(Downloading may take up to 30 seconds.
If the slide opens in your browser, select File -> Save As to save it.)
Click on image to view larger version.



Fig. 5. Effective wingbeat frequency with respect to flight angle for two barn swallows (open symbols), two house martins (filled symbols) and one unidentified hirundine (black crosses) for continuous flight intervals of 20 s. Lines connect consecutive 20 s intervals of an individual flight path.