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Article
Mari Rajala, Auteur ; Santtu Kareksela, Auteur ; Osmo Ratti, Auteur ; Jukka Suhonen, AuteurSurvivorship in animals depends on both foraging activities and avoidance of predation, and thus behavioural decisions often reflect a trade-off between predation risk and foraging efficiency. In this experimental study, we compared behavioural [...]
Article
Osmo Ratti, Auteur ; Ulriikka Ojanen, Auteur ; Pekka Helle, AuteurBlack flies (Simuliidae) have been observed to harass Black Grouse (Tetrao tetrix) in northern Finland during summer. We studied experimentally whether group size affects the attack rate of black flies on Black Grouse. The increase in flock size[...]
Article
Marja Isomursu, Auteur ; Osmo Ratti, Auteur ; Pekka Helle, Auteur ; Tuula Hollmen, AuteurParasite infections are often more common in male vertebrates than in females. Sexual selection leading to dimorphism can cause sexual differences in immune defence, behaviour or body size. Possible proximate explanations for male bias in parasi[...]
Article
Marja Isomursu, Auteur ; Osmo Ratti, Auteur ; Tuija Liukkonen, Auteur ; Pekka Helle, AuteurInbreeding can have a negative influence on several life-history traits as well as disease resistance in birds and mammals through different genetic mechanisms. Endangered and declining populations may be at particular risk for inbreeding. The l[...]
