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Post by HRH Queen Talira on Jun 11, 2018 5:19:49 GMT
There are three current theories to explain the extinction of the dinosaurs at the end of the Cretaceous. They are:
1. Climate change The climate changed as the supercontinent Pangaea broke up. By the end of the Cretaceous, global temperatures were falling and differences between summer and winter temperatures were becoming more pronounced. Plants were also changing to suit new environments. Perhaps dinosaurs couldn't cope with these environmental changes.
2. Increased volcanic activity At the end of the Cretaceous, several parts of the world, particularly the landmass that would become India, were experiencing vast amounts of volcanic activity.
3. Impact of a comet or asteroid This is the most dramatic theory and it's supported by several lines of evidence, including the existence of Cretaceous sediments rich in the element Iridium. In 1990, on Mexico's Yucatan Peninsula, came the discovery of a possible impact site.
Which theory do you believe?
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Post by HRH Queen Talira on Oct 14, 2018 6:19:22 GMT
Another more unlikely theory is that some of the vegetation became poisonous. A number of modern plants including Mistletoe, Blue passion flower and Yellow oleander have toxic fruit, seeds or leaves, to protect themselves from being eaten. Perhaps some of the plants that evolved towards the end of the Cretaceous produced similar poisons.
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Post by magicmuggle01 on Oct 14, 2018 19:33:02 GMT
Another more unlikely theory is that some of the vegetation became poisonous. A number of modern plants including Mistletoe, Blue passion flower and Yellow oleander have toxic fruit, seeds or leaves, to protect themselves from being eaten. Perhaps some of the plants that evolved towards the end of the Cretaceous produced similar poisons. I could understand this theory for the herbivores but what about the carnivores? Unless you're talking about carnivores eating the flesh of the poisoned herbivores and dying that way. At the moment I'd opt for at least a mixture of an asteroid impact leading to climate change eventually leading to an ice age wiping out the dinosaurs that way since most of them would have been used to a lot warmer climate.
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