Owusu MensahProfessor RiceBio LabOctober 5, 2010

JUMP PERFORMANCE BETWEEN GRASSHOPPERS AND HUMANS

Introduction: Most people believe that humans could definitely out-jump

grasshoppers. However is this statement true? By just looking at the physical properties one will

say that humans are relatively stronger, bigger and faster but that is not the case. A comparison

between the jump distance and body length ratios of both humans and grasshoppers was

constructed and it supported the hypothesis that grasshoppers jump 26 times quicker than

humans. A comparison between the leg length and body length ratios better supported this

hypothesis, which explains how grasshoppers’ legs allows them to better launch its mass,

because the body part responsible for propelling its mass is relatively greater than in humans.

However, when the mass of femur muscle was compared to the body mass ratios it did not

support the hypothesis. Therefore, a video analysis has been constructed to determine the

jumping velocity (acceleration) between humans and grasshoppers.

Hypothesis

Grasshoppers will accelerate faster than humans therefore reaching a higher distance

compared to humans due to the maximum forces generated during of the jump.

Experimental Procedure

Measured force production using video analysis. Humans had white duck tape at the

waist level to visualize the starting point. The videos of both humans and grasshoppers were

edited to have two segments: the beginning of the jump and the beginning of the meter stick

sequence. They were then exported into “Quicktime” to closely find details. Time is measured by

click on the white paint or duck tape once, move to the adjacent frame and double click to finish

measuring. Calculate velocity by dividing the distances of the frames by the times between

images, which was calculated by the Professor. Since grasshoppers jump so quickly that it is had

to attain the details, an average of the takeoff time is given by the Professor to be used. Divide

the velocity by the takeoff time to get acceleration. For humans, details were captured therefore,

count the frames from when the heels are just raising off the ground until full extension of feet

off the ground. Calculate acceleration, multiply the numbers of frames by the time between two

consecutive video frames to determine takeoff then divide velocity by takeoff time. To determine

the force produced during the jump, acceleration is multiplied by the body mass (from last

week). Lastly calculate the muscle-specific force that is dividing Femur Muscle Mass (Kg) by

the jumping force (N). A t.test is done to find out how significantly different the two species are.

Results

The average of Acceleration(m/sec) of the grasshoppers was significantly high(106)

compared to humans(13). The average of grasshoppers and humans in muscle-specific force

[jumping force(N) over femur muscle mass(kg)] were 882 and 62 while the standard deviation

were 288 and 39 respectably. Without hesitation grasshoppers averages and standard deviation

outnumbers that of humans.

Figure 1. This graph above shows the average and the standard deviation of grasshoppers and humans. Humans bar is on the left side labeled 1 and the grasshoppers right labeled 2.

Discussion

From the graph above, the differences of the forces(N/kg) generated by both grasshoppers and

humans are vividly showed.(series1). The difference in average of humans to grasshoppers in the

muscle-specific force [jumping force(N) over femur muscle mass(kg)] which is about 820.5

likewise the standard deviation which is about 248.83 From the results is it observed that the

average and the standard deviation difference of grasshoppers compared to humans is relatively

significant. However is data above is enabled by the acceleration(m/sec) of humans and

grasshoppers which is also relatively big (93.25m/sec). From the video analysis performed to

determine the differences in jumping performance between grasshoppers and humans, it is

observed that grasshoppers relative jump greater than humans. The video data support my

hypothesis such that it gives a significant difference on the acceleration generated by

grasshoppers when jumping compared to humans. All the species of grasshoppers observed

generated a bigger muscle-specific force in N/Kg than humans. There the results presented

implies that grasshoppers accelerate quicker than humans therefore, achieving a larger distance

performance relative to humans.