Rapid population growth and poor infrastructure have put two out of three cities in Africa at "extreme risk" of the threats posed by climate change, according to a new analysis released Wednesday.

Johannesburg Zoo is under mounting pressure to send a lonely elephant to an animal sanctuary after her male companion died last month.

Protesters dressed in elephant costumes have been demonstrated at the zoo entrance, while online petitions have garnered over 100,000 signatories, clamoring for 39-year-old Lammie to start a new life in the company of other elephants.

A rapidly spreading, late-season wildfire in northern California has burned 20,000 acres of land and prompted authorities to issue evacuation orders for thousands of people.

Air pollution in New Delhi hit hazardous levels Thursday after a night of free-for-all Diwali fireworks, despite Supreme Court efforts to curb the smog-fuelling partying.

When an endangered female North Atlantic right whale spends months, even years, disentangling itself from cast-off fishing nets, there's not much energy left over for mating and nursing calves.

Coping with such debris, along with ship collisions and other forms of human encroachment, have severely stymied recovery of the majestic sea mammals long after explosive harpoons and factory ships nearly wiped them out, according to a study published Wednesday.

Extracting a dollar's worth of cryptocurrency such as bitcoin from the deep Web consumes three times more energy than digging up a dollar's worth of gold, researchers said Monday.

There are now hundreds of virtual currencies and an unknown number of server farms around the world running around the clock to unearth them, more than half of them in China, according to a recent report from the University of Cambridge.

Wind farms act as a top "predator" in some ecosystems, harming birds at the top of the food chain and triggering a knock-on effect overlooked by green energy advocates, scientists said Monday.

International efforts to save some of the world's rarest and economically important plants from climate change are doomed to fail because their seeds cannot be stored, researchers warned Friday.

As the planet heats and mankind continues to decimate natural habitats, scientists concede that the only way to save some types of vegetation is in seed banks -- giant repositories of thousands of species preserved for future generations.

As the sun rises over the mountains behind the Dead Sea, Anton Khalilieh squints into a telescope and scans the skies.

If Brazil's far-right President-elect Jair Bolsonaro wants to make good on his promise to reboot the economy, he should stop his attacks on the environment, according to the World Wildlife Fund.