| Date | November 2015 | Marks available | 1 | Reference code | 15N.1.SL.TZ0.3 |
| Level | Standard Level | Paper | Paper 1 | Time zone | Time zone 0 |
| Command term | Outline | Question number | 3 | Adapted from | N/A |
Question
Draw a sketch graph showing a typical survivorship curve for a “K-strategist” species.
Outline one reason for the shape of the curve from part 3(a)(i) above.
Markscheme
[1] for correctly labelled axes;
[1] for the correct shape of the graph;
[1] for both axes labelled correctly / x-axis age/% of maximum lifespan and y-axis number of survivors/individuals/number of survivors per 100/1000;
[2 max]
Any one of the following:
most K species survive until after offspring bearing age/maturity;
death rate increases near the end of the lifespan;
a few K individuals will die at a young age;
[1 max]
Examiners report
This question proved to be challenging for most candidates. Only a few were able to correctly draw a survivorship curve and label the axis appropriately.
Few candidates were able to correctly answer this question. Most quoted the characteristic of K species e.g. they have few offspring.
