Americans are a diverse, wacky group of people, and here are some numbers to prove it. From the amount of trash we churn out to our very odd beliefs, here's a look at some startling facts about Americans.

1. Junk galore. Each American throws out about 4.4 pounds (2 kilograms) of trash every single day, according to the Environmental Protection Agency's latest 2012 figures. When the country's population is accounted for, that means some 1.4 billion pounds (635 million kg) of trash gets tossed in the U.S. daily. Although we're among the most wasteful people on the planet, we still generate less municipal solid waste than several island nations, particularly in the Caribbean. These small, isolated countries suffer from a lack of waste management options and infrastructure. Also playing a part in the waste problem are the large numbers of tourists, who produce loads of rubbish while traveling. A World Bank report from 2012 puts U.S. per capita municipal solid waste rate at about 5.7 pounds per day, but Trinidad and Tobago is the worst, at 14.4 pounds.

2. Energy gluttons. The Energy Information Administration reckons that of the total worldwide energy consumption in 2012 of 529 quadrillion British thermal units (Btu), the United States gobbled up 18 percent. Keep in mind the United States supports about 320 million people — just 4.4 percent of the world's population of about 7.2 billion.

Fewer Americans believe in God today than in 2005. (Image credit: SC Designs/Shutterstock.com)

3. Twilight of the gods. Although a strong majority of U.S. adults — 74 percent — believe in a god, this trend has dropped from 82 percent in 2005, a Harris Interactive poll found in 2013. Many other surveys have documented this rise in irreligiousness, putting the figure at around 20 to 30 percent of the population that is not theistic, a trend especially prominent among millennials.

4. Very superstitious. Notably, that same Harris poll found that 42 percent of Americans believe in ghosts, 26 percent in witches and 24 percent in reincarnation. The respective beliefs in Casper and multiple lives have remained steady since 2005, but witches dropped by 5 percentage points. [Are Ghosts Real? The Pseudoscience of Ghost Hunting]

5. Crackpot ideas. Meanwhile, 7 percent of Americans believe the moon landing was faked, according to a Public Policy Polling survey in 2013. Four percent supposedly copped to believing that "shape-shifting reptilian people control our world by taking on human form and gaining power" —although maybe these were just jokesters. Now that's a survey question.

6. Scientifically minded, part I. Perhaps a key reason for a large number of Americans' dubious notions: our mediocre education statistics compared with other countries. The most recent set of data from 2012 reported by the Program for International Student Assessment (PISA) bears this out. PISA — which keeps tabs on reading ability, science literacy and math among 15-year-olds — ranked the United States 27th in science out of 64 countries, and an even more middling rank of 35th in math.

7. Scientifically minded, part II. Despite less-than-stellar education rankings, the United States is the global leader in scientific publishing. The most recent data compiled by Thomson Reuters shows U.S. researchers authoring 27.8 percent of the approximately 1.27 million papers published in 2012, with China in second place at 14 percent. The United States has slipped in its global share of the pie, however, from a third of the approximately 850,000 scientific papers published in 2003, back when China accounted for merely 4 percent.

8. Bad medicine. According to a 2014 survey of 11 rich nations by the Commonwealth Fund, the United States ranked dead last in overall health care performance, in metrics such as equity of care, efficiency and "healthy lives." (A three-part measure of "mortality amenable to medical care, infant mortality and healthy life expectancy at age 60."). Another reason for this poor performance is actually a top ranking garnered by the United States — the highest health expenditure per capita. The average American spends $8,505 a year on medical care, more than every country, with the Swiss coming in second, at $5,643), but whose health care is ranked at No. 2 in the survey, behind the United Kingdom.

9. Early croakers. Speaking of life expectancy, the United Nations Department of Economic and Social Affairs and other organizations peg the U.S. around 40th worldwide, at 77.97 years overall, breaking down by gender as 75.35 for men and 80.51 for women. Life expectancy at birth indicates how long a newborn could expect to live if the patterns of mortality (at birth) were to stay the same throughout their lives. [Infographic: Global Life Expectancy]

10. Packing on the weight. A 2014 study in the journal The Lancet confirmed, again, that the U.S. is the most overweight country on Earth. Compared with 38 percent of men and 36.9 percent of women worldwide who are overweight or obese, 70.9 percent of men and 61.9 percent of women fall into that category in the United States. China has the second-highest absolute number of people with unhealthy weights, and a few countries, such as Egypt and Qatar, actually have higher obesity rates than America. Another study of U.S. men and women found that nearly 40 percent of men and nearly 30 percent of women were overweight (with body mass indexes between 25 and 29, and about 35 percent of men and nearly 37 percent of women were obese (BMIs of 30 or higher), according to the study published in June 2015 in the journal JAMA Internal Medicine.

11. The doc gap. In über-rich Qatar, folks sure have a lot of doctors to tend to them — 7.7 per 1,000 people, the highest globally, according to the most recent World Bank data collected in 2010. The U.S ranks low for developed nations, with only 2.5 doctors per 1,000 people (2005 data); most European countries, for instance, have more than three. Cuba, famously, has tons of doctors — 6.7 per 1,000 people (2010 data), tops in the world except for Qatar and also-crazy-rich Monaco, which has 7.2 per 1,000 people, according to data collected in 2012. The future looks bleak in this respect for U.S. residents, as one 2015 report by the Association of American Medical Colleges suggests by 2025 the country will be in need of between 46,000 and 90,000 more physicians to care for patients.

12. Connected, kinda. According to 2014 data from Nielsen, 71 percent of Americans own a smartphones. While on a par with many other developed nations, the U.S. lags way behind the United Arab Emirates, where 85 percent of UAE nationals own at least one smartphone. And Americans overwhelmingly choose Apple phones (42.7 percent of those surveyed), followed by Samsung (29.3 percent), the 2014 survey revealed.

13. Connected, kinda, part II. The World Bank reckons that 84.2 percent of Americans were Internet users in 2013. The top three nations? Norway at 95.1 percent, Bermuda at 95.3 percent, and Iceland at 96.5 percent.

14. Climate change outliers. Just 54 percent of Americans agree that ongoing climate change is largely the result of human activity, according to a 2014 survey by U.K. market research company Ipsos MORI. That slim majority contrasts with 93 percent in China, the highest of the countries polled, and is still well short of the 64 percent in Australia and the United Kingdom, the other countries agreeing least with the statement.

15. The sound from across the pond. Americans sync up with the British when it comes to music. Of the top 10 best-selling music artists of all time in the United States, according to the Recording Industry Association of America, four hail from the United Kingdom: The Beatles hold the top spot with 178 million albums sold, outpacing American country musician Garth Brooks, in the No. 2 slot with 135 million units sold. The rest of the top 10: Elvis Presley, Led Zeppelin (British), Eagles, Billy Joel, Michael Jackson, Pink Floyd (British), Elton John (British) and Barbara Streisand (all-American, alas).

16. Standing not quite as tall. For close to 200 years, spanning the Revolutionary War period in the mid-18th century to the World War II era in the mid-20th century, Americans were among the tallest people in the world, thanks to abundant land and resources in our relatively sparsely populated country, according to John Komlos, a professor emeritus of economic history at the University of Munich, as reported by BBC Future. Heights have leveled off, however, for around five decades, at around 5 foot 9 inches for men and 5 foot 4 inches for women. Western and Northern European populations, such as the Dutch, have since become the tallest on Earth, likely owing to better access to health care in these nations' socialized systems, Komlos said.

17. Motorized love affair. According to the most recent World Bank data, the United States had 809 motor vehicles per 1,000 people in 2011. That's tops in the world, except for the three tiny, rich European nations of Liechtenstein, Monaco and San Marino, with 826, 842 and a whopping 1,263 cars per 1,000 people, respectively.

18. Locked up. The United States incarcerates more people than any other country. According to the International Centre for Prison Studies, the country currently has more than 2.2 million people behind bars. That works out to about 22 percent of the total global population of inmates, shocking when considering that the U.S. supports just 4.4 percent of the world's population.

19. The bump. Among developed nations with complete, reliable statistics, the U.S. has the highest teen pregnancy rate, according to a recent report from the Guttmacher Institute. Statistically, out of 1,000 girls ages 15 to 19, 57 are pregnant at any given time. New Zealand is next at 51, followed by England and Wales at 47. Switzerland has the lowest teen pregnancy rate of eight per 1,000.

20. Truly a melting pot. America is less culturally diverse than you might think. Although on pace to be a "majority-minority" country by the early 2040s, wherein no one ethnic group dominates the population, as Caucasians long have, studies show America is not particularly diverse on a linguistic, ethnic or cultural level, compared with many other countries. In a 2013 German study, for instance, researchers used language and ethnicity as indicators of cultural diversity. The U.S. ranked in the middle, with countries such as Chad, South Africa and Papua New Guinea — with their myriad tribes, languages and distinct cultures and religions — ranking as the most diverse. Least diverse examples include Argentina and Rwanda, the latter because of the genocide of the Tutsi minority in the 1990s. A 2003 study in the Journal of Economic Growth showed similar results, ranking mostly African countries as the most culturally diverse.

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