Ecology: An Explanation

Transcription

1 Ecology: An Explanation

2 Define Ecology - study of the interactions that take place among Biosphere - part of Earth that supports life, including the top portion of Earth's crust, the atmosphere, and all the water on Earth's surface Biotic living organisms Abiotic non-living material

3 Define Biome - large geographic areas with similar climates and ecosystems Includes: TUNDRA TAIGA DESERT TROPICAL RAINFOREST TEMPERATE RAINFOREST DECIDUOUS FOREST DESERT GRASSLAND

4 Define Organism one of any living thing Population - all the organisms that belong to the same species living in a community Community - all the populations of different species that live in an ecosystem

5 Define Ecosystem - all the living organisms that live in an area and the nonliving features of their environment Habitat - place where an organism lives and that provides the types of food, shelter, moisture, and temperature needed for survival Niche - in an ecosystem, refers to the unique ways an organism survives, obtains food and shelter, and avoids danger

6 Define Limiting factor - anything that can restrict the size of a population, including living and nonliving features of an ecosystem, such as predators or drought Carrying capacity - largest number of individuals of a particular species that an ecosystem can support over time

7 Define Pioneer species - a group of hardy organisms, such as lichens, found in the primary stage of succession and that begin an area's soil-building process Climax community - stable, end stage of ecological succession in which the plants and animals of a community use resources efficiently and balance is maintained by disturbances such as fire.

8 What is an ecosystem? An ecosystem refers to all the animals, plants, and nonliving things found in one place, and the way they all interact together. Different plants and animals live in different ecosystems. Different ecosystems can be close together. Some animals belong to several ecosystems.

9 What is an environment? Everything that affects an animal makes up its environment where it lives, the weather and all the living things it comes into contact with. Every living thing, including people, has an effect upon the environment.

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11 Animal Adaptation All living things have to be suited to their environment pass on their genes. They must adapt (change) to the environment if they want to survive. Carnivore - meat-eating animal with sharp canine teeth specialized to rip and tear flesh Herbivore - plant-eating mammal with incisors specialized to cut vegetation and large, flat molars to grind it Omnivore - plant- and meat-eating animal with incisors specialized to cut vegetables, premolars to chew meat, and molars to grind food

12 Define Succession - natural, gradual changes in the types of species that live in an area; can be primary or secondary Primary succession takes where no soil exists Secondary succession takes place where soil is already present

13 How is the seal adapted to its environment? Streamlined shape. Strong teeth to catch fish. Hind legs have evolved into a a strong rudderlike tail. Thick layer of body fat to keep it warm. Forwardfacing eyes for clear vision ahead. Flippers to help it swim.

14 Homes and Habitats The place where an animal lives is called its habitat. An animal lives where it can find food, water, shelter and a mate.

15 Living things All living things (organisms) need food (nourishment) to live. Living things in an ecosystem depend on each other for food.

16 Herbivore Animals that eat ONLY PLANTS are called herbivores (or primary consumers). Carnivore Animals that eat OTHER ANIMALS are called carnivores. carnivores that eat herbivores are called secondary consumers carnivores that eat other carnivores are called tertiary consumers Omnivore - Animals and people who eat BOTH animals and plants

17 Define Carnivore eat omnivores or other carnivores [other consumers] Herbivore eat producers Omnivore eat producers and consumers

18 Carnivores Some animals, like the kingfisher, eat only other animals. These animals are called carnivores.

19 Herbivores Some animals do not eat other animals. They survive on plants and are known as herbivores.

20 Omnivores Some animals, like us, eat both plants and animals. These animals are called omnivores.

21 Define Producer - organism, such as a green plant or alga, that uses an outside source of energy like the Sun to create energy-rich food molecules Consumer - organism that cannot create energy-rich molecules but obtains its food by eating other organisms Decomposer consume wastes and dead organisms

22 Producers Plants are living organisms. They need nourishment to survive. Plants do not eat other plants or animals. Receive nutrients from dead matter Plants are called producers, because they make their own food inside themselves.

23 Consumers Consume means eat. Animals are consumers because they eat (consume) food provided by plants or other animals.

24 Define Predator an animal that hunts and kills other animals for food. A predator is a consumer [carnivore or omnivore] Prey an animal that is hunted and caught for food. Prey is a consumer; it may be a herbivore, omnivore, or carnivore.

25 Predator A predator eats other animals. Cats eat fish. So do bears!

26 Prey Any animal which is hunted and killed by another animal for food is prey. Predator Prey

27 Match the predator to its prey.

28 Predators and Prey Some animals are predators, some are prey - some are both. The predator eats the prey, and the prey gets eaten by the predator.

29 Why there are more herbivores than carnivores? This screen will disappear in 3 minutes Seconds Remaining.

30 In a food chain, energy is passed from one link to another. When a herbivore eats, only a fraction of the energy (that it gets from the plant food) becomes new body mass; the rest of the energy is lost as waste or used up by the herbivore to carry out its life processes (e.g., movement, digestion, reproduction). Therefore, when the herbivore is eaten by a carnivore, it passes only a small amount of total energy (that it has received) to the carnivore. Of the energy transferred from the herbivore to the carnivore, some energy will be "wasted" or "used up" by the carnivore. The carnivore then has to eat many herbivores to get enough energy to grow. Because of the large amount of energy that is lost at each link, the amount of energy that is transferred gets lesser and lesser.

31 Define Food chain - chain of organisms along which energy, in the form of food passes. An organism feeds on the link before it and is in turn prey for the link after it. Food web - Complex network of many interconnected food chains and feeding relationships; a group of interconnecting food chains

32 Food Chains A food chain shows what is eaten. The fly is eaten by the thrush.

33 Food Chains A food chain shows what is eaten. The lettuce is eaten by the rabbit.

34 Food chains always start with a plant. The lettuce is eaten by the slug, the slug is eaten by the bird.

35 Food Chains - a Reminder A food chain shows which animals eat other animals or plants. Plants don t eat things. A food chain starts with what gets eaten and the arrows point towards what does the eating. Food chains only go in one direction.

36 Where do the arrows point?

37 The top of the food chain. Some animals are said to be at the top of the food chain. This is because they are not hunted by other animals. No other animal hunts the lion. The lion is at the top of the food chain. Can you think why?

38 Food Webs In the wild, animals may eat more than one thing, so they belong to more than one food chain. To get the food they need, small herbivores may eat lots of different plants, and carnivores may eat many different animals.

39 Food Webs We can show this by using a food web, which is just a more complicated version of a food chain. owl fox rabbits mice grass seeds berries

40 Breaking the Chain Organisms living in a habitat depend on each other. If one part of a food chain dies out or is greatly reduced, the consumers have to find alternative food, move away, or starve. This then affects more consumers in the same way.

41 Define Energy flow through an ecosystem - the movement of energy through an ecosystem through food webs. The transfer of energy from one organism to another.

42 Define Energy pyramid a way of showing energy flow. As the amount of available energy decreases, the pyramid gets smaller. Each layer on a pyramid is called a trophic level.

43 Energy Pyramid: A diagram that shows the amount of energy that moves from one feeding level to another in a food web. loser5.html

44 Describe each of the following terms:

45 Endangered or Extinct? The number of people in the world is growing at an alarming rate. But this is not true for all animals. In some cases, there are only a few of one type of animal left in the wild. These animals are endangered. If they die out completely, they become extinct.

46 Why does this happen? There are lots of reasons why animals become endangered or extinct. The most common are: loss of habitat (woodlands cut down, rivers drying up, hedgerows removed). chemicals or pollution poison the animals. hunting (for sport, their fur, tusks or meat).

47 Caring for the Environment It is in our own best interests to look after the world we live in. If a habitat is lost or damaged, it has an effect on everything else, even if we do not see or understand it straight away. Remember - once something becomes extinct, it s gone forever!

48 Which diagram best shows the energy transformation from sunlight to chemical energy in an organism? This screen will disappear in 3 minutes Seconds Remaining.

49 B understand that plants are one of the organisms (producers) that make their own food in this process (photosynthesis).

50 This screen will disappear in 3 minutes Seconds Remaining.

51 Choice C is the correct answer because it identifies the greatest limitation of this model. Since food webs are complex, not all organisms can be included in one model. This diagram also illustrates how the flow of energy is represented by arrows in a food web. The energy from the organism that is consumed flows to the consumer. For example, the food energy from the deer flows to the mountain lions because mountain lions eat deer.