ECOLOGY ONLINE STUDY
Take the first step toward understanding how animals, plants and the non living environment interact together and have an inter-dependence that is important to all of these components of the environments we live in (both natural and man made). This course provides an important foundation for one very important area of environmental study. This course is a very valuable one to take; whether you plan to (or already) work in environmental management, agriculture, horticulture, research, education or any other relevant industry.
Student Comment: "I love the course and the course material even though a bit of it seems to be a lot more in depth than I anticipated. I love it just the same as I'm learning lots. I just wish I had more time to do a lot more." Kim Stinton - Australia, studying Introduction to Ecology as part of an Advanced Certificate in Wildlife Management.
Lesson Structure
There are 7 lessons in this course:
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Ecosystems & Populations
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Components of an ecosystem, Biomes, Detrital & grazing webs, trophic levels, energy flows etc
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The Development Of Life
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Lifespans, Natural selection, Genetics, Understanding arguments for and against theory of evolution, etc
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Animals, Parasites & Endangered Species
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Comparative anatomy, how animals fit in ecosystems, animals in the human community, parasites, etc
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Fungi, Tundra, Rainforests & Marshlands
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Physiology, anatomy, classification and ecology of fungi; Location, the climate, the plant and animal life
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related to different systems including tundra, marshes and rainforests.
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Mountains, Rivers & Deserts
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Formation ecology and importance of mountains (including erosion, volcanoes etc), formation & types of rivers, catchments, dams, deserts and their ecology, etc.
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Shallow Waters
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Shore lines, coral reefs, intermediate reefs, estuaries, sandy shores, etc.
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Ecological Problems
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The Greenhouse Effect, The Ozone Layer, Poisons & Waste Materials
Each lesson culminates in an assignment which is submitted to the school, marked by the school's tutors and returned to you with any relevant suggestions, comments, and if necessary, extra reading.
Aims
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To identify the components of an ecosystem and how they interact.
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Discuss the basis of the Theory of Evolution and those elements of science which influenced the theory.
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To discuss the existence of animals in the ecosystem.
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To discuss the presence of plant life in a range of ecological situations
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To discuss the ecological features of mountains, rivers and deserts.
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To discuss the ecological features of shallow water regions and coral seas.
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To discuss the ecological implications of human activities on the environment.
What You Will Do
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Observe an ecosystem in your local area.Identify the inhabitants of the ecosystem and their location in the food web of that system.
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Compare the similarities and differences between the detrital web and the grazing web
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Discuss what scientific discoveries the Theory of Evolution, both past and present, is based on.
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List and explain the four arguments of evolution.
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Define Natural Selection.
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Discuss how genetics are related to evolution.
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Go to an ecological environment (as natural and un-human interfered as possible) and observe the plants and relationships that exist.
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Visit a local stream or river. Observe the condition of the stream, particularly the presence of indigenous vegetation and its affect on stream bank condition. Also look for evidence of human activity on the condition of the stream or river
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Discuss, in your own words, the theories which have been advanced in the past regarding the formation of coral reefs.
Why Do We Need to Understand Ecology?
All life on earth is connected -animals, plants, humans. The way in which we are interconnected is critical to our long term survival. When these interconnections are not sustained properly; a species runs the risk of declining in numbers, and possibly even becoming extinct.
The Causes of Endangerment or Extinction
Species become extinct for a number of reasons:
The destruction of habitats. This the primary cause and is affected by the following:
• The drainage of wetlands
• The conversion of shrub lands to grazing lands
• The cutting and clearing of forests. This is especially true in the tropics, where
o the rainforests will be completely eliminated by the year 2010 if destruction
o continues at the present rate.
• Urbanisation and suburbanisation
• Highway construction.
• The construction of dams.
As the remaining habitats become fragmented into 'islands' the animal populations crowd into these smaller spaces, thus causing further destruction of habitats.
The species in these small "islands' lose contact with other populations of their own species. This reduces the genetic variation, and makes them less adaptable to environmental change. These small populations are highly vulnerable to extinction (e.g. from natural disasters such as fires), and for some species, the fragmented habitats become too small to support a viable population.
Since the beginning of the seventeenth century, the commercial exploitation of animals for food and other products has been the cause of many species becoming extinct or endangered. For example, the slaughter of the great whales for oil and meat brought them to the very edge of extinction, before international treaties restricted the harvesting of these animals. The African rhinoceroses that are killed for their horns have also become critically endangered. In the nineteenth century the great auk and the American passenger pigeon became extinct because of over hunting, while the California parakeet became extinct because of a combination of habitat destruction and over hunting.
The introduction of diseases, parasites and predators, against which the indigenous flora and fauna have no defence, has also exterminated or greatly reduced some species. For example, blight was accidentally introduced to the North American hardwood forests with the result of the complete elimination of chestnut trees. In Australia, the introduction of species such as cats and foxes has resulted in the extinction of at least forty species, probably the greatest rate of modern extinctions seen in any country, as well as the decline of many other species.
Predator and pest control can also have adverse effects on the ecosystems, for example in America, excessive control of prairie dogs has led to the near elimination of one of their natural predators, the black footed ferret, while in Australia the introduction of the cane toad to control pests in sugar cane crops, has seen that animal become a major pest in it's own right, threatening many native species.
A further problem is the introduction of exotic plants. They often thrive in their new homes, particularly when they are no longer exposed to diseases or predators or climatic controls that may have kept them in check in their original habitats. In Australia, for example, many introduced species have become environmental weeds displacing indigenous vegetation, while in places such as South America and the United States of America, Australian plants have become major environmental weeds there.
Another important cause of extinctions is pollution. Toxic chemicals and especially chlorinated hydrocarbons such as dichloro-diphenyl-trichloroethane (DDT) and the polychlorinated biphenyls (PCB's) have become concentrated in food chains. This affects mainly those animals which are at the end of the food chain, where the accumulation of such chemicals reaches its highest concentration.
Both DDT and PCB's interfere with the calcium metabolism of birds. This causes soft-shelled eggs and malformed chicks. PCB's also impair reproduction in some carnivorous animals.
Water pollution and increased water temperatures have wiped out endemic races of fish in several habitats. Pollution will be dealt with in greater detail in a later lesson of this course.
