Birdsong is an important signal used in intra- and intersexual communication a reproductive context. Strong sexual natural selective forces act on this behaviour, such that singing individuals can be viewed as vocal athletes whose performance critical for success. In review, I argue illustrate how solid understanding of song production mechanisms enhance our investigations performance. From per...

In order to achieve the objectives of research, building a measure management by according (sigma six) methodology for athletics sub-associations from players' point view, researchers had take necessary procedures and measures this matter. This was done them through use descriptive approach defining research community with specificity (100) advanced players athletics. As scientific contexts wer...