Assortative mating by telomere length under different environmental conditions in the brown booby, a long-lived seabird

Life-history strategies covary with a suite of behavioral and physiological responses along a slow-fast continuum, known as pace-of-life-syndrome. Particularly in long-lived species, pace-of-life is expected to influence breeding strategies, making it a potentially important factor in mate choice. It has been proposed that telomere length (TL) may integrate individual physiological components and survival prospects that underlie individual differences in pace-of-life. In the brown booby (Sula leucogaster), a long-lived seabird, we investigated whether TL may indicate individual pace-of-life by examining how it relates to mitochondrial DNA copy number (mtDNAcn), corticosterone (cort) levels, and skin coloration—a condition-dependent sexual trait. Then, we tested whether there is assortative mating by TL, and whether the degree of TL similarity between partners influences an individual’s likelihood of changing mates and physiological state (mtDNAcn and cort levels). Because environmental ...