Natural Selection

2. a method of dating artefacts by looking at the layer of soil it was found in
3. group of organisms that can interbreed to produce fertile offspring
5. Ardi, Lucy and Tarkana Boy are examples of these
9. the range of differences of a trait in a species
10. example of an antibiotic
11. show the evolution of the brain by how complex they are made over time
12. the fossil that no longer has long big toes, has shorter arms and a larger brain than Ardi
13. the substance which kills bacteria
15. what we call it when bacteria aren't killed by antibiotics

1. the fossil with a chimp-sized brain, long arms, long big toes on hand-like feet
4. the way in which inherited characteristics of living things change over time
6. the fossil that has the brain which is almost the size of a human's and human-like arms and legs
7. who developed the theory of evolution
8. some organisms are more likely to survive because their variations are more suited to this
14. the element you calculate in a dead living thing to estimate when it died