Drosophila, exponential growth, and the power of evolution

A few weeks ago I blogged about the way the universe is doomed by the exponential growth in readership of an old post here on Scientist Sees Squirrel.  That exercise was a bit silly, but I used it to make a non-silly point or two about biology.  My blogging example reminded me that I used to use an almost-as-silly fruit fly example in my undergrad ecology courses. I thought you might enjoy it – so here it is. (And if you’re teaching, and want to borrow it, be my guest.)

Imagine that you return from the grocery store with some bananas.  Unbeknownst to you, a single (inseminated) female fruit fly* has stowed away in there.  If all her offspring survive, how many fruit flies will your kitchen have after just one year?

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The blog post that dooms the universe

Warning: silly.

Got your attention, did I?

You know what got mine?  Noticing, a while ago, the apparently inexorable growth of interest in what I thought was a fairly dull* post, Friends Don’t Let Friends Use “cf.”, first published here in June 2016.  That post got a bunch of views when I first posted it, which isn’t unexpected.  Then it was largely ignored for a year or so, which isn’t unexpected either.  Then something odd happened: exponential growth.

That’s what’s shown in the graph above: month-by-month readership statistics for Friends Don’t Let Friends Use “cf.”.  It’s a lovely curve, isn’t it?  Let’s ignore the first year (which is dominated by novelty; every post gets a spike when first published).  Let’s make a semilog plot of the remainder, because that seems right for a curve like that.  And let’s fit a line to that semilog plot, because we’re scientists and we like to do that kind of thing.

There’s no such thing as “an unrelated genus”

 Image: Osmia rufa, André Karwath, CC BY-SA 2.5; Boletus edulis, Hans Hillewaert, CC BY-SA 4.0; Volvocales, Aurora M. Nedelcu, CC BY 2.5; Chimp, Aaron Logan, CC BY 2.5; Ranunculus asiaticus, Leif Stridvall, CC BY-SA 2.5; Isotricha intestinalis, Agricultural Research Service/USDA CC 0; Compilation, Vojtěch Dostál, CC BY-SA 2.5.

 (My writing pet peeves, part 4)

There I was, at the physiotherapist, reading a new manuscript by a friend and collaborator to distract myself from the indignities being visiting on my calf.  There I was, thoroughly enjoying what I was learning, when I was brought up short by a construction that drives me up the wall:

“this species, therefore, cannot be not congeneric with A. jonesi.  Instead, it actually belongs to Ethereum, a similar but unrelated genus”.*

 I gasped.  Unrelated?  No two genera on Earth are “unrelated”.  There are closely related genera and distantly related ones, but because all life on Earth shares a common ancestor, there are no unrelated ones.

Fisher’s geometric model of software updates

Images: Fisher’s model visualization, own work; update progress bar by Jeff Attaway, somewhat dubiously CC BY 2.0.

Last month, the Toronto Star newspaper launched a “new and improved” website, which is nothing short of awful. The other day, the only game app I keep on my phone pushed an update, and now it’s noticeably harder to use than it was before. I’m nursing my laptop along because Windows 8 and Windows 10 are both worse than Windows 7. Why do “updates”, “upgrades”, and “new and improved” products so often seem worse than what they replace?

R.A. Fisher knew*.

Science fiction, stone plants, and the certainty of improbable things

Image: Lithops stone plant, UNB greenhouse, © Stephen Heard

I love used-book sales. A little while ago I went to one at a local church, where I was amused to find all the science fiction on the children’s table*. I didn’t ask why they’d sorted it there, but I can guess, because I’ve always read a lot of science fiction and I’ve gotten used to it being routinely dismissed as beneath the dignity of serious readers. The knock is frequently that it’s just not believable: methane-breathing aliens, intelligent gas clouds, galactic civilizations, and planet-sized toroidal starships are all so improbable that they’re for childish play, not adult attention.

But I’m a biologist, and that means I know a bit about improbability. Let me tell you, as improbability goes, science fiction has nothing on nature.

Is biology beautiful?

Photo: Glasswing butterfly, probably Greta oto, on Asclepias curassavica; Eddy Van 3000 at flickr.com CC BY-SA 2.0

We could quit now, with our eyes on that glasswing butterfly: of course biology can be beautiful. Birds of paradise, lynx, ladyslipper orchids, Spanish moss*, orcas; can there be any doubt? But that’s not really what I mean. Is biology as a science beautiful, the way math is beautiful, and physics is beautiful?