Discontinuous fossil sequences. E.g. Coelacanth, Wollemi pine and various “index” fossils, which are present in supposedly ancient strata, missing in strata representing many millions of years since, but still living today. Such discontinuities speak against the interpretation of the rock formations as vast geological ages—how could Coelacanths have avoided being fossilized for 65 million years, for example?

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Science is based on observation, and the only reliable means of telling the age of anything is by the testimony of a reliable witness who observed the events. The Bible claims to be the communication of the only One who witnessed the events of Creation: the Creator himself. As such, the Bible is the only reliable means of knowing the age of the earth and the cosmos. In the end we believe that the Bible will stand vindicated and those who deny its testimony will be confounded.

Source: Creation.com