Russo, Sabrina E., McMahon, Sean M., Detto, Matteo, Ledder, Glenn, Wright, S. Joseph, Condit, Richard S., Davies, Stuart J., Ashton, Peter S., Bunyavejchewin, Sarayudh, Chang-Yang, Chia-Hao, Ediriweera, Sisira, Ewango, Corneille E. N., Fletcher, Christine, Foster, Robin B., Gunatilleke, C. V. Savi, Gunatilleke, I. A. U. Nimal, Hart, Terese, Hsieh, Chang-Fu, Hubbell, Stephen P., Itoh, Akira, Kassim, Abdul Rahman, Leong, Yao Tze, Lin, Yi Ching, Makana, Jean-Remy, Mohamad, Mohizah Bt et al. 2020. "The interspecific growth-mortality trade-off is not a general framework for tropical forest community structure." Nature Ecology & Evolution, https://doi.org/10.1038/s41559-020-01340-9.
Using demographic data for 1,111 tree species across ten tropical forests, the authors test the generality of the growth-mortality trade-off, finding that it holds in undisturbed but not disturbed forests. Resource allocation within trees is a zero-sum game. Unavoidable trade-offs dictate that allocation to growth-promoting functions curtails other functions, generating a gradient of investment in growth versus survival along which tree species align, known as the interspecific growth-mortality trade-off. This paradigm is widely accepted but not well established. Using demographic data for 1,111 tree species across ten tropical forests, we tested the generality of the growth-mortality trade-off and evaluated its underlying drivers using two species-specific parameters describing resource allocation strategies: tolerance of resource limitation and responsiveness of allocation to resource access. Globally, a canonical growth-mortality trade-off emerged, but the trade-off was strongly observed only in less disturbance-prone forests, which contained diverse resource allocation strategies. Only half of disturbance-prone forests, which lacked tolerant species, exhibited the trade-off. Supported by a theoretical model, our findings raise questions about whether the growth-mortality trade-off is a universally applicable organizing framework for understanding tropical forest community structure.
