Ecologists often rely on observational data to understand causal relationships. Although observational causal inference methodologies exist, predictive techniques such as model selection based on information criterion (e.g. AIC) remains a common approach used to understand ecological relationships. However, predictive approaches are not appropriate for drawing causal conclusions. Here, we highlight the distinction between predictive and causal inference and show how predictive techniques can lead to biased causal estimates. Instead, we encourage ecologists to valid causal inference methods such as the backdoor criterion, a graphical rule that can be used to determine causal relationships across observational studies.

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Ecologists are often interested in answering causal questions from observational data but generally lack the training to appropriately infer causation. When applying statistical analysis (e.g., generalized linear model) on observational data, common statistical adjustments can often lead to biased estimates between variables of interest due to processes such as confounding, overcontrol, and collider bias. To overcome these limitations, we present an overview of structural causal modeling (SCM), an emerging causal inference framework that can be used to determine cause‐and‐effect relationships from observational data. The SCM framework uses directed acyclic graphs (DAGs) to visualize researchers' assumptions about the causal structure of a system or process under study. Following this, a DAG‐based graphical rule known as the backdoor criterion can be applied to determine statistical adjustments (or lack thereof) required to determine causal relationships from observational data. In the presence of unobserved confounding variables, an additional rule called the frontdoor criterion can be employed to determine causal effects. Here, we use simulated ecological examples to review how the backdoor and frontdoor criteria can return accurate causal estimates between variables of interest, as well as how biases can arise when these criteria are not used. We further provide an overview of studies that have applied the SCM framework in ecology. SCM, along with its application of DAGs, has been widely used in other disciplines to make valid causal inferences from observational data. Their use in ecology holds tremendous potential for quantifying causal relationships and investigating a range of ecological questions without randomized experiments.

Recent developments in computer science have substantially advanced the use of observational causal inference under Pearl's structural causal model (SCM) framework. A key tool in the application of SCM is the use of casual diagrams, used to visualize the causal structure of a system or process under study. Here, we show how causal diagrams can be extended to ensure proper study design under quasi‐experimental settings, including propensity score analysis, before‐after‐control‐impact studies, regression discontinuity design, and instrumental variables. Causal diagrams represent a unified approach to variable selection across methodologies and should be routinely applied in ecology research with causal implications.

Black, Indigenous and people of colour (BIPOC) individuals are disproportionately impacted by the negative consequences of our ongoing environmental and climate crises, yet their valuable scientific voices are shockingly underrepresented within the fields of Ecology and Evolutionary Biology (EEB). As early‐career BIPOC EEB researchers, we recognise the key role that our fields play in understanding and mitigating the effects of our ongoing global crises, and are concerned about the lack of diversity we see among our own EEB cohorts and mentors. We present this piece as a call to action for the EEB Academy, drawing on our own experiences and the literature to suggest steps the Academy must take to increase representation of and equity for BIPOC graduate scholars in EEB. We synthesise these steps into four actionable ideas: anti‐racism education and practice, increased funding opportunities, integration of diverse cultural perspectives and a community‐minded shift in PhDs. Importantly, this advice is specifically directed at those who wield power in the Academy (e.g. funding agencies, societies, institutions, departments and faculty), rather than BIPOC scholars already struggling against inequitable frameworks in EEB.