Half the plants and animals in the world's most nature-rich areas are at risk of dying out if greenhouse gas emissions rise unchecked, wildlife experts have warned.
Even if goals to limit global warming to no more than 2C above pre-industrial levels are met, a quarter of species could still vanish from the most important natural areas on Earth, a scientific study found.
The study reveals the impact of climate change on plants, mammals, reptiles, birds and amphibians in irreplaceable and wildlife-rich places, from the Amazon to the Yangtze in China and the Galapagos.
Researchers looked at the impact of temperature rises and rainfall changes under different climate scenarios, from a failure to curb emissions to tough action to limit rises to 2C, on almost 80,000 species in 35 natural areas.
The Amazon, the Miombo Woodlands in southern Africa, home to African wild dogs, and south-west Australia are some of the most affected areas, research by the University of East Anglia, James Cook University and WWF found.
And species from giant pandas to snow leopards and polar bears could see their territory and food supplies reduced.
A failure to cut the carbon emissions that cause climate change, leading to a 4.5C rise above pre-industrial levels by 2100, could see 80% of mammals vanish in the Miombo Woodlands, and 67% of plants lost from the Amazon.
Increased temperatures and more erratic rainfall could become the "new normal", putting pressure on wildlife as varied as African elephants which drink large amounts of water a day, to tigers in coastal India and Bangladesh who could lose 96% of breeding grounds to rising seas.
If temperature rises are limited to 2C, which would require more action than governments have committed to so far, impacts would be less on wildlife, but still wide-ranging.
In the Mediterranean, 30% of most species would be at risk of dying out, while more than a third (36%) of plants could vanish.
Affected wildlife could include turtles, as warmer temperatures lead to more eggs hatching as females or failing to hatch altogether, while rising seas and storms can destroy nesting sites.
If species are able to move to new areas where the climate still suits them, it could reduce local extinctions from 25% to 20% with a 2C temperature rise, though plants and reptiles such as orchids and frogs cannot shift fast enough.
Lead researcher Professor Rachel Warren from the University of East Anglia said the study showed the benefits of limiting global warming to 2C for wildlife.
"We studied 80,000 species of plants, mammals, birds, reptiles and amphibians and found that 50% of species could be lost from these areas without climate policy," she said.
"However if global warming is limited to 2C above pre-industrial levels this could be reduced to 25%."
The report did not look at the impact of limiting temperature rises to just 1.5C, which countries pledge to aim for under the global Paris Agreement on climate change, but it would be expected to protect more wildlife, she added.
Dr Stephen Cornelius from WWF-UK said of the report: "This is a global problem, it shows that across 35 priority places scattered all over the world, all of them over the last 50 years, across all the seasons, have seen temperatures rise.
"We can already observe changes and impacts, and projections show they will continue.
"There's no area that will be unaffected, though there are some that are more vulnerable, and there are some areas that are more resilient than others."
He warned "plant species are incredibly vulnerable", with potential knock-on impacts for other species such as birds that might rely for food on a specific plant.
The study is published in the journal Climatic Change, ahead of Earth Hour, a global environmental event organised by WWF which takes place on March 24.