Variation, classification and adaptation

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Unit 4
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• Variation, classification and adaptation

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Variation

• All living things vary in the way they look or
  behave.
• Living things that belong to the same species are
  all slightly different.
• Living things that belong to different species
  are so different that they cannot reproduce
  together.
• Inheritance, the environment or a combination of
  both may cause these differences.

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Classification

• Living things are divided into kingdoms.
• There are six main kingdoms virus, bacterium,
  protist, fungus, plant and animal.

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Keys

• Use of keys is an important feature of work on
  variation and classification, e.g.
• animals
• backbone no backbone
• hair no hair legs no legs
• dog frog ladybird worm

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Which of these is an animal?

• cow
• grass
• boy
• spider
• elephant
• worm

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Characteristics

• Every person is unique.
• Each person has characteristics which make them
  distinguishable from other human beings.
• Even identical twins, human clones, will acquire
  scars and behaviours which will distinguish them
  from each other.

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Variation

• We vary partly because of the random way our
  characteristics are inherited.
• The environment can affect most of our
  characteristics.
• It is usually a combination of genetics and
  environment that determines how we look and
  behave.
• Some characteristics are not affected by the
  environment, e.g. eye colour, natural hair
  colour, blood group, ability to roll the tongue,
  certain inherited diseases.

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Databases

• Using a simple database
• Data can be collected
• Data can be organised
• Data can be analysed
• Data can be represented in a number of different
  ways

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Ecology

• Plants and animals interact with their
  environment to create habitats.
• Ecology is the study of these interactions.
• The world is divided into a number of large
  regions called biomes.
• Each biome is characterised by a particular
  climate.

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Biomes

• Tundra biome very cold
• Coniferous forest biome cold
• Temperate forest biome varied but cool
• Grassland biome dry
• Savannah dry
• Desert very dry
• Tropical rainforest hot and wet

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Habitats

• The place where a plant or animal lives is its
  habitat.
• Some habitats are very small and are called
  microhabitats.
• A habitat has to supply all the needs of the
  animals and plants that live in it.
• The animals and plants that share a habitat are
  locked together in an interdependent community.
  They form a food web which is dependent on the
  energy from the sun.

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Adaptation

• In a community, the animal or plant best adapted
  to its surroundings will survive.
• Predators have adapted to survive by being
  strong, agile and fast. They have good vision
  and often a camouflaged body. They may also hunt
  in packs, have a variety of prey, and frequently
  hunt the young, sick and old.
• Prey have also adapted the best adapted escape
  and breed. Prey may be able to run, swim or fly
  fast. They often stay in large groups. They may
  have a horrible taste. They may have warning
  colours or camouflage.

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Competition

• Populations cannot keep growing out of control.
• Animals have to compete for space, food and water
  in their struggle to survive.
• Only those fitted to the opportunities and
  limitations of their environment will survive
  survival of the fittest.
• Plants compete for space, light, water and
  nutrients.
• If a living organism can adapt to its environment
  then it will survive and breed.

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Limiting factors

• Factors which keep a population from becoming
  too large are called limiting factors
• Amount of food and water available
• Predators or grazing
• Disease
• Climate, temperature, floods, droughts, storms
• Competition for space, mates, light, food and
  water
• Human activity such as pollution or destruction
  of habitat.