Test your knowledge of all things autumnal.

Bacteria live everywhere in your body, including your gut. These microbes have quite an impact on your health. Do you know what they do?

Whether it's a white lie or a whopper, fibs are part of our daily lives. We like to think we're honest but, well, we're not. Test your falsehood expertise.

The Earth's mountains, rivers, animals and rocks have been around for millions or billions of years. Do you know which ones have been around the longest?

National Park and Earth Week are right around the corner — see how much you know about our nation's protected areas.

From the cheetah to the hare, so many creatures are wickedly quick. Test your trivia smarts on what makes them so swift.

Whether you're crying tears of joy or crying over spilled milk, how much do you really know about the tears rolling down your face?

Lightning is more than just a stunning spectacle. Take our quiz to see how much you really know about this electrifying natural wonder.

Think you know everything about that special day of scary movies and sugar highs? Test your Halloween smarts ... if you dare.

You use pasta in sauce, in soups and in salads. But do you know the names of the different pasta types?

When the going gets tough, some animals get going — to bed. Take our hibernation quiz to see how much you know.

Every two years, the National Science Foundation asks 10 questions to see how much Americans know about science.

Former Carter advisor and energy guru S. David Freeman will become the 'environmental mayor' of L.A.

OPT harnesses ocean power with some bright yellow buoys (VIDEO).

When it comes to decisions on electricity and energy policy, women do not have the facts they need.

Web site and mobile app help you find the lowest gas prices in your area.

The 57,000-acre San Andres Refuge, which works to restore desert bighorn sheep, launched its quest for energy independence in 2005 and has implemented several s

Harish Hande launched his solar company to dispel the myth that renewable energy was too expensive for poor people. The West could learn something from him.

Music for Relief, a charitable network of music greats, wants to help light up the darkest homes in Africa though the Power the World campaign. The goal: Lift m

Japan's plan to wean off nuclear power could help lead a global push toward cleaner, more efficient civilization, says U.S. energy guru Amory Lovins.

A well-known Chinese solar power company has filed for bankruptcy, but this may actually be a sign of health for the industry.

El Hierro, the smallest of the Canary Islands, is becoming energy self-sufficient by relying solely on wind turbines and hydroelectricity.

MNN introduces you to the key characters in the Eco-bama drama including Steven Chu, Carol Browner and more.

Whether it's fresh or canned, pumpkin freezes really well.

Thousands of pounds of moldy cardigans and unsellable denim shorts are being burned in lieu of oil and coal at Västerås near Stockholm.

Illegal dung dumping is on the rise as the already-strong Dutch dairy sector continues to grow.

While easy to focus on the gross-out factor, the tale of a stranded train filled with sewage sludge shines a light on the complicated afterlife of our waste.

You may love Amazon Prime, but the environment doesn't.

Copenhagen gains an unusual new landmark in the form of a multitasking waste-to-energy plant designed by Bjarke Ingels Group that functions as a ski slope.

As much as 66 metric tons of human excrement from visitors to Alaska's Denali National Park could soon be released into the pristine Alaskan coast.

Getting along with neighbors can yield big health benefits for birds, a new study finds. It's probably good for us, too.

The newly identified species weaves silky air chambers to survive high tide.

Thanks to the 24-hour news cycle and social media, it's impossible to tune out these politically turbulent times. Here's how to tune in and stay sane.

The release, quickly dubbed "Climategate 2.0" after the initial 2009 "Climategate" hacking, drew strong condemnation from scientists involved in the emails, as

Timing matters: Flowers bloom, insects emerge, birds migrate, and planting and hunting seasons are carefully coordinated times in order to take advantage of wha

New flexible glowing sheets are inexpensive, easy to recycle, and could someday replace lightbulbs and OLED technology.

Authentic sounds of the wild can now be downloaded for free to your iPhone. Assign your friends their own unique howl, hoot or roar.

Who needs nature when you can have virtual reality windows that simulate any setting with the flick of an iPhone app?

Empowering consumers to make smart decisions can change the marketplace and shrink our national energy footprint.

The new towers collect much more sunlight during the mornings, evenings and all days of the year regardless of clouds or shadows

A new style of tiny lithium battery that can charge wirelessly could help make cyborg grafts an imminent reality.

Innovative technology enables electronic devices to function in contact with body tissues.

Today's technology allows us to look deep into what was previously invisible, revolutionizing our understanding of microorganisms.

Sustainability played a key role at this year's CES with both the CEA and Bosch donating materials and funds to Habitat for Humanity green building efforts.

Invention start-up Quirky and GE launch the Aros Smart Air Conditioner, a window unit with added brains and good looks.

Almost everything we use runs on direct current, so why are our houses still wired for alternating current?

Intel's Compute Stick turns your big TV into a working Windows computer.

Even though native bees don't produce honey, they're incredibly important, says author Paige Embry. She explains how to help them in "Our Native Bees."

Famed naturalist and conservationist John Muir was so much more than the father of our national parks.

Pando, the world's largest-known organism, is dying. But there might still be time to save this wonder of nature.