Alternative reproductive tactics in male common shrews: relationships between mate-searching behaviour, sperm production, and reproductive success as revealed by DNA fingerprinting

AbstractMale rhesus macaques on Cayo Santiago use rank-dependent alternative reproductive tactics. High-ranking males can form long-term consorts and guard female mates while low-ranking males frequently resort to quick copulations under the cover of vegetation. No single reproductive tactic provided the Group S males with a definitive reproductive advantage during the one-year study. Males using the long-term tactic and the quick, stealth tactic sired five offspring each, but fewer males used the long-term consort tactic. Males using the long-term reproductive tactic have significantly greater mating success than males using the quick, sneaky tactic, and may have greater reproductive success. The highest-ranking males who form long-term consorts had the greatest degree of reproductive success. This indicates that for the highest-ranking males, forming long-term consorts is the most effective reproductive tactic. The effectiveness of alternative tactics for high-ranking males (i.e. consort disruption and possessive following) was equivocal. Consort disruption had no immediate effect on reproductive success. Possessive following may have resulted in the siring of two offspring by the alpha male, but was ineffective in other cases, where the females were inseminated by subordinate males. The effectiveness of the quick, furtive tactic was demonstrated by the siring of 45% of the infants by males who used this tactic.

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DIFFERENTIAL REPRODUCTIVE SUCCESS AND HERITABILITY OF ALTERNATIVE REPRODUCTIVE TACTICS IN WILD ATLANTIC SALMON (SALMO SALAR L)

Evolution ◽

10.1554/0014-3820(2003)057[1133:drsaho]2.0.co;2 ◽

2003 ◽

Vol 57 (5) ◽

pp. 1133 ◽

Cited By ~ 8

Author(s):

Dany Garant ◽

Julian J. Dodson ◽

Louis Bernatchez

Keyword(s):

Reproductive Success ◽

Atlantic Salmon ◽

Salmo Salar ◽

Alternative Reproductive Tactics ◽

Reproductive Tactics ◽

Atlantic Salmon Salmo Salar ◽

Differential Reproductive Success

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Subordinate male meerkats prospect for extra-group paternity: alternative reproductive tactics in a cooperative mammal

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2007.0316 ◽

2007 ◽

Vol 274 (1618) ◽

pp. 1603-1609 ◽

Cited By ~ 86

Author(s):

Andrew J Young ◽

Goran Spong ◽

Tim Clutton-Brock

Keyword(s):

Reproductive Success ◽

Alternative Reproductive Tactics ◽

Substantial Proportion ◽

Reproductive Tactics ◽

Age At First Reproduction ◽

Suricata Suricatta ◽

Cooperatively Breeding ◽

First Reproduction ◽

Fitness Benefits ◽

Animal Societies

In cooperatively breeding species, subordinates typically suffer strong constraints on within-group reproduction. While numerous studies have highlighted the additional fitness benefits that subordinates might accrue through helping, few have considered the possibility that subordinates may also seek extra-group matings to improve their chances of actually breeding. Here, we show that subordinate males in cooperative meerkat, Suricata suricatta , societies conduct frequent extraterritorial forays, during periods of peak female fertility, which give rise to matings with females in other groups. Genetic analyses reveal that extra-group paternity (EGP) accrued while prospecting contributes substantially to the reproductive success of subordinates: yielding the majority of their offspring (approx. 70%); significantly reducing their age at first reproduction and allowing them to breed without dispersing. We estimate that prospecting subordinates sire 20–25% of all young in the population. While recent studies on cooperative birds indicate that dominant males accrue the majority of EGP, our findings reveal that EGP can also arise from alternative reproductive tactics employed exclusively by subordinates. It is important, therefore, that future attempts to estimate the fitness of subordinate males in animal societies quantify the distribution of extra-group as well as within-group paternity, because a substantial proportion of the reproductive success of subordinates may otherwise go undetected.

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Sex differences in alternative reproductive tactics in response to predation risk in tree crickets

10.1101/848630 ◽

2019 ◽

Author(s):

Viraj R. Torsekar ◽

Rohini Balakrishnan

Keyword(s):

Predation Risk ◽

Mating Success ◽

Empirical Studies ◽

Search Strategies ◽

Negative Effects ◽

Reproductive Tactics ◽

Mate Searching ◽

Searching Behaviour ◽

Mate Search

AbstractPredation risk has been hypothesised to drive the evolution of alternative mate-search strategies, but few empirical studies have examined this. In crickets, mate-search involves acoustic signalling by males and acoustic-mediated movement by females. It is unclear whether predators affect fitness of both sexes directly, by reducing survival, or indirectly, by affecting mate-searching. We empirically examined effects of increased predation risk on mate-searching behaviour and survival of male and female tree crickets, and their effects on mating success, using field-enclosure experiments with tree crickets Oecanthus henryi and their primary predator, green lynx spiders, Peucetia viridans. Crickets were allocated into three treatments with differential levels of predation risk. Increased predation risk strongly reduced survival, and thereby mating success, for both sexes. With increasing predation risk, males reduced calling and increased movement towards neighbouring callers, which had negative effects on mating success. Using simulations, we found male movement was significantly directed towards other calling males implying a switch to satellite strategies. Female movement behaviour, however, remained unaltered. Males and females thus differed in their response to comparable levels of predation risk, showing that the role of predation as a driver of alternative mate search strategies is sex and strategy-specific.

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