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How grasshopper jump???
A good jump means that the legs must push against the ground with high force, and high speed.
To be precise, a typical grasshopper weighing 2-3 gm will thrust against the ground with a force which peaks at about 30 gms when the legs are half extended, to give it a final take-off velocity of about 3 m.s-1.
Note how in the good jump there is a slight delay between the initial crouch and the actual jump.
The ultimate source of this push comes from the contraction of the muscles inside the leg.
To get a good jump requires two things.
First, the legs have to thrust on the ground with a lot of force.
If the thrust is too low, the animal doesn't get a fast enough take-off and it doesn't jump very far.
Second, the legs have to develop this force quickly.
If the thrust builds up too slowly, the legs will extend before the thrust reaches its maximum. Once the grasshopper is standing on tip-toe, it can't thrust against the ground any more.
Singing
A more attractive feature of some grasshoppers is their ability to sing. It's the males that
sing, and they do it to attract female mates, or to warn off other males. There are two different mechanisms for singing. In one (used by short-horned grasshoppers), there is a comb-like structure with a row of teeth on the inside of the hind leg, which gets rubbed against a ridge on the wing (a bit like running a stick along a fence very quickly). This produces a "chirp" sound.
In the other mechanism (used by crickets and long-horned grashoppers) there is again a
comb-and-ridge mechanism, but the structures are on the left and right forewings, which rub over each other.
Short horned grasshoppers have ears in the sides of the abdomen. Long-horned grasshoppers and crickets have ears in the knee-joints of their front legs.
Amazing fact. The extensor muscle from the back leg of an adult female locust (Schistocerca
gregaria) can develop a force of up to 1.4 kg. This means that the muscle from one back leg of a grasshopper (admitedly quite a large one) can lift almost a bag-and-a-half of supermarket sugar!
Grasshopper
How grasshopper jump???
A good jump means that the legs must push against the ground with high force, and high speed.
To be precise, a typical grasshopper weighing 2-3 gm will thrust against the ground with a force which peaks at about 30 gms when the legs are half extended, to give it a final take-off velocity of about 3 m.s-1.
Note how in the good jump there is a slight delay between the initial crouch and the actual jump.
The ultimate source of this push comes from the contraction of the muscles inside the leg.
To get a good jump requires two things.
First, the legs have to thrust on the ground with a lot of force.
If the thrust is too low, the animal doesn't get a fast enough take-off and it doesn't jump very far.
Second, the legs have to develop this force quickly.
If the thrust builds up too slowly, the legs will extend before the thrust reaches its maximum. Once the grasshopper is standing on tip-toe, it can't thrust against the ground any more.
Singing
A more attractive feature of some grasshoppers is their ability to sing. It's the males that
sing, and they do it to attract female mates, or to warn off other males. There are two different mechanisms for singing. In one (used by short-horned grasshoppers), there is a comb-like structure with a row of teeth on the inside of the hind leg, which gets rubbed against a ridge on the wing (a bit like running a stick along a fence very quickly). This produces a "chirp" sound.
In the other mechanism (used by crickets and long-horned grashoppers) there is again a
comb-and-ridge mechanism, but the structures are on the left and right forewings, which rub over each other.
Short horned grasshoppers have ears in the sides of the abdomen. Long-horned grasshoppers and crickets have ears in the knee-joints of their front legs.
Amazing fact. The extensor muscle from the back leg of an adult female locust (Schistocerca
gregaria) can develop a force of up to 1.4 kg. This means that the muscle from one back leg of a grasshopper (admitedly quite a large one) can lift almost a bag-and-a-half of supermarket sugar!
Grasshopper
