Timeline - Scientific Date Discrepancies
The Urantia Book declares that material reality is upheld and controlled by spiritual reality, that it is spiritual reality that makes material reality possible. As such, spiritual intelligent beings administer and control the physical universe; such controllers can and do work from the subatomic level of material reality and above by manipulating forces and fields to perform their tasks, such as the materialization of matter into a star or nebula, and that these manipulations are undetectable by creatures such as we.
One of the measuring devices used by scientists to discern the dates of ancient events is through radiometric dating, measuring the rate of decay of radioactive elements. Physicists have concluded that this is a linear rate — their tests and reasoning can lead them to believe nothing otherwise; they must rely on what is evident, testable, repeatable.
The Urantia Book discloses a different construction to reality, one where the evident, testable, and repeatable is contained and controlled within a spiritual fabric; physical controllers can and do alter the conditions which affect radioactive decay for example.
The article by Dr. Chris Halvorson, The History of Life - https://urantiabook.org/archive/readers/halvorson_histlife.pdf - correlates a descending series of ratios between the linear rate of radioactive decay and the dates provided by The Urantia Book. He speculates that the reason the earlier dates given in The Urantia Book do not correspond one to one with scientific findings, and the reason these dates are revealed in the book in the first place, is to demonstrate that the Master Physical Controllers manipulate the environment that the solar system and planet earth occupy; that this environment was manipulated to decrease the surrounding higher energy levels in order to allow successively more sensitive and complex forms of life to evolve.