How do lizards find food to eat? - Science Journal for Kids and Teens

Have you ever seen a lizard or snake flick its tongue in and out? This behavior is part of how they smell. These animals have a special organ at the top of their mouths called the vomeronasal organ. When a lizard sticks out its tongue, the tip picks up scent molecules from the air. When the tongue is pulled back in, the lizard presses it to the roof of its mouth, delivering scents to the vomeronasal organ. This process, called vomerolfaction, lets them detect a wider range of smells than they can with just their noses.

One lizard that uses this skill is the Guatemalan beaded lizard. It is one of the rarest animals in the world, with only about 600 individuals living in the wild. They are found in only one place: the thornscrub ecosystem of the Motagua Valley in Guatemala. They are also one of the only venomous lizard species. We know they eat things like bird and lizard eggs, insects, baby birds, and small mammals. But what strategy do they use to find this food? Do they follow a specific plan when they search, or is their movement random? A team of scientists designed an experiment to find out.

The scientists carried out a series of maze experiments using an 8-armed maze. Their test subjects were five Guatemalan beaded lizards from Zoo Atlanta. Before starting, the scientists observed the lizards for signs of stress and let them explore the maze to get comfortable.

They conducted three different experiments.

Experiment 1 tested if lizards can keep track of where they have already searched. The scientists placed a small treat (a piece of mouse or raw scrambled egg) at the end of all eight passages in the maze.

Experiment 2 tested if lizards can smell food from a distance. The scientists blocked off most of the maze, leaving only a simple T-shaped path. They placed a treat in just one of the two end passages, forcing the lizard to choose left or right based on scent from a distance.