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Human Numbers 

• 0.000000000017 - degrees Fahrenheit (170 billionths of a degree above absolute zero) of lowest temperature ever recorded (by cooling rubidium atoms, source)
• 0.1% - 0.2% - Live births with gender ambiguous enough to become the subject of specialist medical attention, such as surgery to disguise their sexual ambiguity (WP)
• 0.3 - Avg IQ points gained each year since 1947 (WISC, WAIS, Stanford-Binet) (WII p112)
• 1 - IQ points per generation lost due to U.S. reproductive patterns (WII p101)
• 1% - Human live births with some degree of sexual ambiguity (WP)
• 3% - Children in western nations fathered by someone other than their presumed father (BWT p179) 
• 4 - Usually the number of intermediary friends needed to reach a random stranger (“When considering another person in the world, a friend of your friend knows a friend of their friend, on average.”) (TR)
• 6.32 - Average inches of gay men's penises; 5.99 average inches of straight men's penises (BWT p128) 
• 10 - There are 10 times more bacterial cells than human cells in the human body (WP)
• 15-30% - Rate at which people are wrong about things they consider 98% certain (Black Swan)
• 16% - Percent of the variance in IQ accounted for by variation in brain volume (Scientific American Mind, Aug/Sep 2008 p63)
• 17.5 - Avg times people laugh per day (Rod Martin, University of Western Ontario, \"The Psychology of Humor\" 
• 19 - Median number of young men’s thought about sex per day (10 times in young women; men also thought about food almost 18 times per day and sleep almost 11 times per day, compared to women’s median number of thoughts about eating and sleep, at nearly 15 times and about 8 1/2 times, respectively. ( Ohio State )
• <=20 seconds - Short term memories
• 20Hz to 20kHz - human hearing range (xiph.org)
• 30-60 minutes - Time until peak caffeine effect; declines from there to half strength in about 3-4 hours
• 51% - Chance that a typical coin flip will result in the side that was facing up before the flip (see coin flips are not 50-50 )
• 56% - Portion of psychology subjects 2003-2007 that were WEIRD (Western, Educated, Industrialized, Rich, Democratic) (BWT p xvi) 
• 70% - Approximate portion of U.S. food that is genetically modified
• 80% - Percent of women in the history of the human race that have reproduced; 40% of men (BWT p80) 
• 93% - Proportion of human bodies that is stardust
• 98% - Proportion of sexually active Catholic women in America who have used forms of contraception banned by the church (Reuters)
• 100 - There is 100 times as much bacterial DNA in humans as human DNA (Bonnie Bassler, Ted Talks)
• 142 mph - Winds in Long Beach, WA in 1970
• 5,000 years ago - Estimated time of Most Recent Common Human Ancestor (Human MRCA)
• 11,000 years ago - Clovis peoples reach North America from Siberia via Bering Strait landbridge (previously considered first humans in America)
• 19,000 years ago - Date of artifacts found at Meadowcroft, oldest provable human habitation in North America (The First Americans: In Pursuit of Archeology's Greatest Mystery - James Adovasio)
• 20,000 years ago - Our ancestors reach Europe
• 25,000 years ago - Homo Sapiens had become only living species in hominin genus with exception of Homo floresiensis ("Hobbits")
• 45,000 years ago - Humans migrate from Africa to Middle East and Central Asia, the "nursery" or second staging area of mankind
• 50,000 years ago - Humans first migrate from Africa - to coasts of Arabia, India, and SE Asia
• 60,000 years ago - Single common father ancestors of all present human beings (Y chromosome Adam)
• 100,000 years ago - Date some archeologists believed humans migrated out of Africa, must be reconciled with genetic markers (50,000)
• 45,000 - Persons in the U.S. who die annually due to lack of health insurance (Americann Journal of Public Health)
• $60,000 - Amount above which additional money does not add any experiential happiness for Americans (Kahneman)
• 100,000 miles - Total length of blood vessels in the human body ( http://www.madsci.org/posts/archives/jan99/916069852.An.r.html ) 
• 100,000 years ago - First traces of unambiguous use of symbols (NYRB 10/22/09)
• 140,000 years ago - Mitochondrial Eve, common mother of all mankind
• 200,000 years ago - Homo Sapiens appear
• 500,000 years ago - human brain size had reached current capacities (NYRB 10/22/09)
• 5-7 million years ago - Common ancestor of humans and chimpanzees (from DNA, not fossils, NYRB 10/22/09)
• 10 million - Odds that your vote will affect the presidential election = 1/10,000,000 (FiveThirtyEight.com)
• 300 million years ago -  Pittsburgh on the tropical east coast of Laurasia, crashing with Gondwana supercontinent plate to form mountains that erosion would wear down to the Alleghenies and Appalachians
• 383.2 million years ago to 298.9 million years ago - The Pennsylvanian Period, AKA Upper Carboniferous or Late Carboniferous) period
• 7 billion - people alive today
• 107 billion - people who have ever lived (Population Reference Bureau)

• 7.2 trillion degrees F - Hottest known temperature in the universe, recently created in the lab (source)

• 10-50 trillion - Number of cells in the human body ( http://ask.yahoo.com/20020625.html )
• 86 Billion - (Not 100 billion) - Number of neurons in human brain (Skeptics Guide #471) 
• 2.5 Petabytes - Estimated storage space of human brain (connections, not 1 bit/neuron) (SciAm)
• 10^31 (Ten million trillion trillion) - Estimated number of phages on earth (more than all other organisms on earth together)
• 10^600 - Odds of a mother conceiving a child genetically identical to another (but not an identical twin) (Source)
• 8.06^67 (=52!) - Possible combinations of a deck of cards - If you shuffle a deck of cards there is a very good chance that a deck has never been ordered like that before.

Nature Numbers

• 186,283 miles/second - Speed of light (c) = 3x10^10 cm/second
• 1 million - Bacteria in approx. mililiter of fresh water
• 5 million years - Common ancestor to chimpanzees and humans (CUK p.86)
• 0.9 to 1.5 billion - Years until luminosity of the sun eliminates intelligent life on earth (Bostrom et. al.)
• 3.5 billion - Years until luminosity of the sun sterilizes entire earth biosphere (Bostrom et. al.)
• 10 billion - Upper limit of estimates of total number of species ever to have lived on the earth ( http://astrobiology.nasa.gov/ask-an-astrobiologist/question/?id=143 )
• 10^80 - Atoms in the known universe (Source)
• 5 nonillion (5x10^30) - Approx. bacteria in the world
• 3.5 billion - Years, Oldest known fossils
• 4.28 billion - Years old, oldest rock known (Canada) ("Science" SGU #167)
• 13.7 billion - Years, age of the universe (SGU, #223, 10/28/2009)
• ~47 billiion - Light years of the radius of the observable universe (we can see the light, but it was much closer when it left)
• universe size revised in 2003; rate of expansion is growing over time, we don't know if it is a constant acceleration (SGU #223, 10/28/2009);
• see only 4% of stuff in the observable universe (i.e. not so far away that light will never reach us)
• best guess is that observable universe is a few percentage points of the entire universe
• We don't know if the universe is finite in size, we only know that it is finite in age
• 65 billion - Neutrinos passing through each centimeter of matter on earth each second
• 100 billion - Estimated minimum planets in the Milky Way (Seattle PI, 2012)
• 426 billion - Trees on earth (approx 61 trees/person) - [Krulwich 11/12/08]
• 10^18 cm = 1 light year
• 0.2 ounces - Weight a 150lb person loses driving from SeaTac to UW ("an abrupt change in gravity measurements along a line that slices from Hood Canal through south Seattle. North of the line are lighter, sedimentary rocks. To the south, the rocks are dense and heavy....The gravity gradient is one of the sharpest ever detected in the United States." --  "Full Rip" -- Sandi Doughton)
• 10^-8 cm - Angstrom (=~ diameter of atom)
• 1836x - Mass of proton to mass of electron
• 6.022 x 10^23 atoms/mole - Avogadro's number
• 40 miles/year - Magnetic north pole currently migrating northward (10 miles/year in early 20th century) (earthsky.org)
• 600 miles - Distance magnetic north pole has moved northward since first located precisely in early 19th century
• 150 mph - Winds on Long Beach peninsula (http://www.pacificcohistory.org/hurricane.htm) Dec 2-3, 2007 
• Gavitational/weight changes on humans (SI 18.5 p513)
• 0.000035% - change in weight from moon overhead to on the horizon
• 0.3% =~ change in weight due to changes in weather
• 0.5% =~ change from moving from place to place on earth's surface
• 1% =~ weight change from meal

Traffic Numbers

• .5 mile = as far as most people will walk for things like groceries - p138
• 30 seconds - Tipping point for jaywalking and accepting smaller gaps to turn against traffic - p225
• 3 seconds - In 80% of crashes and 65% near crashes, driver was not paying attention to traffice for 3+ seconds before event (trouble starts at 2 seconds)
• 0% - Effect that anti-lock brakes have on reducing crashes (never explained) - p263
• 5% - Crashes that involve two vehicles moving in the same direction - p253
• 50% - auto accidents are at intersections - p178
• 85% - People killed in work zones that are drivers or passengers, not workers - p45
• 90% - Fewer fatalities at roundabouts than intersections with stop signs (76% fewer injuries, 40% fewer crashes) - p179
• >50% - Traffic fatalities that are single vehicle, run off road - p185
• 2x - Chances that striking pedestrians at 36-45 mph will kill them compared to 31-35 mph - p206
• 4x - Chances that striking pedestrians at 36-45 mph will kill them compared to 26-30 mph - p206
• 2.5x - Death rate on rural, non-interstate roads compared to all other roads - p257
• 7x - Chances that person drinking within legal limits will be in a fatal crash - p251
• 10x - Chances that people with personality disorder will get in a serious crash - p261
• 15x - Chances that people in cars going 50mph will die relative to cars going 25mph - p252
• 13x - Chances that legally drunk person will be in fatal crash - p251
• 22x - Chances of motorcycle ride resulting in death relative to average car
• 1.3/100 million miles - Traffic fatalities of male drivers
• .73/100 million miles - Traffic fatalities of female drivers
• 1/100 - Chances that average drive (15,500 miles/year) will die in 30 years of driving - p249
• 10,000 - Estimated lives could have been saved if U.S. did what U.K. did in the 90s. - p271

Birds killed annually by (Bird Conservancy):

    400,000 - Windmills

  4,000,000 - Coal and Gas (land degradation, air pollution, buildings)

 10,000,000 - 50,000,000 - communication towers

 80,000,000 - Cats

200,000,000 - 1,000,000,000 - Buildings

Technology Numbers

• Lines of Code - visualized, major apps 
• 30% of web sites are Wordpress (source)
• 239,000 - servers Akamai was running in 2018 
• 10.3 million concurrent viewers - 2018 Indian Premier League (world record for live streaming)
• 28 billion - credential stuffing attempts detected by Akamai May-Dec 2018 -  Global State of the Internet Report