"Bestiosexuality" was discussed briefly by Allen (1979), but never became widely established.Ernest Bornemann (1990, cited by Rosenbauer, 1997) coined the separate term zoosadism for those who derive pleasure – sexual or otherwise – from inflicting pain on animals.Data scientists from New York-based dating app, Hinge, analysed their members' photos to reveal which profile pictures get the most likes.

The results varied between men and women, especially when it came to the style of smiling, and which direction to look in.

Women were found to be more successful when smiling with their teeth and looking away from the camera.

Anyone with an online dating account will know that choosing the perfect profile picture for your page is a tricky business.

From candid photos to Snapchat selfies, it can be difficult to know what will help you bag the likes in a sea of profiles.

And while you might see them as old-fashioned, black and white photos were a huge hit, increasing likes by a huge 106 per cent.

Hinge also discovered that spontaneous snaps were more likely to get a like than posed photos.

The terms are often used interchangeably, but some researchers make a distinction between the attraction (zoophilia) and the act (bestiality).

Three key terms commonly used in regards to the subject — zoophilia, bestiality, and zoosexuality — are often used somewhat interchangeably.

Zoophilia is a paraphilia involving a sexual fixation on non-human animals.