![Dr Russell Arnott on Twitter: "As well as having the largest penis-to-body length ratio on Earth, DYK the barnacle also has testicles on its head? 🏔️🍆 #HeadBallsDay #EdBallsDay https://t.co/nOWoqSJKEI" / Twitter Dr Russell Arnott on Twitter: "As well as having the largest penis-to-body length ratio on Earth, DYK the barnacle also has testicles on its head? 🏔️🍆 #HeadBallsDay #EdBallsDay https://t.co/nOWoqSJKEI" / Twitter](https://pbs.twimg.com/media/E0Dpav-WUAIyqMV.png)
Dr Russell Arnott on Twitter: "As well as having the largest penis-to-body length ratio on Earth, DYK the barnacle also has testicles on its head? 🏔️🍆 #HeadBallsDay #EdBallsDay https://t.co/nOWoqSJKEI" / Twitter
Fun fact: A tapir has the largest penis-to-body ratio of any animal. - Post by UserOne on Boldomatic
![TIL the Argentine Lake Duck has the longest penis to body ratio of any vertebrate. The 8 inch duck has a 17 inch penis. If humans had this ratio, the human penis TIL the Argentine Lake Duck has the longest penis to body ratio of any vertebrate. The 8 inch duck has a 17 inch penis. If humans had this ratio, the human penis](https://external-preview.redd.it/QcH16CCDrL42F5zPBEulJ7nsZKchjrzfhIYx_mcxKUs.jpg?auto=webp&s=bfc1296776476195fa8cc5d170c970078495d4f7)