trait is expressed in males12. Similarly, if male tail length differs among bird populations, females could have a preference for long tails that varies in accordance with the expression of the male trait. But female preferences may not simply be for males with the longest tails; rather, they may be for males with fast-growing ornaments, or for males that can maintain the ornaments over a perio...

Species spanning the animal kingdom have evolved extravagant and costly ornaments to attract mating partners. Zahavi's handicap principle offers an elegant explanation for this: ornaments signal individual quality, and must be costly to ensure honest signalling, making mate selection more efficient. Here, we incorporate the assumptions of the handicap principle into a mathematical model and sho...

In the attempt to understand culture and social behavior of prehistoric populations, findings of personal ornaments are of particular interest. Personal ornaments in their formal expressions (marine shells and snails, river snails, animal teeth, modified animal bones etc.) not only point to an universal idea of decoration and aesthetic sensibility, but may also reveal contact zones and communic...

A score-following algorithm for polyphonic MIDI performances is presented that can handle performance mistakes, ornaments, desynchronized voices, arbitrary repeats and skips. The algorithm is derived from a stochastic performance model based on hidden Markov model (HMM), and we review the recent development of model construction. In this paper, the model is further extended to capture the multi...

Sexual selection and social selection are two important theories proposed for explaining the evolution of colorful ornamental traits in animals. Understanding signal honesty requires studying how environmental and physiological factors during development influence the showy nature of sexual and social ornaments. We experimentally manipulated physiological stress and immunity status during the m...

Oxidative stress could be a key selective force shaping the expression of colored traits produced by the primary animal pigments in integuments: carotenoids and melanins. However, the impact of oxidative stress on melanic ornaments has only recently been explored, whereas its role in the expression of carotenoid-based traits is not fully understood. An interesting study case is that of those an...

The phenotype-linked fertility hypothesis proposes that male ornaments reflect male fertility. Male ornaments could honestly signal sperm quality due to the high susceptibility of sperm to free radicals on the one hand and the negative impact of oxidative stress on ornament elaboration on the other hand. Thus, only males with superior antioxidant defenses could bear the cost of more elaborated ...