Acknowledgements

The Editors would like to thank the following people for their invaluable help and advice in the review of manuscripts between 1 August 2020 and 31 July 2021. If a reviewer helped with more than one manuscript, the number is indicated in parentheses. Abernethy, K., Stirling, UK Adams, T., Kasane, Botswana Adhikari, A., Kathmandu, Nepal Alempijevic, D., Boca Raton, USA Altrichter, M., Prescott, USA Andreone, F., Turin, Italy Appleton, M., Thetford, UK Arinaitwe, J., Nairobi, Kenya Aust, P., Johannesburg, South Africa Azat, C., Santiago, Chile Balint, L., Cambridge, UK Bauer, H., Tubney, UK Becker, H., Cambridge, UK Belhekar, V., Mumbai, India Bergl, R., Asheboro, USA Beton, D., Kyrenia, Cyprus Bingham, H., Cambridge, UK Bista, D., Kathmandu, Nepal Black, S., Canterbury, UK Blades, B., Oxford, UK Blake, J., Gainesville, USA Bonebrake, T., Hong Kong, China Borchers, D., St Andrews, UK Botton, M., New York City, USA Bowden, C., Sandy, UK Brack, I., Porto Alegre, Brazil Breuer, T., Berlin, Germany Brockelman, W.Y., Nakhon Pathom, Thailand Brockington, D., Sheffield, UK Brodie, J., Missoula, USA Byers, B., Falls Church, USA Caitano, H., Vitoria, Brazil Carignano Torres, P., São Paulo, Brazil Carter, N., Boise, USA Carvalho, V., Caucaia, Brazil Casella, L., Rome, Italy Ceballos, G., Mexico City, Mexico Chan, A., Fort Collins, USA Cheyne, S., Palangka Raya, Indonesia Chiarello, A., Belo Horizonte, Brazil Choudhary, S., Noida, India Cisneros-Montemayor, A., Vancouver, Canada Crema, L., Manaus, Brazil Cresswell, W., St Andrews, UK Davenport, T., Stone Town, Tanzania de Jong, Y.A., Nanyuki, Kenya Denninger Snyder, K., Fort Collins, USA Detwiler, K., Boca Raton, USA Diniz, M., Goiânia, Brazil Domínguez Tejo, H., Santo Domingo, Dominican Republic Donald, P., Cambridge, UK dos Santos, J., Maceió, Brazil Duckworth, W., Geneva, Switzerland (2) Dudley, N., Bristol, UK Dunn, M., London, UK Ehmke, G., Carlton, Australia Elliott, L., Gland, Switzerland Espinosa de los Monteros, A., Xalapa, Mexico Ferraz, K., Piracicaba, Brazil Fisher, B., Burlington, USA Fisher, R., San Diego, USA Fjeldså, J., Copenhagen, Denmark Formia, A., Libreville, Gabon Fruth, B., Liverpool, UK Fuller, T., Amherst, USA Gardner, M.F., Edinburgh, UK Garnett, S., Darwin, Australia (2) Geary, M., Chester, UK Ghanbari, S., Tabriz, Iran Gilbert, G., Glasgow, UK Gill, D., Cambridge, UK Gluszek, S., Cambridge, UK Goossens, B., Cardiff, UK Green, R., Cambridge, UK Groom, M., Bothell, USA Harihar, A., Uttaranchal