ECR Spotlight – Kristoffer Wild

Kristoffer Wild

How did you become interested in biology?

I was really fortunate to have great science teachers during grade school. Also as a kid, I spent much of my free time flipping rocks and pestering my parents about questions relating to the animals I brought into our house. So I guess I was interested in biology young but didn't truly realize it until I took a field zoology course during my undergrad. After this class, I quickly changed my major from history to biology! Since then, I haven't turned back.

Describe your scientific journey and your current research focus

I went to school to study environmental science in North Carolina. Here, I was lucky and was involved in starting a field project investigating the risks and responses of eastern box turtles to prescribed fire. I developed an interest in studying how natural fire regimes create thermal changes that affect reptiles, exploring both the short-term and long-term impacts of these disturbances. I followed these questions and pursued a master's degree, where I investigated the physiological responses of eastern fence lizard populations with different fire histories. Combining my interests in movement and physiological ecology, I moved to Australia to study the ecological and evolutionary significance of sex-reversal in Australian lizards. During this project, I was able to investigate how developmental environments influenced a suite of life history traits and test if phenotypic or genetic factors drove these traits. For my postdoctoral research, I continued this theme of linking developmental environments to physiological traits by applying experimental and meta-analytic approaches to investigate how developmental environments influence thermal physiological traits in reptiles. Currently, I'm utilizing mechanistic niche models to identify functional traits to understand how organisms will respond to climate change. Overall, the general theme of my research is to apply statistical modelling, molecular approaches and physiological traits from populations to understand how animals have and will interact with their environments.

How would you explain the main findings of your paper to a member of the public?

Our study looked at how the conditions lizards experience as eggs affect their growth and health throughout their life. We focused on two main factors: the temperature of their incubation and exposure to a stress hormone called corticosterone. As the climate warms, lizard eggs will be exposed to higher temperatures, and stress hormones from the mother might also affect their development. We wanted to see if these two factors combined would have a bigger impact, but we found they each acted independently. Lizards incubated at warmer temperatures hatched sooner and were smaller at birth, although they eventually reached normal adult sizes. Those exposed to higher levels of corticosterone also hatched smaller, and this effect continued into adulthood. Interestingly, lizards incubated at cooler temperatures had more efficient energy use as adults, suggesting that early-life temperature can shape how their bodies function long term. Our research shows that the environment lizards experience before hatching can have lasting effects on their growth and health. This insight helps us understand how reptiles might cope with changing climates.

Why did you choose JEB to publish your paper?

I chose JEB for this paper because the journal is widely read by researchers across various fields that our work touches on – endocrinology, physiology and demography. JEB has a reputation for publishing studies that deepen our understanding of animal biology in innovative ways, making it an ideal platform for our findings. I believe our research will resonate with JEB's readership by sparking new questions about how endocrine pathways shape development under different environmental conditions. I hope this work deepens the conversation on how endocrine mechanisms can drive alternative developmental pathways in response to environmental change and how this can affect subsequent generations.

What is your favourite animal, and why?

My favorite animal is Liolaemus poecilochromus, a small herbivorous lizard found in the cold, high-altitude regions of South America. Belonging to the Liolaemidae family, which is known for breaking the norms with multiple herbivorous species, L. poecilochromus is especially unique. Typically, plant-eating lizards are large and live in warm, tropical climates, where the heat aids in digesting their nutrient-poor diet. But these little lizards in this family defy these expectations – they thrive on plants despite their small size and the cold environment. Liolaemus poecilochromus and its relatives challenge what we know about reptile biology and evolution, making it a truly fascinating species and a rule breaker!

What's next for you?

I've started a postdoctoral position in the Climate and Metabolic Ecology Lab (CAMEL) with Mike Kearney at the University of Melbourne. I'm currently working on planning and compiling a functional trait database that will be used to develop mechanistic niche models. Our goal is to create a database template that can calculate the heat budgets for a range of animals, both endothermic and ectothermic. One area I'm excited to explore is how well these models can leverage historical datasets to predict real-world observations in dynamic environments, like those experiencing warming, drought and fire, to better understand species’ resilience in changing climates.