The discovery that dinosaurs of the Velociraptor type had ample feathers and looked more like ostriches than the slick beasts we have become accustomed to from the Jurassic Park movies was my favorite scientific finding of 2015.
The specific discovery was the genus Zhenyuanlong, but it tells a larger story. Feathered dinosaurs have been coming out of the ground in China almost faster than anyone can name them since the 1990s. However, it has taken a major adjustment to allow that the feathers on these dinosaurs mean that the equivalent dinosaurs in other parts of the world had feathers as well. The conditions in China simply happen to have been uniquely well suited to preserve the feathers’ impressions. That palaeontologists now know that even the Velociraptor type had feathers is a kind of unofficial turning point. No longer can we think of feathered dinosaurs as a queer development of creatures in East Asia. We can be sure that classic dinosaurs of that body type traditionally illustrated with scaly lizard-type skins—dino fans of my vintage will recall Coelophysis, Ornitholestes, etc.—had feathers. For example, other evidence of this kind came in 2015 too, including the discovery of strikingly extensive evidence of feathers on dinosaurs long known as the "ostrich-like" sort—Ornithomimus. Little we knew how close that resemblance was.
Who really cares whether Velociraptor had feathers, one might ask. But one of the key joys of science is discovering the unexpected. One becomes a dino fan as a kid from the baseball-card collecting impulse, savoring one’s mental list or cupboard of names and types. However, since the seventies it has become clear first that birds are the dinosaurs that survived, but then, even more dramatically, that a great many dinosaurs had feathers just like birds. This shouldn’t be surprising, but it is. Dinosaurs have gone from hobby to mental workout.
Second, the feathered Velociraptor coaxes us to tease apart the viscerally attractive from the empirically sound. The truth is that the sleek versions of bipedal dinosaurs look "cool"—streamlined, shiny, reptilian in a good way. Nothing has made this clearer than the Velociraptors brought to life in the Jurassic Park films. For these creatures to instead look more like ostriches, sloshing their feathers around and looking vaguely uncomfortable, doesn’t quite square with how we are used to seeing dinosaurs. Yet that’s the way it was. The sleek-looking Velociraptor, or little "Compies" of the Jurassic Park films (Compsognathus), or any number of other dinosaurs of that general build, are now "old school" in the same way as Brontosauruses lolling around in swamps (they didn’t) and Tyrannosauruses dragging their tails on the ground.
Finally, Velociraptor as ostrich neatly reinforces for us the fact that evolution works in small steps, each of which is functional and advantageous at the time, but for reasons that can seem quite disconnected from the purpose of the current manifestation of the trait. In life in general this is a valuable lesson.
In a language that marks articles, adjectives, and nouns with an arbitrary gender like Spanish (“the white house” is la casa blanca), the gender marking helps keep it clear how the words relate to one another. But such marking originates from a division of nouns into understandable classifications as "masculine" and "feminine" (or animal, long, flat, etc., depending on the language) whose literal meanings fade over time and just leave faceless markers.
In the same way, an ostrich-sized dinosaur with feathers rather clearly wasn’t capable of soaring like an albatross, which is one of many pieces of evidence that feathers emerged as insulation and/or sexual display, and only later evolved to allow flight.
Not that dinosaurs existed to compliment the aesthetics, tastes, and nostalgic impulses of observers millions of years after their demise, but feathered dinosaurs are tough to adjust to. Yet the adjustment is worth it, as it makes dinosaurs more genuinely educational in many ways.