4 ms·

Can you elaborate on 1) when the last time the earth saw temperatures like what are forecasted in the next 100 years (4-6 deg. celsius increase without large sc

Can you elaborate on 1) when the last time the earth saw temperatures like what are forecasted in the next 100 years (4-6 deg. celsius increase without large scale changes in energy consumption) 2) how much evidence exists that grasses because widespread above the k-t boundary 3) evidence that dinosaurs evolve to large sizes because they couldn't graze 4) evidence that there were not herbivorous large dinosaurs 5) evidence that ocean acidification is the cause of coral reef die-offs/bleaching 6) when jellyfish previous were an apex organism in the ocean ("take over the seas again")?

okmokmz 8y ago
Speaking to 5) "Warming causes coral bleaching (Figure 1C), which is the breakdown in the symbiosis between corals and their symbiotic dinoflagellates (zooxanthellae), which are essential for coral growth. Acidification decreases calcification and may ultimately result in the inability of corals to form a skeleton." [1] "Although higher pCO2 conditions do not appear to have a strong negative impact on physiological parameters, ocean acidification will have a negative impact on both colony and coral reef ecosystem scales. The reduction in calcification for these coral species will lead to generally weaker skeletons, increasing the risk of physical damage and bioerosion at the colony level" [2] [1] http://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.0060054 http://journals.plos.org/plosbiology/article?id=10.1371/jour... [2]https://s3.amazonaws.com/academia.edu.documents/46650429/Physiological_and_isotopic_responses_of_20160620-21973-1bw5zeb.pdf?AWSAccessKeyId=AKIAIWOWYYGZ2Y53UL3A&Expires=1533316555&Signature=2t4XwcmjF6eMy2YtoBV%2Bw%2BPqygk%3D&response-content-disposition=inline%3B%20filename%3DPhysiological_and_isotopic_responses_of.pdf https://s3.amazonaws.com/academia.edu.documents/46650429/Phy...
- deleted 8y ago
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AnimalMuppet 8y ago
Re 4: I don't think the claim was that there were not herbivorous large dinosaurs. I think the claim was that the herbivorous large dinosaurs were not grass-eaters.
- throwaway5752 8y ago
  Taken together, I hope it's clear that I'm not certain that evidence shows that grass co-evolved with radiative mammalian evolution post k-t. I could be wrong, but I'd like to have some references so I can be correct in the future, if that's the case. Are current and pre-holocene megafauna grass specific or generalist herbivores?
glenneroo 8y ago
Re #1: About 125,000 years ago[0] during the Pleistocene epoch. Wikipedia has a history of Earth's temperatures[1]. Somewhat related, XKCD[2] made a nice illustration to explain the temperature fluctuations of the last 22,000 years. [0]: http://science.sciencemag.org/content/355/6322/276 http://science.sciencemag.org/content/355/6322/276 [1]: https://en.wikipedia.org/wiki/Geologic_temperature_record#/media/File:All_palaeotemps.svg https://en.wikipedia.org/wiki/Geologic_temperature_record#/m... [2]: https://xkcd.com/1732/ https://xkcd.com/1732/

okmokmz 8y ago

Speaking to 5) "Warming causes coral bleaching (Figure 1C), which is the breakdown in the symbiosis between corals and their symbiotic dinoflagellates (zooxanthellae), which are essential for coral growth. Acidification decreases calcification and may ultimately result in the inability of corals to form a skeleton." [1] "Although higher pCO2 conditions do not appear to have a strong negative impact on physiological parameters, ocean acidification will have a negative impact on both colony and coral reef ecosystem scales. The reduction in calcification for these coral species will lead to generally weaker skeletons, increasing the risk of physical damage and bioerosion at the colony level" [2] [1] http://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.0060054 http://journals.plos.org/plosbiology/article?id=10.1371/jour... [2]https://s3.amazonaws.com/academia.edu.documents/46650429/Physiological_and_isotopic_responses_of_20160620-21973-1bw5zeb.pdf?AWSAccessKeyId=AKIAIWOWYYGZ2Y53UL3A&Expires=1533316555&Signature=2t4XwcmjF6eMy2YtoBV%2Bw%2BPqygk%3D&response-content-disposition=inline%3B%20filename%3DPhysiological_and_isotopic_responses_of.pdf https://s3.amazonaws.com/academia.edu.documents/46650429/Phy...

deleted 8y ago
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AnimalMuppet 8y ago

Re 4: I don't think the claim was that there were not herbivorous large dinosaurs. I think the claim was that the herbivorous large dinosaurs were not grass-eaters.

throwaway5752 8y ago
Taken together, I hope it's clear that I'm not certain that evidence shows that grass co-evolved with radiative mammalian evolution post k-t. I could be wrong, but I'd like to have some references so I can be correct in the future, if that's the case. Are current and pre-holocene megafauna grass specific or generalist herbivores?

glenneroo 8y ago

Re #1: About 125,000 years ago[0] during the Pleistocene epoch. Wikipedia has a history of Earth's temperatures[1]. Somewhat related, XKCD[2] made a nice illustration to explain the temperature fluctuations of the last 22,000 years. [0]: http://science.sciencemag.org/content/355/6322/276 http://science.sciencemag.org/content/355/6322/276 [1]: https://en.wikipedia.org/wiki/Geologic_temperature_record#/media/File:All_palaeotemps.svg https://en.wikipedia.org/wiki/Geologic_temperature_record#/m... [2]: https://xkcd.com/1732/ https://xkcd.com/1732/