Organisms have gravity: taking an organism-centered approach in experimental biology

When thinking about a research topic in biology, the number of fields, concepts, systems and unanswered questions can be daunting, to say the least. What should I study? What should I propose for my thesis? What should my lab focus on? These are common questions that can feel overwhelming at any career stage, but especially when first starting out.

A couple of approaches to setting a research direction are often discussed among the scientific community. One is dedicated to the pursuit of particular questions and seeks to find the organisms most suitable for research to answer those questions. The other develops from a fascination with a particular organism or lineage, leading to a desire to understand it, thus letting one's knowledge of the organism lead to important questions about their biology. Although these two approaches are not mutually exclusive and do not represent all possible approaches to organismal biology, this oft-perceived dichotomy is nicely encapsulated by advice given to an evolutionary biologist, Dr Bree Rosenblum, at the start of her PhD. When she separately asked two mentors what she should focus on for her thesis, she received two different pieces of advice. One said, ‘Think about a big question you want to answer and find the perfect system to test it’, and the other said, ‘Fall in love with your organism and let the questions pour out’.

Neither mentor was wrong, right, better or worse, but in this Perspective, we want to highlight the latter point of view because we believe it is too often undervalued or considered more romantic than scientifically rigorous. Many organismal biology courses and papers highlight Krogh's principle, which posits that there are ‘animals of choice’ in which to most conveniently study many biological questions (Krogh, 1929). But often, people don't choose the organisms they study for purely intellectual reasons. Instead, their captivation with a particular study organism results either from happenstance encounters in early life or after involvement with research on a particular organism. What is clear is that once you start paying attention to any organism, curiosity and connection are almost inevitable (Ding et al., 2024).

When we dedicate ourselves to observing an organism, they exert a metaphorical gravity that pulls us closer. This gravity inspires a mixture of curiosity and a sense of connection among organisms that expands and strengthens with more interaction. Although not a prerequisite for research, a connection with your study organism is common, and we believe that it is as valuable as any theoretical approach or analytical technique.

Experiencing the ‘gravitational pull’ of a particular species can lead researchers to conduct integrative work. Observing the organism – how it moves (or doesn't), where it goes and what it does – raises questions about function and mechanism, which lead to further examination of its outward proportions and internal structures and processes (i.e. morphology, biomechanics and physiology). Knowledge of how organisms find refuge, feed, breathe and reproduce results in new questions about their interactions with their environments (i.e. ecology or behavior). Experimentation and observation across multiple individuals and populations causes one to wonder how these aspects of the focal species are similar to and different from those of other members of the lineage (i.e. comparative biology). Questions about pattern and process of evolution of the lineage emerge, and data from studies of molecules and morphology provide estimates of divergence dates and relationships among organisms. A parallel examination of the developmental biology of the focal species compared with its relatives provides more information about how divergence in the lineage has occurred (i.e. evolutionary biology). Collectively, such studies provide not only a better understanding about the biology of the species, but also new insights across multiple fields, transforming organismal biology into an essential, synthetic and potentially predictive part of biology. Often, the careful observation and deep understanding of an organism supplies the best available question, whereas a scientist's fascination and connection with that organism propels the research into deeper biological inquiry.

Organism-centered biology reveals other ways of being in the world and even other worlds, entirely: organisms persist at vastly smaller and larger size and time scales than the researcher and with differing dominant sensory and cognitive processes. Even within our own species, viewing the world through another individual's perspective is incredibly difficult, making empathy seem impossible among species that lack shared language. Yet, attempting to understand the vantage point of other organisms, however limited and flawed, can spark ideas and discoveries that one would never reach by keeping an intellectual distance.

Too often, the pull that some scientists experience towards a particular organism is acknowledged in a negative light, which can be especially impactful for early-career scientists who are inspired to pursue research precisely because of that pull rather than a depth of knowledge of the field. Emotional connections between researchers and their study subjects are sometimes explicitly or culturally discouraged (Byrne, 2023). Additionally, students are sometimes warned not to focus ‘too much’ on their organism at the risk of becoming strictly ‘organism-centered’, as if this were harmful to their scientific advancement. The past 30 years have shown the opposite to be true, as a renaissance in integrative, organism-centered biology has led to deeply conceptual and wide-reaching breakthroughs across the life sciences. Countless examples exist, including revelatory insights into the developmental processes underlying homoplasy from studies on salamander ‘wrist’ bones and feet (Wake, 1991), development of revolutionary technologies from the documentation of understudied bacterial species (Brock, 1997), increased appreciation of adaptive radiations borne out of studies of Anolis lizards (Losos et al., 1998) and a new understanding of different cell–cell signaling approaches from squid bioluminescence studies (Bassler, 1999). Natural history observations are often recognized as an important foundation for research, but are rarely prioritized in contemporary academia's culture of cutting-edge, publish-or-perish study designs. This can create a negative feedback loop where early-career scientists feel pressured to pursue uninspired research, leading to eventual disillusionment and disconnection.

Although an organism's gravity pulls us in and can lead to scientific advances, their gravitas – their seriousness, their contribution to the greater ecosystem, and the weighty entanglement of our shared ancestry – can inspire a drive to protect and conserve them in a changing world (Fig. 1). As an example, a person in California, noticing fewer frogs in their swimming pool, decided to contact a local amphibian curator and researcher, Dr David Wake. This observation, and the decision to contact someone with a passion for amphibian biology, sparked decades of research on amphibian decline and conservation efforts in the Wake lab, along with many other labs in locations across the globe. Thus, connecting with an organism can inspire people to invest in their persistence. Paired with the natural enthusiasm that comes from a researcher who is truly excited by their study animal, this can guide entire research programs and influence conservation policies (Mendelson et al., 2006).

Encounters and connections between humans and non-human organisms can not only fuel our personal interests and biological discovery as scientists, but also be effective tools for broadening who has access to science and who has a connection with the natural world. An organism-centered approach encourages observation over time by people familiar with the local conditions. This qualitative approach complements mechanistic work – it can lead to the generation of novel and interesting hypotheses to be tested experimentally and inform the design of biologically relevant experiments. Although often devalued in modern western science, this approach has been prioritized in traditional ecological knowledge and expands who is viewed as legitimately holding knowledge (Berkes, 1977; Huntington et al., 2004; Kimmerer, 2002). Viewing observational approaches as an essential component of scientific knowledge, along with quantitative and mechanistic methods, provides a more holistic outlook. An emphasis on observational knowledge (often termed ‘natural history’), can lead to the development of organism-focused databases, such as AmphibiaWeb (https://amphibiaweb.org), The Reptile Database (www.reptile-database.org), SquamataBase (Grundler, 2020), MammalBase (www.mammalbase.net), FishBase (www.fishbase.org) and eBird (Sullivan et al., 2009), which aggregate knowledge from different sources and approaches and communicate that knowledge to broad audiences. An organism-centered lens provides one of the most successful science communication tools, because we think of ourselves in relation to other organisms more than we think of ourselves in relation to other hierarchical levels of biology (e.g. molecular, cellular, ecosystem).

As we continue to change our planet in ways that affect nearly all other organisms, we should not fall into the trap of a false dichotomy between the two approaches of centering organisms versus centering questions. Instead, we encourage scientists at all career stages to consider how these complementary approaches can expand their research. The history of biological research is filled with unexpected discoveries from all sorts of approaches, but with one commonality – someone following their curiosity. All good research stems from curiosity, but what attracts a person's curiosity varies. Thus, it is incredibly important that people with different approaches, perspectives and passions are hired (at all levels), supported (with funding) and feel valued in the field of organismal biology. Although each decade brings revolutionary insights into the complexity of the natural world, there remains always more to be understood. With this in mind, it is essential to value ‘basic’ scientific research driven by organismal love as much as we value novel methods based on advanced theory. Making sure our field is not excluding particular perspectives and approaches is vital to tackling the bigger questions and challenges in biology.

We believe that research centering organisms has held and continues to hold an important role not only in scientific discovery, but also in the communication and perception of science. New methods, technologies and communication avenues make now an incredibly exciting time to be an organismal biologist. But, our excitement at the novel opportunities to study organisms should not overshadow the responsibilities we hold to the species we study, which have never been greater. With high and accelerating extinction rates predicted over the next 25–30 years (Thomas et al., 2004; Urban, 2015), we are running out of time to acknowledge and know many species. Our lack of understanding of other organisms – paired with the magnitude of the challenges faced by the natural world now and in the near future – can feel paralyzing. However, perhaps this is all the more reason to give in to the gravitational pull of other organisms and to value the connections and knowledge we gain in the process.

This Perspective was inspired by a special session at the 2023 Society of Integrative and Comparative Biology Meeting titled ‘What Amphibians Have Taught Us About Organism-Focused Evolutionary Biology’ that was held in honor of the late David B. Wake. M.C.W. would like to thank the special session organizers, David Blackburn and M.H.W., for their invitation to participate in that meaningful session. All authors would additionally like to thank their mentors, collaborators and lab mates through the years that expanded their views on empathy, connection and the importance of knowing their organism.