Variability in infant helping and sharing behaviors across the second and third years of life: Differential roles of target and socialization.

Infants can help and share in the second year of life. However, there is limited knowledge as to variability in these behaviors as a function of target (e.g., caregiver vs. unfamiliar adult) and the influence of caregiver support on infant prosocial behavior. Infants (N = 268, 124 female) at 1-2 years of age (M = 1.47, SD = .27) and again at 2-3 years of age (M = 2.48, SD = .26) participated in a helping task (with the caregiver or unfamiliar experimenter), a sharing task (with either target), and a free-play observation with their primary caregiver from which caregiver support was coded. The racial and ethnic composition of the sample consisted of 3% Asian, 10% Black, 20% Hispanic, 59% White, 1% mixed race, and 6% "other." Median family annual income was $50,000 to $59,000, and median caregiver education level was "some college." Infant helping favored caregivers at both time points. However, infant sharing did not differ by target for 1-2-year-olds, but 2-3-year-olds shared more with their caregivers than an unfamiliar experimenter. Additionally, infants' behaviors antecedent to the act of helping or sharing (e.g., latency to respond, checking behaviors, and looking duration toward the target) differed by target. Concurrent relations between caregiver support and helping and sharing were moderated by age and differed by time point. Caregiver support for 1-2-year-olds also longitudinally predicted an age-moderated relation with 2-3-year-olds' helping toward an unfamiliar experimenter. Theoretical implications for the role of socialization in the emergence of helping and sharing behaviors are discussed. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

New Microsatellite Markers for Genetic Studies on Sergentomyia schwetzi (Diptera: Psychodidae): A Suspected Vector of Leishmania infantum (Trypanosomatida: Trypanosomatidae) in the Canine Leishmaniasis Focus of Mont-Rolland, Senegal.

Visceral leishmaniasis is not endemic in West Africa, but prevalence of canine leishmaniasis and seroprevalence of Leishmania infantum infection in humans are high in the Mont Rolland community (Thiès region, Senegal). Previous studies in this area showed that Sergentomyia schwetzi could be the potential vector of Le. infantum. To precisely describe the biology and population structure of this potential vector, we identified eight novel microsatellite loci to characterize Se. schwetzi populations. We tested these loci in Se. schwetzi populations from five locations at Mont Rolland (Thiès, Senegal). All the loci were polymorphic, with a mean of 17.25 alleles (observed heterozygosity: 0.455). We did not detect any evidence of scoring errors due to stuttering and large allele dropout. Moreover, several of these loci were also amplified in six other sand fly species (Sergentomyia magna, Sergentomyia dubia, Sergentomyia minuta, Phlebotomus duboscqi, Phlebotomus perniciosus, and Phlebotomus ariasi). These preliminary results demonstrate the utility of these microsatellite markers for Se. schwetzi (and for the other sand fly species) population genetic studies.