Garbage doesn't lie
In addition to scientific equipment, the Voyager spacecraft each carry, out beyond the solar system, a golden record encoding information about the earth and our human civilization. These time capsules contain examples of the best aspects of humanity - language, music, art, and scientific achievements. Environmental destruction, war and cable tv didn't make the list. Neither did garbage. And yet, every single time you throw something away, you're contributing to a collective time capsule. Because buried deep within the landfills that dot the Earth lies precious information about who we are, how we live and what we really care about. Archaeologists use heaps of trash to study people and culture, and even have a special, nice-sounding name for garbage piles: middens. In one midden near Rome, archeologists uncovered 25 million containers for carrying olive oil, telling us that Romans used a LOT of olive oil but almost none of it came from Rome - most was from Spain and Egypt. And we know from shell middens that the Maori people of New Zealand hunted moa and seals early on, but later had to switch to fish, shellfish, and small birds as the moa and seals became overhunted. Digging through more recent history, a midden outside of George Washington's home revealed the belt buckles he wore, the china he used, and the meat he and his guests ate off of that china. Even now, in our era of modern record keeping and data, we may need to look through the garbage to see what we're really like. In the 1980's, there was huge outcry about the gross quantity of garbage humans were making, with many environmental groups painting a picture of disposable diapers and fast food packaging filling up our landfills. It's true that we were producing a lot of trash, but when researchers examined what was in those landfills, diapers and fast food containers accounted for less than 2 percent of new landfill volume. The majority was construction waste and paper. Around the same time, a professor in Tucson interviewed people about their eating habits, then went through their trash to see what they threw away. It turns out that people and their garbage tell two very different stories. People overreported healthy foods, and underreported foods they considered bad. For example, participants reported drinking only half as much alcohol as the bottles in their trash indicated. And everybody underreported how much fat they ate -- except people who had lived through WWII. Those generations tended to overreport butter, which was heavily rationed during the war and consequently considered valuable and healthful. So a survey or carefully crafted time capsule is probably biased towards the best parts of our lives - the parts we want people to remember and extraterrestrials to know about. But our trash doesn't lie.
