An article over at the Cornell Chronicle looks into the issue of "cultural inertia" in our understanding of dinosaurs. When asked to draw a T. rex, perhaps the most well-known (in popular culture) of all dinosaurs, both young children and college students will draw an upright, small-armed, tail-dragging creature that looks like a slimmed-down Barney or a less-plasticky Rex from Toy Story.
But in fact, we've known for decades that the T. rex did not stand upright, but that its posture was much more horizontal. Even in Jurassic Park, the T. rex was portrayed reasonably in line with current scientific understanding of the animal.
And yet our perception of the dinosaur is still stuck, similar to what was thought of it in the early 20th century, well before the "dinosaur boom" of the 1960s and '70s. Cornell suggests that this is due to improper imprinting--Toy Story and Barney both get to kids early, leaving their ingrained understanding of dinosaurs incorrect. Read more over at Cornell.