Research Highlights
Can dietary flexibility buffer species against climate-driven phenological mismatch?
Inspired by mid-twentieth century research, this study reconsidered the extent to which the Winter Moth—long considered tightly synchronised with Oak budburst—really depends on a single host tree.
Rearing more than 3,500 caterpillars from multiple UK populations on nine common tree species, I measured survival, growth, development time, and used these measures to estimate overall fitness.
The results revealed that Winter Moths perform well on a broad range of hosts, and in several cases better than on Oak itself, demonstrating substantial trophic generalism. This flexibility suggests that dietary breadth may buffer populations against climate-driven shifts in seasonal timing, challenging assumptions that phenological mismatch inevitably leads to ecological collapse.
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Weir, J. C. (2024). Trophic generalism in the winter moth: a model species for phenological mismatch. Oecologia 206:225–239.
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Can ecological and life-history traits buffer species against the impacts of climate-driven phenological mismatch?
Here, we re-examine how shifts in seasonal timing affect interactions between species, arguing that many ecological systems possess innate “buffering” mechanisms that reduce the fitness costs of being out-of-sync.
We describe three forms of buffering:
(i) mechanisms that reduce asynchrony;
(ii) reduce the effects of asynchrony;
(iii) and those that dampen year-to-year performance variability through portfolio effects.
Using the spring arboreal caterpillar guild as a model system, we discuss the significance of buffers, show that they are widespread, and consider how they can make trophic interactions more resilient to climate change than is often assumed. This challenges the view that phenological mismatch is invariably detrimental, and prompts us to reconsider the ecological importance of mismatch in a changing climate.
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Weir, J. C. & Phillimore, A. B. (2024). Buffering and phenological mismatch: a change of perspective. Global Change Biology 30: e17294.
Does the current evidence support claims that climate-induced phenological mismatch is widespread and harmful?
We conducted a systematic literature review to evaluate how robustly existing evidence supports the idea that phenological synchrony arising due to climate change negatively affects consumers across ecological systems. ​​
We defined five criteria needed to demonstrate temperature-mediated mismatch and then assessed 109 studies spanning 129 taxa to see how many of these criteria each study tested.
We found that very few existing studies meet all criteria—most studies address only one or two—and that research is heavily biased toward particular regions and consumer types, revealing that the evidence base for broad, general conclusions about mismatch is surprisingly weak. This work highlights major gaps in our understanding of how climate change impacts trophic interactions and calls for more comprehensive and rigorous studies worldwide.
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Samplonius, J. M., Atkinson, A., Hassall, C., Keogan, K., Thackeray, S. J., Assmann, J. J., Burgess, M. D., Johansson, J., Macphie, K. H., Pearce-Higgins, J. W., Simmonds, E. G., Varpe, Ø., Weir, J. C., Childs, D. Z., Cole, E. F., Daunt, F., Hart, T., Lewis, O. T., Pettorelli, N., Sheldon, B. C., & Phillimore, A. B. (2021). Strengthening the evidence base for temperature-mediated phenological asynchrony and its impacts.
Nature Ecology & Evolution 5:155–164.
What are the highest-priority research challenges for entomology in a rapidly changing world?
This study brought together entomologists from across disciplines and career stages to identify the grand challenges facing entomological science over the coming decades. Using an open, four-stage prioritisation process with input from nearly 200 members of the Royal Entomological Society, the team distilled 710 challenges into 61 key research, technology, conservation, and engagement priorities spanning fundamental science, impacts of anthropogenic change, ecosystem services, and training and collaboration. These priorities range from strengthening insect monitoring networks and taxonomy to understanding insect declines, ecosystem roles, and integrating professional and amateur efforts - all are crucial for addressing biodiversity loss, human health, and environmental change. The paper highlights not only scientific questions but also the societal and institutional actions needed to advance entomology’s contributions to global sustainability.
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Luke, S. H., Roy, H. E., Thomas, C. D., Tilley, L. A. N., Ward, S., Watt, A., Carnaghi, M., Jaworski, C. C., Tercel, M. P. T. G., Woodrow, C., Aown, S., Banfield-Zanin, J. A., Barnsley, S. L., Berger, I., Brown, M. J. F., Bull, J. C., Campbell, H., Carter, R. A. B., Charalambous, M., Cole, L. J., Ebejer, M. J., Farrow, R. A., Fartyal, R. S., Grace, M., Highet, F., Hill, J. K., Hood, A. S. C., Kent, E. S., Krell, F. T., Leather, S. R., Leybourne, D. J., Littlewood, N. A., Lyons, A., Matthews, G., McNamara, L., Menéndez, R., Merrett, P., Mohammed, S., Murchie, A. K., Noble, M., Paiva, M. R., Pannell, M. J., Phon, C. K., Port, G., Powell, C., Rosell, S., Sconce, F., Shortall, C. R., Slade, E. M., Sutherland, J. P., Weir, J. C., Williams, C. D., Zielonka, N. B., and Dicks, L. V.(2023). Grand challenges in entomology: Priorities for action in the coming decades.
Insect Conservation and Diversity 16:173–189.
Does predator search image use drive the evolution of colour polymorphism in winter-active moths?
Inspired by a stray remark in Bernard Kettlewell's classic 1979 book The Evolution of Melanism, I investigated why many species of British moths that are active in winter show striking colour pattern variation. Kettlewell argued that visual diversity helps them evade visually-hunting bird predators.
Using a dual approach of field-based and comparative analytical methods, I placed artificial moth models of different colour morphs in woodlands at varying frequencies and observed predation by wild birds, as well as examining patterns of polymorphism occurrence across species.
I found that rarer colour forms were less likely to be eaten and that more polymorphic species tend to be more abundant. Both lines of evidence support the idea that predator “search images” favour rare forms in nature, and help maintain colour diversity through negative frequency-dependent selection. The findings shed light on how predator–prey interactions can shape and maintain genetic and phenotypic variation in natural populations.
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Weir, J. C. (2018). The evolution of colour polymorphism in British winter-active Lepidoptera in response to search image use by avian predators.
Journal of Evolutionary Biology 31:1109–1126.
Do predator “search images” drive the evolution of colour polymorphism?
In this synthesis paper, I explore how the way predators perceive their environment can actively generate and maintain striking colour diversity in otherwise cryptic species. When visually hunting predators focus on a common prey form, they may form a “search image” that improves detection of that morph while causing rarer forms to be overlooked — a process known as 'apostatic' (or negative frequency-dependent) selection. Reviewing classic theory alongside modern experimental and field evidence, the paper evaluates how strongly this mechanism is supported, where the evidence remains incomplete, and how perception and cognition shape evolutionary outcomes. The piece reframes polymorphism not as a paradox of imperfect camouflage, but as a dynamic adaptation to the limits of predator attention.
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Weir, J. C. (2021). Search image-driven apostatic selection and the evolution of phenotypic polymorphism. eLS 2:1-10