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The TIME Lab (Tracing Impacts of Mass Extinctions) investigates the profound effects of mass extinction events on life's history through the study of fossil records, bone histology, and evolutionary patterns. By analysing ancient bones at the microscopic level and exploring how ecosystems responded to past crises, the lab uncovers the dynamics of survival, adaptation, and biodiversity loss. This cutting-edge research deepens our understanding of life's resilience and provides insights relevant to modern conservation challenges.

The vision of the lab is to advance our understanding of mass extinction events as transformative junctures in Earth's history, using South Africa's unparalleled geological and fossil record to reveal the causes, consequences, and recovery mechanisms of life during these critical periods. By drawing connections between historical extinctions and current biodiversity crises, this research seeks to inform and guide global strategies for conservation, ecosystem resilience, and sustainable coexistence in the face of ongoing and future environmental challenges.

The Chop Shop

At the Evolutionary Studies Institute, I have a fully equipped, state-of-the-art osteohistology laboratory—fondly referred to by my students as the "Chop Shop." Here, we analyze growth patterns of both modern and extinct vertebrates by cutting tiny bone samples into thin sections. We work with a range of specimens, from meerkats to dinosaurs. The unique advantage of osteohistology is its versatility; it allows us to study any vertebrate from any time period. These thin sections offer an unparalleled glimpse into the lives of extinct animals, beyond what traditional methods can achieve.

Here's how we do it -

1. Vacuum Chamber Embedding

Fragile fossil and modern bone specimens are first embedded in Struers Epofix resin within a vacuum chamber. This step ensures the structural integrity of the bones, preventing breakage during subsequent processing. (Shown in the first and second images)

2. Cutting and Grinding with the Struers Accutom-100

The Struers Accutom-100 is used to cut the embedded bones into precise sections, starting at a thickness of 2mm. These sections are then adhered to frosted glass slides and further ground down to an ultra-thin 60 microns using the same machine, preparing them for microscopic examination. (Shown in the third image).

3. Microscopic Imaging

The prepared slides are analyzed using a Nikon Eclipse Ci POL polarizing microscope equipped with a DS-Fi3 digital camera and NIS-Elements 4.6 software. Images are captured under normal, polarized, and cross-polarized light, allowing for detailed examination of bone histology and microstructure.

The Chop Shop

— State of the Art Equipment —

Struers Accutom-100

Vacuum Chamber

Nikon Polarizing Microscope

European Synchrotron Research Facility

The European Synchrotron Research Facility in France has recently developed virtual thin-sectioning techniques, with resolution improving annually. Although not as detailed as physical thin sections, I am becoming increasingly involved in synchrotron-based osteohistology as it allows us to obtain information when a fossil cannot be physically thin sectioned. Additionally, I have assembled several hundred modern reptiles, birds, and mammals as part of an ongoing project to build a comprehensive comparative database for understanding life histories of extinct vertebrates.

My Research

My research focuses on understanding how vertebrates respond to catastrophic environmental changes, with a particular interest in mass extinction events. I study the Permo-Triassic and End-Triassic extinctions to uncover patterns of survival and recovery, using techniques like osteohistology to examine fossil bone microstructure. This allows me to explore growth, life history, and ecological adaptations in both ancient and modern vertebrates. I also have a deep interest in therapsids, the mammalian ancestors that dominated terrestrial ecosystems before the rise of dinosaurs, and my work bridges the past and present to shed light on biodiversity and environmental resilience.