Many corporations claim their products are "green-friendly." But how do you know if what they're selling is truly eco-safe? SciLine interviewed Thomas Lyon, professor of sustainable science, technology and commerce at the University of Michigan, on how to buy environmentally sustainable products, whether carbon credits actually work and the prevalence of greenwashing.

Below are some highlights from the discussion. Answers have been edited for brevity and clarity.

One of Kenya's oldest wild lions was killed by herders and the government has expressed concern as six more lions were speared at another village on Saturday, bringing to 10 the number killed last week alone.

The male lion named Loonkiito was 19 years old and was described as frail by Kenya Wildlife Service spokesperson Paul Jinaro, who said it wandered out of the Amboseli national park into a village in search of food on Thursday night.

Deep in a cool, damp cave in Vermont, tens of thousands of furry, chocolate brown creatures stir.

The little brown bats, survivors of a deadly fungus that decimated their population, went into hibernation last fall. Now in early May, they're waking, detaching from their rock wall roosts and making their first tentative flights in search of the moths, beetles and flying aquatic insects they devour.

Stragglers packed up belongings in cars, trucks and a least one pickup truck before a looming deadline on Friday to evacuate a village in eastern Switzerland that is facing an urgent rockslide threat.

About 2 million cubic meters of rock on an Alpine mountainside overhead could soon come crashing down.

The Spanish government announced 2.2 billion euros ($2.4 billion) worth of drought response measures, including funding for urban water reuse and further aid for struggling farmers.

Currently, 27% of Spanish territory is in a drought "emergency" or "alert." Spain recorded its hottest and driest April ever last month.

Attorneys for young people suing Montana over damages caused by climate change said officials repealed the state's energy policy in a last-minute bid to avoid a trial sought by the plaintiffs to highlight the dangers of fossil fuels.

The two sides are due in court Friday for arguments before state District Judge Kathy Seeley. A two-week trial is scheduled to begin June 12.

Spain says it plans to ban outdoor work during periods of extreme heat.

Second Deputy Prime Minister Yolanda Díaz told reporters that the government will modify legislation covering occupational risks to prohibit outdoor work when the state weather agency, AEMET, issues red or orange alerts.

New Mexico and its Democratic governor are being sued over alleged failures to meet constitutional provisions for protecting against oil and gas pollution, a challenge that comes as the nation's No. 2 oil-producing state rides a wave of record revenue from drilling in one of the most prolific collection of oil fields in the world.

A coalition of environmental groups filed a lawsuit Wednesday in state district court, marking the first time the state constitution's pollution-control clause has been the basis of such a legal claim. The 1971 amendment mandates that New Mexico prevent the despoilment of air, water and other natural resources.

The Biden administration is proposing new limits on greenhouse gas emissions from coal- and gas-fired power plants, its most ambitious effort yet to roll back planet-warming pollution from the nation's second-largest contributor to climate change.

A rule to be unveiled Thursday by the Environmental Protection Agency could force power plants to capture smokestack emissions using a technology that has long been promised but is not in widespread use in the U.S.

When Joe Seaman, the city planner for the working class town of Cohoes, New York, Googled the term "floating solar," he didn't even know it was a thing. What he did know is that his tiny town needed an affordable way to get electricity and had no extra land. But looking at a map, one feature stood out, he said. "We have this 14-acre water reservoir."

Seaman soon found the reservoir could hold enough solar panels to power all the municipal buildings and streetlights, saving the city more than $500,000 each year. He had stumbled upon a form of clean energy that is steeply ramping up. Floating solar panel systems are beginning to boom in the United States after rapid growth in Asia. They're attractive not just for their clean power and lack of a land footprint, but because they also conserve water by preventing evaporation.