evidence for evolution by natural selection

Question 1

what is evolution

Answer 1

theory that describes how organisms change over time as a result of natural selection

Question 2

what is natural selection

Answer 2

(survival of the fittest) those with the more advantageous phenotypes survive and reproduce passing on desirable characteristics to offspring- passed from one generation to the next by genes in DNA

Question 3

what were Darwin’s observations

Answer 3

-offspring generally appear similar to their parents
-organisms can produce large numbers of offspring
-no two individuals are identical (variation)
-population in nature tend to remain fairly stable in size

Question 4

what were Darwin’s conclusions

Answer 4

-characteristics of parents are passed down onto offspring

-there is a struggle to survive (competition)

-better adapted individuals survive and pass on characteristics

-overtime number of changes may give rise to new species

Question 5

who contributed to the theory of evolution by natural selection

Answer 5

-darwin
-wallace

Question 6

why does allele frequency increase with natural selection

Answer 6

advantageous alleles become more common in the gene pool

Question 7

what is the evidence for natural selection

Answer 7

-palaeontology: study of fossil and fossil record (not complete)

-comparative anatomy: similarities and differences in the anatomy of different species e.g pentadactyl limb = divergent evolution

-comparative biochemistry; DNA sequences, biological molecules, amino acid sequences, rRNA