Here's why:

* Early Earth: The early Earth was a harsh environment, devoid of oxygen. Bacteria were the first life forms to evolve and thrive in these conditions. They were single-celled organisms capable of surviving without oxygen.

* Photosynthesis: Over time, some bacteria developed the ability to perform photosynthesis, a process that uses sunlight to create energy and produce oxygen as a byproduct. This was a groundbreaking development, as it slowly transformed Earth's atmosphere and paved the way for more complex life.

* Evolution of Plants: Plants evolved from single-celled, photosynthetic organisms. They eventually became multicellular and developed complex structures like roots, stems, and leaves.

Therefore, bacteria existed long before plants evolved. They played a crucial role in shaping Earth's environment and making it suitable for the development of other life forms, including plants.