Sagebrush Herb
The sun is the major source of energy for organisms in an ecosystem. This energy flows in the food web and is being transformed from light energy into food energy through photosynthesis in plants, like the sagebrush.
In an ecosystem, there are a number of animals, called herbivores, who depend on plants for food. Aside from the herbivores, there are insects and bugs too that feed on plants. They are the organisms who eat plants as their energy source.
Beetles
As mentioned, most bugs and beetles feed on the leaves of the plants for their energy source. Other times, there are certain bugs and beetles too who are predators and feed on other insects too.
These bugs and beetles will also be consumed by birds, frogs, spiders and lizards in the food web.
Chuckwalla
A Chuckwalla is a type of lizard which is classified as a herbivore. It also feeds on the leaves of plants, and also the occasional insects that are found on the leaves, like the beetles.
Though there are no known predators of Chuckwalla, when they die, their bodies will be consumed by detritus. These are the organic matters that were produced during the decomposition of the organisms. Thus, when they die, their energy will be transferred to the detritus.
Kangaroo Rat
Kangaroo rat is a type of rodent that is primarily seed eaters, though they may also feed on vegetation. Thus, they source their energy from plants too.
Since it is a rodent, other wild animals like the snake, the eagle, foxes and many other predators that may feed on it and use it as an energy source.
Kangaroo
Kangaroos are herbivores too, though they sometimes feed on insects. They source their energy from grasses, flowers, leaves, ferns and moss.
Fortunately for the kangaroo, some of its predators, like the Marsupial Lion, the Megalania and the Wonambi, have already been extinct. However, there is still the wedge-tailed eagle and other raptors who eat kangaroo as their energy source.