Well, it's been a while, but if I recall the lore correctly the reason there aren't any dragons in Morrowind/Oblivion was that the humanoid races already killed them all.
Nope.
Skylamps. They would actually be, moretheless, the Cliffracers. In short, the cliffracers came to Vvardenfell and pushed the dragons out. At one time, dragons flourished in Vvardenfell, being drawn to the comfort of the warmth in Red Mountain. The cliffracers grew in numbers (just as they appear to do in MW, since they seem to pop up behind you every 8 seconds). At first, this was not a problem for dragons. They were actually pretty good eating. But, just as a praying mantis is a big king of bugs, 1000 ants can easily take him. Thus, the dragons found themselves in a losing battle over the territory. Food sources and dwellings became overrun and the dragons simply packed their bags and moved on. The cliffracers plagued Red Mountain and in the end, drove the dragons out.
Some say the dragons moved on closer to Cyrodil, where they gained shelter and security from the Empire, along with dragons from other parts of Tamriel. Dragons are very sacred to the Empire, and as long as the Empire protects the dragons, the dragons MUST offer services to the Empire, such as aiding and protecting the Imperial forces in war (Redguard, the fight for Stros M'kai).
Just a little "in the know" for those who are curious about dragons. They DO exist, just not everywhere. Even in Cyrodil, where the majority of dragons may be, they are scarcely seen. Could it be they can shapeshift and use human form?
http://www.imperial-library.info/content/general-elder-scrolls-weaseling