Ever since Michael Crichton published Jurassic Park in 1990, followed by the classic Spielberg film three years later, there has been a popular urban legend that blood-engorged mosquito fossils are common and that a real Jurassic Park is possible someday. In fact, fossilized mosquitoes are fairly rare, and even rarer are fossils of mosquitoes or other blood-sucking insects where there is evidence of blood in their stomachs from their latest victim—to date what has been discovered is only a couple mosquito fossils (one was discovered recently), a few sandflies, and an assassin bug.
Unfortunately being able to extract DNA from blood that is now fossilized is a complete fantasy. So there never will be a Jurassic Park, except at the movies.
