The question about dinosaur hearts and the links there brought to mind a question I’ve been pondering for a while. I know that most fossils are found in pieces with bones scattered all over and missing. It seems like the really high quality fossils - such as those with intact organs, skin textures, etc. are only being found in the last twenty years or so, though. I seem to remember reading about the first fossilized skin just in the last few years
Is my impression wrong, or is there some reason, like better technology, that is improving the quality of fossil finds?
However, within the last (ten?) years paleontologists have realized where to look for them. There’s a mother-lode of them on the Montana-Manitoba border, where there was apparently some cataclysmic weather event that killed lots of hadrosaurs at once, and buried them under cold silt ‘just so’ so that a lot of them are “mummies” (an inaccurate term, but where lots of the tissue got fossilized in identifiable form as well as the bones). Other places that were marshy, with lots of cool rotting vegetation and sandy soil, have some mummies.
As well, it’s only been recently that paleontologists have realized how much of the mineral in a fossil is really part of the original dinosaur, and that inside the rib cage might even be a place one would look for evidence of fossilized organs. Or that one might look inside the fossilized bones for usable information (for instance, some of the evidence for warm-bloodedness are cavity patterns in fossils similar to modern warm-blooded bones. For instance two, there are tantalizing things in fossilized bones that seem a lot like marrow).
So it’s more like paleontologists today can get more out of each fossil.
I agree with bup, but will stress that it’s also a matter of chancing upon great fossil sites. For example, it’s only been in the last 15 years or so that scientists have explored the formations in Northeastern China that happen to have the right kind of preservation (still, silty lake bottoms combines with periodic volcanism and gas eruptions that kill all the fauna in their places and bury them quickly in fine-grained sediment) to preserve skin texture (feathers, etc.). These types of formations are incredibly rare and there are only a handful known in the world (some in Germany, where things like Archaeopteryx and Darwinius come from, are more examples). Sites like this can be so rich that fossils dug up in the '90s are still sitting in drawers waiting to be named and studied, creating a back catalog of amazing specimens that get meted out over the years, adding to the impression that we’re finding more well preserved specimens now than before.
These localized sites give us a handful of fossils that each provide a wealth of new information. Meanwhile, dozens of dinosaurs are still named each year for a few scattered vertebrae. So it’s a combination of knowing where and what to look for, and luck. (Not to mention the luck of getting to the really nice specimens before amateur collectors do, and they’re sold to private individuals at auctions or gem shows, and lost to science. There’s a massive “black market” in China where many of the best specimens are coming from, that’s only really illegal in name).
I’d also say the media has been doing more to bring attention to the really well preserved specimens, which wasn’t the case in the past. More scientists are actively seeking media attention for their finds. Paul Sereno’s Project Exploration is notorious for this. So, for example, when Carnotaurus was discovered in 1985 with nearly full-body skin impressions and excellent preservation, you were less likely to hear about it, and more likely to go on with the misconception that all fossil finds consist of a few toe bones.