The theory of plate tectonics explains the large-scale movement of Earth's lithosphere. While the timing and exact nature of the onset of plate tectonics are still subjects of scientific debate, it is widely considered to be a relatively recent phenomenon in Earth's history, occurring after the formation of the first life on Earth. Here are some key points regarding the timeline of plate tectonics and the origin of life:

1. Formation of the Earth: Earth formed approximately 4.5 billion years ago through the accretion and differentiation of cosmic material.

2. Origin of Life: The earliest evidence of life on Earth, such as microfossils and chemical signatures, dates back to about 3.5 billion years ago. These early life forms likely emerged in hydrothermal vents or other environments with favorable conditions.

3. Early Earth's Tectonics: The nature of tectonic processes during the early stages of Earth's history is still not fully understood. Some hypotheses suggest that Earth may have experienced different tectonic regimes before the onset of modern-style plate tectonics.

4. Onset of Plate Tectonics: The timing of the onset of modern plate tectonics is estimated to be around 3 billion years ago. This is based on geological and geochemical evidence, including the formation of stable cratons and the evolution of the Earth's magnetic field.

5. Feedback with Life: The emergence of plate tectonics had significant implications for the development and evolution of life. It created diverse environments and habitats, allowed for the transport of nutrients, and likely influenced the evolution of complex life forms.

Therefore, it is generally considered that plate tectonics was not occurring when life first formed on Earth, but that it emerged later in Earth's history, significantly shaping the conditions and environments that allowed for the evolution and diversification of life.