Environmental variation

Genetic variation

Variation is not inherited

The stripes warn other animals that wasps and bees are dangerous

The stripes are attractive to birds and other predators

The stripes make them look like harmless hoverflies, so they can sneak up on their prey

Warm and Dry

Cold and Moist

Warm and Moist

Cold and Dry

It is more difficult to hear in hot air, so bigger ears are needed

Big ears lose heat quickly, while small ears lose heat slowly

Big ears are useful for creating a breeze when they are flapped quickly

Respiration

Photosynthesis

Volcanic activity

40% of the chemical energy stored in coal is transferred to electrical energy

60% of the chemical energy stored in coal is transferred to electrical energy

40% of the chemical energy stored in coal is transferred to the surroundings as heat

60% of the chemical energy stored in coal is transferred to the surroundings as heat

15,000 J

250 J

25 J

The more distant galaxies are moving the slowest.

The more distant galaxies are moving the quickest.

The more distant galaxies are moving towards us.

13,700 million years

1,370 million years

137 million years

They move more quickly, so their pitch increases

Their frequency increases, so their pitch increases

Their wavelength increases, so their pitch increases