Question 20N.3.HL.TZ0.7
| Date | November 2020 | Marks available | [Maximum mark: 4] | Reference code | 20N.3.HL.TZ0.7 |
| Level | HL | Paper | 3 | Time zone | TZ0 |
| Command term | Describe, Outline | Question number | 7 | Adapted from | N/A |
The large tree finch (Camarhynchus psittacula) communicates through singing. The frequency (pitch) of a finch’s song was recorded. The results for a short period of the song are shown.
[Source: Reproduced / adapted with permission. Podos, J., Southall, J.A. and Rossi-Santos, M.,
2004. Vocal mechanics in Darwin’s finches: correlation of beak gape and song frequency. Journal of Experimental
Biology, 207(4), pp.607–619. Published by The Company of Biologists 2004. doi:10.1242/jeb.00770. Permission
conveyed through Copyright Clearance Center, Inc. https://jeb.biologists.org/content/207/4/607.]
Outline the trend in large tree finch song frequency.
[2]
a. (the pattern/unit is) a low frequency followed by higher frequency;
b. the same pattern/unit is repeated;
c. range limited to specific frequencies;
Most candidates could generally outline the trend, but some had difficulty expressing it clearly and correctly.
Describe the role of inheritance and learning in birdsongs.
[2]
a. early birdsong pattern is genetically determined/innate;
b. later birdsong pattern is modified based on learning from adults/other birds;
OWTTE
Most candidates knew that birdsongs had an inherited and a learned component; it was more difficult for some to accurately put it into words and attribute the role of birds of the same species in the learning process.
