I'd never seen the yakka trees on previous trips to Kangaroo Island. But now, clusters of them have shimmied up toward the sky like upside-down palms. Their spearlike trunks, designed by nature to germinate with fire, sprouted recently, a result of the catastrophic 2020 “black summer” bushfires, which engulfed Australia. Fast-moving flames reduced half the island to embers, claiming the lives of thousands of its animals, including more than 60,000 koalas. But the hardy native trees are a symbol of the regenerative power of the bush.