A stimulatory phalloid organ in a weaver bird | Nature
Why birds don't have penises and how it could offer clues to help understand human disorders | Daily Mail Online
Ornithologist Richard Prum on Duck Sex and Human Evolution - DER SPIEGEL
Monday Links: Birds with Human Penises
Mystery of the male ostrich's erection solved | New Scientist
Bird Penis Genital Mandarin Duck Stock Photo 1362199346 | Shutterstock
How Do Birds Mate? (Everything Explained) | Birdfact
How Birds Mate | Bird Sex & Reproduction | Bird Spot
Creature Courtship | Chicago News | WTTW
Ostrich penis Stock Photo by ©Kantapat 13803511
harvesting the fruits of the web — liartownusa: Birds with Human Penises 2014...
Do Birds Have Penises? – 10,000 Birds
Ostrich penis clears up evolutionary mystery | Nature
Lake duck - Wikipedia
White-headed Duck (Oxyura leucocephala) adult male, biting extended penis after mating, on water (captive) - SuperStock
Why are duck penises corkscrew-shaped and how do they mate? | BBC Science Focus Magazine
Found! The longest bird penis ever › News in Science (ABC Science)
Why are duck penises corkscrew-shaped and how do they mate? | BBC Science Focus Magazine
Do Birds Have Penises? – 10,000 Birds
Scientists Discover the Genetic Reason Why Birds Don't Have Penises | Science| Smithsonian Magazine
Duck Penises Grow Bigger Among Rivals
Sex and the Birds: 1. Copulation – Bird Ecology Study Group
Evolution: One Penis After All - ScienceDirect
Evidence of phenotypic plasticity of penis morphology and delayed reproductive maturation in response to male competition in waterfowl
File:Birds on winged penis detail, Discourse on the worship of Priapus and its connection with the mystic theology of the ancients 4 figs (cropped).jpg - Wikimedia Commons
