The examples and perspective in this article deal primarily with the United States and do not represent a worldwide view of the subject. (December 2010) (Learn how and when to remove this template message)
Tongue bifurcation, splitting or forking, is a type of body modification in which the tongue is cut centrally from its tip to as far back as the underside base, forking the end. It is a common body alteration for body modification enthusiasts.
There are several methods used to split tongues: cutting with a scalpel, cauterizing and tying off. It is performed by oral surgeons, plastic surgeons, or body modification practitioners, or done oneself, but only oral and plastic surgeons are licensed. Before splitting with any method, some choose to have a well-healed tongue piercing where the back end of the split is intended to be. This effectively prevents the tongue from healing forward from the back of the cut, which would result in a split that is not as deep as desired.
When using the scalpel method, the tongue is cut down the middle with a scalpel and each half is stitched or sutured along the cut edge. This helps prevent the sides from healing back to each other and also achieves a more rounded and natural look. In some cases the scalpel is heated to provide a cauterizing effect, limiting bleeding.
Cauterizing can be done with a cautery unit or an argon laser. Both burn the tongue in half which closes off blood vessels, preventing much bleeding. If an established tongue piercing is not used as the back end of the split with this method, the tongue has a higher tendency to heal and the procedure must be done again to achieve the depth desired.
The tie off or fishing line method is done by the person themselves. Fishing line is tied through an existing tongue piercing to the tip of the tongue and tightened. When the line has cinched through the tissue and become loose, it is cut out and a new tighter line is placed in to continue the cut. This slower process allows the tongue to heal as it is being split, negating the need for stitches or cauterization to control bleeding as blood loss is limited. It can take anywhere from a few days to a few months to split the tongue this way depending on the individual's pain tolerance and determination.
The tongue generally heals in 1–2 weeks, during which time the person may have difficulty with speech or their normal dietary habits. Splitting is reversible but the reversal is even more painful than the tongue splitting procedure.
After the tongue is split and the sides healed, control over the individual sides can be gained with practice. The two halves can be raised up and down opposite each other, spread apart from the other half which makes the split quite apparent and some objects can be grasped onto and held. A split tongue is an easy body modification to conceal with a little effort. Keeping the tongue in the mouth and the two halves pressed together when speaking can keep the split out of view. When the two sides are held together, it appears as though there is only a deep crevice in the center of the tongue.
Many cite increased sensation, enhancement when kissing for the giver and receiver or novelty, but the reasons can be deeper as well. Challenging oneself, rites of passage, connecting with or being in control of one's body, making a spiritual connection or testing the body's limits are also reasons given. Like all body modifications, it can be used to connect or identify with a specific group or to ward off those who would make quick undesired judgments based on appearance.
Dustin Allor, a 19-year-old body piercer in the U.S., split her tongue in 1996 herself. Not having any reference of this being done before, she came up with the tie-off or fishing line method. In 1997 she was featured on the cover of Fakir Musafar's Body Play Magazine. Dustin's documented success with this process inspired coworker Natalie Lowry to follow suit in 2001.
Erik Sprague, aka The Lizardman had his tongue split on July 18, 1997, by oral surgeon Dr. Lawrence Busino, using an argon laser. A new deeper split was done on October 3, 1997. This was the third modern tongue bifurcation and the first one done using a laser.
The legality of tongue splitting varies greatly depending on the country and within those countries, individual states or territories. Some examples are given below, but do not encompass all the laws regarding this subject.
Some branches of the U.S. military ban body modifications that detract from a professional military image and explicitly include tongue splitting or forking as examples.
In 2003, Illinois became the first state in the U.S. to regulate tongue splitting, passing a law making it illegal to perform the procedure on another person, unless it is done by someone licensed to practice medicine. The law does not appear to prohibit performing the procedure on one's self.  Since then New York, Delaware, and Texas have enacted laws that either ban the practice, ban the procedure on minors without parental consent, or restrict it to being performed by only doctors and/or dentists.
In 2009, the Australian state of Victoria enacted a ban on splitting the tongues of minors.
In 2017 Brendan McCarthy was prosecuted in the United Kingdom for a number of body modifications including tongue splitting. The charge was causing grievous bodily harm with intent, with an alternative charge of wounding without intent. 
- "Tongue Splitting". Ishiboo.com. Retrieved 2015-03-08.
- "Archived copy". Archived from the original on April 18, 2005. Retrieved January 12, 2010.
-  Archived June 3, 2009, at the Wayback Machine.
- "Tongue Splitting More Than Budding Controversy on". Ethicsdaily.com. 2003-05-29. Archived from the original on 2015-03-08. Retrieved 2015-03-08.
- "Body Play Issue Number 16". Bodyplay.com. Retrieved 2015-03-08.
- [dead link]
- "Military Law Review" (PDF). Loc.gov. Retrieved 2015-03-08.
- "720 ILCS 5/12-10.2". Archived from the original on 2015-04-02. Retrieved 2015-04-01.
- "Lawcrawler - FindLaw". Lawcrawler.findlaw.com. Retrieved 2015-03-08.
-  Archived November 27, 2010, at the Wayback Machine.