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imbluedabedeedabedaa t1_j5qdycm wrote

Reply to comment by colcob in If I had two cups of water, one normal size and one as big as a swimming pool and stirred them both with proportionally sized spoons, would the larger pool of water keep spiraling longer than the smaller? by r3volc

Otherwise known as the square-cube law!

Another great (but completely unrelated) example of this law explains the design differences between large and small animals. As a creature gets larger, its mass increases at a cubic rate (volume, m^3) but muscle/bone strength is proportional to their cross sectional area (m^2). This is why an elephant has such massive muscles/bones when (proportionally) compared to a dog.

It also impacts body temperature--since heat generation is proportional to body volume, but the ability to reject heat is proportional to the skin area. This explains the elephants' massive ears, and also why most cold blooded animals are very small.

If you scaled a dog up to elephant size it would collapse under its own weight before dying of heat. If you scaled an elephant down to dog size it would probably freeze to death. All because of math!

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silvercup011 t1_j5r3fa1 wrote

How do baby elephants not freeze to death? They are the size of a dog…

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cobywaan t1_j5remzo wrote

Baby elephants are like 250-300 lbs when born, that is much larger than all but the most massive outliers of the biggest breeds of dogs

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crackaryah t1_j5r4hxl wrote

It wouldn't freeze. Endotherms regulate their body temperatures by modulating their metabolisms. Not to mention that modern elephants don't live in cold places. Ancient elephants (mammoths) were highly insulated. Metabolism can be modulated a lot. There are small "warm blooded" animals that have a body temperature above 37 C in the summer, but hibernate during the winter, dropping their body temperatures to below 0 C. They don't freeze and they certainly don't die. There is even some evidence that hibernation contributes to longevity.

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blind_ninja_guy t1_j675xlf wrote

Good to know that the dog sized elephants that you could hold in whatever that moovie was where they go find atlantus before it again falls into the see is not realistic.

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