Gelada (Theropithecus gelada): family male and estruc female have bright chest patch
Bachelor Elvis challenges Chewbacca
Sage-grouse on lek, with fembot
Barn swallow do not really pair bond. Female choose feather color
Gelada on sleeping cliffs; red chest patches release heat in cold - handicap principle, honest assessment
Southern Elephant Seal
Pheromones
African Saturniid Butterflies: upper eyespots reflect UV
Gelada chest patches correlated with hormone levels
Peter Chen 2.0