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Why Elephants Don’t Explode: How Nature Solves Bigness (noticing.co)
178 points by aatish on Sept 2, 2015 | hide | past | favorite | 56 comments



This is why the largest animals in the world live in the sea: it's a better cooling system!

Also, for those interested to know more, I recommend looking up Geoffrey B. West's stuff on complexity. It mentions the same things as this article and puts them in a wider context:

https://www.youtube.com/watch?v=DFFVSvAr7Wc


I seem to recall an interesting anatomical feature in a whale's mouth or tongue, highly vascularised, whose function isn't fully understood. One thought I've had is that this is a heat-transfer interface, and part of the whale's temperature regulation system.

Whales consume prodigious amounts of energy, and that is largely trapped within its body mass. I suspect that thermal management is actually a fair part of their design challenge. Even humans in fairly cool water can have difficulty keeping sufficiently cool, and experienced long-distance open-water swimmers have died of heat exhaustion in warm water (a case occurred in the Middle-East a few years back).

PS: love Geoffrey West (and the rest of the Santa Fe Institute crowd).


> it's a better cooling system!

Anti-gravity support system too.


Note to self: when macbook gets too hot, submerge in ocean.


I used to go outside and sit my laptop on the snow when it used to get too hot.

It... sort of worked. It cooled the laptop. Performance was discernibly better.

Until one day water (melted snow) got in and laptop stopped working. Totally serious, this happened.


Haha :) Before I retired it, I sometimes put my Asus Eee netbook in the fridge to cool it down. Somehow I managed to avoid getting ice inside the chassis. Pure luck probably :)


Probably not the way you want to sink your laptop :-)


The Sauropoda did not live in the sea as far as we know it.


The heaviest estimates for modern sauropod reconstructions are way short of blue whales, roughly in the range of fin whales.


Still, I think the point is somewhat valid, if for nothing but curiosity.

The largest dinosaur, which I know is a subject of discussion, is https://en.wikipedia.org/wiki/Argentinosaurus 30 metres, 80-100 tonnes and blue whale https://en.wikipedia.org/wiki/Argentinosaurus 30 metres, 180 tonnes

If a 100 tonnes creature can live on land, my gut tells me a 180 tonnes creature could too. where's the point of no return? There's all sorts of cooling mechanisms that could be dreamt up, just as we see strange heating mechanisms (https://en.wikipedia.org/wiki/Stegosaurus#Plates).


True, but at that point we're comparing warm-blooded mammals to... well, we don't really know, do we? But it's very possible they could simply slow down their metabolism even more than mammalian megafauna.

https://en.wikipedia.org/wiki/Physiology_of_dinosaurs#Metabo...

https://en.wikipedia.org/wiki/Gigantothermy


TLDR:

If you burrow down — all the way down — to a typical cell in an elephant, and then compare it to a typical cell in a mouse — amazingly, the two cells behave differently.

Elephant cells aren’t lazy. They’re always working, but compared to mouse cells, elephant cells typically do their job a little more slowly, burn less fuel to get the job done and, being more efficient, they run cooler.*

So that’s why elephants don’t spontaneously combust (and neither do we, much to Calvin’s relief.) An elephant is built from cooler stuff than a mouse. Even though an elephant has many, many more little heaters packed inside its body, each heater runs at a much lower setting.


Calvin's, Benson's and Bassham's relief -- I presume?


Reminiscent of JBS Haldane's Classic essay "On Being The Right Size", which I recommend to anyone who liked this. http://irl.cs.ucla.edu/papers/right-size.html


Robert Krulwich has such an amazing way of explaining things. It takes almost no time to recognize his writing.


Really enjoyed this - interesting read with awesome illustrations and interactivity. Also love the Noticing.co name (bookmarked).


Of course. For small animals, life is a struggle to keep warm. For large animals, life is a struggle to cool off.


For a human in Santiago or California, life is juuuust right.


This reminds me a lot of the works of David Macaulay, the art style and writing style are very similar. He wrote some great books, amazing for curious kids.


This was a great post. Very easy to digest and lots of stuff to ponder on as my head slowly wraps itself around a few counter intuitive learnings.


The volume/surface area problem is the same reason why you generally don't see massive single celled creatures. Also, it's why smaller people can be pound-for-pound stronger than heavier people (muscle strength scales with regards to muscle cross section, whereas muscle needs to fill out the whole volume).


Leverages also have a lot to do with greater apparent strength in shorter athletes, though that varies by lift.

For bench press, short arms are an advantage, as well as where specifically the muscle anchors in the limb. Similarly for squats.

For deadlifts, the situation's slightly different: long arms help in that the bar needs to be moved a shorter distance, though femur length still benefits by being short. There's also femur-shin ratio, and how that plays with angles.

But yes, volume vs. cross section matters a lot.


This is explains a lot about the stature of elite marathoners: less volume per square area.


and on the same note of volume/surface ratio - Sun produces heat with the intensity (J/kg) of a pile of regular compost.


The quote that struck me (via Wikipedia): roughly an amphibian metabolic rate. 1/2 to 1/5 that of a mammal's.


Interestingly according to this some of the species farthest from the line of best fit (in both directions) are bats.

Pteropus Giganteus (Indian Flying Fox) appears to have an extraordinatorily slow metabolic rate per kg, scoring 0.044, yet Rousettus Aegyptiacus (Egyptian Fruit Bat) scores 5.508.


The scrolling seems perfectly normal to me, but that huge fixed banner that takes up 1/3 of the screen is just ridiculous.


That goes away (or is minimised) with JS enabled. Though there's still a small fixed header. I've nuked that with Stylish (CSS management extension).


I've removed it using uBlock Origin & live happily ever after :D


Huh. I wonder how this works for warm-blooded vs. cold-blooded animals?


Cold-blooded animals have to get rid of excess heat, too.


elephants scale after all


really hard to read this because the scrolling is acting all weird on firefox


scrolling is normal on safari. On the other hand, the unnecessary animations gave me a headache and I had to stop reading halfway through.


the scrolling works fine for me in Firefox 40.0.3 ... might be the extensions that I use that fixed it... NoScript, Adblock Plus or Privacy Badger


Can we start getting a label/tag for sites that hijack scrolling? The way we label pdfs and articles from previous years?


Hi there. Sorry about this, I didn't realize it was 'hijacking scrolling'. I tried a possible fix. Could you let me know if you still see the problem? Thanks.


Generally, do not hijack user experiences.

Scrolling, highlight/selection colour, fixed-position elements (I've ended up nuking your site's header entirely), autoplay audio/video, mouse action, click actions (either opening left-click in new tab, or center click in same tab), etc.

All violate the principle of least surprise/astonishment. Quite annoying.


> highlight/selection colour

You can have your horrible purple/blue... I'll take people hijacking those abominations any day of the week.

Otherwise, that's a good list. :)


If you don't like the defaults you can change it to what you want with a local default stylesheet. The issue isn't that the default is sane but that changes from default are jarring.

White text on a blue field works well for me.


The scroll on this site is unusable - it kept scrolling too far or not enough. The performance is awful too (low framerate on an i7-4790K + NVidia 980 Ti, which should be able to handle some simple scrolling)


Hi there - I'm a co-author of the post and put the site together. I'm sorry to hear that the scroll is acting up. I'd like to fix that. Can you (or anyone else seeing this issue) tell me if you see the same behavior on the other posts on the blog or just this one? Thanks.

EDIT: I disabled the 'smooth scrolling' option in my wordpress theme settings to try to fix this. Please let me know if that worked or if you're still seeing the issue. Thanks.


I had the terrible scroll when I first loaded the page 1-2 hours ago but can't reproduce it now on any of your posts including this one. Chrome 45.0.2454.85 64-bit linux.


Almost unusable once the jumping can of beans was in view. On Firefox latest stable, windows 8.1. Scrolling was happening in bursts and the entire browser UI was frozen. Once I managed to scroll past it, it worked fine.


ok, I think I see the problem. I swapped out that cocktail shaker animation with an animated gif of the same. Hopefully it should work smoothly now. Thanks for your help!


It's definitely much better now, and I'm on a lower spec machine this morning


btw... whatever plugin that was, it was also disabling page up/page down from working


Literally unusable in the case of MS Edge on a tablet - it appears to completely ignore touch input.


It also sent the cpu usage for chrome on my macbook skyrocketing from 5% to 106%. Pretty impressive. I ended up reading it in readability instead.[0]

[0]: https://www.readability.com/articles/v5jqgcjf


That link just redirects to the article.


Oh whoops you're right. Looks like it needs the extension installed.


OT: Why do sites insist on hijacking scroll behavior? It annoys me to no end


The desktop experience of this site is pretty terrible. I have smooth scrolling off because I don't like the lag. The scroll wheel on my mouse won't work consistently when the mouse is over certain elements on the page. The scroll bar is only a few pixels wide, so hard to use.


I use Firefoxes reading mode.


teste


test




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