Benton: 232 Ma coincides with Carnian pluvial episode; dinosaur explosion in steps (origin in early triassic, ~245 Ma; then 232 Ma, 225 Ma, and end Triassic 201 Ma) #lyell18
February 22, 2025 at 5:16 AM
Benton: 232 Ma coincides with Carnian pluvial episode; dinosaur explosion in steps (origin in early triassic, ~245 Ma; then 232 Ma, 225 Ma, and end Triassic 201 Ma) #lyell18
Percival: extinction appears to have ocurred differently from endMesozoic. Mesozoic style killer not present, extinction could have been due to orbital forcing of a climate destabilised by multiple long and short term factors #lyell18
February 22, 2025 at 5:11 AM
Percival: extinction appears to have ocurred differently from endMesozoic. Mesozoic style killer not present, extinction could have been due to orbital forcing of a climate destabilised by multiple long and short term factors #lyell18
Benton: but explosion of dinosaurs then rapid, both in diversity and disparity (Benton et al 2018 JGSL); inflection point at 232 Ma #lyell18
February 22, 2025 at 5:11 AM
Benton: but explosion of dinosaurs then rapid, both in diversity and disparity (Benton et al 2018 JGSL); inflection point at 232 Ma #lyell18
Lyell 2018 conference on mass extinctions
First speaker is David Bottjer: Biosedimentology of Mass Extinctions, #lyell18
What is biosedimentology and how it relates to mass extinctions? Biosedimentology are the biological processes that generate sediments
First speaker is David Bottjer: Biosedimentology of Mass Extinctions, #lyell18
What is biosedimentology and how it relates to mass extinctions? Biosedimentology are the biological processes that generate sediments
February 22, 2025 at 5:06 AM
Lyell 2018 conference on mass extinctions
First speaker is David Bottjer: Biosedimentology of Mass Extinctions, #lyell18
What is biosedimentology and how it relates to mass extinctions? Biosedimentology are the biological processes that generate sediments
First speaker is David Bottjer: Biosedimentology of Mass Extinctions, #lyell18
What is biosedimentology and how it relates to mass extinctions? Biosedimentology are the biological processes that generate sediments
Bottjer: 5 mass extinction, will focus here on end-Permian and end-Triassic
metazoan reefs are large scale ecosystem engineering. mediate physical, chemical and biological processes. microbial structures also represent biological engineering #lyell18
metazoan reefs are large scale ecosystem engineering. mediate physical, chemical and biological processes. microbial structures also represent biological engineering #lyell18
February 22, 2025 at 5:06 AM
Bottjer: 5 mass extinction, will focus here on end-Permian and end-Triassic
metazoan reefs are large scale ecosystem engineering. mediate physical, chemical and biological processes. microbial structures also represent biological engineering #lyell18
metazoan reefs are large scale ecosystem engineering. mediate physical, chemical and biological processes. microbial structures also represent biological engineering #lyell18
Bottjer: several intervals during early triassic with predominance of microbialites; later microbial-sponge reefs become more abundant. What was thought to be reef gap now seen as reef eclipse. Not a lot of metazoan diversity. #lyell18
February 22, 2025 at 5:06 AM
Bottjer: several intervals during early triassic with predominance of microbialites; later microbial-sponge reefs become more abundant. What was thought to be reef gap now seen as reef eclipse. Not a lot of metazoan diversity. #lyell18
Bottjer: when we look at modern seafloor bioturbation - even deep one - is abundant. This creates mixed layers. At end permian mass extinction/early triassic there is often lack of bioturbation, when bioturbation is present it's shallow. #lyell18
February 22, 2025 at 5:06 AM
Bottjer: when we look at modern seafloor bioturbation - even deep one - is abundant. This creates mixed layers. At end permian mass extinction/early triassic there is often lack of bioturbation, when bioturbation is present it's shallow. #lyell18
Percival: signal from various type of environmental data is conflicting, but there seems to be a growing signal for increased vulcanism in latest frasnian #lyell18
February 22, 2025 at 5:06 AM
Percival: signal from various type of environmental data is conflicting, but there seems to be a growing signal for increased vulcanism in latest frasnian #lyell18
Marshall: Forest evolution disrupted, this led to reduced runoff and other important ecological phenomena that may have caused disruption of terrestrial ecosystems #lyell18
February 22, 2025 at 5:06 AM
Marshall: Forest evolution disrupted, this led to reduced runoff and other important ecological phenomena that may have caused disruption of terrestrial ecosystems #lyell18
Benton: dinosaurs occupied distinct but small character space in late triassic, did not make headway for 25 my, and only took over after extinction of crurotarsan at end triassic #lyell18
February 22, 2025 at 5:06 AM
Benton: dinosaurs occupied distinct but small character space in late triassic, did not make headway for 25 my, and only took over after extinction of crurotarsan at end triassic #lyell18
Bottjer: in early triasssic the mixed layer was depleted or non-existent during early triassic.
Bottjer: long gaps in metazoan reefs after both end permian and end triassic extinctions. Microbialites become abundant; diminished mixed layer following extinctions #lyell18
Bottjer: long gaps in metazoan reefs after both end permian and end triassic extinctions. Microbialites become abundant; diminished mixed layer following extinctions #lyell18
February 22, 2025 at 5:00 AM
Bottjer: in early triasssic the mixed layer was depleted or non-existent during early triassic.
Bottjer: long gaps in metazoan reefs after both end permian and end triassic extinctions. Microbialites become abundant; diminished mixed layer following extinctions #lyell18
Bottjer: long gaps in metazoan reefs after both end permian and end triassic extinctions. Microbialites become abundant; diminished mixed layer following extinctions #lyell18
Mark Puttick: Searching for mass extinction drivers: common cause or lost cause?
Puttick: mass extinctions are a fact of life. What cause this? Number of causes have been suggested in past, are these acting alone or in combination? #lyell18
Puttick: mass extinctions are a fact of life. What cause this? Number of causes have been suggested in past, are these acting alone or in combination? #lyell18
February 22, 2025 at 5:00 AM
Mark Puttick: Searching for mass extinction drivers: common cause or lost cause?
Puttick: mass extinctions are a fact of life. What cause this? Number of causes have been suggested in past, are these acting alone or in combination? #lyell18
Puttick: mass extinctions are a fact of life. What cause this? Number of causes have been suggested in past, are these acting alone or in combination? #lyell18
Puttick: how can we link cause and effect? first step is establish periodicity signal in extinction, this done uwing databases like PaleoDB. Looked at marine invertebrates until Miocene #lyell18
February 22, 2025 at 5:00 AM
Puttick: how can we link cause and effect? first step is establish periodicity signal in extinction, this done uwing databases like PaleoDB. Looked at marine invertebrates until Miocene #lyell18
Puttick: periodicity in extinction suggested already by Raup & Sepkoski in 80s, then large number of studies on topic. Using a variety of methods to analyse data from last 350 my there is no support for periodicity in mass extinction #lyell18
February 22, 2025 at 5:00 AM
Puttick: periodicity in extinction suggested already by Raup & Sepkoski in 80s, then large number of studies on topic. Using a variety of methods to analyse data from last 350 my there is no support for periodicity in mass extinction #lyell18
Puttick: second step in study is statistically test links between extinction levels and drivers. For this sourced data on environmental variables such as CO2 ppm, 13C, sea level, continental fragmentation, LIP, etc. #lyell18
February 22, 2025 at 5:00 AM
Puttick: second step in study is statistically test links between extinction levels and drivers. For this sourced data on environmental variables such as CO2 ppm, 13C, sea level, continental fragmentation, LIP, etc. #lyell18
Marshall: some large plants are found above and below the boundary surviving the extinction, but in groups that compose the understory layer and the main forest trees disappear. #lyell18
February 22, 2025 at 5:00 AM
Marshall: some large plants are found above and below the boundary surviving the extinction, but in groups that compose the understory layer and the main forest trees disappear. #lyell18
Benton: archosauromorphs replaced therapsids, growing in size while therapsids got smaller; but was this due to random walk or was there selective pressure? #lyell18
February 22, 2025 at 5:00 AM
Benton: archosauromorphs replaced therapsids, growing in size while therapsids got smaller; but was this due to random walk or was there selective pressure? #lyell18
Puttick: there is little evidence for common causes. Lack of general link between extinctions could be due to scale of data being too coarse or to a lack of common drivers #lyell18
February 22, 2025 at 4:55 AM
Puttick: there is little evidence for common causes. Lack of general link between extinctions could be due to scale of data being too coarse or to a lack of common drivers #lyell18
Pimiento: Plio-Pleistocene marine megafauna saw disappearance of several taxa (large sharks, seaturtles, etc.). Using new statistical methods & data on origin and disappearance of marine megafauna allowed to identify extinction event during Pliocene (Pimiento et al 2017) #lyell18
February 22, 2025 at 4:55 AM
Pimiento: Plio-Pleistocene marine megafauna saw disappearance of several taxa (large sharks, seaturtles, etc.). Using new statistical methods & data on origin and disappearance of marine megafauna allowed to identify extinction event during Pliocene (Pimiento et al 2017) #lyell18
Percival: Devonian is an interesting time in earth's history, time of major tectonic and evolutionary activity; several biotic and environmental crisis throughout late devonian; continuous transgressions, gradual warming #lyell18
February 22, 2025 at 4:55 AM
Percival: Devonian is an interesting time in earth's history, time of major tectonic and evolutionary activity; several biotic and environmental crisis throughout late devonian; continuous transgressions, gradual warming #lyell18