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0:01
[Music]
0:15
Hello, I am Dr. William Schlosser, Washington State University, School of the Environment, and this is my classroom!
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Ecological systems can be viewed in a hierarchy, launching from individual organisms to the biosphere. We covered that in a previous discussion, but now we make a landing at the initiation of this journey to look closely at those groups all of one species. When many species are taken together, we find a population. Populations of different genetic makeups interface everywhere they are found. These interactions are between plants, between
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plants and animals, and between animals. Interfaces are competitive or even mutually beneficial, these come in many flavors. These interactions are all at the biotic level of consideration. When we look into the entire interface realm, we capture biotic and abiotic space. The combination of population genetics and population ecology is called evolutionary ecology. It is focused to the implications of natural selection considering physical and behavioral
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adaptations. Speciation holds a central theme. By examining species adaptations, physiological ecology is concerned with the responses of individual organisms to temperature, moisture, light, and other abiotic conditions. Associated with community ecology is landscape ecology, the study of causes behind landscape patterns and spatial ecological consequences. We can understand these relationships as we study them. We use the Scientific Method to grow understanding.
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When we consider ecological relationships, we consider the way in which two or more concepts, objects, or entities are connected. It is the state of being connected. Plants and animals in the natural environment have relationships with other plants and animals all within the realm of the environment they live in. These relationships lead to actions and reactions, some minor, some pervasive. This is where I generally ask, “what do wildlife need from their Environment?”
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But now you can ask “What does the environment need from the wildlife?” We will continue to explore this question. We have been talking about biotic and abiotic conditions across our globe, and now we will dive in deeper to the conditions of plants and animals: the biotic side. When we consider populations of plants or animals, we need to do it in consideration of WHERE the populations exists. In our last discussion we talked about Douglas-fir trees, and how Pseudotsuga menziesii has been
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geographically separated at the Cascade Mountain range to lead to variety menziesii in western Washington, and variety glauca on the east side. In allopatric speciation, groups from an ancestral population evolve into separate species through a period of geotemporal separation. Speciation is the process by which new species form. They started as one species, then through separation and genetic selection, a new species evolved.
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It is seen where spatially isolated groups become reproductively isolated and genetic diversion from their ancestral population is witnessed. Each population responds to the specifics of the environment where they live. It takes generations for these changes to happen. The First Stage is separation. Speciation usually begins when a part of a population becomes separated from the rest of their species. The second stage is genetic adaptation as seen through genetically favored selection
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of those offspring with favorable traits to thrive and survive in the environment where they live. These genetic traits are passed to their offspring. And the third stage is known as reproductive isolation, meaning there is no genetic mixing of the separated populations. This is speciation.
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The images you see now are from Yellowstone National Park, in Wyoming. The relationships we explore reveal several interactions between plants, between plants and animals, and between animals. Relationships are the way in which two or more subjects are connected, or the state of being connected. A science is both a body of knowledge and a process of inquiry involving intellectual and practical activities. These integrate systematic studies of structural
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behavior and the physical and natural world. Ecology is like studying the place you live. You may share furniture, desks, rooms, food storage preparation utilities, the air you all breathe. You are responding to what “other organisms” in your environment are doing. Your responses are reactive. It can be living or non-living things. It includes physical, chemical, and other natural forces. They constantly interact with it and adapt
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themselves to conditions in their environment. This Yellowstone National Park environment refers to considerations in a meadow, forest, on the hillslope, in the soil and in the air. Relationships are complex in that each organism not only responds to the abiotic environment but also modifies it and, in doing so, becomes part of the broader environment itself. The trees in the canopy of a forest intercept the sunlight and use this energy to fuel photosynthesis.
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In so doing, the trees modify the environment of the plants below them, reducing the sunlight and lowering air temperature. Birds foraging on insects in the litter layer reduce insect numbers and modify the environment for other organisms that depend on this shared food resource. Some benefit from this interaction, others need to change the way they forage.
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We see interactions between two individuals of the same species, these are Intraspecific Interactions. Deer interact in the same environment, they share space, breed to make fawns; they continue the population. These intraspecific interactions are shaped by genetic traits of responses and reactions the species has genetically attained. These intraspecific interactions are seen between individual Rocky Mountain Elk, they
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live in the same population. Their success on the site is genetically carried to their offspring. This is how phenology is capitulated to physiognomy. Phenology the study of cyclic and seasonal natural phenomena, in relation to climate, plant, and animal life. Physiognomy is the art of discovering temperament and character from outward appearance. Species effectively thrive and survive on the sites where their genetic makeup has been tested and applied for generations.
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The genetic result is how these species will all look similar, share genetic traits, and all succeed equally on the sites where they live. They carry this water in a bucket of heritability.
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Interspecific interactions occur when the actions, traits, or density of individuals of one population result in a change in some attribute of another species' population. This is easily seen as competition between this deer and elk. They live in the same space, compete for the same foods, water, shelter, and they both serve as prey for the same carnivores. The main types of interspecific interactions include competition, both are ultimately losers (-/-),
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predation, where one gets a full tummy and the other is the lunch (+/-), mutualism when both parties gain (+/+), commensalism when one benefits and the other knows nothing was set to benefit or loose (+/0), and parasitism where the parasite gains at the cost to the host (+/-). These are topics we will cover in more detail in future discussions. Just keep in mind that we will put these players into categories of similarity, like these herbivores, the primary consumers we identified
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earlier. They each seek the photosynthesizing plants they need to eat for their growth. Only photosynthesizing plants are capable of making new energy, and the herbivores come to gain by eating them. In this respect, the deer and bison are eating primary producer plants, but the bison grazes grasses while the deer is pulling shrub leaves. They are joined by the elk who nibbles from those leaves, but some eat grasses and others browse randomly across the platter.
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This is the realm of herbivores, making the most out of their individual situations. Still, they are each in competition with each other. As we step out of the herbivores only crowd, we need to identify the carnivores of this landscape. Grey Wolves interact with deer, elk and buffalo. This is a prime interspecific interaction and where we see predation in its most primal example. Of course, the wolf is rarely seen as a solidary hunter. Through the wolf’s intraspecific relationships
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with the other wolves of its pack, the phonologically heritable traits are shared to guarantee they will hunt together. The success of one is the success of the pack. Although each level in the ecological system hierarchy has a unique set of questions on which ecologists focus their research, all ecological studies have one thing in common: they involve the process known as the scientific method. This method demonstrates the power and limitations of science, and taken individually, each step
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of the scientific method involves commonplace procedures. These techniques form a powerful tool for understanding nature. All science begins with observation. In fact, this first step in the process defines the domain of science: if something cannot be observed, it cannot be investigated by science. The observation needs not be direct. For example, scientists cannot directly observe the nucleus of an atom, yet its structure can be explored indirectly.
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Each observation must be stated in clear and absolute terms. Form the question asked as definitive and purposeful. Allow it to be termed so that multiple observers could test it. This constraint helps to minimize unsuspected bias when an individual might observe what they “want” or think they “ought” to observe. In this second step, as you define the problem, ask the question regarding the observation. For example, an ecologist working in Yellowstone
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National Park might observe that the growth and productivity of sagebrush varies across the landscape. From this observation the ecologist may formulate the question, “what environmental factors result in the observed variations in sagebrush productivity across the landscape?” The question typically focuses on seeking an explanation for the observed patterns. Once a question, or problem has been set, the hypothesis puts the question into a testable statement.
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A hypothesis is an “educated guess” about what the answer to the question may be. The process of developing a hypothesis is guided by experience and knowledge, and it should be a statement of cause and effect that can be tested. For example, based on knowledge that nitrogen availability varies across the different soil types, and that nitrogen is an important nutrient invigorating plant growth, the ecologist might
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hypothesize that the observed variations in the growth and productivity of sagebrush across the landscape are a result of differences in the availability of soil nitrogen. As a statement of cause and effect, certain predictions follow from the hypothesis. If soil nitrogen is the factor limiting the growth and productivity of plants in this ecosystem, then sagebrush productivity should be greater in areas with higher levels of soil nitrogen than in areas with lower levels of soil nitrogen.
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The next step is the experimental stage where you test the hypothesis to see if the predictions follow your estimates. Of course the step from Experiment to Analysis is often blurred as one moves to the next. This is where clear and precise documentation is applied. As your analytical results are defined, analysts need to determine if the data support the hypothesis made. When it does not, then you circle back to the hypothesis stage.
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Form the statements of investigation again. Remake your hypothesis, experiment and analyze. Follow it through to find your new knowledge. When your analytical findings are verified, set and are consistent, you have an Evidence Supported mark. It is now time to publish your findings so others can benefit from your new knowledge. You have a new publication with your name on it and others can test these results and build on it headed to the next finding.
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Scientific inquiry allows for isolated discoveries of new knowledge to make coherent and comprehensive statements about the natural world. The science of ecology captures knowledge about the relationships between biotic and abiotic environments. This is what we do, and how we make it memorable. Natural environments include the array of organisms that coexist within their confines. This is what ecologists refer to as ecosystems. We have seen it through the lens of an ecological
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hierarchy, but now you can also see how organisms interact with the environment in an ecosystem context. The terrestrial vegetation type may be forest, steppe, grassland, semi-arid, desert, or wetland. Fresh water habitats include marshes, streams, rivers, lakes, ponds and estuaries, and marine habitats include salt marshes, the coast, and the intertidal zone. Each of these present a different living environment, abiotic and biotic environmental complex where life happens.
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Biological Interactions are the effects that the organisms have on one another. Biophysical interactions involve the effects of the physical environment on organisms. The biophysical environment is the biotic and abiotic surrounding of an organism or population. It defines life. The input and decomposition of dead organic matter is a key factor in the development of forest soils. Biophysical interactions involve the effects
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of the physical environment on organisms. Biophysical environment may also be defined as the physical environment of water and soil as well as the biological activity within them. This is the complex of biotic, climatic and abiotic factors that act upon an organism, be it a plant or an animal. These factors act upon an organism and determine its form, survival and how it adapts through time. The biophysical environment can vary in scale
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from microscopic to global. All life that has survived must have adapted to conditions of its environment. Temperature, light, humidity, soil nutrients; all influence any species within its environment. Environmental science is the study of the interactions within the biophysical space. This is the combination of biotic and biophysical interactions. The combination effects of these two kinds of interaction creates a composite, a complex, and interconnected network of ecological influence
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that can be called the ecological environment. Ecology is the study of the relationships between living organisms, including humans, and their physical environment; it seeks to understand the vital connections between plants and animals and the world around them. The Biotic Environment is an expression of the LIVING world. An organism's habitat refers to an ecological or environmental area inhabited by particular species of plants, animals, or fungi. The term environment refers to the biotic,
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or living part, while the abiotic is the non-living factors. Life must adapt to specific environmental conditions, all of them experienced together. Water, Temperature, and Light define potential of life yielding forces. Keep those 3 close to you. Look for them. TALK about them. You remember my urge to TALK in this learning space. Make it count.
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Let’s take a jump from Pullman to the Grand Teton National Park to observe the ecosystems and habitat of Rocky Mountain Elk. The diversity of organisms comprising the community modify as well as respond to their surrounding physical environment, and so together the biotic and abiotic components of the environment interact to form an integrated system; this is the ecosystem. At this level, the emphasis shifts from species
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to the collective properties characterizing the flow of energy and nutrients through the combined physical and biological systems. Organisms are adapted to survive with the food, water, shelter, and space conditions of their natural habitats. For example the natural habitat of elk is the forest and rangelands, although like many species, elk can adapt to a variety of habitats. The environment in which an animal lives in
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is referred to as its habitat. A habitat is a place where living things live. Animals have basic needs for air, water, food, shelter, and space. When they find it, they make a life out of it. Here we are, in the winter, it is cold, dry, limited light and solar radiation; these are the attributes we need to make recognition of. The elk are adapted to these conditions. As we expand our perspective even further, the landscape can be viewed as a patchwork of ecosystems whose boundaries are defined
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by distinctive changes in the underlying physical environment. At the landscape level, questions focus on identifying factors that give rise to the spatial extent and arrangement of the various ecosystems that make up the landscape, and ecologists explore the consequences of these spatial patterns on such processes as the dispersal of organisms, the exchange of energy and nutrients between adjacent ecosystems, and the propagation of disturbances such as fire or disease.
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These elk are adapted this this cold and dry landscape. The winter has melted away, grasses are sprouting, shrubs are making new growth flush. Cows have calved. It is warm, moist, high level of light and solar radiation. As a species, living in the environment, sharing the habitat, the herd concentrates on protecting the young, collectively they are recovering from winter weight loss and they are building energy for the approaching summer and fall.
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An ecosystem is basically the neighborhood where animal lives. The habitat is the animal's address in that neighborhood. Autumn has arrived, it is hot, dry, there is a high level of light and solar radiation bears down on all participants in this ecosystem; plants and animals. Look at this herd, those ribs you could count in the Spring photograph, are not visible anymore. They have recovered and are putting it on for the coming winter. What are these elk doing?
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Their heads are down, they are feeding, not drinking, a couple sentries are standing guard. Are wolves and grizzly bear in this ecosystem? Sure they are and they are part of the ecosystem we observe. All species exist in a restrictive environment and form adaptive responses to thrive and survive.
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I have been walking you along this journey with a lot of attention given to deer, elk, bison, and wolves. That is only a slice of the wildlife at the grand Teton National Park. But more, there are plants and those individuals each face the same challenges of the restrictive environment scenario. Plants have similar relationships with their environment, for instance, Mountain Big Sagebrush can occur on the valley floor and at higher elevations on the mountain slopes with contrasting
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physical environments within their habitat. The plants are part of the ecosystem and interact with other plants, animals, and the physical environment. Their genetically adaptive responses facilitate how the species can fill the niche through competition with other plants.
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The ecosystem concept describes the interactions between living organisms and the nonliving environment. An ecosystem is a dynamic complex of plant, animal and micro-organism communities and their non-living environment interacting as a functional unit. Habitats are the physical area where a species lives. A habitat should not be confused with an ecosystem: the habitat is an actual place in the ecosystem, whereas the ecosystem includes both the biotic and abiotic factors in the habitat.
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It is very common to see this type of depiction of temperature and moisture scales and how a plant has one range area, while an animal feeding on it interacts within a different scale. These realms overlap, but they are not identical, so obviously elk are not feeding only on sagebrush. TALK about that one and apply it to natural world around you.
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We began with an individual organism, examining the survival processes it uses, and considered constraints it faces in maintaining life under varying environmental conditions. Each individual organism forms the basic unit in ecology. This is where investigations begin. Physical environments set a series of expectations for all participants in this survival theme. The collective assets individuals drive the dynamics of populations, and individuals of
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different species interact with each other in the context of the community. Most significantly, each pair of individuals, through the process of reproduction, passes genetic information to successive individuals, their offspring, defining the nature of individuals that will define future populations, communities, and ecosystems. This is a journey of survival of the reproductively most successful participants.
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At the individual level we can begin to understand the mechanisms that give rise to the diversity of life and ecosystems on Earth. [Music]
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