Homework Sourse1 Provide 2 examples of intraspecific competition and 2 exam
1. Provide 2 examples of intraspecific competition and 2 examples of interspecific competition. Cite your sources (16pts). Explain which scenario has more intense competition.
2. Produce a table showing the average number of beans collected by each individual during each foraging experiment (20pts).
An example raw data table is provided below – you are required to make a summary table from this information (hint: do not include raw data, only summary values, in a summary table).
3. Produce a bar graph (or bar graphs) reporting the experiment averages with appropriate error bars for each foraging experiment (16pts).
4. Provide null and alternative hypotheses for each foraging experiment—a total of 5 sets of hypothesis. (6 pts)
(hint: the 5 hypotheses will be (1) intraspecific competition between small beaked birds (experiment A), 2) Intraspecific Competition between large beaked birds (experiment B), (3) interspecific competition for small beans (experiment C), (4) Interspecific competition for large beans (Experiment D), 5) high vs. low density intraspecific competition (average A vs. average E).
5. Perform appropriate statistical tests for each hypothesis (12pts).
(hint: you are attempting to find out if there is a significant differences between two populations – for (i) and (ii) the statistical test will be paired and for (iii) the statistical test will be unpaired)
6. Discuss the results of each statistical test, and explain why you observed these patterns (15pts).
7. Explain how competition—both intraspecific and interspecific—drove the evolution of Darwin’s finches (below) to develop specialized beak shapes? What do the different species compete for, and why are differences in morphology (e.g. bill shape and size) important? (15 pts)
Treatment
A
B
C
D
E
Low Average A
High Average E
Competition
Intraspecific
Intraspecific
Interspecific
Interspecific
Intraspecific
Beak size
Small
Large
Large
Small
Large
Small
Small
Bird Density
Low
Low
Low
Low
High
Food
Small (Black)
Large (Large White)
Small (Black)
Large (Large White)
Small (Black)
Trial
Tweezers
Tweezers
Tongs
Tongs
Tweezers
Tongs
Tweezers
Tongs
Tweezers
Tweezers
Tweezers
Tweezers
Low Tweezers
High Tweezers
1
9
4
13
13
9
14
14
11
7
7
7
13
2
12
7
11
8
8
14
16
9
10
9
4
4
3
8
6
7
7
11
18
12
14
3
8
8
10
4
6
7
12
6
15
20
16
14
14
12
6
6
5
8
8
12
13
12
6
16
10
10
6
7
4
6
8
11
21
9
14
14
14
15
13
6
11
8
7
14
16
7
11
16
10
21
14
5
8
9
10
8
8
4
15
13
12
15
20
10
16
11
8
8
9
7
9
8
10
13
10
10
13
5
8
12
10
10
9
10
14
14
11
13
15
13
13
16
9
9
11
16
14
16
14
10
10
17
18
10
9
9
7
12
9
6
12
13
13
3
19
13
10
9
9
5
13
14
9
13
11
16
12
13
14
4
4
6
8
14
13
12
12
11
10
15
16
17
11
10
6
6
15
14
6
15
9
16
19
13
15
13
13
12
7
16
6
10
16
12
10
7
14
11
7
15
13
3
17
8
5
11
18
10
8
19
16
2
3
4
7
18
6
15
12
12
13
7
12
15
9
12
5
11
19
9
5
12
14
14
16
12
12
0
5
8
10
20
10
19
15
15
11
7
16
10
11
10
8
5
| Treatment | A | B | C | D | E | Low Average A | High Average E | |||||||
| Competition | Intraspecific | Intraspecific | Interspecific | Interspecific | Intraspecific | |||||||||
| Beak size | Small | Large | Large | Small | Large | Small | Small | |||||||
| Bird Density | Low | Low | Low | Low | High | |||||||||
| Food | Small (Black) | Large (Large White) | Small (Black) | Large (Large White) | Small (Black) | |||||||||
| Trial | Tweezers | Tweezers | Tongs | Tongs | Tweezers | Tongs | Tweezers | Tongs | Tweezers | Tweezers | Tweezers | Tweezers | Low Tweezers | High Tweezers |
| 1 | 9 | 4 | 13 | 13 | 9 | 14 | 14 | 11 | 7 | 7 | 7 | 13 | ||
| 2 | 12 | 7 | 11 | 8 | 8 | 14 | 16 | 9 | 10 | 9 | 4 | 4 | ||
| 3 | 8 | 6 | 7 | 7 | 11 | 18 | 12 | 14 | 3 | 8 | 8 | 10 | ||
| 4 | 6 | 7 | 12 | 6 | 15 | 20 | 16 | 14 | 14 | 12 | 6 | 6 | ||
| 5 | 8 | 8 | 12 | 13 | 12 | 6 | 16 | 10 | 10 | 6 | 7 | 4 | ||
| 6 | 8 | 11 | 21 | 9 | 14 | 14 | 14 | 15 | 13 | 6 | 11 | 8 | ||
| 7 | 14 | 16 | 7 | 11 | 16 | 10 | 21 | 14 | 5 | 8 | 9 | 10 | ||
| 8 | 8 | 4 | 15 | 13 | 12 | 15 | 20 | 10 | 16 | 11 | 8 | 8 | ||
| 9 | 7 | 9 | 8 | 10 | 13 | 10 | 10 | 13 | 5 | 8 | 12 | 10 | ||
| 10 | 9 | 10 | 14 | 14 | 11 | 13 | 15 | 13 | 13 | 16 | 9 | 9 | ||
| 11 | 16 | 14 | 16 | 14 | 10 | 10 | 17 | 18 | 10 | 9 | 9 | 7 | ||
| 12 | 9 | 6 | 12 | 13 | 13 | 3 | 19 | 13 | 10 | 9 | 9 | 5 | ||
| 13 | 14 | 9 | 13 | 11 | 16 | 12 | 13 | 14 | 4 | 4 | 6 | 8 | ||
| 14 | 13 | 12 | 12 | 11 | 10 | 15 | 16 | 17 | 11 | 10 | 6 | 6 | ||
| 15 | 14 | 6 | 15 | 9 | 16 | 19 | 13 | 15 | 13 | 13 | 12 | 7 | ||
| 16 | 6 | 10 | 16 | 12 | 10 | 7 | 14 | 11 | 7 | 15 | 13 | 3 | ||
| 17 | 8 | 5 | 11 | 18 | 10 | 8 | 19 | 16 | 2 | 3 | 4 | 7 | ||
| 18 | 6 | 15 | 12 | 12 | 13 | 7 | 12 | 15 | 9 | 12 | 5 | 11 | ||
| 19 | 9 | 5 | 12 | 14 | 14 | 16 | 12 | 12 | 0 | 5 | 8 | 10 | ||
| 20 | 10 | 19 | 15 | 15 | 11 | 7 | 16 | 10 | 11 | 10 | 8 | 5 |
Solution
Examples of intraspecific competition:
Examples of interspecific competition:
Reference:
Branch, G. M. (1975). Mechanisms reducing Intraspecific competition in Patella Spp.: Migration, differentiation and territorial behaviour. The Journal of Animal Ecology, 44(2), 575. doi:10.2307/3612
Bolnick, D. I. (2004). CAN INTRASPECIFIC COMPETITION DRIVE DISRUPTIVE SELECTION? AN EXPERIMENTAL TEST IN NATURAL POPULATIONS OF STICKLEBACKS. Evolution, 58(3), 608. doi:10.1554/03-326
Retrieved February 26, 2017, from https://www.researchgate.net/profile/Hannu_Yloenen/publication/226399749_Interspecific_competition_in_small_rodents_From_populations_to_individuals/links/566fcd4108ae486986b815b4/Interspecific-competition-in-small-rodents-From-populations-to-individuals.pdf.
Retrieved February 26, 2017, from http://fishbull.noaa.gov/74-1/mason.pdf
