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New Theory Suggests Dinosaurs Were Already Dying When Asteroid Hit (phys.org)
The new "biotic revenge hypothesis" suggests that dinosaurs were killed off by toxic plants. (And an inability to recognize the taste of a toxic plant.) the gmr summarizes a new paper reported at Phys.org:
The dinosaur population had been drastically decreasing before the asteroid impact, [and] the appearance of the first flowering plants -- angiosperms -- in the fossil record coincides with the gradual disappearance of the dinosaurs... The scientists concluded that though the asteroid played a role in the extinction of dinosaurs, the "plants had already placed severe strain on the species."
Crocodiles (believed to be descended from dinosaurs) also can't recognize the taste of toxic plants -- the researchers tested 10 different species. And they point out that not only did dinosaurs start to disappear before the asteroid impact -- they continued to "gradually disappear for millions of years afterward."
Crocodiles (believed to be descended from dinosaurs) also can't recognize the taste of toxic plants -- the researchers tested 10 different species. And they point out that not only did dinosaurs start to disappear before the asteroid impact -- they continued to "gradually disappear for millions of years afterward."
WOW! Someone made up more stupid RANDOM TRASH
Indeed. The paper is published by a psychologist, who is trying to psychoanalyse dinosaurs that lived 70 million years ago, when there is little evidence that psychoanalysis even works on living humans.
TFA contains some serious scientific illiteracy:
1. Dinosaurs are not "a species".
2. Crocodiles did not "descend from dinosaurs"
3. Plants would have no reason to evolve tasteless toxins, and there is no evidence whatsoever that they did.
Also, dinosaurs didn't go extinct. Some species died out, but other species survived. I have four small dinosaurs in my backyard, and they are very much alive. I keep them in my chicken coop, and their eggs are delicious. Much better than store-bought dinosaur eggs.
This may (although it doesn't, really) explain the decline of dinosaurs, but it says nothing about why thousands of other species (including all the ammonites) went extinct at the same time.
And the theory that dinosaurs were already dying off before the K/Pg boundary is hardly new. Part of that is an artifact of how fossils are formed and found. A species could have lasted several million years after its latest-known fossil, it just didn't happen to leave any fossils that have yet been found. (Conversely, the last surviving member of a species could have been fossilized. Unlikely though, except in the case of a mass extinction event.)
-- Alastair
The very first answer in the first link you posted answers the question:
<quote>Dinosaurs do not violate the square cube law.
Take the known strengths of bone and muscle, assume an animal shaped like the largest dinosaurs, apply the square cube law, and you get the maximum possible size and mass for an animal of that shape.
And, wait for it...
It turns out that maximum possible size and mass is just a tiny bit BIGGER than the biggest known dinosaurs!</quote>
Dinosaurs are a different shape to mammals.