Why don’t wild lions attack human tourists in open vehicles?
Douglas Hall, Suwanee, Georgia
It’s all about predator-prey dynamics: A lion wouldn’t think twice about going after an individual human, but a motor vehicle is just so much larger than any animal a lion would usually attack as prey (or perceive as a threat it could handle). This dynamic also helps explain why animals do things or have characteristics to make themselves look larger—to avoid being perceived as easy prey.
Craig Saffoe, Curator of great cats, National Zoo
What would happen to the Earth if the Moon were destroyed?
Rose Mary, Bundscho, Houston
There’s a vibrant literature on the subject on the Internet, but the logic chains are rather long and sometimes hard to follow. In reality, any event violent enough to destroy the Moon would likely destroy the Earth, too. Speaking less literally, the Earth without the Moon would be a planet without tides—and with a less compelling night sky.
Curator of astronomy and space sciences, Air and Space Museum
How long ago did humans develop the ability to speak and form words?
Marsha Cox, Kure Beach, North Carolina
We don’t know about spoken words; they don’t turn into fossils that we can discover and date. But written words date back about 8,000 years, and evidence of artistic expression, such as sculptures and paintings, is much more ancient. For instance, humans began using pigments like ocher and manganese to mark objects, and possibly their own skin, between 320,000 and 260,000 years ago.
Briana Pobiner, Paleoanthropologist, Natural History Museum
We often hear that climate change is raising the sea level. Is it rising globally or in specific locations?
Wayne Gilbert, Westminster, Colorado
The sea level is rising worldwide, but not uniformly, due to differences in ocean circulation, winds, the shape of local bodies of water, seafloor characteristics and even the gravitational pull of polar ice sheets. The elevation of land may also change over time in an equally variable fashion. Combined, the two factors create a great deal of local variation in the rise of sea elevation compared with land elevation, which we call relative sea level rise.
Patrick Megonigal, Climate change ecologist, Smithsonian Environmental Research Center
Who invented yoga?
Debbie Peck, Germantown, Wisconsin
No specific individual or spiritual tradition. Yoga emerged in northern India about 2,500 years ago, as men and women of various faiths began to renounce social bonds and turn to meditation as a means of rising above the pain of existence. By the seventh century A.D., the core concepts, practices and vocabulary of almost every yoga system were established, though variations and expansions continue.
Debra Diamond, Curator, “Yoga: The Art of Transformation,” Sackler Gallery
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