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Habitats, Environment & survival Habitat • Where does an animal live, where can I find it? • What is there address? • The habitat in which they live. • If I am searching for a koala I do not go to an open grassed field, but to a eucalypt forest of certain species Habitat • Unlike you and I, an animal needs to get all its requirements for living from the area in which they live. • They need, light, water, food, shelter, mates, other associated animals etc. • The place that provide this for an animal is known as its habitat. • How many different types of habitat can you think of? Micro Habitats • An animals habitat can be described in more detail as a microhabitat. • In a eucalypt forest there are hundreds of organisms but they don’t all live in the same spot. • A spiders microhabitat may be under the bark, a koala in the trees near new leaves, etc • What microhabitats exist in a reef environment? Community • All the people in our neighbourhood are known as the community. • All the organisms, plant and animals are known as the community of an ecosystem. • What is an Ecosystem? An ecosystem • An ecosystem is made up of both living and non living parts that interact with each other. • Make a list of the non living parts, the living parts, interactions that may occur. Energy in Ecosystems Ecosystem Biotic factors (Living) Abiotic factors (Non-living) Interactions between Biotic & Abiotic factors Biotic • Biotic factors are living things. • • • • • • • • • They include all living organisms They may affect an ecosystem through provision of Food Energy Nutrients Shelter Predators Prey Parasites Abiotic • • • • • • • • • • • • • Abiotic are all non living components of an ecosystem Soil Air Temperature Water pH Light intensity Slope Aspect Topography Rocks Salt Minerals etc Interactions • Light Plant Photosynthesis, energy conversion • Plant Animals, path of energy flow • Light Temperature • Water Animals Water • Light Animal life Range/Distribution • Where a species of animals is found is known as it’s range. • It can be large or small, this has no affect on density of population • A range may be densely or sparsely populated. • The range of the cane toad is expanding, to the detriment of the environment. • Can you think of an animal whose range is decreasing? Range • Fox Range • Rabbit Range Range/Distribution Limitations A number of factors can limit the range of an organism. 1. Abiotic factors – the environment 2. Geography - barriers 3. Biotic factors – competition & predation Environmental abiotic Factors Environmental abiotic factors can limit range distribution • • • • Not hot enough Too much salt Not enough light Not enough water etc Tolerance Range • The tolerance range of an organism indicates what abiotic conditions they can survive in. • Eg light, temperature, rain fall, pH, turbidity, oxygen, UV light, salt etc Tolerance range • An organism has an optimal tolerance range in which they survive and reproduce easily. • A zone of stress, in which they can survive but in poor condition and not necessarily reproduce. • A zone of intolerance where they cannot survive at all. • The wider their optimal range of tolerance the larger there range is likely to be. Tolerance Range • Some animals have huge tolerance ranges being able to survive and reproduce in a large range of environments. • Whilst others have very small tolerance ranges and can only survive in very specific areas. These are the species that are most endanger from human impact. Law of Tolerances • If an organism is outside or on the cusp of it’s tolerance range it has two choices 1. Stay and die 2. Migrate and flee Migration • Animals ranges can increase, spread and move through the migration of the population. • Some animals have a migratory pattern (whales) and others just follow food or inhabit suitable areas as they are provided (locusts and insects) Geographic Barriers • Geographic Barriers also limit range distribution. • There are no foxes in Tasmania (as yet confirmed), they cannot cross the sea. • Geographic barriers can also include things such as large mountains, snow and lava fields. • Can you think of any other animals that have been restricted geographically? Niche • Where have you heard the word niche before? • Niche means way of life or the role of an organism. • Each species has its own niche, they eat, live, reproduce their own way. Niche competition • A niche describes everything about the way an organism lives – place, food source, time of activity, reproductive areas, watering holes etc. • If two organisms exist in a community with the same niche what would happen? Competition : Niche Overlap • When a niche overlap occurs these two species are in competition for a resource. • The resources might be shelter, food, or mating spot. • The main point is two into one cannot go, so eventually one species must lose out. • This can affect their range, if there is already an organism that fills their ‘niche’. Ecological Niche • Lets learn about ecological niches and ways to overcome competition. Law of Tolerances • Investigate the law of tolerances and the effect of niche overlap on the population of organisms.