In our latest blog post, Talia Stelling-Wood dives into her new paper, Habitat variability in an underwater forest: Using a trait‐based approach to predict associated communities.

About the paper

Traditional approaches to community ecology have focused around broad-scale classifications based on taxonomic relatedness or gross morphology.  These approaches assume that intraspecific variation is low and, therefore, that all individuals within these groups are functionally equivalent. However, there is increasing evidence to suggest this is not the case.  Trait-based approaches, in comparison, offer an alternative approach to community ecology. These approaches view a community as a collection of individuals, each possessing a potentially unique combination of traits that affect their fitness within an environment.  By measuring the characteristics of individuals, these approaches are not constrained to taxonomic groups and have the potential to capture individual variability within communities.  However, whilst representing a potentially more intuitive way to assess ecosystem functioning, these approaches have received relatively less attention compared to traditional approaches, especially in marine systems.  Macroalgae are the major habitat-formers on temperate reefs and are known to display high phenotypic plasticity in response to local environmental conditions, making them a great candidate to test the usefulness of trait-based approaches in a marine system.  For our study, we quantified inter- and intra-specific variation in the morphology of macroalgae using morphological traits.  We then tested the relative importance of these morphological traits, and compared them to species identity in predicting the abundances of epifauna associated with macroalgae. 

These findings challenge the use of mean values to describe entire species groups and highlight the need to incorporate individuality into community ecology.

We documented extensive inter- and intra-specific morphological variation across six species of macroalgae.  This morphological variability occurred at several scales; between different species groups, between individuals within species groups and even within individuals.  This meant that identity alone was not a good predictor of algal morphology.  We then ranked morphological traits against species identity and found traits were more important than identity in predicting the abundance of macroalgal associated epifauna.  These findings challenge the use of mean values to describe entire species groups and highlight the need to incorporate individuality into community ecology.  More broadly, however, our study demonstrates the usefulness of trait-based approaches, highlighting the need from more wider applications of these approaches.

About the research

Habitat-formers play an extremely important role in regulating the availability of resources (food, habitat, refuge etc.) to a wide variety of organisms.  They are, however, increasingly under pressure from the impacts of human activities. A better understanding of these ecosystems is now more important than ever if we are to predict how they might respond to these pressures. Our study is just one example of the prevalence of intraspecific variability in nature and highlights the need for it to be incorporated into ecological research more widely.  By ignoring it, we are in fact ignoring a wealth of data that could help us improve our understanding of ecosystem functioning.  Currently, we are investigating what environmental factors are important in driving the morphological variability we see in macroalgae, in order to predict how they might respond to future environmental change.  We are also looking at what this morphological variability means for the communities that live on the macroalgae, as these organisms represent an important tropic link between primary producers and higher trophic levels and, therefore, changes to these communities could have significant cascading effects right up the food web.  

About the author

Looking forward, I think there are tough times ahead for us ecologists; however, I believe now more than ever the work we do is extremely important in order to better understand the changing world around us.

I like to say I have taken the scenic route to ecology.  Whilst my love for science has been long and true, when I left high school I originally enrolled in a Bachelor of Molecular Biotechnology.  I soon, however, discovered that lab life was not for me.  I transferred to a Bachelor of Arts and Sciences and it was there that I got hooked on ecology.  Towards the end of my degree I decided the ocean was where my heart truly lay, and so went on to do a Master by Coursework and then a Master of Philosophy both in marine ecology.  I am now in the very final months of my PhD in macroalgal ecology and have loved every single minute.  Looking forward, I think there are tough times ahead for us ecologists; however, I believe now more than ever the work we do is extremely important in order to better understand the changing world around us.