parental contributions, fish, parent-offspring contact


Males and females may make distinctly different contributions to parental care. In cichlid fishes, females typically care for embryos while males guard territories. Parent-offspring contact may enhance transmission of beneficial microbes. Microbial sharing between group members is a potential mechanism for the evolution of social behavior (Lombardo 2007). Parental care is unusual among teleost (bony) fishes, but is ubiquitous among the cichlid fishes, and convict cichlids (Archocentrus nigrofaciatus) exhibit biparental care. We (1) quantified the parental behavior of males and females to determine whether they differed in amount or type of physical contact with their offspring; (2) collected samples of parental slime coats, embryos, and fry to compare the microbes associated with each, comparing samples from subsets of broods receiving parental care to others where parental contact was prevented. Females touched embryos significantly more often than males, but physical contact with fry is much less common and initiated by fry rather than parents. To date, molecular data support our prediction that fry receiving parental care bear microbes more similar to female vs. male parents, and to parents vs. siblings that did not receive care. Assuming this trend continues in subsequent samples, we conclude that parents are an important source of microbial inocula and that female contact during immobile developmental stages is especially important for microbial transmission.