I did my thesis on Dinosaurs around the K/T boundary (Cretaceous-Tertiary) around the time when they went extinct. I looked a dinosaur eggs and looked for a correlation to see if their diet changed. Unsurprisingly it did. Right before their extinctions these dinosaurs I studied from Ancient France had their diet completely changed, and that I think is the key to understanding their extinction.
People like to blame the asteroid that hit the Yucatan Peninsula, but the asteroid alone doesn't explain the extinction. (Here is where the helmets come in.) Dinosaurs weren't killed off or rather go extinct (which is a genetic death rather than a physical one) because a huge rock impacted the Earth. It's the effects of that impact that likely killed off the Dinosaurs.
The media likes the asteroid story because it's flashy but the reality is that aside for the Dinosaurs in its path, the real trouble is the effect the asteroid had. And that's where we get into murky territory because nobody knows exactly. Most asteroid proponents for a time pushed the "nuclear-winter" option where the dust of the asteroid killed off sunlight to many areas. I dislike this because while dinosaurs went extinct amphibian which are way more sensitive than dinosaurs didn't suffer an extinction event.
What I suspect, and my thesis supports, is that after the asteroid hit (or before actually we don't know) the composition of plants that made up the dinosaurs changed drastically. Before the K/T times plant eating dinosaurs (and obviously those dinosaurs that ate the plant eaters) had diet base mainly of gymnosperms or trees or plants that reproduce via spores, like pine do today. This type of plant grows quickly (at least pines today do) and can grow massively big like the trees I saw in King's Canyon. You can imagine dinosaurs roaming the land when looking at those massive trees. The gymnosperms dominated the plant life of the planet (land) almost completely. But after the K/T that was no longer the case.
The rise of the fruit trees.
This I think is key: the dinosaurs went extinct right around the time the angiosperms (fruit and flower plants) came to rise. I think this caused an ecological crisis for the dinosaurs. The angiosperms were likely closely tied to the insects that pollinated them. Suddenly all that food that was going into the dinosaurs directly from plant mass was now diverted to small insects. Insects were now where the good food was, at a much smaller scale than before. I don't think it's coincidental that the two groups that came to rise after the dinosaurs are the mammals which are small, and many eat fruits and insects, and the birds (descendant from the dinosaurs) which eat sort of the same things.
Whatever actually happened to the environment suddenly flowering plants gained a huge advantage. Maybe it was something as simple as clearing long established forest, or disrupting the wind pollination of gymnosperms, whatever it was, the ecology of the world was forever changed with flowering trees (and grasses) dominating the plant landscape today.
This is something we should pay attention to closely. Forget the asteroid. Look at ecological change spelling disaster for the dinosaurs. Yet today when we wrestle with the ecological change being brought about by our own species, many discount the long lasting impact this may have. Just changing the composition of plant life on the planet doomed the dinosaurs to fossil-doom and gave rise to the mammals and birds. I wonder what changes a quickly warming planet will bring? All I know is that I wont wear a helmet just in case an asteroid falls from the sky.
Oh and just so you know amphibians, those guys that went through the Dinosaur extinction without a hitch, aren't doing to well with the rapid warming we're causing.
People like to blame the asteroid that hit the Yucatan Peninsula, but the asteroid alone doesn't explain the extinction. (Here is where the helmets come in.) Dinosaurs weren't killed off or rather go extinct (which is a genetic death rather than a physical one) because a huge rock impacted the Earth. It's the effects of that impact that likely killed off the Dinosaurs.
The media likes the asteroid story because it's flashy but the reality is that aside for the Dinosaurs in its path, the real trouble is the effect the asteroid had. And that's where we get into murky territory because nobody knows exactly. Most asteroid proponents for a time pushed the "nuclear-winter" option where the dust of the asteroid killed off sunlight to many areas. I dislike this because while dinosaurs went extinct amphibian which are way more sensitive than dinosaurs didn't suffer an extinction event.
What I suspect, and my thesis supports, is that after the asteroid hit (or before actually we don't know) the composition of plants that made up the dinosaurs changed drastically. Before the K/T times plant eating dinosaurs (and obviously those dinosaurs that ate the plant eaters) had diet base mainly of gymnosperms or trees or plants that reproduce via spores, like pine do today. This type of plant grows quickly (at least pines today do) and can grow massively big like the trees I saw in King's Canyon. You can imagine dinosaurs roaming the land when looking at those massive trees. The gymnosperms dominated the plant life of the planet (land) almost completely. But after the K/T that was no longer the case.
The rise of the fruit trees.
This I think is key: the dinosaurs went extinct right around the time the angiosperms (fruit and flower plants) came to rise. I think this caused an ecological crisis for the dinosaurs. The angiosperms were likely closely tied to the insects that pollinated them. Suddenly all that food that was going into the dinosaurs directly from plant mass was now diverted to small insects. Insects were now where the good food was, at a much smaller scale than before. I don't think it's coincidental that the two groups that came to rise after the dinosaurs are the mammals which are small, and many eat fruits and insects, and the birds (descendant from the dinosaurs) which eat sort of the same things.
Whatever actually happened to the environment suddenly flowering plants gained a huge advantage. Maybe it was something as simple as clearing long established forest, or disrupting the wind pollination of gymnosperms, whatever it was, the ecology of the world was forever changed with flowering trees (and grasses) dominating the plant landscape today.
This is something we should pay attention to closely. Forget the asteroid. Look at ecological change spelling disaster for the dinosaurs. Yet today when we wrestle with the ecological change being brought about by our own species, many discount the long lasting impact this may have. Just changing the composition of plant life on the planet doomed the dinosaurs to fossil-doom and gave rise to the mammals and birds. I wonder what changes a quickly warming planet will bring? All I know is that I wont wear a helmet just in case an asteroid falls from the sky.
Oh and just so you know amphibians, those guys that went through the Dinosaur extinction without a hitch, aren't doing to well with the rapid warming we're causing.
Very interesting. Do you have a copy of your thesis so that I can read more?
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