Compendium Review: Unit 4: Chapter 22, 23, & 24

Compendium Review: Unit 4: Chapters 22, 23, & 24 Human Landscapes and Ecology Table of Contents: I. Introduction II. Deep Time Evolutionary History A. What is Deep Time? 1. early Earth 2. Stanley Miller experiments B. Evidence for Historical Fact of Evolution C. Humans are Primates 1. fossil record 2. accident of history 3. comparison Neanderthal & modern human 4. humans today III. Natural Selection A. How Does Evolution Happen? IV. Physical Landscape A. Water Cycle B. Carbon Cycle C. Greenhouse Effect V. Biological Landscape A. Ecology & Human Ecosystem 1. relationships among species B. Development of Agricultural Systems 1. relationship with domesticated species 2. resource use (evolution of domesticate relationships) 3. domestication today i. example: E. coli ii. example: guinea pigs VI. Conclusion

Life consists of many complex components. Some of the complexities of life contain such areas as the structures and functions of the cell, the many organ systems, like the circulatory system and the digestive system, the sensory input and motor output of the nervous system, the body structures of the muscles and bones, and the importance of the reproduction, like the reproductive systems and the development of a new individual. The list can continue on, but the understanding of where life actually started and developed from is also an entire realm of density itself. To understand this perspective it can be examined from the aspects of deep time evolutionary history, natural selection, physical landscape, and biological landscape.

The understanding of evolution of the Earth and life can be viewed upon the feature of deep time evolutionary history. Time to any individual cannot be grasped in its entirety due to the fact that it extends beyond what anyone is capable of understanding. It extends so far beyond days, week, years, and centuries that it resembles the depths of deep space. There is one way that deep time can be understood and that is from the perspective of the toilet paper analogy. A toilet paper roll of 200 sheets can represent the history of life on Earth, starting 4 billion years ago. And, each sheet on that roll represents 20 million years. For example, the first sheet on a 200 sheet toilet paper roll would stand for the formation and solidification of Earth that occurred 4.6 to 4 billion years ago. And, in the development of human existence, that would be inherent in the shreds of the end of the last sheet of toilet paper. In the development of the early Earth, several things are evident.
The early Earth, “…probably formed from aggregates of dust particles and debris” (Mader 468) that was located in deep space. Its atmosphere in the past was nothing in comparison of what it is presently. It first contained gases of water, carbon dioxide, and nitrogen that came from the landscape of many volcanoes and was turned into dense clouds of water vapor, due to the extreme temperatures of heat. Then, as the Earth slowly began to cool, the clouds released enormous amounts of rain, producing the body of oceans. This caused the available gases in the air to intermingle with the water of the oceans. In the surrounding environments of the newly developed oceans, energy availability of eruptions from volcanoes and lighting caused the gases in the water to cultivate the small organic molecules of amino acids and nucleotides. Then, the small organic molecules, “…joined to form proteins and nucleic acids, which became incorporated into membrane-bound spheres” (Mader 468). This created an organism that could operate cell metabolism but could not reproduce, called the protocell. The protocell survived by ingesting preformed food and the process of fermentation. Eventually over the many years of deep time, the protocell was able to acquire genes of DNA, enzymatic proteins, and reproduce, creating the true cell. The true cell is what exists today. This information was developed from existing rocks that were found around the world that date back to at least 3.8 billion years ago and from the Stanley Miller Experiments.
The Stanley Miller Experiments were first performed in 1953. In the experiment, a mixture of gases that were similar to the early Earth’s atmosphere was placed within a closed system of heat and electric sparks. First, the gases were heated and then traveled throughout the contraption, where it reached an electrode creating the spark. Then, it was diffused through a condenser, where the hot water was released and the cool water was contained. After it cooled, Stanley Miller found the small organic molecules that were also believed to have developed in the early Earth. In accordance with the development of the first true cells, comes the development of evolution.
Figure 1: The Stanley Miller Experiment

Evolution is, “…the process by which a species changes through time” (Mader 470). And, there are several pieces of evidence that attribute to the historical fact of evolution. The first piece of evidence is the fossil record. The fossil record is the history of life that is found from fossils in rocks, bone, shale, tree resin, worm casts, preserved droppings, and footprints. And, most of the fossils that are found are located within sedimentary rocks that are housed within sequences of layers, called a strata. It is within the ancient sedimentary rock that the species that are found are not species that are alive today. This shows that life has created a long-term change in biological communities, from particular fossils called transitional fossils. The transitional fossils have characteristics that provide the information of who is related to whom and how evolution happened. It can be found within the developments of the unicellular prokaryotes to multicultural eukaryotes, to the fish, plants to flowering plants, amphibians to reptiles, reptiles to dinosaurs, and dinosaurs to birds, mammals, and humans. The second piece of evidence is anatomical similarities. In vertebrates, the forelimbs are used for actions of swinging from tree branches, climbing, running, swimming, and flight in accordance with related species. Although, differing actions in vertebrates occur, all of the forelimbs have the exact sets of bones that are also organized the exact same. This shows that the layout for the forelimb belonged to a common ancestor that was modified in the proceedings of each vertebrate’s course of evolution. Also, there are embryonic characteristics that are also shared amongst vertebrates. During some point of embryonic development, “…all vertebrates have a postnatal tail and exhibit paired pharyngeal pouches” (Mader 473). This shows that fishes must have been inherited to groups of other vertebrates. And, the third piece of evidence is the shared biochemical and genetic features. All living organisms have within them the same basic biochemical molecules such as, DNA, ATP, and enzymes. And, the use of the DNA sequences and the 20 amino acids in proteins are also used within all organisms. This shows that the relatedness within organisms must of came from common descent. The historical facts of evolution can also be applied to the vertebrates called humans.
The evolution of humans can be shared with the closest living relatives of monkeys and apes. Therefore, humans are primates. Human’s evolutionary history can be based upon the working hypothesis of the evolutionary tree. And, this tree shows that all primates are assigned to a common ancestor. For example, humans are most recently linked with apes, but are also linked with monkeys (farther into deep time) and lemurs and tarsurs (much farther into deep time). But, the species that are alive today are not the human’s species tangible ancestors; rather they are distant cousins that divulged from a common species 70 million years ago. In order to see the development of the human species (primates), the investigation of the fossil record needs to take place.
The fossil record of primates provides evidence of the closest evolutionary humans today. In the fossil record, events of discovered primates are charted along a series of time and within the different groupings of particular fossils that were found. For example, Homo neandertalensis (Neandertal) is directly linked to the same ancestral line as humans. But, not all the fossils that have been discovered, like Homo habilis (2 million years ago), are in direct lineage of Homo sapiens, or humans. It mainly displays the fact that many different human and human-like varieties lived either separately or together in deep time history that evolved from a mutual antecedent. Today, there is solid verification that the living human species has formed one single species, called homosapiens. And, this is due to the occurrence of accident history creating that one species. In the past, there existed Homo neanderthalis and Homo floresiensis, both linked by DNA and protein analysis that shows lineage relation, but in present day, there is little anatomical and biochemical difference between Homo sapiens. And, humans also interbreed, which did not occur with other species of Homo. In unity with humans and neandertals, there are several areas that relate in comparison.

Figure 2: Fossil record of homo-species from a common ancestor
There are several areas that relate between modern humans and neandertal. One similarity is that, “…neandertals are considered the first early humans to bury their dead intentionally” (student webs.Colorado college.edu/~h_landry/an101102.htm). These intentional buried sites had occurred around 300,000 years ago and consisted of corpses in holes covered with rocks and dirt, were complemented with personal items, and sometimes bared limestone rocks that signified gravestones. This provides evidence that the neandertals had an emotional connection with death and the probability of the belief in an afterlife. Another similarity is cultural practices. These practices consisted of living within caves or homes that were built out in the open, the use of tools to hunt and for food preparation, and fire control to cook and keep themselves warm. But today, humans dominate the planet and are present within most landscapes. Along with the development of the human species, the history of evolution also occurs by the process of natural selection.
Figure 3: Comparison of neandertal & modern human skulls

Natural selection is, “…the process by which favorable traits that are heritable become more common in successive generations of a population of reproducing organisms, and unfavorable traits…are less common” (en.wikipedia.org/wiki/Natural_selection). The development of biological evolution, which was founded by Charles Darwin, was provided the contribution of natural selection. And this is how the process of evolution occurs over deep time. There are three elements that make the process of natural selection. The first is variation. Variation allows each member of a particular species to have physical characteristics that contrast. Then, these different physical traits are passed on from generation to generation by means of inheritance. The second is competition for limited resources. Due to the limited availability of resources within an environment, individuals are no longer liable to producing many descendants. Instead, the number of reproduction in populations stays the same, because the competition for means of survival creates an unequal amount of descendants in a particular species. And, the third is adaptation. In terms of natural selection, the species that have traits that are more favorable in a given environment tend to capture more resources and are able to reproduce, passing on the favorable traits. Then, over time, the environment chooses the favorable traits that were able to adapt much easier, creating following generations that are modified for the given environmental standards. For example, the animal species of giraffes all started with differences in neck length. As competition for resources increased, the giraffes that had the longer necks were able to get the limited resources that were available and were able to produce more offspring. And because of the process of natural selection, most species of giraffes have the characteristics of long necks. Along with the evolution of species, the evolution of the Earth also took on several characteristics.

As the Earth evolved from the early Earth to present day, it created several characteristics of its physical landscape. They are the water cycle and the carbon cycle. The water cycle is a process that contains six steps. The first step involves the procedures of water evaporating and water turning into condensation. For example, the sun causes, “…freshwater to evaporate from seawater, and the salts are left behind” (Mader 499). Then, condensation takes place as it creates clouds within the atmosphere. The second step involves the event of precipitation. For example, as the condensed freshwater has finished rising into the environment, rain, snow, sleet, hail, or fog falls over the land and oceans. And, in the third step, the evaporation of water also takes place from the land and plants. In step four, the precipitation that was delivered to the land is enclosed inside lakes, ponds, streams, rivers, and groundwater. It is from the actions of gravity, due to the land being above sea level, that the fallen precipitation is eventually delivered back to the ocean. This process happens in step five of the water cycle, which is called runoff. Also in step five, water that does not runoff saturates the earth by means of sinking into the ground. And the sixth step involves aquifers. The water that did sink into the ground can also be located within rock layers that release the water and deliver it via wells and springs. These rock layers can also be refilled when continuing precipitation exists. This is the main role of aquifers that are located within the Earth. Unfortunately, humans have had effects on the water cycle’s normal processes. For example, instead of the creation of water buildup in aquifers, human activities have withdrawn the available water within them; humans have cleared the land’s landscape, preventing precipitation to sink into the ground and increasing the process of runoff; and, humans have added pollutants to water that has damaged the water’s natural methods of decontamination. Another physical characteristic of the Earth is the carbon cycle.
Figure 4: The processes of the water cycle.

The carbon cycle is a process that contains six steps. The first step involves plants and their chemical process of photosynthesis. For example, carbon dioxide that is emitted into the air is taken up by plants. Then, photosynthesis allows for the plants to transform the carbon into needed nutrients. The second step allows for the recycling of carbon to take place. For instance, when organisms breathe out carbon. This form of carbon is delivered back to the environment and is subsequently used by the existing plants. In step three, “…carbon dioxide from the air combines with water to produce bicarbonate ion…” (Mader 500). Then, this substance is used is used by algae and heterotrophs. In accordance with step three, step four follows the process of diffusion, which allows for the bicarbonate (produced in step three) and carbon dioxide in the air to create an equilibrium. The fifth step involves living and dead organisms. For instance, all living and dead organisms are made of carbon. And, this adds to the carbon cycle by means of the amounts of organic carbon within trees and from the decomposition of organisms. And, the sixth step involves fossil fuels. For example, during the course of deep time, the remains of organisms were transformed into coal, oil, and natural gas, which are called fossil fuels. Unfortunately, due to human activities within the carbon cycle, the greenhouse effect is taking place. The increase of carbon that is being released into the atmosphere can be accounted for the human activities of burning fossil fuels and the destruction of forests. This disrupts the natural order of the carbon cycle, making it prone for the buildup of greenhouse gases. They are called greenhouse gases, because the buildup of excess carbon gases creates a process of the passing of low light from the sun through clouds, but not allowing intense heat from the sun to return back to space. Instead, the intense heat is returned back to the Earth, causing a rise in temperature, also known as global warming. Another course of evolution that has occurred on Earth is the development of the biological landscape.
Figure 5: Processes of the greenhouse effect

The biological landscape has provided the development of ecosystems (all organisms, including humans) and agricultural systems. The development of ecosystems has allowed for species, of all types, to live within adaptive communities. These species are able to develop particular relationships due to the process of co-evolution. And, within these communities, there are particular relationships among species that can beneficial, damaging, or neutral for the species involved. There are five different ways that these relationships can occur. The first is symbiotic, where the relationship is beneficial for both species. The second is parasitic, where one species reaps the benefits, usually a parasite, and the other species is harmed, usually the host. The third is commensal, where one speices benefits from the relationship and the other species is left unharmed. The fourth is mutualism, where the relationship is beneficial for both species, but appearance wise, it may seem that one species has the advantage over the other species. It is seen in the long term, that both species actually benefit. And, the last is predation, where the relationship between the species is damaging (the predator is parasitic and the prey is the host), but can also be defined as mutalism. In terms of relationships with the human species, the development of agricultural systems has taken place.
Human relationships with other species has resulted in mutulistic traits, due to evolution of agricultural systems. These developments allowed for the human species and species used in agriuculture to co-evolve into domestication, allowing for these species to take advantage of the process of evolution and producing more descendents. For example, there is a larger prevalence of dogs compared to wolves, horses compared to zebras, and corn compared to teosinthe that are domesticated, because of particular traits that stood out and were taken into consideration by the human population. And, due to the strong relationships with domesticated species, it has caused a basis for food and agriculture, transportation, care and protection, and laboratory study and production. There are also other relationships with the considered “wild” species such as, the creation of game reserves and national parks, household pests, symbiotic microorganism, and parasitic microorganisms. It is from these developed relationships within agricultural systems that the dependency of resource use is apparent.
In accordance with evolution, the survival and value of the human species greatly depends on the domesticated relationships. And, it is important that these relationships continue. In the past, over the history of deep time, large mammals have been known to become extinct, but this can possibly change if the human species conscious spirits can uphold positive relationships with species, allowing for domesicatin to become a part of the Earth’s natural form of progression. Although the processes of domestication in the past allowed for the human species to recognize other species, the domestication processes that have occurred in present day are very different.
Domestication today have developed around laboratories and survival indoors. For example, within the environment of the laboratory, the domestication of E. coli has become very evident. The reason why the human species likes the E. coli species is due to four things. First, E. coli is a very adaptable species and can reproduce under a wide variation of laboratory environments. Second, E. coli is very easy to visualize particular processes that are occurring within the species. Third, the genes and proteins of this species are very easy to access by the human species and manipulate within laboratory settings. And lastly, the internal nucleuses of the E. coli species can be easily found and altered. The E. coli species also tends to like the human species, because of several reasons. One point is the fact that humans provide a safe environment, such as the lab, for E. coli to reproduce successfully. And, the human species provides new virulent strains of E. coli assessable to the original species, allowing it to build more strength and power. But unfortunately, the manipulations of the E. coli species has developed anti-biotic resistant species of E. coli, which is detrimental to the environments outside the laboratory. Another example is the domestication of the guinea pig. The guinea pig was originally a “wild” speices within high mountain regions, but was discovered by the human species by means of their rapid reproduction rate. This caused the domestication of the guinea pig by ways of livestock, laboratory animals, and pets. Overall, domestication today has provided some open doors and some roadblocks in terms of evolutionary relationships.

Life consists of many complex components. But, the understanding of where life actually started and developed from is also an entire realm of density itself. To understand this perspective it can be examined from the aspects of deep time evolutionary history, natural selection, physical landscape, and biological landscape. Deep time evolutionary history contains many facets of development from the early Earth, like the development of macromolecules into the true cell that functions today, historical facts of evolution, like fossil records, anatomical similarities, shared embryonical features, and shared biochemical and genetic features, to the development of humans. The process of natural selection contributes to the progression of evolution by ways of varitation, limitation of resources, and adaptation. The physical landscape of the evolved Earth today, processes the cycles of water and carbon, but both have been altered by human activities and has even created the greenhouse effect. And, the biological landscape of the evolved Earth had allowed for species to create relationships within communities, that has benefited both human species and species used in domestication. The process of evoltuion will keep continuing into the future of deep time that will hopefully will provide positive survival for the Earth and its species.

Sources:
Works:
Human Biology 10e. Mader, Sylvia S.
student webs.Colorado college.edu/~h_landry/an101102.htm
en.wikipedia.org/wiki/Natural_selection
Pictures:
physics.uoregon.edu/.../Chap28/FG28_002.jpg
www.ariadne.no/Ariadne/Essay/Bilder2002/nitte...
anthro.palomar.edu/homo2/images/Neandertal_mo...
upload.wikimedia.org/.../400px-Water_cycle.png
www.world-nuclear.org/.../graphics/ueg1-1.gif