Healthy serenades

Female songbirds like males with wide range of songs

source: New Scientist February 6 2000 p25

Female songbirds tend to prefer males which have wide repertoires. The mortality rate for reed warbler chicks is lower for those with fathers with extensive repertoires. Anders Moller heads a team from the Pierre and Marie Curie University, Paris, France, which has examined 38 songbird species. They have found that songbirds' spleen sizes are linked to the sizes of their repertoires. Spleen sizes are also an indication of the condition of immune systems.
BI,BR