Elaine E. Guevara

FOXP2 variation in great ape populations offers insight into the evolution of communication skills

The gene coding for the forkhead box protein P2 (FOXP2) is associated with human language disorders. Evolutionary changes in this gene are hypothesized to have contributed to the emergence of speech and language in the human lineage. Although FOXP2 is highly conserved across most mammals, humans differ at two functional amino acid substitutions from chimpanzees, bonobos and gorillas, with an additional fixed substitution found in orangutans. However, FOXP2 has been characterized in only a small number of apes and no publication to date has examined the degree of natural variation in large samples of unrelated great apes. Here, we analyzed the genetic variation in the FOXP2 coding sequence in 63 chimpanzees, 11 bonobos, 48 gorillas, 37 orangutans and 2 gibbons and observed undescribed variation in great apes. We identified two variable polyglutamine microsatellites in chimpanzees and orangutans and found three nonsynonymous single nucleotide polymorphisms, one in chimpanzees, one in gorillas and one in orangutans with derived allele frequencies of 0.01, 0.26 and 0.29, respectively. Structural and functional protein modeling indicate a biochemical effect of the substitution in orangutans, and because of its presence solely in the Sumatran orangutan species, the mutation may be associated with reported population differences in vocalizations.

Non-human primates avoid the detrimental effects of prenatal androgen exposure in mixed-sex litters: combined demographic, behavioral, and genetic analyses.

Producing single versus multiple births has important life history trade‐offs, including the potential benefits and risks of sharing a common in utero environment. Sex hormones can diffuse through amniotic fluid and fetal membranes, and females with male littermates risk exposure to high levels of fetal testosterone, which are shown to have masculinizing effects and negative fitness consequences in many mammals. Whereas most primates give birth to single offspring, several New World monkey and strepsirrhine species regularly give birth to small litters. We examined whether neonatal testosterone exposure might be detrimental to females in mixed‐sex litters by compiling data from long‐term breeding records for seven primate species (Saguinus oedipus; Varecia variegata, Varecia rubra, Microcebus murinis, Mirza coquereli, Cheirogaleus medius, Galago moholi). Litter sex ratios did not differ from the expected 1:2:1 (MM:MF:FF for twins) and 1:2:2:1 (MMM:MMF:MFF:FFF for triplets). Measures of reproductive success, including female survivorship, offspring‐survivorship, and inter‐birth interval, did not differ between females born in mixed‐sex versus all‐female litters, indicating that litter‐producing non‐human primates, unlike humans and rodents, show no signs of detrimental effects from androgen exposure in mixed sex litters. Although we found no evidence for CYP19A1 gene duplications—a hypothesized mechanism for coping with androgen exposure—aromatase protein evolution shows patterns of convergence among litter‐producing taxa. That some primates have effectively found a way to circumvent a major cost of multiple births has implications for understanding variation in litter size and life history strategies across mammals.

A simple, economical protocol for DNA extraction and amplification where there is no lab

Genetic analyses are well suited to address many research questions in the study of wild populations, yet species of interest often have distributions that are geographically distant from molecular laboratories, necessitating potentially lengthy transport of biological specimens. Performing basic genetic analyses on site would avoid the project delays and risks of sample quality decline associated with transport, as well as allow original specimens to remain in the country of origin. Further, diagnostic genetic assays performed in the field could provide real-time information allowing for more nimble adjustments to research plans and use of resources. To this end, we developed protocols for reliably performing front-end genetics bench work in the field, without the requirements of electricity or permanent shelter. We validated these protocols on buccal swabs collected during routine capturing of sifaka lemurs (Propithecus verreauxi) at Bezà Mahafaly Special Reserve in Southwest Madagascar and faecal samples collected from captive sifakas (P. coquereli) at the Duke Lemur Center. Our basic protocol pipeline involves a chelating resin based DNA extraction followed by whole genome amplification or polymerase chain reaction using reagents stored at ambient temperature and portable, compact equipment powered by a lightweight solar panel. We achieved a high success rate (>80%) in downstream procedures, demonstrating the promise of such protocols for performing basic genetic analyses in a broad range of field situations.

Celebrating fifty years of research at the Duke Lemur Center

This year marked the 50 anniversary of the Duke Lemur Center (DLC). Founded in 1966 by John Buettner-Janusch and Peter Klopfer, the DLC is currently home to more than 200 lemurs and, over the years, has become one of the world’s most renowned centers for lemur research. The DLC’s birthday bash was held in Durham, NC from September 21 through 23, 2016 The event was first and foremost a celebration of the DLC’s impact on lemur research, drawing a crowd of lemur scientists and enthusiasts from around the globe. Wednesday night’s opening reception kicked off with a welcome from the current DLC Director, Anne Yoder, and remarks from co-founder Peter Klopfer. The following twoday scientific symposium featured podium presentations on Thursday and Friday at the Duke Washington Inn and Golf Club. A poster session was held Thursday evening at the DLC, providing a welcome opportunity, despite the rain, for attendees to tour the recently renovated facilities. The symposium showcased research on cognition and behavior, physiology and aging, and conservation and health. Videos of all research presentations are available on the DLC’s YouTube channel.

The gateway to anthropology in st. Louis

T his year, St. Louis, Missouri, was host to the annual meeting of the American Association of Physical Anthropologists (AAPA), which took place March 25–28, 2015. More than 1,000 anthropologists from across the world met near St. Louis’s Gateway Arch, where exciting presentations covered a diverse array of topics, from genetics in Neanderthals to energetics in humans. New research explored physiology and competition in primatology and postcranial adaptations in functional morphology. Highlights also included the presentation of new fossils that promise to influence our current understanding of human evolution.