natural selection

5. the whole number of people or inhabitants in a country or region
8. the science or practice of farming, including cultivation of the soil for the growing of crops and the rearing of animals to provide food, wool, and other products
9. a core principle of evolutionary theory, explaining how populations of organisms change over time
12. relating to genes or heredity
13. a change or the process of change by which an organism or species becomes better suited to its environment
15. Darwin was a British naturalist, geologist, and biologist

1. the deliberate modification of the characteristics of an organism by manipulating its genetic material
2. a person's child or children
3. a distinguishing quality or characteristic, typically one belonging to a person
4. the continued existence of organisms which are best adapted to their environment, with the extinction of others, as a concept in the Darwinian theory of evolution
6. a process where humans deliberately select and breed organisms with desirable traits, essentially controlling which individuals reproduce
7. an animal that is caught and killed by another for food
10. the natural home or environment of an animal, plant, or other organism
11. an animal that naturally preys on others
14. an individual animal, plant, or single-celled life form