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Comment by alan_cx | Hacker News Reader

I wonder how its prevents wear? Could be something quite revolutionary there for the finding. Some sort of new organic lubricant, or something in the gears that self lubricates.

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Maybe it doesn't. The last paragraph of the article implies that wear eventually would compromise the gears, but that the insect molting and replacing the old gears with new ones (frequently?) prevents it from being a problem.

Which leads to the classic answer to the age old question of how you make a car last forever: buy three, one to keep, and the other two for parts.

That's for very small values of 'forever', after 3x the average lifespan of some critical component you are again without transportation.

maybe self-healing? I am curious to know more

The creature sheds it exoskeleton at it grows. Adults don't have this gear "feature" apparently.

>Even stranger is that the issus doesn't keep these gears throughout its life cycle. As the adolescent insect grows, it molts half a dozen times, upgrading its exoskeleton (gears included) for larger and larger versions. But after its final molt into adulthood—poof, the gears are gone. The adult syncs its legs by friction like all the other planthoppers.

>Their idea: If one of the gear teeth were to slip and break in an adult, its jumping ability would be hindered forever. With no more molts, it would have no chance to grow more gears.

While I can't be certain, I believe it might not handle wear very well based on the article.

Near the end they mention that it molts several times growing new, larger versions of the gears. When its an adult, it actually loses these gears entirely.

Their theory is that when the insect is fully grown is gets rid of the gears since it can no longer molt and thus replace them if they become damaged.

What's interesting is that their replacement - essentially friction pads, IS expected to last the remainder of their life (and for other similar insects). I would have expected gears to last longer than something relying on friction, especially at those levels of energy.

Friction pads would probably have much more predictable wear (potentially in excess of the expected lifespan of the critter), whereas the discrete, stress-concentrating nature of gears would put them at higher risk of a single weak spot leading to cascading failure (then again, they'll still technically last almost a lifetime :)).

I guess that the difference is the failure mode for friction pads is more gracious than for gears, making survival more likely.

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