A team of international scientists has rejected the idea that the planet could face a sudden and irreversible ecological shift as a result of largely human-driven pressures, suggesting that such global transformations are more likely to occur over a long period of time. While earlier studies have warned that ecological pressures — including climate change, biodiversity loss, and over-exploitation of resources — could drive the planet toward a dangerous “tipping point,” the new paper says the ecosystems of different continents are not sufficiently interconnected for such a global shift to occur . And while as much as 80 percent of the biosphere includes ecosystems that have been affected by human activities, major ecological shifts driven by these human pressures “depend on local circumstances and will therefore differ between localities,” said Erle Ellis, a scientist at the University of Maryland, Baltimore County and co-author of the paper, published in the journal Trends in Ecology and Evolution