Really interesting. Tonight I intended to discover my favourite dinosaur, but I'm in danger of deciding on a favourite extinction event instead!
@holozoan
2 жыл бұрын
You're a great teacher, Phoebe!
@footfault1941
4 жыл бұрын
A charming scientist in the spotlight. The subject has a very long history of presentation/lecture etc., that is, for some might be 'fed up' with it. Her presentation refreshes interest in this important theme in evolution. Well done! By the way, I'm curious about how quickly/slowly recovered those who weathered mass extinction. Or emergence of new species. This is predictably difficult to study though.
@AnkitRaj-pg1sp
5 жыл бұрын
Hope professors like you may be there in India also. Good to know the topic by you ma'am.
@wade5941
5 жыл бұрын
I have always found it interesting that life exploded on the scene during a period (Cambrian) that coincides with the planets highest temperatures and CO2 levels. Conversely, the Permian Extinction initiated during a time when mother Earth's temps and CO2 levels were the lowest over the last million years.
@davetheraveist3949
5 жыл бұрын
The end Permian extinction was preceded by a spike in CO2 and an increase in ocean temp. Thought to be caused by the Siberian traps volcanic event it was climate change in a geological instant yet over a far longer timescale than we're seeing now. phys.org/news/2014-02-end-permian-extinction-yearsmuch-faster-earlier.html
@misterguts
5 жыл бұрын
Ergo, high levels of CO2 and high temperatures are actually good for you. Quit complaining about climate change, it will actually be very nice!
@davetheraveist3949
5 жыл бұрын
@@misterguts Not too bright are you?
@ManicMercurianAstrology
3 жыл бұрын
@@misterguts yeah warmer temperatures would actually be stabilizing for the climate, especially considering the recent glaciations we've been experiencing
@nyoodmono4681
4 жыл бұрын
Thank you i learned a lot! Props on your take on the "6th mass extincton"
@rapauli
6 жыл бұрын
Thanks for this. However, just because you don't have enough info to decide that we are into a sixth mass extinction does not mean it is not so. It only means that you have insufficient information to make a pronouncement. This talk was given 3 years ago.. I will look for subsequent work that might have more to say about this. Thanks for this talk.
@garymingy8671
4 жыл бұрын
Things that we have a lack of evidence for , it's preferable to pretend they don't exist , you don't want to influence your data collection , as an aside - the planet will be fine , life my cease , but as a geologists ,well I don't care ,not my department , told ya so long ago . See ya in hell !
@CandideSchmyles
5 жыл бұрын
Now that game of thrones is over maybe phoebe can give more and more in depth videos now she no longer has to double for the queen of dragons. Im not sure if it exists but if it does and someone knows please tell me where I can see it. What I want to see is a comparative core analysis of multiple global locations looking at microfossils in the 5myr zone either side of the K-pg. Especially interested in anything from the Arabian Sea and the Caspian.
@rjelkins
4 жыл бұрын
Excellent talk although I had to dial the playback speed down to 0.75. fast talker!
@oobrocks
3 жыл бұрын
This won't ever be on tv; college level course
@edbaisley5805
2 жыл бұрын
Great presentation but who did the art behind you….
@ennc3
5 ай бұрын
Great teacher and Lecture! just needs to stop drinking into a sensitive mic. Or edit it out.
@rajendrakumarghatage2744
3 жыл бұрын
17:20 wouldn't it be prudent to build a simulation to know the exact location of the fossil in that period as we know land mass drifts and plate tectonics affects long term location, or has it been taken into account to determine that tropical locations had had high probability of extinction ?
@DidivsIvlianvs
5 жыл бұрын
8:40 "changes" s/b chances
@perrinpartee557
7 жыл бұрын
So cool
@fernandoleon6875
6 жыл бұрын
She is great.
@claudiohess7692
6 жыл бұрын
So many data collected makes such a dense presentation!!! Wonderful! Some presentation teacher has to help Phoebe to control her throat cleaning, drinking and too many OKs. Sometimes she is talking too fast, but this is a long presentation anyway!! Wonderful work!!!
@rameyzamora1018
5 жыл бұрын
Points of interest but I wish repetitive prosody would go extinct, too.
@ncdave4life
6 жыл бұрын
The supposed harms from reducing ocean pH, to the tiny degree that mankind can plausibly do it, are purely hypothetical, and largely implausible. (Note that the oceans are alkaline, not acid, and no amount of CO2 emissions can change that; additional dissolved CO2 just makes seawater slightly less caustic.) The greatest effect of atmospheric CO2 level change is on surface water, but AR5 estimates that the average pH of ocean surface water has decreased by just 0.1 since the beginning of the industrial age. Ocean pH variations with time, location, basin & depth are all much, MUCH greater than that tiny change. Yet those much larger pH variations do not seem to cause any problems for marine life. Look how much pH varies with depth in the North Atlantic and North Pacific, and look how different the pH profiles in the two basins are from each other: sealevel.info/pH-TCO2_NAtlantic_NPacific_vs_depth.png Note that there's 50× as much CO2 dissolved in the oceans as there is in the air, and only about 1/4 of the CO2 which mankind emits ends up in the oceans. So CO2 emissions have only a slight effect on the oceans. Also, ocean chemistry buffers changes in pH due to carbonic acid from dissolved CO2. Plus, higher levels of dissolved CO2 stimulates the growth of calcifying coccolithophores, which, when they die, carry calcium carbonate to the ocean depths, thus reducing levels of dissolved CO2 (a negative feedback mechanism). This effect is surprisingly large; here are some references: hub.jhu.edu/2015/11/26/rapid-plankton-growth-could-signal-climate-change www.sciencedaily.com/releases/2015/11/151126165042.htm www.techtimes.com/articles/111246/20151127/rapid-growth-of-plankton-caused-by-increased-carbon-levels-in-the-ocean.htm www.academia.edu/13761237/Origin_and_Evolution_of_Coccolithophores_From_Coastal_Hunters_to_Oceanic_Farmers Ideal atmospheric CO2 level for most plants is around 1500 ppmv. Unfortunately, mankind can probably never get the outdoor level to even half that. Here are some references: www.researchgate.net/publication/303621100_The_implications_of_fossil_fuel_supply_constraints_on_climate_change_projetions-A_supply-side_analysis www.sciencedirect.com/science/article/pii/S0016328715300690 sealevel.info/feedbacks.html#greening
@DidivsIvlianvs
5 жыл бұрын
Also, if you really really pump up ocean CO2, it combines with calcium and precipitates out. --- Never mind. I see you already said that.
@DidivsIvlianvs
5 жыл бұрын
Here is the problem with CO2 CAUSING the PT extinction: If you release 4400 GT of CO2 over, say, 100,000 years, that is only 44 million tonnes per year. That is 1/25 of humanity's emission rate and a rounding error in the global carbon budget. There is only one way you can get that little bit to accumulate in the atmosphere: that plants that would have used it were ALREADY DEAD. Ooops. It is just like the CO2 buildups that happen 800 years AFTER glaciers melt.
@garymingy8671
4 жыл бұрын
Yes mankind is small weak an feeble ; we can't change the ocean , and farming in land , some city's an roads , moslty inert , 85% uneffected.
@yoransom
5 жыл бұрын
39:55 what a dumb fuckin map
@lawxx6
Жыл бұрын
Another future event will be 2028 until then keep your thinking hats on we will need a great mind soon
@kennethwers
7 жыл бұрын
10;30 Super White Fred? Not a bit racist!!
@TKO67
6 жыл бұрын
super wide spread
@captainthrall
6 жыл бұрын
Fantastic information - mediocre presentation
@DidivsIvlianvs
5 жыл бұрын
Ginkgo doesn't change for hundreds of millions of years. New species appearances turn on and off. God is trying to tell you something about evolution... The Co-Evolution of Earth and Life... more like deliberate terraforming. She really did say, "How you create a world where that happens." 33:30
@TKO67
6 жыл бұрын
Earth is 6,000 years old
@DangerousFacts48
6 жыл бұрын
Lol
@ByronWalter
6 жыл бұрын
Correct... but you should include an error range of around ± 4.5 billion years.
@TKO67
6 жыл бұрын
that would apply for so called eviloution.
@ByronWalter
6 жыл бұрын
Evolution and the age of the earth are separate topics... although they are related. I guess that you are relying on a 2000 year old book on religion as being a replacement for science. It's fine for religion but probably not so great as explaining issues involving geologic time and evolution.
@TKO67
6 жыл бұрын
science is not what evolution is based on. Your right just like evolution is a religion because there is no proof. No transitions between a rock and human.You have to have faith just like any other religion.
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