Draglines: control after takeoff
Distinguish observed jump stabilization from the lab's vertical fall analogy, then test the response after a line becomes taut.
Jump to a chapter
Original WebTug explanation with animated teaching diagrams and credited still photographs. On-screen text carries the lesson; there is no audio narration.
Diagrams simplify the science. Animation timing and diagram dimensions are illustrative, not measurements of live spiders.
Compare dragline settling →Read the full transcript
- A jumper with a silk connection
This still photograph introduces Hasarius adansoni. Before jumping, this spider attaches a dragline to its takeoff surface.
- Silk helps control body orientation
High-speed recordings showed draglines helping these spiders adjust body pitch in midair. The connection contributes to stable landing.
- A pull can change motion
Tension acts along the silk toward its anchor. Depending on its direction, that force can influence both movement and body rotation.
- Now isolate a vertical fall
In our lab analogy, gravity drives the fall. The safety line begins pulling only after it becomes taut and stretches.
- A simplification with a clear boundary
One spring and damper represent the loaded line. This vertical fall model does not reproduce a living spider's controlled jump.
- Which line settles with less bouncing?
Keep fall distance and stiffness fixed. Change energy loss, replay both settings, and compare repeated motion after the line becomes taut.
Scientific sources and media credits
Hasarius adansoni — Hasarius adansoni São Paulo.JPG by Leonardo Ré-Jorge, CC BY-SA 4.0. Photograph fitted within the video without changing its composition; labels and animated diagrams added around it.
Script, diagrams, animation, and editing: WebTug, September 27, 2026. This video adaptation is available under CC BY-SA 4.0; individual photographs retain their credited licenses.
What the game helps you notice
Experiments with Hasarius adansoni show dragline silk helping control body orientation and dissipate energy during a jump. In this challenge, the aiming arrow chooses the takeoff direction and speed. A higher branch requires enough upward motion; a lower branch gives gravity more time to act. Holding the silk brake reduces forward speed and body rotation.
Does the dragline power the jump?
No. Takeoff supplies the motion; the dragline can redirect or dissipate it. Brake too early and you may not reach the branch.
Pulling back is an aiming control, not how a real spider powers its jump. Real takeoff is leg-powered. The dotted guide assumes no braking; actual silk forces, air drag, and three-dimensional body motion are simplified here.
Try this experiment: What happens after the safety line becomes taut?
Keep fall distance and line stiffness unchanged. Predict which energy-loss setting produces less repeated motion after the line loads.
Open this experiment and compare A / B →Meet Hasarius adansoni and explore its research, then use the return link to play again. The challenge scores are game feedback, not measurements of your scientific understanding.
Primary research: Chen et al., Journal of the Royal Society Interface (2013)