The fossil record shows that living things have remained unchanged for tens or even hundreds of millions of years. This, by itself, is sufficient to demolish the theory of evolution. In addition, the absence of any "intermediate forms" (half-fish, half-reptile, or half-reptile, half-bird species) in the fossil record again gives the lie to the theory. Among all the millions of fossils belonging to thousands of living species obtained so far, there is not a single example of a life form that isn"t fully developed, or lacks certain attributes, that has remained halfway between two separate species. Every fossil shows that the living thing preserved is fully formed with all its characteristics, and that today"s descendants have never changed since the species first came into existence. The 45-million-year-old fossil pictured is one example, showing that gall gnats have not changed over that period of time.