E412/G512 Vertebrate Paleontology
Vertebrate paleontology is the study of the deep-time history and environmental context of vertebrate evolution. To understand the history of vertebrate diversification in the context of changing Earth systems is the aim of this course. The course will develop critical skills for interpreting the vertebrate fossil record, including morphology, stratigraphy, and biogeography and for analyzing it using phylogeny, biomechanics, and synthesis of scientific research papers.
1. Overview of vertebrate paleontology
This lecture presents a broad overview of vertebrate diversity past and present. Basic concepts are introduced of phylogeny and "heritage" and "habitus", the mixture of ancestral characteristics and specializations that define an animal's way of life.
Lecture 1 - Introductions.pdf2. Overview of Earth history
This lecture will give you a broad overview of Earth history during the Phanerozoic (the last 541 million years), the period relevant for vertebrate evolution. We will discuss continents, climates, major extinction events, and sea level.
Lecture 2 - Overview of vertebrate evolution.pdf3. Vertebrate body plan
What is a vertebrate and how is it put together? This lecture gives you an overview of the anatomical organization at a level that is common to all vertebrates. We will contrast it with the body plans of other animal groups.
Lecture 4 - Vertebrate body plan.pdf4. Structure of the skull
This lecture is about details of the skull, including its bones, its openings (foramina and canals), and the soft tissue anatomy associated with them. The goal is to be able to look at a skull and decipher the living animal to whom it once belonged.
Lecture 5 - The skull.pdf5. Diversity of the skull
This lecture focuses on how the structure of the skull differs among major vertebrate groups, how that variety is associated with their functional differences, and on the concept of homology.
Lecture 6 - Skull diversity.pdf6. Structure of the skeleton
This lecture introduces you to the so-called “post-cranial” skeleton, or the all rest of the skeleton that sits behind the skull. We will learn the bones and think about the muscles associated with them.
Lecture 7 - The skeleton.pdf7. Diversity of the skeleton
This lecture compares the skeleton in different vertebrate groups, emphasizing that mammals have much simpler skeletons than most. We will consider how the skeleton is related to the locomotion and ecology of the animal to which it belongs
Lecture 8 - Diversity of skeleton.pdf8. Functional morphology
This lecture introduces you to the inference of function from form, including basic anatomical interpretation, biomechanical ratios, and computerized techniques like finite element analysis (FEA).
Lecture 9 - Functional morphology.pdf9. Limb Ecomorphology
This lecture introduces you to functional morphology of limbs, including lever systems and joint mobility, as well as to the range of limb specializations that are associated with climbing, running, jumping, swimming, and othe types of locomotion.
Lecture 10 - Limb ecomorphology.pdf10. Jaws, teeth, and diet
This lecture introduces you to vertebrate diets, their caloric and physiological properties, and the range of specializations in jaw, tooth, and masticatory structures that are associated with different kinds of chewing.
Lecture 11 - Jaws, teeth, and diet.pdf11. Dissecting Paleontology Papers
This lecture introduces you to scientific literature in paleontology, including types of publications (reviews, original research, descriptive research), how to locate them (especially older literature that remains highly relevant beause of its descriptive or taxonomic content), and how to parse the taxonomic information presented in descriptive papers.
Lecture 12 - Dissecting paleontology papers.pdf12. The mammalian radiation
This lecture is the first in a series that introduce you to vertebrate diversity and evolution, starting with mammals. Here we discuss the origin of mammals in the Triassic and their antecedants in the Paleozoic and the evolution of their unique middle ear and complex occlusion-based mastication system. We also discuss models of mammalian evolution (short-fuse and long-fuse) and compare and contrast the strengths and weaknesses of the fossil record and molecular clock inferences for studying the timing of evolutionary diversification. This video complements this lecture.
Lecture 13 - Mammals.pdf13. Cenozoic climates and biomes
In this lecture we will learn about the remarkable climatic and environmental changes that have unfolded over the last 65 million years since the extinction of dinosaurs. At the start of the Cenozoic the Earth's climate was much hotter than today and tropical and subtropical forests covered nearly the entire globe, including within the Arctic Circle. As the continents were repositioned, ocean currents redirected, and atmospheric composition altered, global climate cooled in a series of steps ultimately leading to the glacial-interglacial cycles of the last 2 million years. New biomes arose as the climate changed, including grasslands, deserts, and tundra.
Lecture 14 - Cenozoic climates and biomes.pdf14. Bone histology, geochemistry, and ancient biology
Many environmental and physiological parameters from the deep past can be inferred from fossilized bone. These include inferences about the growth physiology of the animal itself and the parameters of the environments it inhabited. In this lecture we will learn about the mineral and organic composition of bone, its structure, and geochemical techniques for extracting information from it.
Lecture 15 - bone histology, geochemistry, and ancient biology.pdf15. The Paleozoic diversification of fishes
The ancestral vertebrate was a "fish" and the vertebrate body plan was established in a marine environment. In this lecture we learn about the first vertebrates and their diversification into a wide range of "jawless" fish groups during the Paleozoic Era. We will also learn about geometric morphometrics and phylogenetic analysis in the context of the diversification of osteostracan fish.
Lecture 16 - the evolution of fish.pdf16. Gnathostomes
In the mid-Paleozoic one fish group - the gnatostomes - evolved jaws. In this lecture we look at the diversity of jawed fishes, including bizarre early cartilagineous fishes with unusual electrosensory organs, as well as placoderms and ray-finned fishes.
Lecture 17 - Fish Two, the gnathostomes.pdf17. Tetrapods and the conquest of land
The phrase "conquest of land" is completely clichéd, yet it is a appropriate because the evolution of the first land vertebrates was a complex affair that involved changes in locomotion, breathing, feeding, and sensory systems. In this lecture we look at this key transition in its mid-Paleozoic context of changing oceans, continents, and climate.
Lecture 18 - Tetrapods.pdf18. Late Paleozoic tetrapods
In the Late Paleozoic terrestrial ecosystems grew to be complex, with vertebrate groups dominated by large amphibians and the synapsid ancestors of mammals who inhabited a world of flowerless forests and swamps that they shared with carnivorous insects. Interactions between the atmosphere and the diversifying land plant community and the coalescence of land masses into the super-continent Pangea led to a series of climatic events that changed the course of vertebrate evolution, resulted in the evolution of amniotes, and eventually produces the world's biggest mass extinction when 95% of species perished.
Lecture 19 - late Paleozoic tetrapods.pdf19. The End Permian Extinction
At the end of the Paleozoic plate tectonic events, runaway greenhouse, and changing climate resulted in the biggest mass extinction the Earth has yet experienced. 95% of species became extinct in a crisis that changed the course of life on Earth.
Lecture 20 - the Permian-Triassic extinctoin.pdf20. The Triassic
The Mesozoic era opened with the Triassic 251 million years ago. Life and ecosystems were rebuilding in a radically altered geographic and climatic setting following the end-Permian extinction. Vertebrate communities were no longer dominated by the synapsid relatives of mammals and were instead rebuilt with dominant roles filled by new reptile groups, including dinosaurs, but also including truly bizarre groups like tutles, icthyosaurs, plesiosaurs, pariesaurs, and others.
Lecture 21 - The Triassic.pdf21. The Jurassic and Cretaceous
The "Age of Dinosaurs" filled the remainder of the Mesozoic, a period of extremely warm and wet climates on average. The asteroid-driven mass extinction at the very end of the Cretaceous often captures attention, but the demise of Mesozoic ecosystems and the origin of the Cenozoic world we currently inhabit was arguably more the results of the "Cretaceous Terrestrial Revolution" in which flowering plants evolved and diversified, and with which polinating insects, fruit and nut eating vertebrates, snakes and lizards, and birds and mammals coevolved.
Lecture 22 - Jurassic and Cretaceous.pdf22. Careers, professional societies, and ethics
In this session we will look at the profession of paleontology. We will talk about careers (and introduce three guests who will visit us virtually over the coming weeks), professional societies (including conferences, science advocacy, and scientific ethics), and look at laws, regulations, and ethical standards associated with collecting, storing, and researching fossil vertebrates.
Lecture 23 - Professional societies and careers.pdf23. Public land and paleontology
Because vertebrate paleontology ultimately relies on fossils collected from the rocks at the surface of the Earth, this scientific discipline is closely tied to public land (on which scientists can usually obtain permission for field-based research) and the regulations and politics that intersect with public land management. We will learn about public land, laws affecting it, legal and illegal commercial trade in fossils, and political controversies about the purpose of public land, as well as about the role of research repositories in meeting scientific and regulatory goals.
Lecture 24 - Public lands and paleontology.pdf24. Integration I: the evolution of body mass
Many, many dietary, ecological, and evolutionary aspects of animals are influenced by how big they are. In this lecture and its associated exercises we will learn why body size affects metabolism and as a consequence diet and locomotion. We will then examine the history of vertebrate body size, diet, and locomotion in the context of changing Earth climates and environments.
Lecture 25 - Evolution of body mass.pdf25. Integration II: What is evolution?
In this session we will learn about the mechanisms of evolution: how does it work, why does it work, what are its consequences? We will look at this history of how the scientific understanding of evolution grew, what alternative explanations once seemed viable, and the reasons why they were discarded. Surprisingly, the deepest scientific controversies were more about the concept of extinction than evolution because the idea of evolution is a logical consequence of the existence of extinction. We will learn about current understanding of how genetics, development, and plasticity underpin morphological evolution and adaptation.
Lecture 26 - What is evolution?.pdf