Hong Kong bowed Friday to years of pressure from environmental groups, saying it would no longer allow shark fin to be served at official functions. Connect With Us on Twitter Follow @nytimesworld for international breaking news and headlines. Twitter List: Reporters and Editors The authorities are “determined to take the lead and set a good example on this front,” a government statement said. The initiative goes “beyond the minimum expectation laid down” in the United Nations treaty that governs trade in threatened species, the statement said, and it also applies to bluefin tuna and black moss, a type of algae popular in Asian cuisine. Scientists estimate that as many as 100 million sharks…