Longitudinal evidence that older parents produce offspring with longer telomeres in a wild social bird.

As telomere length (TL) often predicts survival and lifespan, there is considerable interest in the origins of inter-individual variation in TL. Cross-generational effects of parental age on offspring TL are thought to be a key source of variation, but the rarity of longitudinal studies that examine the telomeres of successive offspring born throughout the lives of parents leaves such effects poorly understood. Here, we exploit TL measures of successive offspring produced throughout the long breeding tenures of parents in wild white-browed sparrow weaver () societies, to isolate the effects of within-parent changes in age on offspring TLs.

Altruistic bet-hedging and the evolution of cooperation in a Kalahari bird.

Altruism is globally associated with unpredictable environments, but we do not understand why. New theory has highlighted that unpredictable environments could favor the evolution of altruism if altruistic acts reduce environmentally induced variance in the reproductive success of relatives (“altruistic bet-hedging”). Here, we show that altruism does indeed reduce environmentally induced reproductive variance in a wild cooperative bird.

Agreement of stall-side and laboratory major crossmatch tests with the reference standard method in horses.

Background: Crossmatching is used to prevent life-threatening transfusion reactions in horses. Laboratory methods are laborious and technically challenging, which is impractical during emergencies.

Hypothesis/objectives: Evaluate agreement between a stall-side crossmatch kit (KIT) and a laboratory method (LAB) in horses with known and unknown blood types.

Telomere attrition predicts reduced survival in a wild social bird, but short telomeres do not.

Attempts to understand the causes of variation in senescence trajectories would benefit greatly from biomarkers that reflect the progressive declines in somatic integrity (SI) that lead to senescence. While telomere length has attracted considerable interest in this regard, sources of variation in telomere length potentially unrelated to declines in SI could, in some contexts, leave telomere attrition rates a more effective biomarker than telomere length alone. Here, we investigate whether telomere length and telomere attrition rates predict the survival of wild white-browed sparrow-weaver nestlings (Plocepasser mahali).