Skip to main content

The surprising reasons animals play dead - Tierney Thys

  • 2,191,003 Views
  • 8,643 Questions Answered
  • TEDEd Animation

Let’s Begin…

From lemurs to lizards, ants to amphibians, sharks to chickens, hundreds of animals "play dead" as a survival tactic. But how and why do animals do this? Tierney Thys explains how this curious behavior, known as tonic immobility or TI for short, can be used as a defense or offense.


Customize this lesson200

Create and share a new lesson based on this one.

About TED-Ed Animations

TED-Ed Animations feature the words and ideas of educators brought to life by professional animators. Are you an educator or animator interested in creating a TED-Ed Animation? Nominate yourself here »

Meet The Creators

  • Educator Tierney Thys
  • Director John R. Dilworth
  • Script Editor Emma Bryce
  • Animator John R. Dilworth
  • Compositor OG Marcontell
  • Sound Designer William Hohauser
  • Associate Producer Bethany Cutmore-Scott, Elizabeth Cox
  • Content Producer Gerta Xhelo
  • Editorial Producer Alex Rosenthal
  • Narrator Susan Zimmerman
  • Fact-Checker Francisco Diez
Additional Resources for you to Explore
For additional background and insight into this remarkable behavior, check out The Impossible Escape, written by Carlo Alfredo Clerici and Laura Veneroni.

Every class of vertebrate, as well as many arthropods, play dead—and each species has its own distinct way of doing it. From male spiders that feign death to avoid sexual cannibalism by their mate to the pygmy grasshoppers that stick out their spines to avoid being swallowed, Stephen M. Rogers and Stephen J. Simpson provide a terrific overview of this last-resort behavior, including how it works and its evolutionary significance.

To learn how to induce TI in sharks, cats, chickens and rabbits, check out Can You Hypnotize a Shark? There’s a dark side to this capability. In cases of sexual assault, when the aggressor induces immobility in the victim, this involuntary response can be misinterpreted in court as silent consent. For more on that, read this article from Scientific American.

Customize this lesson

Create and share a new lesson based on this one.

About TED-Ed Animations

TED-Ed Animations feature the words and ideas of educators brought to life by professional animators. Are you an educator or animator interested in creating a TED-Ed Animation? Nominate yourself here »

Meet The Creators

  • Educator Tierney Thys
  • Director John R. Dilworth
  • Script Editor Emma Bryce
  • Animator John R. Dilworth
  • Compositor OG Marcontell
  • Sound Designer William Hohauser
  • Associate Producer Bethany Cutmore-Scott, Elizabeth Cox
  • Content Producer Gerta Xhelo
  • Editorial Producer Alex Rosenthal
  • Narrator Susan Zimmerman
  • Fact-Checker Francisco Diez

More from Awesome Nature