Geobiology Course

Lesson 1 • Fundamental Biogeochemical Cycles

Carbon, nitrogen, sulfur, and phosphorus cycles are examined as geobiological drivers. Understanding these cycles is prerequisite for interpreting biosignatures and Earth history.

Lesson 2 • Deep Time and Geological Timescales

Introduces the geological time scale and methods for reading Earth's rock record. Students develop intuition for the vast temporal scales central to geobiology.

Lesson 3 • Defining Geobiology as a Discipline

Geobiology's scope, history, and relationship to adjacent sciences are mapped. This context anchors all later technical content within a unified scientific framework.

Lesson 1 • Biomineralisation by Microorganisms

Covers biologically induced and controlled mineral precipitation by microbes. These processes produce diagnostic textures preserved in the rock record.

Lesson 2 • Microbial Diversity and Metabolism

Surveys the metabolic strategies microbes use to harvest energy from inorganic and organic substrates. This diversity underpins microbial roles in geochemical cycling.

Lesson 3 • Microbial Weathering of Minerals

Microbial dissolution and transformation of silicate and sulfide minerals are examined. Students link microbial activity to soil formation and elemental release.

Lesson 4 • Microbial Mats and Biofilms

Structured microbial communities are analysed as geochemically active units. Their spatial organisation creates steep chemical gradients that drive mineral transformations.

Lesson 1 • Earliest Evidence of Life on Earth

The oldest putative biosignatures from Archaean rocks are critically evaluated. Students apply biosignature criteria from Chapter 3 to assess claims of early life.

Lesson 2 • Origin of Eukaryotes and Endosymbiosis

Endosymbiotic theory and the geobiological context of eukaryote emergence are examined. Students link cellular complexity to environmental and ecological transitions.

Lesson 3 • Great Oxidation Event and Its Consequences

The rise of atmospheric oxygen around 2.4 billion years ago transformed Earth's surface chemistry. Students analyse causes, timing, and biological and geological consequences.

Lesson 4 • Evolution of Photosynthesis

The development of anoxygenic and oxygenic photosynthesis is traced through the rock record. Students connect photosynthetic evolution to planetary-scale geochemical change.

Lesson 1 • Molecular Fossils and Biomarkers

Lipid biomarkers preserved in sedimentary rocks record the presence of specific biological groups. Students learn extraction, analysis, and interpretation of these molecular archives.

Lesson 2 • Types of Biosignatures

Morphological, chemical, and isotopic biosignatures are classified and compared. Recognising each type is essential for interpreting ancient life in the rock record.

Lesson 3 • Microfossils and Their Interpretation

Techniques for identifying and authenticating microfossils in cherts and carbonates are covered. Students apply criteria to distinguish genuine microfossils from pseudofossils.

Lesson 4 • Stable Isotope Geobiology

Carbon, sulfur, and nitrogen isotope systems are applied to reconstruct biological activity. Isotopic fractionation patterns serve as quantitative biosignatures in ancient rocks.

Lesson 1 • Ocean Chemistry Through Time

Redox state, salinity, and trace metal concentrations of ancient oceans are reconstructed. These records reveal how ocean chemistry co-evolved with life and atmosphere.

Lesson 2 • Integrating Proxies into Palaeoenvironmental Models

Multiple proxy datasets are combined to construct coherent palaeoenvironmental reconstructions. Students practise synthesising conflicting proxy signals into robust interpretations.

Lesson 3 • Atmospheric Proxies and Palaeoatmosphere

Methods for reconstructing ancient atmospheric oxygen and carbon dioxide levels are covered. Students connect atmospheric reconstructions to biological and climatic events.

Lesson 4 • Principles of Proxy Reconstruction

The logic of using chemical and physical signals in rocks as environmental proxies is established. Students learn to assess proxy fidelity, diagenetic alteration, and uncertainty.

Lesson 1 • Patterns and Causes of Mass Extinctions

The five major mass extinctions are analysed for their geobiological signatures and causes. Students identify common environmental stressors and biological vulnerabilities.

Lesson 2 • Recovery and Radiation After Extinction

Post-extinction recovery dynamics and evolutionary radiations are examined across multiple events. Students analyse how survivors reshape ecosystems and drive new geobiological cycles.

Lesson 3 • Cambrian Explosion and Animal Origins

The rapid diversification of animal body plans in the Cambrian is examined through fossil and geochemical evidence. Students evaluate environmental triggers and ecological drivers.

Lesson 4 • Neoproterozoic Snowball Earth Events

Global glaciation events and their biological consequences are analysed using sedimentary and isotopic evidence. Students connect extreme climate perturbations to evolutionary transitions.

Lesson 1 • Soil Geobiology and Critical Zone Science

The critical zone from bedrock to canopy is analysed as an integrated geobiological system. Students examine how organisms drive weathering, nutrient cycling, and soil development.

Lesson 2 • Wetlands, Peatlands, and Carbon Storage

Organic carbon accumulation in wetland and peatland systems is examined as a geobiological process. Students link microbial decomposition rates to long-term carbon burial.

Lesson 3 • Hydrothermal Vent Ecosystems

Chemosynthetic communities at mid-ocean ridges are examined as models of early Earth ecosystems. Students analyse energy flow, mineral precipitation, and community structure.

Lesson 4 • Carbonate Systems and Reef Geobiology

Biological carbonate production in reefs and shallow marine settings is analysed. Students connect organism-scale calcification to basin-scale carbonate accumulation.

Lesson 1 • Ocean Worlds and Icy Moon Habitability

Subsurface oceans on Europa, Enceladus, and similar bodies are evaluated as potential habitats. Students connect deep-sea geobiology to extraterrestrial ocean environments.

Lesson 2 • Mars as a Geobiological Target

Mars's geological and geochemical history is evaluated for past and present habitability. Students apply geobiological proxy methods to interpret Mars mission data.

Lesson 3 • Habitability: Concepts and Requirements

The physical and chemical requirements for life as we know it are defined and evaluated. Students apply habitability criteria to assess environments on Earth and other worlds.

Lesson 4 • Panspermia and Life's Cosmic Context

Hypotheses for interplanetary transfer of life are evaluated against geobiological and physical evidence. Students place Earth's biosphere within a broader cosmic perspective.