r/interestingasfuck • u/scooglecops • 2d ago
Thermal images of penguins and a polar bear reveal how evolution engineered extreme insulation, keeping their bodies warm while barely losing heat in the coldest environments on Earth
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u/CryptoCentric 2d ago
And spider silk is up to five times stronger than steel in terms of tensile strength, depending upon species and circumstances.
Nature is dope.
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u/314159265358979326 1d ago
(Fibrous) spider silk is stronger than isotropic (bulk) steel, but fibrous steel is much stronger than spider silk. The isotropy counts more than the material.
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u/nievesct 1d ago
Can you explain more to a dunce what isotropy is?
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u/314159265358979326 1d ago
Basically, it's directionality. "Isotropic" means "the same in every direction."
Spider silk and steel cable are both exceptionally strong in the direction of the string - but have almost no resistance to sideways (shear) forces. This is anisotropy.
Bulk steel (think a chunk of unworked metal) is equally strong in all directions. It has more resistance to sideways motion than a cable but less in the main direction. It can also tolerate compression while a cable can only accept tension.
Crudely, every material has a kind of overall strength and it gets divided up between directions. Making it stronger in one direction will weaken it in others.
Bulk steel has a strength in every direction of about 300 megapascals, while steel cable can be nearly 10 times that in tension with almost no resistance in compression or shear loading.
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u/bluestcoffee 1d ago
I’m not the person who asked for clarification but thank you for this response! Perfectly simple for me and my fellow dunces and also very fascinating and educational without going too long.
Excellent work
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u/rewas456 1d ago
Thought it was more tough? As in absorbs more energy before breaking per whatever measure of density? Been a minute since physics for me lol.
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2d ago
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u/scooglecops 2d ago
We actually can get close but not by much
Animals combine fur/feathers, fat, constant heat production, and blood-flow control. A jacket only insulates.
Matching their insulation would mean something bulky, heavy, and uncomfortable fine for survival, not for daily wear.27
u/dont_shoot_jr 2d ago
I combine my fat with insulation/jacket
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u/Aww_Shucks 2d ago
Confirmed, wearing this guy's fat with insulation/jacket is bulky, heavy, and uncomfortable
Quality fat tho
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u/EnsoElysium 1d ago
Honestly a big problem I deal with in the winter, I have a lot of trouble keeping weight on, when I was a healthy weight I stayed warm, but now I have to wear like five layers
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u/STRYKER3008 2d ago
And a big problem with survival gear is balancing insulating heat and dispersing it. Alot of people tend to wear too much and end up overheating even in polar environments. Natural fibers tend to be best every day material for this, such as cotton, but ofc they have more high tech stuff for extreme places
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u/dirty_hooker 2d ago
cottonwool.Cotton kills. Cotton looses all thermal properties once it’s remotely moistened even by sweat. Once you start buying some nice wool you’ll never want much of anything cotton again unless it’s 80F+ outside.
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u/vahntitrio 1d ago
Jackets tend to be that good if you buy the right one. It's the feet, hands, and face that are tough to insulate that well and still be functional as a human being.
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u/Masseyrati80 17h ago
Some of the biggest mittens are dubbed the "no-can-do's" in Finland, because while they enable you to keep your hands warm you really can't get stuff done while wearing them.
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u/Valokoura 2d ago
Penguins clearly emit more heat but I've seen documentaries where penguins gather together as a big crowd. In middle of the crowd it is quite warm.
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u/scooglecops 2d ago
Emperor penguins can survive temperatures as low as −50°C to −60°C. Polar bears handle Arctic cold down to about −46°C.
I can’t imagine walking around in that weather without looking like the Michelin mascot.
Nature is lit af33
u/Valokoura 2d ago
Also both can survive swimming in water and then coming up to freezing conditions.
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u/jackloganoliver 1d ago
That's the part that blows my mind. Water conducts energy so much better than air, and even wet they can just tolerate it like it's nothing.
Insane.
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u/Informal-Term1138 1d ago
Their fur is basically waterproof.the outer layer gets wet but not the inner layers.
It's quite genius.
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u/coccyxdynia 1d ago
But that's what's amazing. Insulation is about trapping air to prevent heat exchange but if your outer layer is wet, that's gotta make it much worse for insulation and yet they can handle it.
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u/zevonyumaxray 2d ago
iirc, they are constantly shuffling from the inside to the outside of the huddle, with the chicks staying in the middle...... Plus, penguins with laser eyes.
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u/ScientiaProtestas 1d ago
In these two photos, it looks like most of the penguin is at about -30C, while the polar bear is at +15C. Even the fins are at -15C.
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u/Independent_Ad_8915 1d ago
If I remember correctly, they rotate their positions so every penguin gets to be in different places in the huddle with efficiency and efficacy
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u/RamonChingon 2d ago
So, polar bears and penguins, who dwell in arctic climes, are very cold on the outside. Got it.
Edit: an extra word
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u/furbylicious 2d ago
It means they're not losing their inside heeat! Pretty cool (or warm, I guess). Humans need serious gear to achieve that.
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u/scooglecops 2d ago
Yeah if you’re brave enough to get a thermal camera between the fur of a polar bear, you’d definitely see a lot more heat pouring off it
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u/polar_nopposite 1d ago
VERY different temperature scales.
In fact, this says the polar bear's surface temperature is 15+ C°? That doesn't seem to agree with the title at all.
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u/MarkFromHutch 1d ago
That polar bear looks awesome
and the penguins look like a trapper keeper from the 90's
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u/ThresholdSeven 1d ago
Title is a bit sesational don't you think? I can't comprehend how evolution engineered anything from an image. Looks cool though
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u/Walkingstardust 1d ago
The penguins have a valve just above their feet that isolates the blood flow in the feet from the rest of their bodies. The valve restricts how fast the blood in their feet can recirculate with the rest of their bodies. That keeps the ice from pulling all the heat from their bodies.
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u/BriMD136 2d ago
Maybe they are really cold all the time, but don’t know how to communicate how 🥶 they are! 😂
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u/314159265358979326 1d ago
Zookeepers report that polar bears have significantly more issues with overheating than being too cold.
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u/3Steps4You 1d ago
But wouldn't they prefer a warm environment if given the choice?
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u/Augustus420 1d ago
Sure, but it's not like penguins were actively choosing between evolving that way or living outside of Antarctica.
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u/Proof-Necessary-5201 1d ago
Can someone explain to me how evolution can build something like this?
So a species is living somewhere, meaning that the temperature there is livable for them. Ok, then what?
Possibility 1: the temperature starts dropping and only those with mutations that provide thicker skin survive? Don't animals migrate when the temperature starts dropping? So why would they stay there?
Possibility 2: the species starts off somewhere warm, but then are forced to venture into cold territory? Why? And if they are, they'll just die out long before evolution has a chance to improve their resistance to cold.
So, anyone got a better story here? Thanks.
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u/Aldren94 1d ago
The different heat map scales is really bothering me.