How This Uncrushable Beetle Can Survive Being Run Over By a Car (gizmodo.com) 46
fahrbot-bot shares a report from Gizmodo: The diabolical ironclad beetle, in addition to having one of the coolest names in the animal kingdom, boasts one of the toughest natural exoskeletons. A team of scientists has finally figured out the secret behind this extra durable armor and how these insects can survive getting run over by a car.
As wise people often say, a reed that bends in the wind is stronger than a mighty tree that breaks during a storm. New research published today in Nature suggests the diabolical ironclad beetle (Phloeodes diabolicus) is an adherent of these sage words. Their exoskeletons are extra tough, but when the pressure literally gets to be too much, their protective shells take on an elastic quality that results in a kind of stretching rather than breaking. The scientists who made this discovery -- a team from Purdue University and the University of California-Irvine -- say the unique strategy employed by the diabolical ironclad beetle could inspire the creation of innovative materials, namely components capable of dissipating energy to prevent catastrophic breakage. According to the experiments, diabolical ironclad beetles can withstand an applied force of 150 newtons, which is 39,000 times its body weight. "If we were to compare this to humans (not a great example, given the vastly different scales involved, but fun nonetheless), that would require a 200-pound person to endure the crush of 7.8 million pounds," the report says.
"A tire passing overhead would inflict 100 newtons of force, which explains how these beetles can survive run-ins with cars. The researchers say other beetle species can't handle even half of this load."
As wise people often say, a reed that bends in the wind is stronger than a mighty tree that breaks during a storm. New research published today in Nature suggests the diabolical ironclad beetle (Phloeodes diabolicus) is an adherent of these sage words. Their exoskeletons are extra tough, but when the pressure literally gets to be too much, their protective shells take on an elastic quality that results in a kind of stretching rather than breaking. The scientists who made this discovery -- a team from Purdue University and the University of California-Irvine -- say the unique strategy employed by the diabolical ironclad beetle could inspire the creation of innovative materials, namely components capable of dissipating energy to prevent catastrophic breakage. According to the experiments, diabolical ironclad beetles can withstand an applied force of 150 newtons, which is 39,000 times its body weight. "If we were to compare this to humans (not a great example, given the vastly different scales involved, but fun nonetheless), that would require a 200-pound person to endure the crush of 7.8 million pounds," the report says.
"A tire passing overhead would inflict 100 newtons of force, which explains how these beetles can survive run-ins with cars. The researchers say other beetle species can't handle even half of this load."
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Something's funny with the numbers (Score:1)
g (acceleration due to gravity) is roughly 9.8m/s^2. A force of 150 Newtons is the same as the gravitational force on a mass of about 15.3kg. I don't know what most people drive, but my car's mass is a heck of a lot more than 15.3kg. Even if only one-quarter of the weight of the car is transmitted through each tire, that still doesn't add up. My car's mass is much more than 61.2kg. So what gives?
I mean, it's still impressive that the beetle could survive having a 15kg mass put on top of it. I don't
Re:Something's funny with the numbers (Score:5, Informative)
Re: Something's funny with the numbers (Score:2)
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Re:Something's funny with the numbers (Score:5, Informative)
You car's weight is distributed throughout its tire's contact patch. The contact patch of a tire is (roughly) equal to the weight the tire supports divided by the air pressure in the tires.
For example, the old Toyota Camry used in this experiment probably weighs about 4500 pounds, driver included, and probably has a tire pressure of 30 pounds/square inch. 4500 pounds / 30 psi = 150 square inches.
Now if you ran over a beetle with your tires inflate to 30 PSI, and the beetle's body area in contact with the tire were about 1 square inch, you'd end up with 30 pounds of force applied to the beetle. In this case the beetle is quite small, it'd fit in a rectangle about 20 mm long by about 5 mm wide -- an area of about 0.15 square inches as an upper bound.
30 psi * 0.15 square inches = 21 newtons.
Re: Something's funny with the numbers (Score:1)
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It does, although the model I used is somewhat idealized -- e.g. a zero PSI tire doesn't have infinite contact patch area. But over ranges of pressure where the contribution of the sidewall and other structural aspects of the tire are negligible it's a fair approximation.
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Say what? The inflation of the tires has everything to do with the size of the contact patch. 30 PSI means that there is an outward force of 30 lbs on every square inch of tire. The weight of the car on the road is applying an inward force on the tire. If the rim is not contacting the ground, air is holding it up. That means that the outward forces and inward forces must be the same. If the outward force is 30 PSI, the inward force must also be 30 PSI. If you have 900 lbs to hold up that is going to
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Upside-down car: if there are 0 lbs being held up, but the outward force is still 30PSI, do the tires explode?
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Oh brother. I can only assume you failed 9th grade physics. Every single one of your 'points' is incorrect.
First, pressure vs force. Pressure is merely force/area. It's right there in the name PSI - pounds (force) per square inch (area).
It should be obvious that if you have a movable membrane separating two areas of differing pressure, the membrane will move towards the area of lower pressure unless some force stops it. If the pressures are equal, the membrane does not move.
The force, in this case, is
Re: Something's funny with the numbers (Score:1)
Re: Something's funny with the numbers (Score:2)
Re: Something's funny with the numbers (Score:1)
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Re: Something's funny with the numbers (Score:1)
That means that the outward forces and inward forces must be the same.
this statement is exactly correct. However, psi is not a unit of force, it is a unit of pressure. The pressure does not follow this equality, and even so, the forces on the tire also involves the flexibility of the tire material. A tire made out of a latex balloon will have a much larger patch than one made out of 2" steel, at the same psi.
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Now if you ran over a beetle with your tires inflate to 30 PSI, and the beetle's body area in contact with the tire were about 1 square inch, you'd end up with 30 pounds of force applied to the beetle.
You fail to take into account elasticity of the tires at the contact point and the sidewall elasticity.
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Yes, it's a simplified model that doesn't work very well, say, at 0 PSI. But it's a reasonable approximation at 30 PSI.
And how is this an evolutionary advantage? (Score:2, Funny)
Did it evolve this capability in the past 100 years?
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Getting stepped on by a dinosaur.
Re:And how is this an evolutionary advantage? (Score:4, Informative)
I actually caught one of these for a high school class bug collection. Everything else I put a pin through and stuck into the styrofoam base. This guy though, I struggled with. I twisted the pin thinking I could eventually drill it through but no such luck. I gave up, and resorted to gluing it to the top of the pin instead. The teacher seemed to understand.
Re:And how is this an evolutionary advantage? (Score:5, Funny)
I actually caught one of these for a high school class bug collection.
Such a critter would be an awesome pet for a teenage boy:
Teacher: "Um, class . . . who has a house pet at home . . . ?"
Buffy: "I have a Golden Retriever named Muffin!"
PolygamousRanchKid: "I have a diabolical ironclad beetle named Beelzebub."
Re:And how is this an evolutionary advantage? (Score:5, Funny)
You almost nailed it...
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You almost nailed it...
I misread the name as beetlzebub.
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Beetle Zee Bug!
Re: And how is this an evolutionary advantage? (Score:3)
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My nephew is actually breeding beetles.
Mostly European specimen, though.
Perhaps I suggest such monsters to him ...
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good thing you used glue.
If you had succeeded with the pin, you would have let the betelgeuse out . . .
hawk
Synthesise It (Score:2)
Then make tanks out of it.
Better write up (Score:5, Informative)
Wikipedia says the beetle can live up to 8 years and is native to the west coast of North America.
Science News has a better write up. https://www.sciencenews.org/ar... [sciencenews.org]
Within the diabolical ironclad beetle’s own tanklike physique, two key microscopic features help it withstand crushing forces. The first is a series of connections between the top and bottom halves of the exoskeleton. “You can imagine the beetle’s exoskeleton almost like two halves of a clamshell sitting on top of each other,” Kisailus says. Ridges along the outer edges of the top and bottom latch together.
But those ridged connections have different shapes across the beetle’s body. Near the front of the beetle, around its vital organs, the ridges are highly interconnected — almost like zipper teeth. Those connections are stiff and resist bending under pressure.
The connective ridges near the back of the beetle, on the other hand, are not as intricately interlocked, allowing the top and bottom halves of the exoskeleton to slide past each other slightly. That flexibility helps the beetle absorb compression in a region of its body that is safer to squish.
The second key feature is a rigid joint, or suture, that runs the length of the beetle’s back and connects its left and right sides. A series of protrusions, called blades, fit together like jigsaw puzzle pieces to join the two sides. These blades contain layers of tissue glued together by proteins, and are highly damage-resistant. When the beetle is squashed, tiny cracks form in the protein glue between the layers of each blade. Those small, healable fractures allow the blades to absorb impacts without completely snapping, explains Jesus Rivera, an engineer at UC Irvine.
Frogs (Score:2, Offtopic)
When I was a kid one of the kids from my neighborhood ran over a frog on his bike. The guts of the frog burst out .. but we were amazed to see that maybe a minute later it sucked back in all its organs and hopped away like nothing happened.
Re:Frogs (Score:4, Funny)
Did they use VW's Beetle car? (Score:3)
:D
Diabolical? (Score:2)
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Your colleagues are already under its power. You will be next. And after it claims the last entomologist (hobby or pro), from there, it is an easy jump to ruling the world! (You really should hear the beetle's micro diabolical laugh... quite cute, really.)
What evolutionary pressure drove that I wonder? (Score:3)
Some things in nature "just happen", but complex engineering usually arises from specific environmental pressure. I wonder: what in the world was regularly subjecting these beetles to 150 newtons of pressure prior to automobiles?
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Some things in nature "just happen", but complex engineering usually arises from specific environmental pressure. I wonder: what in the world was regularly subjecting these beetles to 150 newtons of pressure prior to automobiles?
You have probably heard the joke about two friends running away from a bear--one points out that he doesn't need to outrun the bear, just his 'friend'... I think that the sharp, pointed teeth/beaks of many warm-blooded predators could still pierce this beetle's defenses given some effort. But if you consider that potential predators often have the opportunity to choose between trying to bite and digest this beetle vs one of his softer cousins, I expect many predators to learn to prefer the softer beetles v
Ever squash a tick? (Score:1)
Breaking shear force (Score:2)
If you happen to breaking hard as the tire passes over it, the shear force should easily rip such a beetle apart.