The fossil record only has a fraction of species that have lived.
And many failures only lived a short time and there is no record of them.
There are more unknown failures than known successes.
So our perspective is skewed.
Maybe, but we can only work with what we can find, or at least get some evidence of. Consider "trace fossils" like footprints and burrows and excrement. In the early nineteenth century, someone once discovered footprints of giant birds. Or so it seemed. Those footprints were from the Mesozoic, and plenty of dinosaurs with birdlike feet were subsequently discovered. In fact, since birds are descended from dinosaurs, in a cladistic sense, they are still dinosaurs.
Or some mysterious stones found by eighteenth-century Europeans. They couldn't figure out what they were, until European explorers discovered people elsewhere in the world making similar stone objects. Those objects were then recognized as stone tools and weapons.
As to what's in the fossil record, bony vertebrates have wonderfully detailed skeletons, skeletons intimately associated with other body features, and one can learn a lot about their owners from them. If you look at the debate over whether dinosaurs were warm-blooded, you can see that the participants have a lot to work with.
I say bony vertebrates, because one cannot learn nearly as much about some vertebrates, like sharks. They have been around for some 400 million years, and numerous fossils of their teeth survive, but not much else (
Fossil Shark Basics – Discover Fishes). If there were no present-day sharks, sharks would be as mysterious as the owners of conodonts have been.
Turning to invertebrates, arthropods also have very informative skeletons, because their skeletons are their outer skins. Shelled mollusks' shells aren't very informative, because those shells have little connection with the rest of their owners' anatomy. Among them are the cephalopods, and present-day ones are divided into two groups, the nautilus, with a big external shell much like fossil cephalopods' shells, and coieoids, squid and cuttlefish and octopuses. Squid and cuttlefish have a vestgial bit of shell inside their bodies, while octopuses have none. Not surprisingly, fossils of octopuses are very rare.
See the Best Fossil Octopus Ever Found - Scientific American describes one of them.
To manipulate some object, one needs the ability to press different parts of one's body against opposite sides of an object. Human hands are well-adapted for manipulation, and we can make two kinds of grip with them. These are the power grip of fingers and palm, and the precision grip of thumb and index finger.
Does manipulating a wing for flight require less dexterity than a grasping hand?
For the wing you have the element of timing. It all has to be timed perfectly.
Not really. One does not need much precision if one is a small flier, like an insect. Birds and bats have wings that fold and unfold, while insects change the tilt of their wings -- insects do more wing control than vertebrates, it seems.
untermensche, why don't you look for slow-motion video of birds flying? It should be easy to do.
That is like using the body to throw a rock at an escaping prey. The whole body is involved and also is the element of timing.
Is the difference the use of vision?
You look at what you're manipulating with your hand or tentacle.
You do not look at the movement of a wing.
We have more senses than the traditional five, like proprioception, a fancy term for body-part-orientation sensing. Orientation like angles of limbs relative to each other. There is a classic test for drunkenness which consists of closing one's eyes and touching one's nose with a finger.
Prehensile tails are arguably kinds of tentacle. Not just spider and howler monkeys (Atelidae) have prehensile tails, but also opossums and seahorses.