Question 19N.2.SL.TZ0.1g
| Date | November 2019 | Marks available | [Maximum mark: 4] | Reference code | 19N.2.SL.TZ0.1g |
| Level | SL | Paper | 2 | Time zone | TZ0 |
| Command term | Discuss | Question number | g | Adapted from | N/A |
Using all of the data, discuss whether there is evidence that the two sub-species of O. sativa might have evolved independently from O. rufipogon.
[4]
a. large difference in diversity index between O. s. indica and O. s. japonica «suggests independent evolution» ✔
b. «some of the» peaks/troughs for O. s. indica and O. s. japonica in different positions «suggests independent evolution» ✔
c. O.s. indica has a similar diversity index to O. rufipogon «which suggests closer relationship/recent divergence» ✔
Allow converse for japonica
d. O.s. japonica has very different proportions of ancestral and derived alleles compared to O. s. indica ✔
e. O.s. indica has similar large number of ancestral alleles to O. rufipogon I/II ✔ Allow converse for derived
f. O.s. japonica has a large number of derived alleles similar to O. rufipogon III
OR
«but» the number of derived alleles is greater in O. s. japonica than in O.rufipogon III ✔ Allow converse for ancestral
g. O.s. indica and O. s. japonica are in different clades ✔
OR
O.s. indica and O. rufipogon I are in the same clade ✔
h. evidence from one chromosome/3 genes/2 studies is not sufficient to form a conclusion ✔
