The first is that evolution contradicts the second law of thermodynamics, which states that the entropy of a closed system always increases. Entropy is a measure of randomness, and since life is a highly ordered state of matter, it is indeed likely that the earth's biosphere has a lower entropy now than the earth's surface before life began. This is not a contradiction to the second law of thermodynamics, however, since the earth receives energy continuously from the sun, and therefore is not a closed system. These are two overlapping sets of fossilized footprints, which some creationists have claimed are those of a human and a dinosaur. This would be inconsistent with normal science, which separates humans and dinosaurs by tens of millions of years.
Evolution is just a theory.
Actually, a general feature of science is that it only seeks provisional truth, not absolute truth. What usually happens instead is that a theory that was developed within a certain range of circumstances is found to be less accurate under other conditions. For instance, one of the most basic statements of chemical theory is that one element doesn't change into another lead doesn't turn into gold. In the 20th century it was discovered that elements could be transmuted, but only via nuclear reactions that take place under conditions of extreme temperature, not in ordinary chemical reactions. This doesn't make it any less foolish to try to turn lead into gold in a test tube.