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Evolution of Pre- and Post-Copulatory Traits in Male Drosophila melanogaster as a Correlated Response to Selection for Resistance to Cold Stress.

Singh K, Samant MA, Tom MT, Prasad NG - PLoS ONE (2016)

Bottom Line: In Drosophila melanogaster the fitness of males depends on a broad array of reproductive traits classified as pre- and post-copulatory traits.Exposure to cold stress, can reduce sperm number, male mating ability and courtship behavior.Additionally, improved performances under stressful conditions need not necessarily trade-off with performance under benign conditions.

View Article: PubMed Central - PubMed

Affiliation: Indian Institute of Science Education and Research Mohali, Knowledge City, Sector 81, SAS Nagar, PO Manauli, Punjab, 140306, India.

ABSTRACT

Background: In Drosophila melanogaster the fitness of males depends on a broad array of reproductive traits classified as pre- and post-copulatory traits. Exposure to cold stress, can reduce sperm number, male mating ability and courtship behavior. Therefore, it is expected that the adaptation to cold stress will involve changes in pre- and post-copulatory traits. Such evolution of reproductive traits in response to cold stress is not well studied.

Methods: We selected replicate populations of D. melanogaster for resistance to cold shock. Over 37-46 generations of selection, we investigated pre- and post-copulatory traits such as mating latency, copulation duration, mating frequency, male fertility, fitness (progeny production) and sperm competitive ability in male flies subjected to cold shock and those not subjected to cold shock.

Results: We found that post cold shock, the males from the selected populations had a significantly lower mating latency along with, higher mating frequency, fertility, sperm competitive ability and number of progeny relative to the control populations.

Conclusion: While most studies of experimental evolution of cold stress resistance have documented the evolution of survivorship in response to selection, our study clearly shows that adaptation to cold stress involves rapid changes in the pre- and post-copulatory traits. Additionally, improved performances under stressful conditions need not necessarily trade-off with performance under benign conditions.

No MeSH data available.


Related in: MedlinePlus

Effect of cold shock on sperm offense ability (P2).Closed bars represent the FCB and open bars represent the FSB populations. Since the females and competitors males have recessive scarlet eye marker and the FSB and FCB males have dominant red eye marker, progeny sired by FSB and FCB males will show red eye color. Hence, in this experiment, the proportion of red eyed progeny is an indicator of sperm offense ability. (A) These data come from females that produced at least one progeny from the FSB or FCB male (that is non-zero sperm offense ability). Compared to FCB males, FSB males had higher sperm offense ability under cold shocked and non-shocked conditions. Selection and treatment had significant effect on P2. However, selection × treatment interaction was not significant. (B) Proportion of males that had zero-sperm offense ability (P2). Significantly lesser proportion of FSB males had zero sperm offense compared to FCB males. Selection and treatment effects were significant. However, selection × treatment interaction was not significant.
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pone.0153629.g006: Effect of cold shock on sperm offense ability (P2).Closed bars represent the FCB and open bars represent the FSB populations. Since the females and competitors males have recessive scarlet eye marker and the FSB and FCB males have dominant red eye marker, progeny sired by FSB and FCB males will show red eye color. Hence, in this experiment, the proportion of red eyed progeny is an indicator of sperm offense ability. (A) These data come from females that produced at least one progeny from the FSB or FCB male (that is non-zero sperm offense ability). Compared to FCB males, FSB males had higher sperm offense ability under cold shocked and non-shocked conditions. Selection and treatment had significant effect on P2. However, selection × treatment interaction was not significant. (B) Proportion of males that had zero-sperm offense ability (P2). Significantly lesser proportion of FSB males had zero sperm offense compared to FCB males. Selection and treatment effects were significant. However, selection × treatment interaction was not significant.

Mentions: We found a significant effect of selection and treatment on sperm offense ability. Post cold shock, FSB males sired 12% more progeny compared to FCB males (Fig 6A). Without cold shock, FSB males sired 4% more progeny relative to FCB males, although this difference was not significant (Fig 6A). In both FSB and FCB populations cold shocked males had lower sperm offense ability (P2) compared to non shocked males. None of interactions were significant (Table 6A).


Evolution of Pre- and Post-Copulatory Traits in Male Drosophila melanogaster as a Correlated Response to Selection for Resistance to Cold Stress.

Singh K, Samant MA, Tom MT, Prasad NG - PLoS ONE (2016)

Effect of cold shock on sperm offense ability (P2).Closed bars represent the FCB and open bars represent the FSB populations. Since the females and competitors males have recessive scarlet eye marker and the FSB and FCB males have dominant red eye marker, progeny sired by FSB and FCB males will show red eye color. Hence, in this experiment, the proportion of red eyed progeny is an indicator of sperm offense ability. (A) These data come from females that produced at least one progeny from the FSB or FCB male (that is non-zero sperm offense ability). Compared to FCB males, FSB males had higher sperm offense ability under cold shocked and non-shocked conditions. Selection and treatment had significant effect on P2. However, selection × treatment interaction was not significant. (B) Proportion of males that had zero-sperm offense ability (P2). Significantly lesser proportion of FSB males had zero sperm offense compared to FCB males. Selection and treatment effects were significant. However, selection × treatment interaction was not significant.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4836659&req=5

pone.0153629.g006: Effect of cold shock on sperm offense ability (P2).Closed bars represent the FCB and open bars represent the FSB populations. Since the females and competitors males have recessive scarlet eye marker and the FSB and FCB males have dominant red eye marker, progeny sired by FSB and FCB males will show red eye color. Hence, in this experiment, the proportion of red eyed progeny is an indicator of sperm offense ability. (A) These data come from females that produced at least one progeny from the FSB or FCB male (that is non-zero sperm offense ability). Compared to FCB males, FSB males had higher sperm offense ability under cold shocked and non-shocked conditions. Selection and treatment had significant effect on P2. However, selection × treatment interaction was not significant. (B) Proportion of males that had zero-sperm offense ability (P2). Significantly lesser proportion of FSB males had zero sperm offense compared to FCB males. Selection and treatment effects were significant. However, selection × treatment interaction was not significant.
Mentions: We found a significant effect of selection and treatment on sperm offense ability. Post cold shock, FSB males sired 12% more progeny compared to FCB males (Fig 6A). Without cold shock, FSB males sired 4% more progeny relative to FCB males, although this difference was not significant (Fig 6A). In both FSB and FCB populations cold shocked males had lower sperm offense ability (P2) compared to non shocked males. None of interactions were significant (Table 6A).

Bottom Line: In Drosophila melanogaster the fitness of males depends on a broad array of reproductive traits classified as pre- and post-copulatory traits.Exposure to cold stress, can reduce sperm number, male mating ability and courtship behavior.Additionally, improved performances under stressful conditions need not necessarily trade-off with performance under benign conditions.

View Article: PubMed Central - PubMed

Affiliation: Indian Institute of Science Education and Research Mohali, Knowledge City, Sector 81, SAS Nagar, PO Manauli, Punjab, 140306, India.

ABSTRACT

Background: In Drosophila melanogaster the fitness of males depends on a broad array of reproductive traits classified as pre- and post-copulatory traits. Exposure to cold stress, can reduce sperm number, male mating ability and courtship behavior. Therefore, it is expected that the adaptation to cold stress will involve changes in pre- and post-copulatory traits. Such evolution of reproductive traits in response to cold stress is not well studied.

Methods: We selected replicate populations of D. melanogaster for resistance to cold shock. Over 37-46 generations of selection, we investigated pre- and post-copulatory traits such as mating latency, copulation duration, mating frequency, male fertility, fitness (progeny production) and sperm competitive ability in male flies subjected to cold shock and those not subjected to cold shock.

Results: We found that post cold shock, the males from the selected populations had a significantly lower mating latency along with, higher mating frequency, fertility, sperm competitive ability and number of progeny relative to the control populations.

Conclusion: While most studies of experimental evolution of cold stress resistance have documented the evolution of survivorship in response to selection, our study clearly shows that adaptation to cold stress involves rapid changes in the pre- and post-copulatory traits. Additionally, improved performances under stressful conditions need not necessarily trade-off with performance under benign conditions.

No MeSH data available.


Related in: MedlinePlus