teams flourished in the professional era others such as Richmond, Wakefield, Orrell, Waterloo and London Scottish found the going much harder and have either folded or dropped down to minor leagues. In the other Home Nations, Ireland, Scotland and Wales, the professional era had a traumatic effect on the traditional structure of the sport, which had been based around local clubs. Professional rugby in these three countries is now regionally based. In Ireland, each of the four traditional provinces supports one professional team. Scotland currently has two regional teams, each based in one of the country's two largest cities. Wales adopted a regional franchise model, originally with five teams but now with four. These three countries have a joint professional competition, originally known as the Celtic League. In 2010, two Italian super-regional teams joined the competition, which was renamed the Pro12, and in 2017, two South African franchises joined the Pro14 competition. This eventually became the United Rugby Championship, with four different South African teams. 21st century Alterations to the laws of rugby union were trialled by students of Stellenbosch University in South Africa in 2006, and were adopted in competitions in Scotland and Australia since 2007, though only a few of the rules were universally adopted. The law variations are an attempt to make rugby union easier to understand by referees, fans and players, but the laws were controversial and far from being endorsed by all members of these groups. After a number of trials around half of the proposed changes were permanently added to the laws of the sport. In 2012, the Tri Nations was expanded to include Argentina, with the competition being renamed The Rugby Championship. The competition's organiser, now known as SANZAAR after the Argentine Rugby Union became a full member in 2016, has also expanded Super Rugby in the 21st century, first expanding from 12 to 14 teams in 2006, then to 15 teams in 2011, and most recently to 18 teams in 2016. The last of these expansions spread Super Rugby's geographic scope outside of its founding countries (South Africa, Australia, New Zealand) for the first time, adding new teams in Argentina and Japan. In 2014, the European club competition structure was revamped. The top-level Heineken Cup and second-level European Challenge Cup were respectively replaced by the European Rugby Champions Cup and European Rugby Challenge Cup. The most significant changes to the structure were