Can an ant die from falling and hitting the ground?

Related: what is the heaviest animal that can survive an impact at terminal velocity?

no.
citewith calculations.

As for the mass of a creature that will die as you scale up–I am not physicist (I don’t even own a white lab coat), but I would think there’s mitigating factors to consider.
Mass is one, surface area is another. Ant have sticky-outy parts that create drag and displace force (unlike, say, a grub). Surface tension of their exoskeleton creates another variable.

So my arm-chair sciencin’ come up with the variables of mass, shape, and composition.

Think of a soap bubble. Extremely low mass, extreme fragilitiy. Think of something with the same weight of a bubble falling at the same velocity, like a human hair. It won’t explode as a bubble will.

I think the variables make the question of “how big of a bug will die from impact” kind of impossible to answer.

Then again, I’m an artist. Not a sciencologist. :slight_smile:

ESB=Empire State Building.

From what I’ve read, mice that strike at terminal velocity tend to be stunned, but typically not seriously injured; so a bit larger than that I’d guess for an uncontrolled fall. Cats are much larger, but when falling they instinctively take up a parachutist-style maximum drag posture that lowers their terminal velocity (and helps create the “cats always land on their feet” myth); to a degree they are actually better off falling from greater heights, since it gives them time to get into position. Unlike mice though they are likely to suffer serious injury from large falls.

There’s a quotation from the essay “On Being the Right Size” by J. B. S. Haldane:

> You can drop a mouse down a thousand-yard mine shaft; and, on arriving at
> the bottom, it gets a slight shock and walks away, provided that the ground is
> fairly soft. A rat is killed, a man is broken, a horse splashes.

http://irl.cs.ucla.edu/papers/right-size.html

So somewhere between the size of a mouse and a rat is the dividing line where an animal is killed, if Haldane is correct. Der Trihs says that a cat would survive, so perhaps the dividing line is a little heavier in weight than a rat.

Experimentation has apparently shown that cats are most likely to die if dropped from the 7th floor of a building. Lower down and the fall is not high enough and at higher altitudes the cats are able to position in a parachute position… High-rise syndrome - Wikipedia

From the link, it looks like this was empirical evidence gathered from what hopefully were accidents. I was wondering what sort of graduate from Evil University signs up for these sorts of experiments! :slight_smile:

Thank you for posting that. The rest of my day was going to have a dark cloud if I hadn’t read that.

Being a bit pedantic here, but a confusion crops up in almost every discussion where “terminal velocity” is used. I’m hoping to head off the confusion …

There is no single universal “terminal velocity” for things falling in Earth’s gravity in Earth’s atmosphere. The terminal velocity of a cat, a rat, a man falling head first, and a man falling spread eagled are all different. The terminal velocity of a 1lb bag of feathers is different from the terminal velocity of a 1lb bag of lead shot.

Thank you.

I love Haldane. That is all.

One should also mention that extremely lucky humans have been known to occasionally survive impacts at terminal velocity, so any absolute hard limit to survivability must be somewhere larger than human-sized.

Implicit in the OP’s question is impact with what?

Impacting a horizontal concrete or granite surface is different from impacting really wet mud is different from impacting deep water is different from obliquely impacting an almost vertical cliff face covered in 30 feet of powdery snow.

I think all the humans who’ve survived terminal velocity impacts did it by hitting something pretty soft at a pretty oblique angle. e.g. sliding down multiple layers of snow-covered pine boughs & eventually landing in a steep & deep snow bank.

Conversely, the maximum animal size to survive terminal velocity impact on a very narrow very sharp spike is much smaller, probably squirrel-sized. Man, *those *experiments would really piss off the PETA folks.

That’s a funny coincidence - I used this quote in another online discussion just a few minutes ago…

I remember hearing that large spiders, i.e. the scale of tarantulas, can die from a fall of even a few metres, such as from a ceiling. Not sure if that’s an exaggeration.

LSLGuy: I think it makes little sense to ask the question without assuming a really hard, flat surface, like concrete. I realize if we’re talking about dropping large animals like elephants then there’s going to be a difference between concrete and steel, as well as the thickness of it. But once we get to animals of a size where that would make a difference, I think we can assume they’re well past the size threshold where we know they would die from the fall.

Unless I’m mistaken, ants don’t have enough mass to be fatally injured from a fall. It’s just like how water-spiders are able to move along the surface of a pond without drowning.

Terminal velocity is relative to the subject’s mass, is it not?

You stole my post! :frowning:

I can’t remember anything I’ve read about the care and feeding of large spiders, most commonly tarantulas, that didn’t include a warning about that in the section about handling them.

First link on the Googles,

CMC fnord!

I agree that the OP probably meant impacting onto a flat more-or-less unyielding surface. And I agree that it makes sense from a problem-solving perspective to assume some plausible, typical, & uniform conditions.

I was responding to Chronos’ post which pointed out that some humans have survived in very special circumstances. I pointed out the opposite very special circumstances (falling on a sharp spike) precisely to illustrate the folly of heading down the rabbit trail of differing landing surfaces.

I guess I should have been a little more explicit.

It depends on the subject’s mass, cross-sectional area, and to a lesser extent, shape. Low mass and high area lead to a lower terminal velocity. An elephant does have a considerably larger cross-sectional area than an ant, which looked at in isolation would imply a lower terminal velocity, but of course an elephant also has much more mass. For living things which all have approximately the same density and roughly the same shape (assume a spherical cow), mass goes up as the cube of linear measurement while cross-sectional area goes up as only the square, so in general, big animals will have a faster terminal velocity than small animals.

I’m not going to argue with what has been posted so far, but there are anomalies that can confuse the observer if he isn’t careful.

There are accounts of cats and dogs surviving falls from several stories. However, we shouldn’t take them as normal. Nobody takes a fatally injured dog or cat to the vet, so they don’t get recorded.

People rarely survive suicidal leaps from high bridges into water. However, the Acapulco cliff divers survive their long dives. Water is odd stuff. You can dive into it and swim in it, but when you speed up your impact it seems more like a solid. You’re more likely to be hurt while water skiing than snow skiing.

You might have seen a daredevil carnival diver dive from an astounding height into a little pool on the ground. Some time back, General Motors studied one of these stunt divers as sort of a living crash test dummy. The diver’s technique was to arch his back as he approached impact, so that his chest struck first. GM rigged him up with accelerometers on several parts of his body.

GM put an article about it in their company-wide newsletter, along with a pic of the guy inches above the water. Unfortunately, I have told you all the info I have on that study.