Evolution

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Across:

3. "Survival of the ________" (7)
7. Changes in the ______________ of certain genetic sequences lead to evolution (11)
8. Process of gradual change in the characteristics of a population. (9)
9. Type of selection which results in a new mean by less favourable organisms being selected to reproduce. (11)
11. Type of genetic transfer found in prokaryotes where genes are transferred between contemporary members of the population. (10)
12. Type of selection practiced by humans to improve strains of domesticated organisms. (10)
14. Random increase or decreasein the frequency of genetic sequences. (7,5)
15. Type of selection where pressure is exerted on the extremes, and the mean remains constant. (11)
16. Type of speciation where 2 groups live in close proximity but still become genetically isolated. (9)
17. Type of barrier to speciation where organisms may have different mating rituals. (11)
18. Process where some genes are chosen and some are not chosen. (7,9)

Down:

1. Regions where several organisms vary in their ability to interbreed. (6,5)
2. Type of genetic transfer where genes are transferred from parent to offspring. (8)
4. The formation of new biological species. (10)
5. Barrier, such as a river, which prevents 2 populations from interbreeding. (12)
6. He proposed the theory of natural selection. (6)
7. Believed to account for the differences in the percentages of a population possessing certain blood groups. (7,6)
10. Type of speciation where gene flow is prevented by a geographical barrier. (10)
13. The fate of a population which fails to breed and produce fertile offspring. (10)
15. Type of selection that results in the increase in frequency of genes that increase the reproductive success of the species. (6)