I believe the answer is Sunlight.
In our world, the bimass of plants (which considered as living things) make up 1000 more population compared to another living organism.
The plants get their food mainly from the photosynthesis process that utilize Sunlight, water, and other nutrients from soil.
Pandemics occur over a wide geographic region, potentially affecting a large population.
Like all animals the noises they make are to warn off predators, and mating call. IDk
