Referee 1's Review:

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N.B. These are the comments made by the referee when reviewing an earlier version of this paper. Prior to publication, the manuscript has been revised in light of these comments and to address other editorial requirements.
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Bedhomme et al examine the reproductive behaviour of lines of flies in which the genomes have been male limited. Previous work showed that the males from these ML lines evolved higher competitive fitness than controls and females from the ML lines displayed lower competitive fitness. Here the authors show that ML males display less courtship and that ML females appear to be less attractive and do less yeast feeding. The rationale for looking at this is sensible, the male results are unexpected, the experiments adequately performed and in general the data should be published. However the ms in its current form is not acceptable, for two main reasons.

1) The readers need to see more of the data. Often mating/ feeding data is shown in table format and this would be very useful here. Let's see the actual numbers of courtship and mating events at each time point. There isn't an awful lot of data so this should be possible - or if it is unwieldy, put it in an appendix or something like that. Then the reader can make up their own mind about how to interpret the data and what it might or might not mean.

2) The interpretation of the results in the ms is flawed and really tries to peddle something more exciting than the data show. The data do not show increased courtship efficiency - they just show less courtship. The increased courtship efficiency argument relies on the assumption that females mate more when they are courted more and this is not known. Some evidence suggests that females mate when they want and that the amount they are courted is irrelevant. For example, mating rate does not increase with increased density even though encounter rate does. To show increased courtship efficiency you would have to compete the ML and C males against a standard competitor male and show that the ML males gain significantly more matings per courtship. When there are no competitor males you can't conclude this. And for the reduced feeding in the ML females - the emerging data suggest that feeding behaviour is driven by egg production (when food is abundant at least) rather than the other way round. This is mentioned in the abstract but largely ignored elsewhere in the ms.

In conclusion, the authors should a) show as much of the raw data as practically possible and b) cut down on all the speculation of what the results might mean - just state some facts.