Evoloution

• What is evolution?

  A species changes over time
• What are the six key words to describe evolution?

  Mutation, genetic variation, advantage, survive, pass on genes, changes over time
• How did the giraffe evolve to have a long neck?

  A mutation caused genetic variation for a long neck
• What advantage did the long neck provide to giraffes?

  Access to food from taller trees
• How did the anteater evolve to have a long tongue?

  A mutation caused genetic variation for a longer tongue
• What advantage did the long tongue provide to anteaters?

  Access to food in anthills
• What are the three key pieces of evidence for Darwin's Theory of Evolution?

  1. Genetics show characteristics are passed on
  2. Fossils provide records of extinct organisms
  3. Bacteria evolve resistance to antibiotics
• What are fossils?

  Remains of organisms from long ago
• Where are fossils found?

  Inside rocks
• How do fossilized teeth and bones form?

  They are replaced by minerals over time
• What are trace fossils?

  Impressions left by organisms in sediment
• How can fossilized footprints form?

  When a footprint hardens in soft material
• Why does decay not happen in some places?

  Conditions are unsuitable for microbes
• What are two hypotheses about how life first formed on Earth?

  Life evolved in oceans or carbon molecules arrived via comets
• Why is it impossible to prove how life began?

  We have no valid evidence from that time
• Why are there gaps in the fossil record for early organisms?

  Many early organisms were soft-bodied and decayed quickly
• Why might we not know about some fossils that formed?

  Some may have been destroyed by geological activity