Aggressive Behavior and Aggressive Behavior and Dominance in Dominance in Gerris latiabdominisGerris latiabdominis
2006-10900 Kwak Se Hyun2006-10923 Pak Sun Mi
1. Introduction
1) PURPOSE : Relationship with
Aggressive behavior and Size dominance of G.latiabdominis
What’s the dominance? We define “Dominance” as the one who doesn’t step off earlier
2) Materials : Waterstrider- Gerris latiabdominis- Small species among waterstriders- Abundant in rice field and serene riffles in the mountain
3) Methods :
a) Collecting G. latiabdominisb) Distinguish of Sex : use ONLY FEMALE
In order to exclude mating behavior during aggressive interactions
c) Measuring body size & Separating them into 3 groups : Small / Middle/ Large use ONLY SMALL & LARGE sized individualsd) Starving them for 3 days in order to increase the
frequency of their aggressive behaviore) Observing Interactions between 2 individuals
4)Way to distinguish of sex (a) size : Female is usually larger than male
(b) different shape of genitalia Male: Diamond shape/ Female: Triangular shape
Size Distribution of Male
0
2
4
6
8
10
N =36
NUMBER
Bell-shaped distribution
Few G.latiabdominis have very small
size
Most G.latiabdominis
have middle size
Few G.latiabdominishave very large
size
Size Distribution of Female(1)
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0.99 1.02 1.05 1.08 1.11 1.14 1.17
1) 1st
N=51
NUMBER
: Small size group
: Large size group
Size Distribution of Female(2)
0
2
4
6
8
10
12
0.98 1 1.02 1.04 1.06 1.08 1.1
N=48
1) 2nd
NUMBER
: Small size group
: Large size group
2. Results and Discussion 2.1. Pattern of Behavior
0
20
40
60
80
100
SS SL LL
Nothing
Signaling
FightingHigh Up
N=90 N=90 N=90
(%)
SIGNALING Wave signals produced by Bouncing the body Larger (or Heavier) the body, Stronger the signals Many waterstrider species use wave signals for sending information
FIGHTING The strongest interaction Pushing with legs
HIGH-UP Raising the body with raising mid & hind legs
AGGRESSIVE BEHAVIORS in G. latiabdominis
2.2. Effect of Size
No signal+ Fight + High-up
0.00%10.00%20.00%30.00%40.00%50.00%60.00%70.00%80.00%90.00%
100.00%
SL
S WINNER
L WINNER
N=1
N=10
Gerris latiabdominis’ dominance was highly and positively correlated with body size
SIZE&DOMINANCE
2.3. Effect of Aggressive Behaviors (1) Fighting
0
2
4
6
8
10
12
14
SS
SL
LL
(%)
N=2 N=4
N=10
There is considerably more fighting behavior in the LL group
2.3. Effect of Behaviors (2) Signaling
(a) ROLE OF SIGNALING
27 25
2 4
05
1015202530
SS LL
NU
MB
ER
SP SA
SA SP
N=29 N=29
*SP SA= SP:winner/SA:looser
SA SP= SA:winner/SP:looser
*SP=Signaling Present
SA=Signaling Absent
SPSA make up over 93.1% / 86.2%
(b) Deeper Look about Signaling
0
20
40
60
80
100
SS SL0
20
40
60
80
100
LL SL
The rate of success in Signaling
(%) (%)
N=50 N=19
N=40 N=29
The presence of large one appears to reduce the rate of success in signaling of small G.latiabdominis
Large G.latiabdominis interacting with small
one shows slightly higher rate of success in signaling compared to large one interacting
with large
(b) Deeper Look about Signaling
0102030405060708090
SS SL
++
+/-
0102030405060708090
LL SL
++
+/-
The rate of success in Signaling
N=40 N=29N=50 N=19(%) (%)
•++ : Both G.lacustris signal when they interact each other
•+/- : Only one G.lacustris signal when they interact each other
Proportion of ++
is higher in SL
(a) ROLE OF High-Up
10 10
34
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SS LL
NU
MB
ER
HP HA
HA HP
N=13 N=14
2.3. Effect of Behaviors
(2) High-Up
*HP=High-Up Present
HA=High-Up Absent
*HP HA= HP:winner/HA:looser
HA HP= HA:winner/HP:looser HPHA make up over 76.9% / 71.4%
0
20
40
60
80
100
SS SL
0
20
40
60
80
100
LL SL
The rate of success in HIGH -UP
(b) Deeper Look about High-Up
N=18
N=9 N=22 N=13
The presence of large one appears to reduce the rate of success in high-up of small G.latiabdominis
(b) Deeper Look about High-Up
0
20
40
60
80
100
SS SL
++
+/-
0
20
40
60
80
100
LL SL
++
+/-
The rate of success in HIGH -UP
N=18 N=9 N=22 N=13(%)
(%)
Proportion of ++
is higher in SL
•++ : Both G.lacustris signal when they interact each other
•+/- : Only one G.lacustris signal when they interact each other
2.3. Effect of Behaviors (3)SIGNALING AND HIGH-UP
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HSP A
NU
MB
ER
SS+LL
N = 10
Both high-up and signaling shows strong effect on dominance of G.latiabdominis
3. Conclusion
• G.latiabdominis’ aggressive behaviors are composed of fighting, signaling, and high-up.
• Positive relationship > New DISCOVERY!
- Body size and dominance
- Signaling and dominance
- High-up and dominance