662
Singh and Singh
Table I. Experimental Designs for Testing the Effect of Density on
Female Remating Frequency in Drosophila ananassae
|
Cross |
Females |
First males S |
econd males |
|
(A) 2-h daily observation design | |||
|
1 |
Bhutan |
Bhutan |
Bhutan |
|
2 |
ca |
DP |
ca |
|
3 |
ca |
ca |
DP |
|
(B) Continuous confinement design | |||
|
4 |
ca |
DP |
ca |
|
5 |
ca |
ca |
DP |
|
6 |
ct rb |
y |
ct rb |
|
7 |
ct rb |
ct rb |
y |
for 2 h, the number of remated females in each vial was recorded, and re-
mated females were aspirated out. After 2 h of observation, the females and
males were separated by aspiration. Females were stored in groups of six
per vial and the same density was maintained by adding new once-mated fe-
males. Males were discarded. The procedure was repeated on 6 consecutive
mornings. The flies receiving a particular density treatment on 1 day always
received the same density treatment on following days. Two replicates were
run for wild-type (Bhutan) flies.
Table II. Results of the 2-h Daily Observation and Continuous Confinement Re-
mating Experiments at Different Densities in D. ananassae
Number of remated females at
different densitiesa
|
Cross |
2/V |
6/V |
12/V |
24/V |
|
A. 2-h daily observation design | ||||
|
1. Bhutan і × Bhutan × × Bhutan O' | ||||
|
Replicate Ib |
5 |
7 |
4 |
3 |
|
Replicate IIb |
6 |
2 |
4 |
5 |
|
2. ca ‘i' × DP × × ca *** |
2 |
3 |
7 |
10 |
|
3. ca і' × ca × D DP ** |
3 |
5 |
9 |
11 |
|
B. Continuous confinement design | ||||
|
4. cat' × DP × × ca **** |
7 |
10 |
15 |
19 |
|
5. cat' × ca × × DP **** |
10 |
12 |
17 |
22 |
|
6. ctrb , ∣' × y × × ct rb **** |
6 |
10 |
13 |
18 |
|
7. ct rb ‘i' × ct rb × × y ***** |
5 |
7 |
11 |
20 |
a Twenty-four pairs were tested in each cross at each of the four densities.
bVariation between remated and not-remated females nonsignificant (χ2 test from
contingency table). Variation between remated and not-remated females: * P <
0.05; **P < 0.01; ***P < 0.001 (χ2 test from contingency table).