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How many flies are in my apartment?

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Re: How many flies are in my apartment?

#121

Post by grahamburger »

layoutIfNeeded wrote: post #114
grahamburger wrote: post #112

Earlier quoted context omitted.

Another fun thing you can do with flies, and also bees and wasps, apart from vacuuming them up, is put them on a leash. But first you have to freeze them. Catch one in a cup or plastic bag and stick it in the freezer for about 10 minutes. When you take it out it will look dead, but it's not (unless you leave it in too long.) Being careful not to rip it's wings off, tie a small string or fishing line to one of it's le…

That’s animal abuse.

Where would you say it falls on the spectrum of animal abuse in relation to going fishing, fly swatting, and walking the dog? Those are all activities I'm personally ok with.

Re: How many flies are in my apartment?

#123

Post by JadeNB »

lolc wrote: post #34

All these models ignore how insects actually zero in on a smell. For a fly outside, the source of the smell is the gap in the window. What looks like random direction changes is actually a search pattern for that source.

> All these models ignore how insects actually zero in on a smell.

It seems to me that the author is not ignoring that:

> While the flies now obey the laws of aviation, there's still something that seems missing. Normally, flies want to get indoors. They need to get indoors. So to simulate this, I added an attractor (maybe a rotting piece of fruit) at a position A indoors to lure the flies.

Re: How many flies are in my apartment?

#124

Post by Slump »

mig39 wrote: post #89

Really interesting work. I love the different models of how a fly moves around. This jumped out at me, though: >If we take a look at the animation now, we can see the flies look slightly more realistic (if not still a bit spazzy) Is "spazzy" a word that's used in different regional dialects of English as a term to just mean jittery? In most of the places I've lived, it's an offensive word.

I've only heard it used as a synonym to "jittery" or hyper-active in my region of the states (mid-west). Good to know it's considered offensive in places, not that I really use the word. I had a colleague in school that had the nickname of "spaz". Mostly it was used ironically because they were super laid back all the time.

Re: How many flies are in my apartment?

#125

Post by morelisp »

OJFord wrote: post #120
morelisp wrote: post #77

Earlier quoted context omitted.

I had a friend kicked out of a cafe once for killing a wasp because they didn't want to deal with the situation if the Ordnungsamt was walking by or something. Wasps are the usual example because it's legal to kill flies/mosquitoes and no one wants to kill the other protected insects like bumblebees. The wasps in Berlin are common and pretty aggressive, and have free rein in an awful lot of the chain backeries.

Interesting, but are they justified in that fear do you know? What I mean is, if this is a commonly believed exaggeration then it could just be that in this case the person believing it wasn't the wasp-killer (or would-be-killer) but the cafe owner. Has your friend ever actually been fined for doing it, or did the cafe owner/manager mention having had to deal with it in the past? Certainly does seem odd that this law…

I doubt anyone has been fined the full value just from killing one wasp from some random fine. It is regularly enforced against people who try to burn down or otherwise remove nests on their property (without engaging a professional to try to remove it safely for both parties).

I would say mainly it's not enforced because b) has been effective - Germans (or Berliners at least) don't kill wasps! If doing so became common, it would probably be enforced more consistently.

Re: How many flies are in my apartment?

#126

Post by marcosdumay »

m12k wrote: post #54
rozab wrote: post #47

Earlier quoted context omitted.

Fun idea, but presumably there is a big bias in that some flies will be easier to catch for various reasons. I suppose lots of population studies on birds, cetaceans or whatever have this bias, since you can't just slap a quadrat down and catch everything. In fact with these more advanced animals, perhaps they're harder to observe a second time since they've learned to be wary of humans.

Right, if you're measuring long enough that predators eating some of the flies could be an issue, then you'd want to mark them with something only visible under a blacklight, or similarly "neutral", so it doesn't introduce a bias.

If predators or age (or moving out or into the measured area) are a factor, they are already biased and keeping your method neutral will still give you very wrong results.

Re: How many flies are in my apartment?

#128

Post by Andrew_nenakhov »

paul_manias wrote: post #101
Aeolun wrote: post #76

Earlier quoted context omitted.

I found two flies in my house, marked them, then later found two more flies without marks. I think this means the population of flies in my house is infinite.

This reminds me of the time I found two flies in my house despite the windows being closed. I vacuumed them up (more fun that way) and the next day there were two identical looking flies in the house. Did they get out of the vacuum cleaner? I vacuumed them up again. The next day, same story. The flies were now appearing throughout the day. They all looked the same. Where the hell were they coming from? The windows we…

I admire your perception. I'm personally unable to distinguish different fly specimens, they all look the same to me.

Re: How many flies are in my apartment?

#130

Post by lolc »

JadeNB wrote: post #123
lolc wrote: post #34

All these models ignore how insects actually zero in on a smell. For a fly outside, the source of the smell is the gap in the window. What looks like random direction changes is actually a search pattern for that source.

> All these models ignore how insects actually zero in on a smell. It seems to me that the author is not ignoring that: > While the flies now obey the laws of aviation, there's still something that seems missing. Normally, flies want to get indoors. They need to get indoors. So to simulate this, I added an attractor (maybe a rotting piece of fruit) at a position A indoors to lure the flies.

The model where the fly knows where the source of the smell is located the weird outcome of the flies targeting the pane in the middle instead of the sides where the smell escapes.
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