Emergence of Life

Go to Course: https://www.coursera.org/learn/emergence-of-life

Introduction

**Course Review: Emergence of Life** As we continue to explore the universe and our place within it, the study of life on Earth offers profound insights into our origins and the potential for existence beyond our planet. Coursera's course "Emergence of Life," offered by the University of Illinois Urbana-Champaign, serves not just as an academic inquiry into biological history but as an engaging narrative connecting ancient Earth to contemporary life and even our cosmic neighbors. ### Course Overview "Emergence of Life" invites participants to delve into one of the most captivating questions in science: how did life emerge on Earth, and how has it co-evolved with our planet over billions of years? Throughout the course, learners will evaluate the complex tapestry of biological evolution through the lens of the modern Tree of Life, utilizing groundbreaking research led by Professor Carl Woese that fundamentally transformed our understanding of genetic relationships among life forms. ### Curriculum Breakdown **Orientation** The course begins with an orientation module that familiarizes students with the structure of the course, the instructors, and fellow learners. This introduction sets the stage for collaborative learning and engagement. **Week 1 - Geological Time and the Nature of Science** This module explores the historical and philosophical underpinnings of scientific research. Discussions on the scale of geological time will prepare students for complex concepts that follow, highlighting the crucial interplay between Earth’s formation and the environmental conditions that facilitated the emergence of life. **Week 2 - The Tree of Life and Early Earth Environments** Participants will dive into molecular phylogeny and learn about the physical, chemical, and biological processes that contributed to the advent of life. This module serves as a fascinating introduction to the connections between our ancient planet and the universe. **Week 3 - Fossilization and Precambrian Life-Earth Interaction** This week’s focus on ancient fossils allows students to appreciate the detailed reconstructions of long-extinct organisms. Understanding these interactions between life and Earth provides insights into the evolutionary pathways that shape our biosphere today. **Week 4 - Paleozoic Life After the Advent of Skeletons** Through the lens of the Cambrian Explosion, learners will explore the evolutionary leap that occurred with the development of hard skeletons, allowing for greater diversity in life forms. Key concepts of radiation, diversification, and extinction will be pivotal in understanding these early ecosystems. **Week 5 - Paleozoic Plants, Reptiles, and the Transition to Land** This module examines the significant transition of life from aquatic to terrestrial environments, providing a comprehensive look at how plants and vertebrates adapted to land—a critical evolution in our planet's history. **Week 6 - Mesozoic Reign of the Dinosaurs and the Development of Flight** The dramatic rise and fall of the dinosaurs are captured in this module, alongside the exploration of symbiosis and ecological opportunities that arose post-extinction. This period's upheavals illustrate life’s resilience and adaptability. **Week 7 - Cenozoic Mammals and Global Environmental Change** The focus here shifts to the diversification of mammals following the dinosaurs' extinction, exploring how various environmental factors influenced evolutionary trajectories, including the emergence of primates. **Week 8 - Astrobiology and the Search for Life in the Cosmos** As the course concludes, learners will contemplate the broader implications of life on Earth. Engaging with the emerging field of astrobiology, students will analyze potential biospheres in the universe and the future of space exploration. ### Recommendations This course is ideal for anyone interested in biology, earth sciences, or astrobiology, as it skillfully integrates these disciplines into a coherent narrative about life’s evolution. Whether you’re a student, a science enthusiast, or a lifelong learner, "Emergence of Life" provides an enriching experience replete with scientific rigor and thought-provoking inquiries. With its insightful instruction, well-structured curriculum, and the profound questions it raises about our existence, I highly recommend "Emergence of Life" to all curious minds eager to explore the intricate story of life on Earth and beyond. Enroll, and embark on a journey through time that reveals not just the history of life but the very essence of our place in the universe.

Syllabus

Orientation

In this module, you will become familiar with the course, your instructor, your classmates, and our learning environment.

The week begins with a discussion of the historical and philosophical approaches that have been developed for the completion of scientific research, with the work of Professor Carl Woese evaluated as an example. The basic tools required for this type of scientific reasoning and the ability to overcome the challenging concepts of scale and complexity are then presented. Finally, we'll explore the dynamic formation of the Earth itself with respect to the environmental conditions present on the earliest and most ancient version of planet Earth.

The advent of life on Earth came about as a result of a remarkable confluence of physical, chemical, and biological processes, all of which were intrinsically linked to rapidly changing early Earth environments. Within this context, cutting-edge approaches in molecular phylogeny by Professor Carl Woese revealed new understandings of the emergence of life and the possible distribution of life within the cosmos. All this and more will be explored in this week's lessons!

This week, you'll explore how scientists interpret ancient fossilized life, which yields remarkably detailed and complete reconstructions of the lifestyles of ancient organisms that have been deceased for hundreds, thousands, millions, and even billions of years. These reconstructions provide valuable information regarding the evolutionary success of organism morphology and lifestyle.

This week, you'll learn more about the Cambrian Explosion, which led to the development of external hard skeleton components at 542 million years before present. The initial successes of the invertebrates were shortly followed by the appearance of vertebrates with internal skeletons. Life then utilized these newfound evolutionary capabilities, beginning distinct cycles of radiation, diversification, and extinction, which define the three great Eukarya faunas of the Phanerozoic.

In the early Paleozoic, plants evolved to leave the water and invade the terrestrial landscape. Following this transition, vertebrates emerged into land-based ecosystems, and Carbon Dioxide concentrations increased in the atmosphere. The greenhouse warming of the Earth propelled the success of both prevascular and vascular plants, as well as the related terrestrial radiation of the three lineages of the reptiles. This week, you'll also learn about the Permian-Triassic mass extinction and later environmental changes that opened the door to the rise of the diapsids.

This week, you'll learn more about the Permian-Triassic extinction event, which caused more than 80% of life to go extinct. This opened vast swaths of ecological opportunity for radiation and diversification of life during the Mesozoic. You'll learn about symbiosis, which was widely utilized during this period, as well as the fascinating lineage of diapsid reptiles that rose to replace the synapsid predators of the late Paleozoic. We'll also discuss the rise of the dinosaurs, as well as the catastrophic meteor impact that drove the dinosaurs to extinction.

With the demise of the dinosaurs, mammals rapidly radiated and diversified during the Cenozoic. The combination of abundant food sources and significant fluctuations in global climate fostered extreme variations in morphology, body size, and interaction with the environment. You'll learn why mammals had a distinct advantage over previous groups, and you'll also have the opportunity to explore multiple theories on primate and hominoid evolution in the context of global conditions during this period.

No matter where you are or what you believe, sometime in your life you will look up into the sky and ask: What is out there? Where are we going? Is there life elsewhere in the universe? This course is dedicated to searching for answers to these questions. The fundamental concepts of life and habitable environments, established upon the modern synthesis of the Tree of Life, will direct us in recognizing biospheres that might be quite different from our own. In the last week of this course, we will look in detail at what the future has in store for space exploration and the search for life in the cosmos.