Male and female mate choice affects offspring quality in a sex-role-reversed pipefish

Where both sexes invest substantially in offspring, both females and males should discriminate between potential partners when choosing mates. The deg ree of choosiness should relate to the costs of choice and to the potential benefits to be gained. We measured offspring quality from experimentally s taged matings with preferred and non-preferred partners in a sex-role-rever sed pipefish, Syngnathus typhle L. Here, a substantial male investment in o ffspring results in a lower potential reproductive rate in males than in fe males, and access to males limits female reproductive success rather than v ice versa. Thus, males are choosier than females and females compete more i ntensely? over mates than do males. Broods from preferred matings were supe rior at escaping predation, when either males or females were allowed to ch oose a partner. However, only 'choosing' females benefited in terns of fast er-growing offspring. Our results have important implications for mate-choi ce research: here we show that even the more competitive and less choosy se x may contribute significantly to sexual selection through mate choice.