Nicholas Mangan grew up in Australia in the early 1990s, when the weather was beginning to change. In recent years, extreme systems have hit the continent’s Pacific shores with more intensity and violence. Drought and severe fire seasons have become mainstays during the summer; meanwhile the country’s renowned coral reefs are bleaching and dying. For 20 years Mangan has been exploring the complex relationship between human activity and the environment. The exhibition “A World Undone” presents eight of his recent sculptural works, including Core-Coralations. Its squared-off structures of polystyrene, a hard-to-degrade material, suggest tombs for dead coral. —Elena Clavarino