Rubbish. Some people claim evolution isn't an accurate picture of how life developed because there aren't any transitional fossils--creatures that are half reptile and half bird, for instance. That's simply not true.
There are many detailed examples of intermediate fossils. Perhaps the most famous fossils are from Archaeopteryx, which has the feathers and skeletal structure of birds and also features of dinosaurs.
There's a whole (ahem) flock of other feathered fossils, more and less like birds. There's a whole sequence of fossils spanning the evolution of modern horses beginning with the tiny Eohippus. Whales had four-legged ancestors that walked on land, and creatures known as Ambulocetus and Rodhocetus made the transition. Fossil seashells trace the evolution of various mollusks through millions of years. Perhaps 20 or more hominids (not all of them our ancestors) fill the gap between Lucy the australopithecine and modern humans.
And if all that isn't enough, there's definitive supporting evidence from molecular biology. All organisms share most of the same genes, but just as evolution predicts, the structures of these genes and their products diverge among species just as you'd expect from their evolutionary relationships. In fact, geneticists even have a technique that produces what amounts to a "molecular clock" that shows when various organism split off from earlier branches to form new species.
PS. This just in. Another transitional fossil between reptiles and mammals found. Stay tuned for more news as it happens. Film at 11.