Omer, A. H. A.; Fristoe, T.; Yang, Q.; Maurel, N.; Weigelt, P.; Kreft, H.; Bleilevens, J.; Dawson, W.; Essl, F.; Pergl, J. et al.; Pyšek, P.; van Kleunen, M.: Characteristics of the naturalized flora of Southern Africa largely reflect the non-random introduction of alien species for cultivation. Ecography 44 (12), pp. 1812 - 1825 (2021)

Omer, A. H. A.; Kordofani, M.; Gibreel, H. H.; Pysek, P.; van Kleunen, M.: The alien flora of Sudan and South Sudan: Taxonomic and biogeographical composition. Biological Invasions 23 (7), pp. 2033 - 2045 (2021)

Papageorgiou, D.; Rozen-Rechels, D.; Nyaguthii, B.; Farine, D. R.: Seasonality impacts collective movements in a wild group-living bird. BMC Movement Ecology 9 (1), 38 (2021)

Poblete, Y.; Botero‐Delgadillo, E.; Espindola-Hernandez, P.; Südel, G.; Vásquez, R. A.: Female extra‐pair behavior is not associated with reduced paternal care in Thorn‐tailed Rayadito. Ecology and Evolution 11 (7), pp. 3065 - 3071 (2021)

Poblete, Y.; Botero‐Delgadillo, E.; Espindola-Hernandez, P.; Vásquez, R. A.: Risk‐taking behaviour relates to timing of breeding in a sub‐Antarctic rainforest bird. Ibis 163 (3), pp. 812 - 823 (2021)

Quirici, V.; Botero‐Delgadillo, E.; González-Gómez, P. L.; Espindola-Hernandez, P.; Zambrano, B.; Cuevas, E.; Wingfield, J. C.; Vásquez, R. A.: On the relationship between baseline corticosterone levels and annual survival of the thorn-tailed rayadito. General and Comparative Endocrinology 300, 113635 (2021)

Rohr, V. A.; Volkmer, T.; Metzler, D.; Küpper, C.: Neoptile feathers contribute to outline concealment of precocial chicks. Scientific Reports 11, 5483 (2021)

Rollins, R. E.; Schaper, S.; Kahlhofer, C.; Frangoulidis, D.; Strauß, A. F. T.; Cardinale, M.; Springer, A.; Strube, C.; Bakkes, D. K.; Becker, N. S. et al.; Chitimia-Dobler, L.: Ticks (Acari: Ixodidae) on birds migrating to the island of Ponza, Italy, and the tick-borne pathogens they carry. Ticks and Tick-borne Diseases 12 (1), 101590 (2021)

Safari, I.; Goymann, W.: The evolution of reversed sex roles and classical polyandry: Insights from coucals and other animals. Ethology 127 (1), pp. 1 - 13 (2021)

Santema, P.; Kempenaers, B.: Offspring provisioning by extra‐pair males in blue tits. Journal of Avian Biology 52 (5), e02755 (2021)

Santema, P.; Schlicht, L.; Beck, K. B.; Kempenaers, B.: Effects of exposure to predator models on fledging behaviour in blue tits. Animal Behaviour 181, pp. 61 - 69 (2021)

Santema, P.; Schlicht, L.; Beck, K. B.; Sheldon, B. C.; Kempenaers, B.: Why do nestling birds fledge early in the day? Animal Behaviour 174, pp. 79 - 86 (2021)

Santema, P.; Schlicht, L.; Sheldon, B. C.; Kempenaers, B.: Experimental evidence that nestlings adjust their fledging time to each other in a multiparous bird. Animal Behaviour 180, pp. 143 - 150 (2021)

Santema, P.; Teltscher, K. L.; Kempenaers, B.: Sperm numbers on the perivitelline layers of blue tit eggs are repeatable within a clutch, but independent of the occurrence of extra-pair paternity. Journal of Avian Biology 52 (10), e02826 (2021)

Schlicht, E.; Kempenaers, B.: Origin and outcome of social polygyny in the Blue Tit. Ardea 109 (1), pp. 91 - 118 (2021)

Shaftel, R.; Rinella, D. J.; Kwon, E.; Brown, S. C.; Gates, H. R.; Kendall, S.; Lank, D. B.; Liebezeit, J. R.; Payer, D. C.; Rausch, J. et al.; Saalfeld, S. T.; Sandercock, B. K.; Smith, P. A.; Ward, D. H.; Lanctot, R. B.: Predictors of invertebrate biomass and rate of advancement of invertebrate phenology across eight sites in the North American Arctic. Polar Biology 44 (2), pp. 237 - 257 (2021)

Sládeček, M.; Brynychová, K.; Elhassan, E.; Šálek, M. E.; Janatová, V.; Vozabulová, E.; Chajma, P.; Firlová, V.; Pešková, L.; Almuhery, A. et al.; Bulla, M.: Diel timing of nest predation changes across breeding season in a subtropical shorebird. Ecology and Evolution 11 (19), pp. 13101 - 13117 (2021)

Sridhar, V. H.; Li, L.; Gorbonos, D.; Nagy, M.; Schell, B.; Sorochkin, T.; Gov, N. S.; Couzin, I. D.: The geometry of decision-making in individuals and collectives. Proceedings of the National Academy of Sciences of the United States of America 118 (50), e2102157118 (2021)

Stidsholt, L.; Greif, S.; Goerlitz, H. R.; Beedholm, K.; Macaulay, J.; Johnson, M.; Madsen, P. T.: Hunting bats adjust their echolocation to receive weak prey echoes for clutter reduction. Science Advances 7 (10), eabf1367 (2021)

Stidsholt, L.; Johnson, M.; Goerlitz, H. R.; Madsen, P. T.: Wild bats briefly decouple sound production from wingbeats to increase sensory flow during prey captures. iScience 24 (8), 102896 (2021)