From a standing start, humans can jump around 1.5 times their own body length. But this pales in comparison to the abilities of the regal jumping spider.
Otherwise known as Phidippus regius, the tiny arachnid is capable of jumping six times its own body length without so much as a run-up.
For a new study published in the journal Scientific Reports, researchers from the University of Manchester, successfully trained one member of the species—nicknamed Kim—to jump through a series of obstacles.
The aim of the research was to understand how the anatomy of jumping spiders—of which there are thousands of species worldwide—evolved and how they use their abilities in different situations. Furthermore, the results could have implications for the development of a new class of agile, jumping micro-robots.
"The force on the legs at take-off can be up to 5 times the weight of the spider—this is amazing and if we can understand these biomechanics we can apply them to other areas of research," Mostafa Nabawy, lead author of the study, said in a statement.
The team trained Kim—a female specimen weighing 150 grams and measuring 15 millimeters in length—to jump between various platforms separated by different heights and distances, recording her movements using advanced 3-D CT scanning techniques and high-speed, high resolution cameras.
After analyzing the data, the team came to the conclusion that this species makes use of different jumping strategies depending on the distance or height that needs to be overcome.
To cross shorter distances, Kim, tended to take a faster, lower-angled trajectory, which uses up more energy but reduces flight time, making the jump more accurate and, therefore, more effective for capturing prey.
However, when Kim was faced with a longer distance or a jump onto an elevated platform, she opted to use a more efficient method which used less energy. This technique would be more useful for traversing rough terrain, for example.
While the study has provided new insights into the spider's jumping abilities, some questions remain unanswered. Phidippus regius jumps by using internal hydraulic pressure to rapidly extend its legs. However, scientists are still unsure over whether this pressure enhances or replaces force from the muscles.
"Our results suggest that whilst Kim can move her legs hydraulically, she does not need the additional power from hydraulics to achieve her extraordinary jumping performance," Bill Crowther, a co-author of the study, said in the statement. "Thus, the role of hydraulic movement in spiders remains an open question."
