Login

Join for Free!
118840 members
table of contents table of contents

This study examined the pre- and post-copulatory advantage of greater investing males


Biology Articles » Zoology » Entomology » Courtship-role-reversal in the bean weevil, Bruchidius dorsalis (Coleoptera: Bruchidae): Interplay between male-male competition and cryptic female choice » Results

Results
- Courtship-role-reversal in the bean weevil, Bruchidius dorsalis (Coleoptera: Bruchidae): Interplay between male-male competition and cryptic female choice

Female preference for greater investing or larger males

Females showed slight preference for heavier males over lighter males (22 of 36 trials), but the difference was not significant from random mating (Fig. 1, p=0.12, binomial test). Furthermore, there was no significant difference between the weights of seminal fluid ejaculated by the chosen and unchosen males (0.62*/-0.04 mg and 0.52*/-0.04 mg, respectively) (p=0.12, t-test). These results suggest that B. dorsalis females showed no pre-copulatory mate preference for greater investing or larger males.

Relationship between the amount of seminal fluid obtained by a female and the female’s refractory period

Figure 2 clearly shows the tendency that females which received heavier seminal fluid refrained from remating for a longer period, and also that the gradient of the well-fed males was larger than that of the poorly-fed males. The results of ANCOVA shows the analogy to the above tendency (Table 1); the effects of the weight of seminal fluid and the interaction on the refractory period were significant.

Sperm precedence

The developmental rate of eggs was 99.4% (542/545 eggs) for females that mated with only an NR male, but was 0% (0/240 eggs) for females that had mated with only an R male. P2 values were 0.49 and 0.9, respectively, when the last mated males were R and NR (Fig. 3)


rating: 0.00 from 0 votes | updated on: 22 Oct 2007 | views: 4685 |

Rate article:







excellent!bad…