by Matthew Cobb
I was in the garden reading about Francis Crick and the genetic code (the way one tends to do at this time of year), when I noticed Pepper the cat staring intensely at something small on the ground that was moving erratically. I went over to see what was going on and discovered that he was looking at a greenbottle fly (Lucilia sericata), which had one wing still stuck in its golden pupal case. That accounted for the erratic movement – it was trying to fly away, but couldn’t for obvious reasons.
Feeling curious, I managed to remove the pupal case, and then brought the fly over to the table to see if its shrivelled wing would be pumped up and it would be able to fly. After 30 minutes, this was the result (iPhone 5 pic):
That wing is never going to inflate. This, I’m afraid, is a soon-to-be ex-fly. It will have expired. It will be pining for the dog crap. With only one wing, it’s a walk, not a fly, and it will either be eaten by one of the cats when they’re bored, or it will be snarfed by a bird or an arthropod predator. It seems very unlikely that it will be able to mate (and no, I can’t tell which sex it is).
That’s natural selection for you, but not evolution. It seems unlikely that the problem faced by this fly had a genetic origin (something just went wrong), and therefore the death of this fly will almost certainly have no effect on the future of the species. Unless, of course, you think that Ray Bradbury’s time-travel story about killing a butterfly in the past may have some credibility, in which case, who knows what may happen in an election in a few million years time…
He will have run down the curtain and joined the bleedin’ choir invisibile!
It will be stiff. Bereft of life, it will rest in peace.
But before that, it will be taunted with the cruel mocking of the other files with their perfectly inflated wings.
It’s an arthropod ; no matter how many joints it has, it’ll always be fundamentally stiff.
I love reading your small anecdotes Matthew, what a treat. 🙂
I wonder what was going through the fly’s head during its brief encounter with life on this planet?
Kitty’s teeth?
Hehe…maybe it was busy cursing its troublesome wing and never saw kitty coming.
I don’t know about this particular fly. But I do know what was the last thing to go through the head of the fly who got caught on my windshield the other day: his ass.
…sorry….
b&
No apologies necessary. 🙂
*slow clap*
Thank you, thank you. I’m here all week. And try the backstroke fly soup…though the last one had the fly going in circles for some unexplained reason….
b&
Sounds like my kind of soup…nothing like a small buzz during dinner.
Actually, I think it’d be more to Baihu’s taste than mine. I kid you not, a fly in my house has a life expectancy measured in single-digit minutes — and I don’t own a flyswatter nor subscribe to the paper!
b&
Maybe I should get a cat. The flies are a nuisance during the summer especially at night….damn hard to sleep with one buzzing around every other minute.
A cat or a couple of gekkos.
Yes, you should get a cat. Without question.
I’ve never seen a cockroach indoors, and I’ve only ever heard crickets…for about five minutes total. Crickets outdoors are fine, but one inside resonating in the living room will drive me insane. Fortunately, all I have to do is aim Baihu in its general direction, and a minute or so later the sound of chirping cricket will be replaced with crunching chewing cricket sounds — which, in turn, will soon be replaced with purring sounds. Now that I can live with!
b&
So this is what feline indoctrination feels like. Clearly Baihu has you under some kind of spell. 🙂
In all seriousness though, I am thinking about it.
Why stop at one when you can have a glaring?
I’m thinking one is plenty for my anti bug needs. Although I’ll probably end up a hoarder with 40sumthing cats and a pack of wild dogs.
I never know when to quit while I’m ahead.
Well, he is a god….
b&
A handsome specimen indeed. 🙂
And, perhaps not coincidentally, until an hour or so ago he was wrapped ’round my hand in the exact same position in the exact same spot, and he’s now on the exact same mentioned comforter….
b&
Actually a comment to your post one indentation further.
We have roaches and the occasional cricket. Our cat just sort of, shall we say, practices its philosophy of non-violence.
Might want to warn your cat…violation of §304.8712(b)(8)* of the Pan-Galactic Feline Code of Conduct can be serious business.
b&
Chameleon power?
Even better. Cat power!
b&
I thought the story was going to end with the cruelest of ironies: Matthew, in a flash of morbid humor, and a regular fly-not-eater, messily devours the fly, and then recounts to us the taste like ALton Brown might.
Maybe she just wanted to be a dancer. She told Pepper the cat obviously thinking Pepper could translate for you. Fly needed your help to realise her dream and share her talents with her children. Her beautiful colour, perfect hair, big sweet eyes and long think legs. You prevented a whole new race of dancing flies from evolving. She got your attention but you didn’t know what to do, we don’t blame you.
This is wonderful, that’s the stuff scientific papers were made of once. But hang on… When you say: “the death of this fly will almost certainly have no effect on the future of the species”, what if this particular fly happened to be the only carrier of a particular new smarty-pants allele that originated precisely in the germline progenitor that gave rise to her. Then the allele would be lost from the population, and the future of the species would look different…
All it needs is an iterested male greenbottle – many moths have wingless females. A wingless male would never find a mate though.
You can tell the sex – this is a female I think. No, I am not looking at its nadgers – the male has slightly natrrower gap between the eyes – perhaps the eyes are bigger.
Question – how soon after emerging can a female dipteran – fruitflies, houseflies in particular – lay egges?
Are they already developed or does she need to have a bit of time & have them develop in her first.
And how long after mating before laying?
Anyone?
This is from orkin.com and isn’t the same in some ways as the information at Wikipedia. However, the Orkin page seemed more specific to answering most of your questions.
I think the biggest difference is that Wikipedia states 36 hours before mating for the female.
Hard to believe I can feel sorry for a fly … But I can turns out.
Exactly what i was thinking on reading this. Given our seemingly innate capacity for a level of human empathy, even toward these vile creatures, there may be hope for our species yet.
No offense, but I’m not so sure that you can, or that anyone can.
To feel sorry for the fly implies that we can empathize with it and imagine what it must be like to be a fly with a damaged wing. But the reality of what it’s like to be a fly (healthy or damaged) is almost certainly beyond our ability to imagine. Quite possibly it’s not like anything at all; perhaps a fly’s brain is just too small and simple to contain any sort of awareness of its own existence as a sentient being, let alone its impending doom.
If that’s the case — if flies are merely reflex machines with no sense of self — then our empathy is misplaced, and what we think we’re feeling sorry for is a fantasy.
I feel bad that the fly will have his fly experience doing fly things cut short.
But that’s just the question: is there any such thing as “fly experience”? I’m not sure there is, or that it’s of a sort to which being cut short makes any meaningful difference.
Should we feel bad that a broken toaster’s “toaster experience” has been cut short?
We shouldnt but we do. Could be something is wrong with my brain.
At what point then is any animal aware of its existence in your graded scale?
Yeah, and haven’t you seen the Brave Little Toaster!! 🙂
And who doesn’t remember the electrifying horror flick “The fork and the toaster”.
I can’t point to a hard cutoff; in fact I’ve said several times now that I’m not sure and it’s an open question.
But I’m not going to lose much sleep over bugs whose bug experience has been tragically cut short on my windshield. (And I suspect neither are you.)
I need to buy a new one and reading the reviews, I have no confidence that the new ones will be better than the mediocre performance of my old one when it was new.
I feel bad about my toaster’s toaster experience. It could have been great. It could have had it all.
Ah, but can a mere chemical machine not feel love when love is just a matter of chemicals?
Perhaps! 🙂
When I first heard of the Butterfly Effect, I assumed it was derived from the Ray Bradbury story (A Sound of Thunder)
I would have said that’s death, but not natural selection. Since selection is inherently statistical — the preferential amplification of some alleles over others in the gene pool — a single death cannot be inferred to be an instance of it. Only consistent trends over many deaths count as selection.
In Australia we would call that a blue-arsed fly.
Londoners too… but this one is green-arsed!
Green-bottles like this attack sick ducks and geese. They swarm all over the body feathers, and work their way down to the skin to lay eggs. I’m not too sure the attraction to sick birds, -almost certainly the smell. The birds do stop preening when sick which may be one of the factors, which goes to explain the furious preening of large birds. On rare occasions the goose will get better, and I assume will preen the maggots out of its feathers.
A greater point is that this deformed fly reminds one that so many common species have a high rate of deformity. With birds it is often in the form of failure in cerebral development whereby the chick will flap in an unco-ordinated way and not be able to fly. The very high rate of failure to develop, – as much as 20% of young, must surely be a factor in evolution. Any bright youngster, seeing all this around him or her, is halfway to understanding evolution. Just the mention of the word ‘evolution’ when I was about ten was enough for me to understand. And that led me to suppose that the religious mind has a deliberate disability, which I call ‘inability to process experiential information’. The religious mind deliberately discounts observation upon the real world. That idea opened a whole new understanding of religion. It is most definitely NOT indoctrination; it is an alternative (and very wrong) way of understanding the world.
“That’s natural selection for you, but not evolution. It seems unlikely that the problem faced by this fly had a genetic origin (something just went wrong), and therefore the death of this fly will almost certainly have no effect on the future of the species.”
Unless there’s some genetic variation in how the pupa casing opens, and how well it separates from the fly. I remember reading something analagous about arthropods molting where the authors hypothesized that one of the factors leading to trilobite extinction was that they got stuck inside their old skins more often than other species. They showed that modern arthropod exoskeletons typically open in the same way reliably, while fossils of trilobites showed a relatively large variability in where the exoskeleton opened.