Background: Thor Heyerdahl (Norwegian pronunciation: [tu:r 'haei@da:l]; October 6, 1914 - April 18, 2002) was a Norwegian adventurer and ethnographer with a background in zoology, botany, and geography. He became notable for his Kon-Tiki expedition in 1947, in which he sailed 8,000 km (5,000 mi) across the Pacific Ocean in a hand-built raft from South America to the Tuamotu Islands. The expedition was designed to demonstrate that ancient people could have made long sea voyages, creating contacts between separate cultures. This was linked to a diffusionist model of cultural development.
Context: In 1955-1956, Heyerdahl organized the Norwegian Archaeological Expedition to Rapa Nui (Easter Island). The expedition's scientific staff included Arne Skjolsvold, Carlyle Smith, Edwin Ferdon, Gonzalo Figueroa and William Mulloy. Heyerdahl and the professional archaeologists who travelled with him spent several months on Rapa Nui investigating several important archaeological sites. Highlights of the project include experiments in the carving, transport and erection of the notable moai, as well as excavations at such prominent sites as Orongo and Poike. The expedition published two large volumes of scientific reports (Reports of the Norwegian Archaeological Expedition to Easter Island and the East Pacific) and Heyerdahl later added a third (The Art of Easter Island). Heyerdahl's popular book on the subject, Aku-Aku was another international best-seller.  In Easter Island: The Mystery Solved (Random House, 1989), Heyerdahl offered a more detailed theory of the island's history. Based on native testimony and archaeological research, he claimed the island was originally colonized by Hanau eepe ("Long Ears"), from South America, and that Polynesian Hanau momoko ("Short Ears") arrived only in the mid-16th century; they may have come independently or perhaps were imported as workers. According to Heyerdahl, something happened between Admiral Roggeveen's discovery of the island in 1722 and James Cook's visit in 1774; while Roggeveen encountered white, Indian, and Polynesian people living in relative harmony and prosperity, Cook encountered a much smaller population consisting mainly of Polynesians and living in privation.  Heyerdahl notes the oral tradition of an uprising of "Short Ears" against the ruling "Long Ears". The "Long Ears" dug a defensive moat on the eastern end of the island and filled it with kindling. During the uprising, Heyerdahl claimed, the "Long Ears" ignited their moat and retreated behind it, but the "Short Ears" found a way around it, came up from behind, and pushed all but two of the "Long Ears" into the fire. This moat was found by the Norwegian expedition and it was partly cut down into the rock. Layers of fire were revealed but no fragments of bodies.  As for the origin of the people of Easter Island, DNA tests have shown a connection to South America, critics conjecture that this was a result of recent events, but whether this is inherited from a person coming in later times is hard to know. If the story that (almost) all Long Ears were killed in a civil war is true, as the islanders story goes, it would be expected that the statue-building South American bloodline would have been nearly utterly destroyed, leaving for the most part the invading Polynesian bloodline.
Question: What year did they go?
Answer: In 1955-1956,

Problem: Background: Brotherhood of Man are a British pop group who achieved success in the 1970s. They won the 1976 Eurovision Song Contest with "Save Your Kisses for Me". Created in 1969 by songwriter and record producer Tony Hiller, Brotherhood of Man was initially an umbrella title for a frequently-changing line-up of session singers. Early on, they scored a worldwide hit with the song "United We Stand".
Context: Keen to keep the established name alive, Hiller set about putting a new line up together. In 1972 he got together a trio of session singers, Martin Lee, Nicky Stevens and Lee Sheriden.  Sheriden was already known to Hiller as a songwriter and had a solo career. Lee had a solo single to his name and was a budding songwriter. Stevens had been classically trained, but had since adapted her vocals and was performing as a cabaret singer. The trio began recording together, but their first single, "Rock Me Baby", to be released at the end of 1972, was cancelled due to the release of the song by David Cassidy. Finally their first two singles "Happy Ever After" and "Our World of Love" were released in 1973. Neither single charted and soon after, another female vocalist was added to the line up, Sandra Stevens. Stevens (no relation to Nicky) had been performing as a big-band singer since a teenager in the late 1960s. She had sung with the Joe Loss big band and alongside Eve Graham (of The New Seekers) in club group, The Nocturnes.  Now signed to the Pye spin off label, Dawn, the quartet released their first single, "When Love Catches Up on You" in January 1974. It failed to chart, but the follow-up single, "Lady" became a hit in Europe. Encouraged by this, the group set about recording their debut album. The album Good Things Happening was released later in the year along with two more singles, but none of these found success. Before the record label folded, Brotherhood of Man released one more single in the Summer of 1975. This was the upbeat "Kiss Me Kiss Your Baby" and although failed to make an impression in the UK, became a big hit in Europe, reaching Number one in Belgium and Number two in the Netherlands as well as top 10 placings in other countries. Brotherhood of Man toured extensively in Europe, honing their stage act and harmonies, while Hiller, Sheriden and Lee worked on composing songs for their second album. Among them was a song Sheriden had largely written called "Save Your Kisses for Me".
Question: What happened after the release of the song by David Cassidy?
Answer:
Finally their first two singles "Happy Ever After" and "Our World of Love" were released in 1973.