When predators and prey face each other, the first move has generally been considered to be advantageous.However, many frogs, such as "snake-glared frogs," first stand still when faced with a snake, and only begin to escape after the snake begins to attack or reach close range.Snakes are often stationary in this situation, albeit slightly closer, sometimes for nearly an hour.So to speak, it is in a stalemate.

　This time, we made the Tonosama frog and the striped snake face each other under the laboratory experiment, and videotaped and analyzed the escape movement and the biting movement of the striped snake due to the jumping of the Tonosama frog.As a result, when the Tonosama frog jumped to escape when it was more than a certain distance away, there was a risk that the movement would be read and caught in the air.Once the striped snake started to bite, it was easy to read the course and avoid it.However, it was found that both players switched from the second move to the first move at a close distance (maai) where it was difficult to read the movement of the other party.

　Both sides make an appropriate decision as to whether they are the first move or the second move based on the ease of hitting the first strike of the striped snake, and at a distance where the Tonosama frog can dodge the first strike, both sides wait for the first move of the other. As a result of this, it was suggested that a stalemate would occur.

　Mr. Nishikai said that "a frog caught in a snake" may be biologically correct to use as a metaphor for a situation where "a frog is aiming at the moment when the garlic chives and the other party start to move in order to survive the crisis well". "No.

Paper information:[Canadian Journal of Zoology] A game of patience between predator and prey: waiting for opponent's action determines successful capture or escape