially helpfully when stating relation of species that have very different environments. Larvae cannot be trusted to classify varieties because male and female larvae can be widely different. The beings that have modified the least are the most important tool in discovering genealogy. Darwin voices that extinction does cause a loss of pure traits but the surviving species may have adopted other species ways. This results in several species appearing to be related to one another. In this way, extinction has widened the standards for several groups. Darwin states that “we shall never disentangle the inextricable web of affinities between members of any one class.” (Darwin, Chpt. 13, pg 17) Each adaptation, or morphological advancement, that an individual makes can affect other parts. Darwin states that we all started with the same “tools” but due to environmental demands, the bats needed to fly and the horse needed to run, then each species has morphed. It is not the same part in each class that has been altered. For the bat, it was arms. For the horse, it was legs and neck. For a crab, it was his jaws. How I would implement this information in my class would be very simplistic. It is important for the class to understand that we may not look the same but that it is different degrees of adaptations that have happened over the course of man that speaks for our differences. I would also use the opposite stating that just because there are a few modifications among us, does not mean that we do not share a common ancestry. I think that it is important to note that Darwin himself quotes different scientist in his research. Some great scientific theories will come from original thought or observation but some will come from the disagreement of other scientist work. This section would be great to let the students write about how they think we will change in the next thousand years.

Chapter 14: Recapitulation: Amanda Pruett Chapter fourteen of the //Origin of Species//, Darwin simply restates his argument of why his theory of natural selection is viable. Attempting to defend his ideas, Darwin begins by detailing all of the reasons against his theory, including the evidence of fossil records. This is the most objective and solid piece of evidence against Darwin’s views. He claims that the records are imperfect and too few compared to the existing number of species, and that the records do not clearly reveal the variations and mutations in organisms. The last part of chapter fourteen consists of the supporting facts of Darwin’s theory. Darwin believes that all organisms/species must have descended from similar parents and originated in one region and migrated to another. He goes on to say that all being could not have been individually or specifically created because such organisms like the “upland geese” have webbed feet and rarely, to never swim. This supports the idea that each species is constantly trying to increase in quantity with the help of natural selection ready to adapt. He defends the theory of natural selection by saying that all organisms have reached their current state by “innumerable slight variations” that are passed through inheritance by reproduction. According to Darwin, these variations are produced by “the use or disuse of, and direct and indirect actions of conditions.” Also, the variations paired with a large population increase cause a struggle for existence, and/ or natural selection, which is a fight for existence due to the less adequate forms. The scientific principle behind Darwin’s theory is that of natural selection and survival of the fittest. All species originated from one set of parents and through innumerable variations have arrived at what they are today. Due to these variations, we are all in competition with one another for resources and only the “fittest”, or those who can adapt or tolerate their surroundings will survive/propogate.