Adaptations and Ecological Role
Bearded dragons' natural habitat is incredibly hostile to most forms of life. Deserts are dry, hot, and have larger predatory animals that prey on these lizards. In order to survive in this environment, bearded dragons have some unique adaptations that help them survive and body systems that help them play their ecological role. Bearded dragons "have an extendable pouch under their jaw" (Team, n.d.) that can be inflated to make it seem like the lizard is significantly larger than it actually is. The beard also has the ability to change colour to a near complete black when the lizard feels threatened which acts as a further predatory detterent (Team, n.d.). Also, bearded dragons have a unique sensory organ called the paretial eye. This organ is also sometimes reffered to as the third eye and it is located on the top of their head. It has a "rudimentary retina and lens, along with a cluster of light-sensitive cells" (Westmaas, 2018) which allows the bearded dragon to detect changes in light. This organ serves different purposes including predator detection (ie. a bird overhead), tracking the sun during the day which is incredibly important as they are ectothermic, and as a means to navigate their environments (Westmaas, 2018).
Bearded dragons have many different body systems that allow them to play their ecological role. Since bearded dragons live in desert environments that have very little water, they almost exclusively get their water from the prey and plants they eat and are extremely good at extracting water from their food (Bearded Dragon Care 101, n.d.). Bearded dragons also have to monitor their energy expenditure during daylight hours since food is hard to come by in the desert. Bearded dragons are also capable of slowing their metabolisms down during colder periods to not expend too much energy (Stacey, 2019). By doing this, it allows them to save their energy for times when they are hunting or running away from predators. Finally, bearded dragons live in desert climates which can be very hot during the day but also get very cold during the night. They use their paretial eye to track the sun and ensure that they will be warm enough and have enough time to find a place to hide before night comes (Westmaas, 2018).