My friend and I are arguing over the year humans first appeared. I say humans first appeared in the year 28028 (BC). My friend says it was 237629 (BC). Who’s right? I don’t mean to be selfish, but I just feel pretty sure that I’m the one who’s right.
Neither of you. 
Your numbers are both way too precise. Might as well include the precise date and time…it wouldn’t reduce your chances of being correct within the precision you’ve defined all that much.
Your friend is closer - the first anatomically modern humans appeared about 200k years before the present. Your number is closer to when our species found their way to East Asia and the Americas, which, any way you slice it, is not a reasonable way to define ‘the first human’.
If we define ‘human’ as the genus homo, even your friend is way off (still closer, though, obviously).
You’re serious, right?
You and your friend are both wrong. The earliest species of human, Homo habilis, first appeared around 2.3 million years ago, about nine times earlier than your friend says. Even modern man, or Homo sapiens sapiens, first appeared around 200,000 years ago, which fits in more closely with your friend’s guess.
Ninja’d by Kamino Neko.
Reminds me of a joke about a tour guide at a natural history museum. He pointed to some dinosaur bones and said, “These bones are 140 million and four and a half years old.”
When asked how he could be so precise, he responded, “Well, I started my job as a guide here four and a half years ago, and they told me the bones were 140 million years old. So now their age must be 140 million and four and a half years.”
Did you get those exact-looking numbers by converting from metric? Like those news reports that say the epicenter of the earthquake was “620 miles” north of BFE, having converted from somebody on the ground who said “about 1,000 kilometers”. There’s a term for that, I think it is “spurious exactitude”.
Well, let’s work it out and see. What are the conversion factors between metric years and English years?
Well a metric year is 10 metric months of 10 metric days which are 10 metric hours long (100 metric minutes) long… carry the 1… subtract 1 for each leap year… I come up with 1 metric year equals a little less time than it takes to wear out a cheap pair of sneakers; in English years, about 8 months 4 days 9 hours 37 minutes and 12 seconds (approx.).
It changed when Urglot Bearkiller’s son Jonathan changed his name…
Wow! I love it.
That does happen (maybe not for years, but some units). I always wondered by normal human body temperature was given to be 98.6 degrees F. It seemed mighty precise for something that varies from time to time and person to person. Until I realized one day that 98.6 F was equal to 37 C.
I thought the normal human body temperature was supposed to be 100 degree, but Fahrenheit fudged the math.
I just figured he had a slight fever when he took his own temperature.
Then you double it and add 30.
When I was little I got a book on dinosaurs, which told me they died out 65m years ago. A year later, I was claiming they died out 65,000,001 years ago.
Obviously, then I realized my mistake - I checked the publication date and realized it was more like 65,000,005 years.
I see that a lot for currency exchange rates in newspaper reports. Something worth “£15,000,000” is then listed as “AU$27,334,890.00”
Is that like the coin dated 50 B. C.? 
I actually came in to tell this joke!
“Spurious exactitude”. I’m going to have to remember that.
Seems like it would be a good band name!