2187: Geologic Time

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Geologic Time
Ok, well, we'll be sure to pay you sometime soon, geologically speaking.
Title text: Ok, well, we'll be sure to pay you sometime soon, geologically speaking.


Analogies to explain the passage of billions of years are often used in popular science explanations, to help compress these huge spans of time into something the human mind can comprehend; the football field analogy is one such analogy. The Earth is approximately 4.54 billion years old; if you were to present a timeline of Earth as long as a gridiron football field (100 yards or 91 meters), then each inch of that length would comprise more than 1.26 million years of Earth's history and each millimeter nearly 50,000 years.

  • Complex life refers to the various animal species which arose in the Cambrian explosion 541 million years ago; the length of time that complex life has existed would translate to 11.9 yards on the football field.
  • Dinosaurs are estimated to have first evolved as early as 244 million years ago, and survived until the Cretaceous–Paleogene extinction event 66 million years ago; thus it would begin at the 5.37-yard mark and continue up to the 1.45-yard mark.
  • Although the evolution of mammals can be dated to around 220 million years ago (depending on definition), they didn't truly become dominant until the aforementioned extinction event paved the way for them to grow and diversify 66 million years ago. The age of mammals therefore extends from the 1.45-yard mark to the goal line (present day).
  • Homo sapiens is estimated to be 350,000 years old; our species takes up only a meager 0.28 inches on the football field, or 7.1 millimeters.
  • The Holocene era, or the age in which humanity rapidly grew to dominate the Earth, is even less geologically significant, having lasted about 11,650 years so far, which translates about 0.234 millimeters.
  • Recorded history begins with accounts dating back to roughly 3500 B.C.E., about 5500 years ago as of this comic's publish date; it would take up a width of about 111 micrometers. A human hair can be as thin as 17 micrometers, or as thick as 181 micrometers, so Megan's claim that all of human history can fit within the width of a human hair depends largely upon the sample being used.

Megan, a geologist, tells a story about how small the timespan of human history is compared to Earth's total history. She does this to juxtapose it with normal human time-scales, to imply that her being two weeks late turning in her project is immaterial by the standards of the Earth's tremendous age. She tries to sell this story to Cueball and Hairbun, but Hairbun's response does not seem to bode well for Megan.

Megan's delay of two weeks would map to about eight nanometers on the football field. The most powerful electron microscopes have a magnification of ten million, which would make it look like about eight centimeters (about three inches), so her statement about it being "too small to see even with a powerful microscope" is a bit of an exaggeration. The most powerful optical microscope has 6500x magnification,(New York Times, March 8, 2011) which would indeed be inadequate.

Randall states in the caption that this is a trick that geologists always try to use when being late turning something in.

In the title text, Hairbun and Cueball reply by turning Megan's own argument against her. They promise to pay her for her work in what could be considered a short amount of time on the geological scale - which could easily be many, many times longer than Megan's own lifespan. Megan, like all working people, wants to be paid in a timely manner for her work,[citation needed] and would be deeply dissatisfied to have her payment delayed for so long. Thus, Hairbun and Cueball's rebuttal proves a point: when other people require you be punctual, it's easy to dismiss them as just being impatient; when you're the one who needs other people to be punctual, it's not so easy to criticize yourself.

The comparison with a football field is a typical, but doubtful practice to explain people what the size of an area is (1257: Monster). Here it is used as an analogy with a one-dimensional timescale.


[Megan, arms spread out, is delivering a long-winded explanation to Hairbun and Cueball.]
Megan: Imagine Earth's history as a football field, from the planet's formation at one end to today at the other.
Megan: Complex life would be largely limited to the final ten yards. Dinosaurs appear at the five-yard line, the age of mammals happens in the last 1½ yards, and humans arise in the final few millimeters.
Megan: All of written history would fit in a strip narrower than a single hair.
Megan: "Two weeks" would be too small to see even with a powerful microscope.
Hairbun: Mm hmm.
[Caption below the panel:]
Geologists always try this when they're late turning something in.

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Football pitches don't have five-yard lines… (talk) (please sign your comments with ~~~~)

You pitch a baseball, not a football. (talk) (please sign your comments with ~~~~)
Yes and in the comic it does say Football field. And Randall is known for not knowing anything about sport, so he may project this onto the geologist and not let her know about the five yard line... --Kynde (talk) 20:26, 9 August 2019 (UTC)
And at the risk of being picky, I'm sure Randall is talking about an American football field, which does have five-yard lines. They just don't have a label on the field, which is only the ten-yard lines, but there is a line across the field every five yards. Ianrbibtitlht (talk) 00:05, 10 August 2019 (UTC)
I agree that Randall is definitely referring to NFL-style US Football in this comic. Also, since the US women's 'futbol' team won the world cup, we're officially calling it 'Soccer' until someone wins the championship back from us.  ;S
ProphetZarquon (talk) 11:28, 10 August 2019 (UTC)
Agree it is a American Football field (as we call it abroad, also you do not use your feet much to kick the ball compared to Soccer). Do Woman play football? I believe most people who actually care about football do not care for the Womans futbal :-D By the way I don't care for sport, almost on the same level here as Randall, and also I did not know that there were a 5 yard line on an American Football field, but all the time assumed it was. As far as I know there are no distance lines on a regular real football field (soccer field to you). --Kynde (talk) 10:09, 11 August 2019 (UTC)

Should we have a geology category, like we have Category:Geography and many other science categories? --Kynde (talk) 20:26, 9 August 2019 (UTC)

Just realizes I could easily find more than 10 comics that would fit into that category, so I have created it: Category:Geology

This reminds me of The Cosmic Calendar from Carl Sagan's "Cosmos" TV Series. https://www.youtube.com/watch?v=Ln8UwPd1z20 Gpg (talk) 20:29, 9 August 2019 (UTC)

The title text reminds me of a cartoon I once read where these two guys talk to God hidden in the clouds. Guy: God is it true that a million years feel like a minute to you? God: Yes my son. Guy: Is it also true that a million dollars would be like a dime to you? God: Yes my son, that is true! Guy: God, could you spare a dime for me? God: Yes my son, in a minute. :-D --Kynde (talk) 21:10, 9 August 2019 (UTC)

What does anything in this comic mean? Asking for… absolutely everyone in every single country except the USA. Fabian42 (talk) 09:38, 10 August 2019 (UTC)

I think there are a few people outside the USA who understand yards and feet, and even what an American football field is. Catherine (talk) 10:29, 10 August 2019 (UTC)
Sure, but very few outside the USA have an intuitive feel for what the actual relative sizes are except for "a football field is probably pretty big and a microscope can see very small things". So outside the USA it's an analogy that is less useful than just saying the time in years. Fabian42 (talk) 13:22, 10 August 2019 (UTC)
A regular football field and an American football field is almost the same size and a yard is close to a meter. I'm pretty sure than 90% of those coming here did understand the analogy in this comic, and the other 10% was probably from the US ;-D --Kynde (talk) 10:09, 11 August 2019 (UTC)
To be clear, as a North American, I only use and approve of the name "soccer" because it's simpler for differentiating from what we call football, soccer clearly SHOULD be called football, it primarily uses the feet, LOL! Like I just said a few days ago on a Facebook post, the rest of the world should call American Football "soccer", just to complete the confusion, LOL! Anyways, thus I'm using the word soccer vs. football here: I THINK a soccer field is quite a bit bigger than a football field, at least they look MASSIVE when I see televised games (like the World Cup). In less professional situations - like if me and my friends went to play an informal game - yes, we'd use the same field. American Football is 100 yards long (50 per side), Canadian Football is 110 (55 per side). So, mentally divide a soccer field ("football pitch") into 100 parts to get a yard. :) So dinosaurs are 5/100ths of a pitch. NiceGuy1 (talk) 05:20, 15 August 2019 (UTC)

Everyone who cares already knows, but I feel obligated to point out that dinosaurs did not go extinct at all, contrary to the article's assertion. Nitpicking (talk) 02:36, 28 June 2023 (UTC)

Please use the metric system in your explanation. Randall does not approve of imperial units.[edit] 14:52, 12 August 2019 (UTC)

He wouldn't touch the imperial system with a 3.048 meter pole Whereisspike (talk) 17:21, 12 August 2019 (UTC)

Seems to make more sense to use imperial about this comic that talks in imperial measurements. Well, a mix. :) "Yards" ARE ubiquitous and thoroughly entwined with football. NiceGuy1 (talk) 05:20, 15 August 2019 (UTC)
Mainly using your hands make it not football. Hands = handball.