Neogene Worlds, Life & Extinctions Norman MacLeod School of Earth Sciences & Engineering, Nanjing University Neogene World, Life & Extinctions Objectives Understand the structure of the Neogene world in terms of timescales, geography, environments, and organisms Understand the structure of Neogene extinction events Understand the major Neo- gene extinction drivers Understand the degree to which these putative drivers correlate with Neogene extinction events. Neogene World, Life & Extinctions Presentation Topics Stratigraphy - chronostrati- graphy & geochronology Geography - tectonics & distribution Climate - circulation, temp- erature, weather Biota - protists, invertebrates, vertebrates, plants Evolution - evolutionary faunas, adaptive radiations, major innovations Significant Events - sea-level changes, volcanic eruptions, marine anoxia events, bolide impacts, extinctions 80 Paleozoic-Cenozoic System Durations 64 Phanerozoic 48 Duration32 (myr) 16 0 Camb. Ord. Sil. Dev. Carbon. Perm. Trias. Jur. Cret. Paleog. Neog. Pleist. Data from ICS (2019) Neogene Cenozoic Epoch Durations 25 20 15 10 Duration(myr) 5 0 Paleocene Eocene Oligocene Miocene Pliocene Data from ICS (2019) Neogene Timescale System Series Stage Mya 2.58 Piacenzian 3.60 Pliocene Zanclean 5.33 Messinian 7.25 Tortonian 11.63 Serravallian Miocene 13.82 Neogene Langhian 15.97 Burdigalian 20.44 Aquitanian 23.03 Data from ICS (2019) Neogene Neogene Tectonic Configuration Continents continue to drift toward their present positions. Land bridge between North America and South America forms during the Pliocene due to sea-level fall. Mountain ranges appear on almost all continents owing to tectonic collisions Establishment of modern tectonic & subductions. plate configurations and establish- Tectonic collision between ment of modern atmospheric and Africa and Europe caused marine circulation patterns. Mediterranean Sea to dry up in Messinian. Map from Scotese PaleoMap Project (2001) Neogene Marine Circulation Five permanent subtropical gyres. Northern hemisphere types rotate clockwise, souther hemisphere gyres rotate counterclockwise under Coriolis Effect. Boundary currents move water between the major ocean gyres. Essentially a modern marine Vertical circulation circulation pattern with variations in controlled by deep-ocean intensity conditioned on variations in conveyor which was sea level, the latitudinal thermal established in the gradient, and global temperature. Neogene. Neogene Marine Circulation Five permanent subtropical gyres. Northern hemisphere gyres rotate clockwise, southern hemisphere gyres rotate counterclockwise under Coriolis Effect. Boundary currents move water between the major ocean gyres. Vertical circulation controlled by deep-ocean conveyor which was established in the Neogene. Map from Avsa (2009) Neogene Marine Themohaline Circulation Video from NASA (2009) Neogene Paleoenvironment Atmospheric O Atmospheric CO 2 2 35 5000 28 4000 21 3000 14 2000 7 1000 Percent byVol. Parts PerMillionParts 0 0 Cb. Od. Sl. Dv. Cr. Pm. Tr Jr Ct Pg Ng Cb. Od. Sl. Dv. Cr. Pm. Tr. Jr. Ct Pg Ng Mean Surface Temperature Sea Level 25 250 20 200 15 150 Present 10 100 Meters Above Meters Degrees Celsius 5 50 0 0 Cb. Od. Sl. Dv. Cb. Pm. Tr. Jr. Ct. Pg Ng Cb. Od. Sl. Dv. Cr. Pm. Tr. Jr. Ct. Pg Ng Neogene Climate Zones Comparative Criteria Neogene O2 Content of 21.5 vol. % Atmosphere (108%) CO2 Content of 280 ppm Atmosphere (x1) Mean Surface 14°C Temperature (0°C) Sea Level +150 m to -100 m Climates remained relatively warm throughout the Early Miocene with a slow cooling trend that ended with two sharp drops in global temperature, one in the Middle Miocene (c. 14 mya) and the other in the Late Miocene (c. 8 mya). Map from Scotese PaleoMap Project (2000) Neogene Global Temperature Variation Diagram from Zachos et al. (2008) Neogene Miocene Vegetation Model Map from Micheels et al. (2007) Neogene Miocene Sea Surface Temperatures Map from Tim Herbert Lab, Brown University Neogene Pliocene Climate Zones Map from US Geological Survey (USGS) Neogene Pliocene Sea Surface Temperatures Map from US Geological Survey (USGS) Paleogene Cambrian Evolutionary Fauna X X Trilobite Graptolite Inarticulata Monoplacophora Polychaete Neogene Paleozoic Evolutionary Fauna Articulata Crinoid X X X Tabulate Coral Bryozoan Ammonite Rugose Coral Neogene Modern Evolutionary Fauna Bivalve Gastropod Echinoid Bony Fish Neogene Reefs Pliocene Reef Widespread reef formation around throughout the Tethys, the proto- Gulf of Mexico, across southeast Asia and around Pacific islands. Quite a hemispherically symmetrical latitudinal distribution with reefs extending to above 60° latitude, bit more reefs in northern hemisphere indicating a latitudinally asymmetrical distribution of shallow marine habitats and sea-surface temperatures. Map from Scotese PaleoMap Project (2000) Neogene Fish Ophiodon Acanthurus Pseudovomer Hippocampus Oncorhynchus Neogene Elasmobranchs Carcharocles megalodon Carcharhinus Manta Hemipristis Megalolamna Neogene Terrestrial Environment Miocene Grassland Biome Neogene Terrestrial Environment Plants Arthropods (incl. insects) Amphibians Reptiles Birds Mammals Miocene Terrestrial Scene Global climates become more seasonal with a larger latitudinal thermal gradient with a continuation of the cooling and drying trend that began in the Eocene. Ice caps at both poles grow and thicken along with the Greenland ice cap and mountain glaciers worldwide. Alternating massive glacial-interglacial phases begin at the end of the interval. Neogene Trees Northofagus Quercus Pinus (Beech) (Oak) (Pine) Magnolia Ginkgo Metasequoia (Magnolia) (Ginko) (Metasequoia) Neogene Terrestrial Insects Acanthognathus Lutzomyia Curitiba Anochetus Neogene Terrestrial Arthropods Archaeogeryon Tityus Ischnocolinopsis Anbarrhacus Unnamed Isopod Xantho Neogene Quadrupeds (Amphibians) Palaeoplethodon Palaeobatrachus Mioproteus Bombina Neogene Quadrupeds (Reptiles) Meiolania Crocodylus Rhamphosuchus Liasis Pumilia Neogene Quadrupeds (Mammals) Aepycamelus Rhynchotherium Pliohippus Chalicotherium Neogene Quadrupeds (Mammals) Aepycamelus Cuvieronius Pliohippus Chalicotherium Neogene Mammals (Whales) Brygmophyseter Balaenoptera Neogene Quadrupeds (Birds) Pelagornis Osteodontornis Titanis Bathornis Neogene Phorusrhacidae (Terror Birds) An extinct clade of large flightless birds that were the top predators in many South American Paleogene terrestrial environments. Restricted to the island continent of South America throughout the Paleogene, these predators invaded North America in the Neogene via the Panamanian land bridge. Fast, agile runners, these birds probably took prey considerably smaller than themselves owing to a comparatively small bite force. Since all birds and direct descendants of dinosaurs the presence of these birds lends support to the argument that dinosaurs played a considerable ecological role, first in S. America and later throughout the western hemisphere, throughout most of the Cenozoic. Neogene Biodiversity 800 600 400 Modern Fauna 200 Paleozoic Fauna NumberFamilies of Cambrian Fauna 0 Cambrian Ordovician Sil. Devonian Carbon. Permian Tri. Jurassic Cretaceous Tertiary 500 400 300 200 100 0 Geological Time Data from Sepkoski (1981) Neogene Extinctions End-Ordovician End-Devonian End-Permian End-Triassic End-Cretaceous 80 Palaeozoic Mesozoic Cenozoic Neogene 60 40 PercentExtinction 20 0 Cambrian Ord. Sil. Dev. Carb. Perm. Trias. Jurassic Cretaceous Paleoc. Neo. Paleozoic Mesozoic Cenozoic Data from Sepkoski (1998) Neogene Extinction Events System Series Stage Mya 2.58 Great American Biotic Piacenzian Interchange (GABI) 3.60 Pliocene Zanclean 5.33 Messinian 7.25 Tortonian 11.63 Serravallian Miocene Local mammalian & 13.82 benthic invertebrate Neogene Langhian extinctions 15.97 Mostly local terrestrial extinctions in Europe (lizards, Burdigalian alligators, turtles) 20.44 Aquitanian 23.03 0 4 8 12 16 20 % Extinctions Neogene Environmental Events System Series Stage Mya 2.58 Land bridge emerges Piacenzian between North and South 3.60 America Pliocene Zanclean 5.33 Messinian Messinian Salinity Crisis 7.25 Tortonian 11.63 Serravallian Mid-Miocene Climatic Miocene Optimum (MMCO); 13.82 Onset of Mid-Miocene Neogene Langhian Cooling; expansion of 15.97 Antarctic Ice Cap Burdigalian 20.44 Aquitanian 23.03 0 4 8 12 16 20 % Extinctions Neogene Messinian Salinity Crisis Neogene Great American Biotic Interchange 40 mya (Bartonian) - 2.7 mya (Piacenzian) Neogene Sea-Level Changes System Series Stage Mya 2.58 Piacenzian 3.60 Pliocene Zanclean 5.33 Messinian 7.25 Tortonian 11.63 Miocene Serravallian 13.82 Neogene Langhian 15.97 Burdigalian 20.44 Aquitanian 23.03 0 4 8 12 16 20 % Extinctions Diagram from xxx et al. (xxx) Neogene Ocean Anoxia Events System Series Stage Mya 2.58 Piacenzian 3.60 Pliocene Zanclean 5.33 Messinian 7.25 Tortonian 11.63 None Miocene Serravallian 13.82 Neogene Langhian 15.97 Burdigalian 20.44 Aquitanian 23.03 0 4 8 12 16 20 % Extinctions Neogene LIP Eruptions System Series Stage Mya 2.58 Piacenzian 3.60 Pliocene Zanclean 5.33 Messinian 7.25 Tortonian 11.63 Miocene Serravallian 13.82 Neogene Langhian Columbia River (2.1 15.97 Kkm2) Burdigalian 20.44 Aquitanian 23.03 0 4 8 12 16 20 % Extinctions Paleogene LIP Eruptions Columbia Riven Igneous Province Age: c. 17 - 14 Mya (most intense interval) Extent: 2.1 Kkm2 Duration: 3 m.y. Location: Northwestern US Though volcanism has characterized this region for the past 20 m.y., most geologists accept that this LIP was emplaced when the North American plate moved