Nearctic realm represented by the Madrean Region. Although North America and South America are presently joined by the Isthmus of Panama, these continents were separated for about 180 million years, and evolved very different plant and animal lineages. When the ancient supercontinent of Pangaea split into two about 180 million years ago, North America remained joined to Eurasia as part of the supercontinent of Laurasia, while South America was part of the supercontinent of Gondwana. North America later split from Eurasia. North America has been joined by land bridges to both Asia and South America since then, which allowed an exchange of
Gondwana Choirs Australian composers. Gondwana Choirs Gondwana Choirs is an Australian national children's choir organisation. It was founded in 1989 as Sydney Children’s Choir by Lyn Williams OAM, who is its artistic director, and is located in Millers Point, New South Wales. Gondwana Choirs has three divisions, Sydney Children's Choir, Gondwana National Choirs and Gondwana Indigenous Children's Choir, and includes several different choirs: Gondwana Choirs auditions nationally and meets in January for a two-week camp of intensive rehearsal. Choirs then typically undertake one or more tours during the year. Gondwana Choirs also runs a Composer School and a Conducting Internship, and commissions