Wicca, a "tradition" usually implied the transfer of a lineage by initiation. However, with the rise of more and more such groups, often being founded by those with no previous initiatory lineage, the term came to be a synonym for a religious denomination within Wicca. There are many such traditions and there are also many solitary practitioners who do not align themselves with any particular lineage, working alone. Some covens have formed but who do not follow any particular tradition, instead choosing their influences and practices eclectically. Those traditions which trace a line of initiatory descent back to Gerald Gardner include Gardnerian Wicca, Alexandrian Wicca and the Algard tradition; because of their joint history, they are often referred to as British Traditional Wicca, particularly in North America. Other traditions trace their origins to different figures, even if their beliefs and practices have been influenced to a greater or lesser extent by Gardner. These include Cochrane's Craft and the 1734 Tradition, both of which trace their origins to Robert Cochrane; Feri, which traces itself back to Victor Anderson and Gwydion Pendderwen; and Dianic Wicca, whose followers often trace their influences back to Zsuzsanna Budapest. Some of these groups prefer to refer to themselves as Witches, thereby distinguishing themselves from the BTW traditions, who more typically use the term Wiccan (see Etymology). During the 1980s, Viviane Crowley, an initiate of both the Gardnerian and Alexandrian traditions, merged the two. Pearson noted that "Wicca has evolved and, at times, mutated quite dramatically into completely different forms". Wicca has also been "customized" to the various national contexts into which it has been introduced; for instance, in Ireland, the veneration of ancient Irish deities has been incorporated into Wicca. Covens Lineaged Wicca is organised into covens of initiated priests and priestesses. Covens are autonomous and are generally headed by a High Priest and a High Priestess working in partnership, being a couple who have each been through their first, second, and third degrees of initiation. Occasionally the leaders of a coven are only second-degree initiates, in which case they come under the rule of the parent coven. Initiation and training of new priesthood is most often performed within a coven environment, but this is not a necessity, and a few initiated Wiccans are unaffiliated with any coven. Most covens would not admit members under the age of 18. They often do not advertise their existence,