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Inbreeding depression has been hypothesized to drive the evolution of mating systems and dispersal. Some studies have shown that inbreeding strongly affects survival and/or fecundity, but other studies suggest that fitness consequences of inbreeding are less detrimental or more complex. We studied consequences of mating with a relative in a population of great tits (Parus major) with a high local recruitment rate. Genotypic information from microsatellite markers was used to calculate coefficients of kinship, and fitness was measured as seasonal and lifetime reproductive success. We show that mating with a relative affects seasonal reproductive success, as was found in other studies of the same species. However, these effects do not result in a lifetime fitness reduction, suggesting that individuals may have scope for avoidance of inbreeding after inbreeding depression. Several explanations are proposed as compensatory mechanisms. Although individuals are more likely to divorce after experiencing inbreeding depression, we show that divorce alone cannot explain the compensation for inbreeding depression in subsequent breeding attempts in our study. We conclude that the costs of mating with a relative in the short term do not necessarily imply lifetime fitness consequences. [ABSTRACT FROM AUTHOR]

It is an established fact that the spectacular bioluminescent displays of adult fireflies and glow-worms are used as courtship signals; however, the survival value of the glowing behavior of their larvae remained the subject of speculation for many years. Our study is the first that demonstrates that lampyrid larvae use luminescence to signal unpalatability to nocturnal, visually guided predators. Wild-caught toads (Bufo bufo) were more reluctant to attack luminescent artificial prey, and we show that avoidance learning increased this reluctance. After being exposed to glow-worm larvae (Lampyris noctiluca), which the toads experienced as disagreeable, attack latencies to luminescent prey increased, but not those to nonglowing prey. Not all toads showed avoidance learning to the same extent, because of either differences in previous experience with glow-worms or differences in memory. [ABSTRACT FROM AUTHOR]