Kissing is not unique to humans, and many animals also convey love in this way. The blue-footed booby is a large tropical seabird, and when they kiss, they are more devoted and more pure. (Image from Oriental IC)
These two marmots, kissing, looked like a fight. (Image from Oriental IC)
These two, called cacti ground finches, are also too bold in broad daylight. (Image from Oriental IC)
Looking at the way these two partridges were engaged, I really couldn't bear to disturb them. (Image from Oriental IC)
Two double gannets openly kissed in front of their companions, and it seemed that they were a pair of old "jianghu". (Image from Oriental IC)
This is the Australasia gannet, with blue eyes, heartbreakingly beautiful. (Please click on the red "Follow" above the image to see the picture together.) (Image from Oriental IC)