Adaptive individual variation in phenological responses to perceived predation levels

The adaptive evolution of timing of breeding (a component of phenology) in response to environmental change requires individual variation in phenotypic plasticity for selection to act upon. A major question is what processes generate this variation. Here we apply multi-year manipulations of perceived predation levels (PPL) in an avian predator-prey system, identifying phenotypic plasticity in phenology as a key component of alternative behavioral strategies with equal fitness payoffs. We show that under low-PPL, faster (versus slower) exploring birds breed late (versus early);the pattern is reversed under high-PPL, with breeding synchrony decreasing in conjunction. Timing of breeding affects reproductive success, yet behavioral types have equal fitness. The existence of alternative behavioral strategies thus explains variation in phenology and plasticity in reproductive behavior, which has implications for evolution in response to anthropogenic change

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Broadband Video Streaming with Built-In Resiliency

Mobile TV services are being actively developed for a variety of last hop, broadband wireless technologies. Application layer error control mechanisms such as Broadband Video Streaming seek to reduce packet loss from raw UDP transport. This paper goes further than existing streaming protocols by integrating source-coded error resilience through data-partitioning and intra-refresh macroblocks with the error control mechanism. Results show that for a temporally complex sequence, up to 6.23 dB gain in video quality (PSNR) can result, depending on burst error lengths across an IEEE 802.16e link