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Im writing a story about a less evolved world where a giant ant colony takes in a stranded stranger. In a world where ants are the size of a small tarantula, how many ants would it take to lift/transport a full grown (human) adult? Also, how big would a single ant have to be to lift a (human) adult above its head?
Jesse Schoell
Posted 2017-03-27T16:25:45.427
Reputation: 29
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Depending on your internet source: first, second, third
Ants can lift anywhere between 50 to 5,000 times their own body weight, but also ants are on a different scale, so if we take a conservative 5 times their own weight, given that a dog sized ant would be crushed under the weight of its own exoskeleton.
From there we need the average weight of a human, which google tells me for a man is 83.6kg, and for a woman is 70.2kg (convert this if you want, but they are the units I know and understand)
Now we need the weight of a tarantula, which is 28 - 83 grams, a huge range admittedly, but on the assumption that you're using an average "adult" tarantula, lets assume they weight 70g. which means you're looking at a minimum of 201 of these just to carry your woman, or 239 for a man.
However we need to consider whether that is possible, a tarantula is typically 12cm long, assuming its that wide, then every tarantula takes up 144cm^2, now an average human male is 178cm, and 43 cm wide (shoulder width), so if you're lying down you can potentially have 53 tarantulae carrying you, as no more could fit, but given my estimate of 5 times body mass, these tarantulae would have to take about 20 times their body weight, assuming your human is average, which means they would get crushed to death and probably kill the human.
Luckily for your stranded human, there is the art of handwavium, so you can ignore the specifics of the science, and take your number of tarantula to be about 50 - 200 depending on whether you want to match surface area or the amount of weight lifted
Alex Robinson
Posted 2017-03-27T16:25:45.427
Reputation: 1 064
I feel that this problem is so complex that it can only be solved empirically (and it, of course, can't), and you'd always be surprised by the actual result. But I would say completely matching the surface area would be the best bet. And I think you missed the initial number for tarantulae ("you can potentially have... tarantulae"), which should come out to about 53, if I'm not mistaken. – khantazm – 2017-03-27T16:52:01.220
@khantazm i calculated it then forgot to put it in, thanks for spotting it! also i tend to agree with what you say about empirically solving, but of course we cant, so we take real life examples and try to match the question - what i love about the hard science tag – Alex Robinson – 2017-03-27T16:58:00.503
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For the "single ant problem" this is a hint
– EngelOfChipolata – 2017-03-27T16:43:35.5701Oh. I thought you meant an adult ant.. You meant an adult human, I guess! – Konchog – 2017-03-27T16:53:38.437
1Reminder to close-voters: The problem cannot be fixed if the OP is not made aware of it. – Frostfyre – 2017-03-27T16:58:14.120
1The real problem here is the cube-square law and its variants. Strength doesn't scale with size, nor are exoskeletal creatures much larger than tarantulas (say 6 in/15 cm) even workable without fundamental changes to their body design. – jamesqf – 2017-03-27T18:47:28.237
@jamesqf the "single ant" solution i think is a bust, but if you're having multiple tarANTula, then it still can't work, but it nearly can – Alex Robinson – 2017-03-27T19:00:48.790
I am thinking this needs to be closed and referenced to the square cube law question. – James – 2017-03-27T19:14:12.587
Possible duplicate of Can you simply scale up animals?
– James – 2017-03-27T19:15:36.843You would need an infinite number of giant ants, since giant ants would fail because of square-cube problems. A large but finite number of normal sized ants would have the strength needed, but it would take some type of ant powered machinery to apply that strength to lifting and carrying the human. – M. A. Golding – 2017-03-29T04:50:35.633