Sciency Words: Preservation Bias

Hello, friends!  Welcome back to Sciency Words, a special series here on Planet Pailly where we take a closer look at interesting and new scientific terms in order to expand our scientific vocabularies together!  Today’s Sciency Word is:


So is there life on Mars?  Well, there could be.  It’s not totally impossible.  But as I’ve said before on this blog, I think the odds of us finding living things on Mars are pretty low.  The odds of us finding dead things on Mars, however… I think those odds are much better!

Or at least I did think that until I read this paper, entitled “A Field Guide to Finding Fossils on Mars.”  That paper introduced me to the concept of “preservation potential,” and subsequent research led me to learn about something paleontologists call “preservation bias.”

Basically, turning into a fossil isn’t easy.  A lot of factors have to come together just right in order for a dead organism to become preserved in the fossil record.  As that Martian fossil field guide explains:

On Earth, most organisms fail to fossilize because their remains are physically destroyed, chemically oxidized or dissolved, digested by their own enzymes, or consumed by other organisms.  Fossilization only occurs when processes of preservation outpace degradation.

Preservation bias refers to the fact that certain organisms—or certain parts of certain organisms—stand a better chance of fossilizing than others.  Preservation bias can also refer to the fact that some environments (rivers and lakes, for example) do a better job creating and preserving fossils than others (for example, deserts).

A lot of factors can get involved in this, but as a quick and easy example, think of the dinosaurs.  Dinosaur bones fossilize easily enough.  Other parts of the dinosaur… not so much.  That, my friends, is preservation bias at work, favoring hard tissue, like bone, over soft tissue, like muscle or fat.

Now imagine what would have happened if dinosaurs somehow evolved without bones (that’s a weird concept, I know, but just bear with me a moment).  How much would we know about those boneless dinosaurs today?  Would we know about them at all?  Those hypothetical boneless dinosaurs could have roamed the earth for billions of years and left hardly a trace of evidence for us modern humans to find!

Which brings us back to Mars.  There was a time, very long ago, when Mars was a much warmer and wetter planet than he is today.  It’s possible—no, I’d say it’s probable!—that life of some kind developed on ancient Mars, just as it did on ancient Earth.  But would that ancient Martian life have left us any fossils to find?  Maybe.  Maybe not.  It depends on the various factors involved in preservation bias.

P.S.: Boneless dinosaurs are delicious.

Atomic Love

A single atom of love may not seem like much.  By definition, it is the smallest quantity of love that could possibly exist.  And yet, just like a real atom, even a single atom of love contains within itself tremendous amounts of power.

P.S.: Quantum physics fans may enjoy knowing this: the background for today’s drawing was done using a color called “Copenhagen blue.”

Sciency Words: Safety Ellipse

Hello, friends!  Welcome to Sciency Words, a special series here on Planet Pailly where we talk about those wild and crazy words scientists use.  Today’s Sciency Word is:


I don’t know about you, but when I’m trying to dock my shuttle pod with another spaceship, I like to take a few long, leisurely loops around that other spaceship first.  You know, like this:

Spaceships are pretty!  Who wouldn’t want to get a good look at them from every conceivable angle before completing docking maneuvers?  But it turns out that circling round and round a spaceship like this is not just for admiring the view.  It’s also for safety!  As explained in this paper:

A “safety ellipse” is an out-of-plane elliptical periodic relative motion trajectory around the primary spacecraft such that the trajectory never crosses the velocity of the primary.

That clear things up?  No?  Okay, how about a quote from this paper instead:

This paper defines a safe trajectory as an approach path that guarantees collision avoidance in the presence of a class of anomalous system behaviors.

Still confused?  Here’s a short video demonstrating what a safety ellipse (a.k.a. a safe trajectory) looks like:

Basically, if your shuttle pod experiences engine failure or any other major malfunction, flying in a safety ellipse ensures that you will not collide with the ship you were trying to dock with.  At least not for a good, long while.

I first heard about this term the other day while watching the livestream of the SpaceX Dragon capsule approaching and docking with the International Space Station.  Several times, the livestream commentators mentioned that Dragon was utilizing a “24 hour safety ellipse” or “24 hour safe trajectory,” meaning that if anything went wrong, mission control would have at least 24 hours to fix it before Dragon and the I.S.S. collided.

So remember, friends: the next time you’re going to dock with another spacecraft, do that out-of-plane elliptical periodic relative motion thing.  In other words, circle around the other ship a few times before making your final approach to dock.  It’s for safety reasons.

P.S.: It’s also for enjoying the view.  Spaceships are pretty!

No Gospel Truth in Science

Hello, friends!

So there’s this notion in the popular press that when a new scientific paper comes out, that paper should be taken as the final definitive word on an issue.  Science has spoken.  This is a scientific fact now.  But that is not how science works.

When new research is published, you should expect there will be followup research, and then that followup research will be followed up by even more research.  A new scientific paper really shouldn’t be seen as a proclamation of fact but rather as the beginning of a dialogue among scientists, or perhaps as the continuation of a dialogue that’s already in progress.

The recent detection of phosphine in the atmosphere of Venus has turned out to be a fantastic example of this ongoing dialogue in action.  The initial research was published in two separate papers (click here or here).  Basically, astronomers found the spectral signature of phosphine (PH3) in the Venusian atmosphere, and they were at a loss to explain where all that phosphine could be coming from.

Based on everything we currently know about Venus, those two papers tried to rule out several possible explanations.  Such a large quantity of phosphine could not be created by Venus’s atmospheric chemistry.  It could not be spewing out of volcanoes on Venus’s surface.  It could not be delivered to Venus by asteroids or comets.  One very intriguing possibility that could not be ruled out: maybe there’s life on Venus.  On Earth, phosphine is produced almost exclusively by living things.

But those two papers were not the definitive final word on the matter.  A dialogue had begun.  Soon, followup research came out suggesting that phosphine could be spewing out of volcanoes after all.  It would still be pretty shocking to discover that Venus has enough active volcanoes to produce that much atmospheric phosphine—but it be nowhere near as shocking as discovering Venus has life.

And then even more followup research came out with this paper, which points out possible errors in the original research and suggests that we may be dealing with a false positive detection.  Venus might not have phosphine after all, or maybe it doesn’t have as much as originally believed.

And the dialogue continues.  More research will come.  More responses will be published, and then there will be responses to those responses, and so forth until the scientific community reaches some sort of consensus about this Venusian phosphine business.  And even then, that scientific consensus still might not be the 100% final word on the matter.

Based on the way the popular press reports science news, you could easily get the impression that scientific papers should be treated as gospel truth.  You would be understandably confused, then, when one scientific paper comes out refuting the findings of another.  Subsequently, you may come to the conclusion (as a great many people apparently have) that science must not know anything at all.  Science just keeps contradicting itself, it seems.

But scientific papers are not meant to be taken as gospel truth.  They’re part of an ongoing back-and-forth dialogue.  So the next time you hear about some new scientific discovery on the news, remember that scientific papers are not intended to be bold proclamations of fact.  And when you hear about some new paper refuting older research, you’ll understand what’s going on.

Sciency Words: Data

Hello, friends!  Welcome to Sciency Words, a special series here on Planet Pailly where we talk about science and science-related terminology.  Today on Sciency Words, we’re talking about:


Okay, are you supposed to say “this data” or “these data”?  Are you supposed to say “the data is” or “the data are”?  In other words, are you supposed to treat “data” like a singular or plural noun?

Well, before I answer those questions, let me tell you something about English grammar that you already know, even if you don’t know that you know it.  English makes a grammatical distinction between count nouns (like shoe, child, or cactus) and mass nouns (like corn, furniture, or homework).

Count nouns have different singular and plural forms (shoe/shoes, child/children, cactus/cacti).  Mass nouns do not.  When was the last time you heard someone walk into a room and say, “Oh, look at all these furnitures”?

Traditionally, data has been treated as a count noun, with datum as the singular form and data as the plural.  This is consistent with the word’s Latin origin.  In Latin, datum meant something like “a thing that is given,” and so data would mean “things that are given.”

But of course, Latin is a dead language; English is still living, and in living languages words change.  Right now, “data” is in the process of changing from a count noun to a mass noun.  If I had to guess, I’d point the finger at personal computers for causing this change.  I imagine datum and data were once rather esoteric, rather academic words.  Then personal computers put the word “data” into the vocabulary of the masses—but not the word “datum.”

I mean, given how much (how many?) data computers process, how often would anyone need to talk about a single datum?  In our daily experience, a single bit of data is akin to a single grain of sand.  And so, much like the word “sand,” many of us have started treating “data” as a mass noun.  Those who still use “data” as a count noun are in the minority.

A few years ago, the statistics blog Five Thirty Eight conducted a survey asking, among other things, if people preferred “the data is” or “the data are.”  As Five Thirty Eight explains:

To those who prefer the plural, I’ll put this in your terms: The data are pretty conclusive that the vast majority of respondents think we should say “data is.”  The singular crowd won by 58 percentage-points, with 79 percent of respondents liking “data is” to 21 percent preferring “data are.”

There are still some contexts where saying “this data” or “the data is” would be frowned upon.  Basically, the more academic a setting you’re in, the more countable (and less mass-able) your data should be.  Although I’ve noticed that even the most persnickety of academics are more likely to talk about a singular “data point” rather than use the word “datum.”

Of course, none of this matters if you’re talking about Commander Data, the character from Star Trek.  In that context, Data is a proper noun, and therefore a countable noun, and therefore:

What Color are All the Planets?

Hello, friends!

So as you know, Earth is “the Blue Planet” and Mars is “the Red Planet.”  By my math, that leaves us with six other planets in our Solar System that don’t have color-related nicknames.  Today, I’d like to try and fix that.

Jupiter was the toughest.  He’s actually lots of different colors: red, grey, white, orange… and then the Juno mission recently showed us that Jupiter’s polar regions are blue!  Of course Jupiter is most famous for being red in that one specific spot, but even the Great Red Spot changes colors from time to time, fading from red to pink to white before turning red again.

Anyway, those are my picks for the color-related nicknames for all the planets.  Do you agree with my picks?  Disagree?  Let me know in the comments below!

Word Up!

Hello, friends!  Just sharing some artwork today.  I originally named this one “Climbing Word Count,” but then I realized “Word Up!” was a better name.  I think anyone who’s a writer can understand what this one’s all about.

10 Ridiculous Scientific Names

Hello, friends!

Sorry, I don’t have a Sciency Words post for you this week.  I was researching a thing, but it turned out that I’d bit off more than I could chew.  I really don’t think I should do a blog post on a topic when I understand that topic so poorly.

If you really had your heart set on learning some scientific terminology today, please check out this video from SciShow on some of the “ridiculous” names scientists have given to animal species.  Though personally, I’m not sure what they mean by ridiculous.  Han solo sounds like a perfectly sensible genus/species name to me.

#IWSG: My Love/Hate Relationship with Writing

Hello, friends!  Welcome to this month’s meeting of the Insecure Writer’s Support Group, a group that supports writers who might feel a little insecure about their writing.  If you’d like to learn more about IWSG and see a list of participating blogs, click here.

This may be one of the hardest thing for people to understand: sometimes, two mutually contradictory statements can both be true.  Here’s an example.  I love writing.  Also, I hate writing.  Let me unpack what I mean.

First off, I really do love writing.  It’s the single greatest source of joy and pleasure in my life.  Being something of an ethical hedonist, I’ve been trying for years now to maximize the joys and pleasures of my life.  In other words, I’ve been trying to squeeze more writing time into my schedule (as well as more time for other sources of personal joy, like drawing and reading).

I cannot take full credit for this pun.  Versions of this have been circulating the Internet for years.

In order to keep maximizing my writing time, I’ve slowly been transitioning from writing as a hobby to writing as a career.  But (this is the tricky part) if writing is my job now, if I’m not writing purely for my own amusement anymore, then I have to set a production schedule.  I have to deal with word count quotas and deadlines and other boring stuff like that.

And when I’m up against a deadline (self-imposed or otherwise), it tends to stunt my creativity and spoil my fun.  Writing starts to feel like a chore.  I am not at my writerly best when writing feels like a chore.  I don’t want to do it anymore.  All of a sudden, I hate writing.

It really are the deadlines that ruin writing for me.  Case in point: I’m writing this IWSG post well in advance of IWSG day, rather than scrambling to get it done the night before.  And I feel like this is turning out to be a much more expressive and honest post than what I typically write for IWSG.  Or at least, I feel a lot happier with this post than I normally do.

But if I want to make a career out of writing (and I do!), then I will have to learn to accept the bad with the good.  I have to learn to live with this tension in my writing life: I love writing, and also I hate writing.  I’m not really looking for advice here, by the way.  I am merely acknowledging to myself and to you that this is the way things are, and I’m trying to be very zen about the whole situation.

So this is what the writing life is like for me.  Perhaps some of you, my fellow insecure writers, understand what I’m talking about.


Hello, friends!  Just wanted to share some artwork today.  This is a bookwyrm.  As you know, most dragons hoard gold, but this one hoards literature.  Perhaps some of you can relate.