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Introduction to Ecology Man is much interested in the subjects related to Ecology in view of the problems of environmental pollution, human survival and conservation of natural resources. Ecology is the branch of biology that deals with the study of interactions between organisms and their environment. The science of ecology also studies interactions between individual organisms and their environments, including interactions with both conspecifics and members of other species. Though ecology emerged in the 19th century much of its theoretical structure only emerged in the twentieth century. Though ecology includes a wide variety of sub-fields, philosophical analysis of ecology has so far been restricted to population, community, and ecosystem ecology. Central philosophical problems include explication of relevant notions of ecological diversity and stability the relation between diversity and stability. The term 'ecology' was coined by Ernst Haeckel in 1869, though ecological problems were being studied even before the term was coined. The word is derived from the Greek word 'oikos' meaning 'home' and 'logos' meaning 'to study'. In the words of Haeckel, ecology is 'the study of the total relations of the animal both to its inorganic and to its organic environment, including its friendly and inimical relations with those animals and plants with which it comes directly or indirectly in contact'. There are several other definitions of ecology. Frederick Clements in 1916 defined ecology 'as the science of community'. According to Trailor ecology is 'the science of all the relations of the entire organism to their entire environment'. Clark in 1954 defined ecology as the 'study of interrelation of plants and animals with their environment'. According to Odum, ecology is 'the study of structure and functions of nature'. In 1970, Misra defined ecology in a broad sense, 'as the study of eco systems'. More recently in 1985 Krebs has defined ecology as 'the scientific study of interactions that determine the distribution and abundance of organisms'. So ecology may be generally defined as the study of interrelation between living organisms and their environment. Hence environment is the universe of biotic and other physical elements as organized into dynamic systems. These systems are ecological systems or ecosystems which represent the integration of living (biotic) and non-living (abiotic) elements in the environment. Ecology is the study of relationships among the organisms and between organisms and their surrounding. So there are interconnections and process that really make up 'the environment' which gives us a more fundamental reason to protect it. Ecology is located among the biological sciences and it deals with populations, communities and eco-systems. It is the bridge between the biological and behavioural sciences. Autecology - Autecology is a sub-section of ecology primarily dealing with species populations and how these populations exist in the area and environment they are in. The main goal is to study population sizes and how they change over space and time. The most common example of this is human species overpopulation and how it effects other species. Autecology is the only way we can get the information needed to help prevent things like climate change as well as the destruction of the planet. The fundamentals of autecology are few but very important. The following are fundamentals of autecology. Species population is the total number of a single species. Metapopulation is combining a set of separated population which have some form of migration. A group of nonspecific individuals that is usually separated demographically, genetically, or spatially from other groups. Aggregation is a group of spatially clustered individuals. Deme, which is a set of individuals that are genetically like each other rather than others. The local population can also be measured, which is usually a specific location's population of individuals. And lastly, subpopulation is categorizing and grouping individuals that are picked out through specific traits. The most fundamental law of autecology was made by Thomas Malthus, who made the exponential law of population growth. It states that, "A population will grow (or decline) exponentially as long as the environment experienced by all individuals in the population remains constant.". What this does for autecology is it creates the basis for making predictive theories and tests. Autecology's origins owe much to a couple things, demography (The study of populations, mostly humans) and actuarial life tables (tables that show birth day and death day, as well as possibilities to prevent or increase life expectancy). These two subjects helped created the need for autecology, giving vast amounts of data for scientists to work with. Autecology is a branch of biology, but this does not limit the data gathered to just that branch. Conservation biology relies heavily on autecology. This is because to conserve life, you need to first see what is hurting it, and how it can be changed. The information also helps create PVA (population viability analysis), which is a method that is usually species specific to determine how likely a population is going to last. Mathematicians and statisticians also greatly benefit from this as well. This is because when they are working on population dynamics, information gathered by autecology helps paint a clearer picture for them, and gives them the data they need. Autecology helps many different branches of science, as well as helps create preventative measures to stop overpopulation and climate change. With more information gathered every day, there is no question that scientists will be able to. The real question is, will they be able to make and take these measures in time. Synecology – Synecology, also referred to as community ecology, is the study of a group of organism populations in the same area and their various interactions. This can include many different things, including distribution, structure, demography and interactions that occur between organisms in a same area. This helps us learn about our surroundings, and how various organisms interact with each other, whether peaceably, territorial, or aggressive. Synecology has its roots in European plant sociology. It stems from phytosociology, which is the study of plant communities. These communities were categorized with a specific system, allowing for easy access to the information. Synecology does that, but on a much larger scale, focusing on all communities in nature. Modern synecology focuses on patterns within communities of species and organisms. This includes how many of each species, how much stake each species has in the community, what the species does for the community, as well as how the species eats within the community. It also can get into predatory- prey dynamics and how it effects everything listed before. Synecology's focus is on how different organisms and species interact with each other in each area. This helps create an accessible database of information for scientists to have on a specific region. Many sciences benefit from synecology, but the biosciences (life sciences) benefit the most, being that ecology stems from biology. The way scientists study synecology is through two specific characteristics: genotypic and phenotypic. There are a few theories to go along with Synecology. Holistic theory, created by Frederic Clements, is when species in a certain area, though near each other, are mostly independent from each other. Individualistic theory was created by Henry A. Gleason. He created the concept of an open community, when most a population changes according to the environment. This change happens to individual populations and not all populations equally. This creates communities that would be labeled as discrete, or almost private communities. Natural theory, made popular by Stephen Hubbell, is a hypothesis that does its best to explain abundance of certain species in ecological communities. His hypothesis makes assumptions, such as that members of an ecological community have differences, though none of them are relevant to their success. This means that biodiversity would occur on a random scale, which causes much controversy in the scientific community. Synecology is the basis for how we view communities. Communities exist all around us, from our plants and insects, to the microscopic organisms we cannot see with our eyes. Synecology helps better understand these communities, and with that will help us adapt our lives around it. Levels of Organization – When a discipline such as biology is studied, it is often helpful to subdivide it into smaller, related areas. For instance, cell biologists interested in cell signaling need to understand the chemistry of the signal molecules (which are usually proteins) as well as the result of cell signaling. Ecologists interested in the factors that influence the survival of an endangered species might use mathematical models to predict how current conservation efforts affect endangered organisms. To produce a sound set of management options, a conservation biologist needs to collect accurate data, including current population size, factors affecting reproduction (like physiology and behavior), habitat requirements (such as plants and soils), and potential human influences on the endangered population and its habitat (which might be derived through studies in sociology and urban ecology). Within the discipline of ecology, researchers work at four specific levels, sometimes discretely and sometimes with overlap: organism, population, community, and ecosystem.
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