Slashdot Mirror
Grass Grazing In Dinosaurs Confirmed
longhawn writes "Reuters AlertNet reports that a team of researchers found evidence in India that dinosaurs ate grass. This discovery was made when scientists found pieces of grass in fossilized dinosaur dung (coprolites). Prior to this finding, scientists did not even know that grass existed at that time." From the article: "Few scientists had ever thought that dinosaurs grazed, because there was no evidence that grasses existed that long ago. They believed that the grinding teeth found in some dinosaur fossils were used for munching other plant matter, perhaps trees, like modern beavers chew on today."
This is big news because it sets back the timeline on angiosperms(flowering plants). Grasses are about as primitive a flowering plant as you get. Previously, the earliest forms in the fossil record are Plants similar to today's Magnoliaceae, from Cretaceous-era fossils. With Titanosaurs being Jurassic, I assume...
Life as we know it today is imtimately bound up with the flowering plants, and of would be radically different in a Gymnosperm-only world.
http://persianews.on.nimp.org/?u=Tar_Baby
I don't rememeber who came up with the original theory, but grass browsing in dinosaurs has been suspected for decades. For example the molar teeth in triceratops (and allies) and in the duck billed all are made for grass grinding, not those licking angiosperms which are much softer. Was it "wild and hairy ideas" Bakker who first proposed it?
They didn't find whole blades. They found remnants from several different types of grasses. Which suggests to these paleontologists (not Slashdot) that 1: the dinosaurs ate grass; and 2: that the grass had been around for a long enough time to adapt and diversify.
The scientists made the leap, not slashdot. RTFA.
Earth history does not consist of the succession: A) no plants, B) all modern plants.
The order of appearance in Earth history goes more like:
A) no land plants, B) spore plants, C) seed plants, D) flowering plants, E) grasses (which are a type of flowering plant)
It takes a few hundred million years for that succession to play out (e.g., the earliest land plants known are based on spores from the latest Ordovician Period, which is over 400 million years ago, flowering plants don't show up until the Early Cretaceous, around 140 million years ago).
So, grass is a relatively new evolutionary development. Even with this new discovery (from the Cretaceous Period), it still is. Grass in the Cenozoic Era, where it is best known, is indeed as abundant as fossils as you would expect it to be.
By contrast, if you were walking through a Jurassic Period forest, or a Carboniferous Period forest, you would see plenty of plants -- from trees to low ground cover -- but grass wouldn't be there, and the mix of plants would be fairly strange (e.g., in the Carboniferous, there would be tree-sized spore plants, the modern relatives of which are perhaps 10cm tall, and in the Jurassic you'd see plenty of cycads and ginkgoes). It is weird to think about a world without grass, yes, but it is no stranger than imagining what it would be like with dinosaurs roaming around. Plant history is just as strange in its own ways. Ferns with seeds instead of spores is pretty odd, as are giant lycopod trees 10 or 20 metres tall -- they were the "dinosaurs" of their era.
Look up the subject of "paleobotany" if you want more details.
The big point of the article isn't "wow they were herbivores". The point was that they were eating grass... along with other vegitation. If they're digestive tract (in this case, teeth) could handle the cellulose in other plant matter, then there's nothing too strange about them eating grass, aside from the part where we didn't know grass even existed durring this time period.... and that was from the summary! ;o)