
How Insects Breathe - srikar
http://noticing.co/how-insects-breathe/
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todd8
One reason insects breath differently than we do is that the surface to volume
ratio between us is so different. Naturally, volume increases as the cube of
the linear dimensions of the organism and the surface area only increases as
the square of the dimension. This means that the ratio S/V is directly
proportional to the size of the organism. A mouse has a much lower terminal
velocity when falling than a human, for example, because they have a higher
surface to weight ratio (weight of course is related to volume). Insects are
so small that breathing doesn't require the mechanisms that we require because
their S/V ratio is so so much larger. On the other hand, desiccation is a much
greater problem for insects as is surface tension when wet. For these reasons,
insects often have waxy coatings or other means of protecting themselves from
drying out or being trapped in by a water drop, but an ant doesn't have to
worry about falling out of a tree.

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scott_karana
Surface/volume ratios are responsible for a lot of other things in nature,
like the size/metabolism of mammals compared to the mean temperature of their
habitat. (Eg, even within the same species, larger specimens are typically
from colder climates)

EDIT: go figure, they have a related article: [http://noticing.co/on-size-and-
metabolism/](http://noticing.co/on-size-and-metabolism/)

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aatish
Yup, we also have another post that's specifically about the idea you
describe: [http://noticing.co/on-size-and-warmth/](http://noticing.co/on-size-
and-warmth/)

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aatish
Hi, I'm one of the authors of the piece. Thanks for voting us up here. Hope
you like what we're doing, and let us know what you think. If you're looking
to read more of our posts, you can follow the blog on twitter @noticingblog
(or on RSS). Cheers.

~~~
solutionyogi
Your website is extremely well done.

1\. Great typography. 2\. Useful illustrations and 3\. A great single column
layout, which is easy on the eyes. 4\. No annoying popups asking me to
subscribe to mailing list. 5\. Loads super fast.

And to top it all, the actual content is amazing. I am subscribed!

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gPphX
* your persistent banner is thoughtless

* AdBlock : noticing.co##HEADER.site-header

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bhritchie
If you enjoyed this, you will probably also like J.B.S Haldane's essay, "On
Being the Right Size": [http://irl.cs.ucla.edu/papers/right-
size.html](http://irl.cs.ucla.edu/papers/right-size.html)

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dmalvarado
So, are the conclusions based on science? Not speculation or correlation re:
size of insects and oxygen density. 35% oxygen to 21% doesn't seem to account
for a millipede going from 8 feet to 15in.

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forgotmypassw
The oxygen level is only a single factor here, there are probably many more
that influenced the size.

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JumpCrisscross
There's compelling evidence for a causal link. Hundreds of millions of years
ago the atmosphere was much more oxygen-rich than it is today. Insects were
also far bigger.

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krishicks
I enjoyed the piece. It felt like reading an episode of RadioLab.

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merpnderp
I guess this explains why you don't need to buy expensive and dangerous wasp
spray. A squirt bottle with a thick mixture of soap will kill them in seconds
by cutting off their ability to breath.

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Broken_Hippo
I wish at least beginning science and math books had been written like this :)

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transfire
Given that there are various ways to breath, I wonder if an artificial means
might ever be substantially more efficient than natural lungs?

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amelius
Nicely done. I would love to see such a schematic for fish too.

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Amorymeltzer
The circulatory systems of different creatures would be neat to see. Frogs
have a weird, sponge-like heart, for example, and plenty of little critters
have their entire bodies filled with "blood."

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IceyEC
Oh my god that header is huge

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kqr
I agree; it didn't work well on a half-small browser window. Either make it
even smaller and the header goes away automatically, or open the JavaScript
console and run

    
    
        jQuery('.site-header__wrapper').hide()

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ckinnan
Interestingly, humans breathe in a second way not mentioned in the article.
The eye's cornea actually receives its oxygen directly, through the process of
diffusion. [https://www.quora.com/Do-our-eyes-
breathe](https://www.quora.com/Do-our-eyes-breathe)

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tomrod
This is incredibly well done. Kudos to the author for the attention to detail
and the informative read!

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fezz
What would happen if you bred insects in a 50% oxygen environment?

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nartz
What a great article!

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Sideshow_Boob
all the smugness of RadioLab mixed with the talking-down-to-ness of VOX.
Thanks, #content internet!

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BinaryIdiot
> [...] smugness [...] talking-down-to-ness

I read the entire thing and I didn't get the impression of either. In fact it
even said they didn't know for sure how the passive system works but that this
is one theory and then explain it.

Seemed like a good read overall and I didn't feel talked down to or anything.

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Camillo
This is for children, right? All of this stuff is taught in school.

