What Is Geobiology?

Geobiology spans the frontier between biology and geology. Although the two fields have independently matured, they must combine to better understand complex, remote and extreme environments.

The field’s emphasis is on understanding the myriad influences of geological processes on macro- and micro-scale patterns of biogeography. Examples include: the Archean era introduction of oxygen to Earth’s atmosphere by photosynthetic bacteria; and, the role of climate, soils, geology, altitude, topography, insularity, and disturbance in biotic diversity.

Origins

Although microorganisms have shaped the planet’s oceans and atmospheres for most of its history, it wasn’t until recently that geochemists and geologists fully appreciated the broad scope of their activity. Today, the study of geobiology offers significant payoffs for society.

Researchers in geobiology explore modern and ancient ecosystems including analogs of past environments. They use the rock record, and they collaborate with scientists in other fields, such as palaeontology and molecular biology.

An example of a geobiological question is the origin of oxygen in Earth’s atmosphere. Scientists are able to connect this major environmental change—known as the Great Oxygenation Event—to the evolution of photosynthetic cyanobacteria.

Another big question in geobiology is how organisms adapt to their environment. For instance, a geobiologist may look at the way a specific type of bacteria produces a protein that helps it to resist the glue-like biofilms that can cause infections such as cystic fibrosis. Such work reveals how adaptable life is and shows the value of studying the entire system.

Evolution

In geobiology, we explore how living systems shape and are shaped by their environment. The discipline enables us to address many of the grand questions that animate the science world, from Earth’s earliest environmental cradle to the controls on Neogene climatic change.

Geobiology brings together research from diverse fields, ranging from geochemistry and oceanography to microbiology, biogeophysics, and astrobiology. It’s a fertile crossroads for researchers from different disciplines to forge new collaborative partnerships that can produce fruitful work in the natural sciences.

For example, geobiologists are exploring the ability of bacteria to “breathe” metals like manganese and uranium, using them as terminal electron acceptors, just as humans use oxygen. The findings may open new avenues for environmental remediation.

Geobiology also addresses key basic science issues that affect society, such as global change and the search for life on other planetary bodies. The discipline is a growing field with tremendous potential for future advancements. However, geobiology and related disciplines must further develop their ability to work together.

Interactions

The interactions between different organisms and the lithosphere (rock) and atmosphere of Earth have been an important part of life's evolution through geologic time. Research in Geobiology spans a wide range of disciplines, including paleontology, geomicrobiology, astrobiology, biogeochemistry, mineralogy, microbiology and more.

For example, the oxygenation of the early Earth's atmosphere by photosynthetic bacteria was a major geobiological event that altered surface biogeochemical processes and led to the appearance of more complex eukaryotes. The formation of sedimentary structures such as banded iron formations resulted from biological activity, and microbial metabolisms have significantly altered the relative abundances of various mineral types in natural environments.

The broad scope of geobiological questions requires interdisciplinary research, especially across the boundaries between disciplines. Many of the researchers involved in geobiology are also active in related fields such as geochemistry, microbiology, planetary science, oceanography and astrobiology. These interdisciplinary links are particularly valuable for studying the co-evolution of Earth and life.