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THE EARLIEST evidence leans toward beer, says Theresa McCulla, a curator at the National Museum of American History. Archaeologists found traces of cereal grains on mortars near Haifa, Israel, dated at around 13,000 years old. The previous record belonged to a drink discovered in China dating back 9,000 years; it resembled a mix between beer and grape-based wine. Beer and wine were both relatively straightforward to make, since the sugars in mashed grains or grapes naturally start to ferment when exposed to wild yeasts at the proper temperature. Distilled spirits such as vodka and whiskey involved a more complicated understanding of chemistry and likely did not appear until the Middle Ages.

Q: At the shore, I see two high tides each day, but the Moon is overhead only once a day. What causes the second high tide?

— Bill Kay | Clifton, Virginia

HIGH TIDES make the ocean swell twice a day: once when the Moon is overhead and then again when it’s directly on the far side of Earth, explains Alex Parker, a former postdoctoral fellow at the HarvardSmithsonian Center for Astrophysics. The second high tide is a response to the Moon’s gravity tugging at Earth’s orbit. It creates a centrifugal force that can be felt most strongly on the other side of the world. (Think about the way a person in the back seat of a car gets pushed against the window as the front of the car suddenly turns.) This makes the ocean water spread out and elongate on the far side of the planet, about 12 hours after the earlier (and stronger) high tide. Smaller bodies of water, and even the ground beneath us, are subject to the same gravitational pulls, but the effects are too tiny for us to notice.

Q: How did the dinosaurs become as big as they did when the mammals that followed their extinction were so much smaller?

— Brian Vespucci | Frisco, Texas

DINOSAURS HAD A LOT of time to evolve, explains Matthew Carrano, curator of Dinosauria at the Natural History Museum. The earliest dinosaurs, which emerged about 230 million years ago, weighed no more than a few pounds. The largest—longnecked multi-ton sauropods like the Brachiosaurus— appeared tens of millions of years later. Dinosaurs also had an advantage over mammals: They laid eggs. That reproductive period—quicker than a live birth, and with a lot of offspring—made it easier for large dinosaurs to replace their numbers. By comparison, large mammal populations can be very vulnerable. An elephant’s 22-month gestation period produces only one baby. But it wasn’t all success for giant dinosaurs: being so large likely contributed to their vulnerability when a giant asteroid struck the Earth, while mammals and other smaller species weathered the crisis.

Q: Why did the Big Bang result in an orderly universe? Don’t explosions cause disorder?

— Steve Baum | Tucson, Arizona

YES, EXPLOSIONS are disordered, and the Big Bang was like an explosion. But the laws of physics do allow for ordered systems to evolve from disordered ones, says Howard A. Smith, senior astrophysicist at the Harvard-Smithsonian Center for Astrophysics. Gravity in particular is the cosmic force that brings matter together into more compact, more ordered structures.

Q: Which came first: beer or wine?