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Although many studies have investigated the occurrence of extra-pair paternity (EPP) and its adaptive significance in wild population of birds, we still know surprising little about the plasticity in mating behavior of females at the individual level and how it affects the patterns of paternity. To address this question, we focused on the direct fertility benefit hypothesis for the function of EPP and studied if female birds react in extra-pair mating behavior after reproductive failures using a wild population of the Japanese great tit, Parus minor, a socially monogamous passerine with a moderate frequency of EPP and a high-multiple brooding rate. We simulated hatching failure by replacing with artificial eggs during the egg laying period to investigate whether females subsequently altered their mating behavior and became more promiscuous to improve reproductive success in their following clutches. The proportion of extra-pair offspring per clutches of both experimental and control pairs increased in the second clutches (replacement and repeat), but compared with the control pairs, the increase in the experimental pairs was significantly greater. The present study suggests that individual females appear to be making decisions based on specific cues and flexibly altering mating behavior in adaptive ways. Also, our results are compatible with one of the long-debated hypotheses for the evolutionary maintenance of EPP which predicts that females gain direct fitness benefit through increased reproductive success from mating multiply. [ABSTRACT FROM AUTHOR]

We present a kinematic study of the sub-parsec-scale radio jet of the radio galaxy 3C 84/NGC 1275 with the VLBI Exploration of Radio Astrometry (VERA) array at 22 GHz for 80 epochs from 2007 October to 2013 December. The averaged radial velocity of the bright component "C3" with reference to the radio core is found to be 0.27 ± 0.02  c between 2007 October and 2013 December. This constant velocity of C3 is naturally explained by the advancing motion of the head of the mini-radio lobe. We also find a non-linear component in the motion of C3 with respect to the radio core. We briefly discuss possible origins of this non-linear motion. [ABSTRACT FROM AUTHOR]