ECR Spotlight is a series of interviews with early-career authors from a selection of papers published in Journal of Experimental Biology and aims to promote not only the diversity of early-career researchers (ECRs) working in experimental biology but also the huge variety of animals and physiological systems that are essential for the ‘comparative’ approach. Harriet Goodrich is an author on ‘ Specific dynamic action as the energy cost of digestion or growth?’, published in JEB. Harriet is a lecturer in aquaculture production and aquatic animal physiology at the University of Tasmania, Australia, investigating how integrative, comparative and eco-physiology can be used as a tool to address global challenges in aquaculture production, fisheries management and conservation.

Harriet Goodrich

How did you become interested in biology?

Like many biologists, my interest in biology began with a nature-rich childhood. Growing up on our family farm in the UK, I spent much of my time outdoors – fishing, horse riding and swimming. I vividly recall the excitement of catching my first (tiny) fish after school in the stream that ran through the farm, when I was 5–6 years old. When my family moved to Queensland, Australia, in the early 2000s, my brain exploded at the sheer contrast of this new landscape. The backyard of our new home was filled with giant Eucalyptus, venomous spiders, fluorescent insects, rainbow lorikeets, noisy galahs, wallabies and even a koala. Regular trips to Mulgumpin and K'gari revealed marine wonders from bright fish and turtles to rays, dolphins, whales and coral – experiences unlike anything I’d had in the UK. From then, you couldn't pull me out of the water, and most of my weekends were spent in the ocean. How could I not want to spend my life in biology with these incredible surroundings and experiences as my inspiration? Reflecting on my childhood, I acknowledge the privilege of these formative experiences, shaping my personal life and laying the foundation for a meaningful career in biology.

Describe your scientific journey and your current research focus

I spent my first few years at university failing miserably at every subject under the sun. It was a ‘last chance’ email that prompted me to enrol in a Bachelor of Science at the University of Queensland, Australia, majoring in zoology and marine science. Turns out studying something you're interested in can drastically improve your academic performance! I spent the last part of my undergraduate studying biochemistry at the University of Bath, UK, then came back to the University of Queensland to start an honours year with Prof. Craig Franklin. I’d volunteered for Craig’s lab throughout my undergrad and assisted on a bunch of projects with frogs, crocodiles and fish. It was these opportunities that cemented my desire to work in animal physiology. Luckily for me, Craig overlooked my horrid early academic transcript and took me on board. During my honours, I worked on fish passage within the Murray Darling basin and fell in love with Australia's freshwater environments. Post-honours, I remained as a Research Assistant, contributing to novel remediation strategies for native fish passage. While I enjoyed research in conservation physiology, I knew I wanted to apply my skills to research in aquaculture. So, with some encouragement, I applied for a dream aquaculture PhD with Prof. Rod Wilson and, surprisingly, I was offered a competitive scholarship to study at the University of Exeter, UK. Moving labs and working with Rod’s group was transformative to my development as a research scientist. Here, my work focused on acid–base responses to feeding, metabolism, fish growth and novel feed ingredients. Thanks to Rod, I had abundant opportunities and experiences during my PhD, including a graduate course in the Mekong River delta, in Vietnam, where I met Prof. Chris Wood. We formed a humorous rivalry while studying the gastrointestinal physiology of air-breathing fish, and I brought these newfound skills back to Australia to work on barramundi feeds with Prof. Andy Barnes and Ridley Aquafeeds. Here, I was attempting to reduce the specific dynamic action (SDA) through dietary acidification for carry-over effects on growth. But it didn't all go to plan, and some background for the Commentary we've just published in JEB was born. Now based at the Institute for Marine and Antarctic Studies in lutruwita (Tasmania), I'm working as a lecturer in sustainable aquaculture and aquatic animal physiology. Here, my research focuses on the application of physiology to aquaculture performance, fisheries and conservation. Current projects include mitigating the impacts of summer warming in Atlantic salmon aquaculture, understanding the effect of recreational fishing on the physiological performance of southern sand flathead and investigating the digestive physiology of the endangered Maugean skate.

Field work is arguably the best bit about research. This was off lunawanna-allonah (Bruny Island) fishing for squid (I'm clearly excited about it!).

Field work is arguably the best bit about research. This was off lunawanna-allonah (Bruny Island) fishing for squid (I'm clearly excited about it!).

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

The metabolic response to feeding, commonly known as the specific dynamic action (SDA) has been studied for centuries. But what this response truly represents remains a subject of debate within the literature. The most widely accepted view considers SDA as an energy ‘tax’ on food processing; hence, the use of the term ‘energy cost of digestion’. This perspective suggests that a reduction in the SDA for the same caloric intake should provide animals with more ‘free’ energy to allocate to somatic growth. Yet, support for this hypothesis remains scarce and inconclusive. The opposing view proposes the exact opposite, that majority of the SDA represents the energy cost of protein synthesis and growth, and that a larger SDA for the same caloric intake will be associated with enhanced growth. In this Commentary, we present evidence both for and against these perspectives and provide future research questions aimed at determining the true nature of the SDA. Our hope is that the insights shared in this Commentary will stimulate further work and discussion on the relationships between SDA and growth.

What do you enjoy most about research, and why?

Freedom, answering complex questions, feeling challenged and working with students in physiology and aquaculture. A career in academia has given me the opportunity to focus on the research questions I want to ask, to address global challenges, and to create experiences that enrich the learning of students. If we are talking about day-to-day highlights, nothing beats witnessing my students’ ‘aha’ moments as they grasp complex concepts in the lab, generate their first dataset, ask a great question, or find inspiration in physiology. And, of course, doing all of this in one of the most beautiful places in the world has its perks too.

Do you have a top tip for others just starting out at your career stage?

Asking interesting research questions will always lead to interesting research outcomes, regardless of the results. Build a supportive network of like-minded, kind, knowledgeable colleagues who are genuinely invested in your career. Stop putting off learning how to code and use R.

Harriet Goodrich’s contact details: Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, TAS 7001, Australia.


H. R.
C. M.
R. W.
T. D.
K. B.
Specific dynamic action as the energy cost of digestion or growth?
J. Exp. Biol.