Scientists put 3D glasses on cuttlefish

Scientists attached 3D glasses to cuttlefish to better understand the molluscs' visual perception as it relates to their ability to attack prey. They were treated to 3D screenings of shrimp while the University of Minnesota researchers studied their behavior. I wonder if, like me, the 3D movies gave them headaches. From the University of Minnesota:

The (shrimp) images were offset, allowing for the researchers to determine if the cuttlefish were comparing images between the left and the right eyes to gather information about distance to their prey. The process of comparing the images is called stereopsis, and is the same way humans determine depth. Depending on the image offset, the cuttlefish would perceive the shrimp to be either in front of or behind the screen. The cuttlefish predictably struck too close to or too far from the screen, according to the offset.

“How the cuttlefish reacted to the disparities clearly establishes that cuttlefish use stereopsis when hunting,” said Trevor Wardill, assistant professor at the Department of Ecology, Evolution and Behavior in the College of Biological Sciences. “When only one eye could see the shrimp, meaning stereopsis was not possible, the animals took longer to position themselves correctly. When both eyes could see the shrimp, meaning they utilized stereopsis, it allowed cuttlefish to make faster decisions when attacking. This can make all the difference in catching a meal.”

More: "Cuttlefish use stereopsis to strike at prey" (ScienceAdvances)

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