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Comment by mewpmewp2 | Hacker News Reader

I understand when butterflies are standing by their wings wouldn't be that far ahead, but is it the case also when they are flying? That is not so clear to me. When flying it seems there can be a lot of variance where their wings can be.

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There is quite a variation in its wing position while flying: https://www.youtube.com/watch?v=odvYot6Rldw&ab_channel=Earth... So at least some butterflies do actually move their forewings significantly forward of their head while in flight (as stated by edamstra on June 2nd, 2017 - comment on the OP link)

I took a look at some slow mo videos and midflight photos, and these were really interesting. In particular what seemed interesting is how in some videos they almost like swam through the air in which case they did extend their wings up front as if to grab air under it and then they brought them back down. So the animation on the web app is more static, but I don't think it's fair to call it a dead butterfly based on that. Also I think I now understand why there's a swimming technique called butterfly.

Seeing those slow mo videos and some of the images in the edamstra link I think it's a bit unfair to criticise some of the things like earrings etc, because with many of those it's very plausible they could be mid-flight moments (especially earrings as they are literally in the air).

And the "dead butterfly" shirt seems to be very aware and all of those could be same butterfly during its flight representing all the possible positions.

Butterfly can also refer anything open / wide-open.

The moment I saw the live vs. dead comparison it hit me: center of lift vs. center of mass. Why would the butterfly's wings ever project that far forward when there is zero mass out there to lift? I suppose it's not impossible -- maybe the butterfly is hard-braking? But in normal flight that just wouldn't work. I never thought about it like that before, but now I can't unsee it.

Out of curiousity I took a look at some midflight photos as well as slow mo videos. It could also vary by butterfly type, but there were definitely midflight photos were I saw wings quite extended front. Also in slow mo it almost looks as if they are swimming through air where they extend wings front to grab air and bring them back down. I suggest taking a look at some slow mo videos. It now occurs to me why there's a swimming technique called butterfly. The animation in the web app doesn't do the swimming technique justice, it's rather static, but at least I do think at certain point they have their wings quite extended, so unless you animate this whole thing, I don't think it's as fair to call it dead compared to if it's standing by with wings extended.

That's fair -- to something as small as a butterfly the air is much more soup-y, so swimming is maybe a better description than flying. That would imply they do need to extend forward beyond their head to pull forward through the air.

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