Reciprocal recognition of sifaka (<Emphasis Type="Italic">Propithecus verreauxi verreauxi</Emphasis>) and redfronted lemur (<Emphasis Type="Italic">Eulemur fulvus rufus</Emphasis>) alarm calls

Redfronted lemurs (Eulemur fulvus rufus) and Verreaux's sifakas (Propithecus verreauxi verreauxi) occur sympatrically in western Madagascar. Both species exhibit a so-called mixed alarm call system with functionally referential alarm calls for raptors and general alarm calls for carnivores and raptors. General alarm calls also occur in other contexts associated with high arousal, such as inter-group encounters. Field playback experiments were conducted to investigate whether interspecific recognition of alarm calls occurs in both species, even though the two species rarely interact. In a crossed design, redfronted lemur and sifaka alarm calls were broadcast to individuals of both species, using the alarm call of chacma baboons (Papio cynocephalus) as a control. Both species responded with appropriate escape strategies and alarm calls after playbacks of heterospecific aerial alarm calls. Similarly, they reacted appropriately to playbacks of heterospecific general alarm calls. Playbacks of baboon alarm calls elicited no specific responses in either lemur species, indicating that an understanding of interspecific alarm calls caused the responses and not alarm calls in general. Thus, the two lemur species have an understanding of each other's aerial as well as general alarm calls, suggesting that even in species that do not form mutualistic associations and rarely interact, common predator pressure has been sufficient for the development of heterospecific call recognition.     

How Lesbian and Heterosexual Parents Convey Attitudes about Gender to their Children: The Role of Gendered Environments

We studied associations among parents’ gender role attitudes, gender stereotyping in children’s environments, and children’s gender role attitudes and whether these associations were similar for families with lesbian and heterosexual parents. Fifty-seven 4- to 6-year-olds and 114 parents from the US participated. Parents completed self-report questionnaires and responded to interview questions. Researchers collected data regarding the child’s environment and attitudes about gender. Results revealed that children with lesbian mothers had less stereotyped environments and less traditional attitudes. Parental attitudes were associated with stereotyping in children’s environments and with children’s attitudes about gender. Both for lesbian and heterosexual parents, the impact of parents’ attitudes on children’s attitudes was partially mediated by the nature of children’s environments.