Was the dinosaurs' extinction partly because of flowers? A new research suggests that their toxic meals were partly the reason why the asteroid that caused the dinosaurs' extinction was so successful at wiping them out.
It's difficult to say what exactly caused the dinosaur die out, but there are many theories on the matter, some of them rather unusual.
Biotic Revenge Hypothesis
The Biotic Revenge hypothesis was the main topic of a new study published in the journal Ideas in Ecology and Evolution. The hypothesis suggests that ancient plants are partly to blame for the dinosaur wipeout. Evidently, even after the rise of toxic angiosperms, the dinosaurs still kept on eating the plants because they haven't yet developed taste aversion and because they needed to keep on consuming large amounts of plants to sustain their energy needs. Unfortunately, their lack of taste aversion led to the creatures eating lethal amounts of toxic plants.
That's not saying the theory suggests that dinosaurs weren't rendered extinct by a massive asteroid. In fact, it supports the currently held theory, but the hypothesis simply suggests that at the time that the asteroid hit, the herbivores were already in decline because of their toxic meals, and as such, the carnivores were shrinking in numbers as well.
The hypothesis may sound rather unusual to some, but there are other hypotheses on dinosaur extinction that are rather interesting as well. Unlike the new hypothesis, however, many of them have already been discarded and debunked.
It seems rather unusual to blame caterpillars for the dinosaur extinction, but a 1962 paper by entomologist Stanley Flanders suggested that caterpillars might have devastated the Cretaceous vegetation, leaving the herbivores to starve. As the herbivores slowly died out, the predators were left to eat each other.
However, butterflies and moths actually coexisted with dinosaurs for millions of years, and there is no evidence of a caterpillar spike in the fossil records.
In 1982, ophthalmologist L.R. Croft suggested that dinosaurs with horns and crests developed the features as a means to protect their eyes from the sun. However, because the sun at the time was still much too harsh, the horns still weren't enough to protect their eyes, and the creatures began to go blind even before reaching sexual maturity.
However, as interesting as the hypothesis is, it does not explain the mass extinction of other dinosaur species.
They Ate Their Eggs To Extinction
Twentieth-century paleontologist George Wieland once argued that the dinosaurs loved eating eggs and that even some dinosaur mothers could not protect their young. However, his 1925 hypothesis about how dinosaurs might have eaten themselves to extinction was unsupported by fossil records that show that while snakes and dinosaurs did indeed prey on eggs and dinosaur young, it was not to a rate that they caused their own mass extinction.
In the 1900s, there was a belief that perhaps the dinosaurs experienced an evolutionary inertia that led to them getting bigger and bigger but less adaptable to the changing environment. Further, they were believed to be rather less intelligent than the mammals because their evolution was focused solely on growing bigger and fiercer.
However, this does not explain why several massive dinosaur species actually thrived for quite a long period.