Genetic structure of red-handed howler monkey populations in the fragmented landscape of Eastern Brazilian Amazonia

Abstract

We genotyped 15 microsatellite loci in order to evaluate the effects of habitat fragmentation, caused by flooding of the Tucuruí reservoir, on the genetic structure of Alouatta belzebul in eastern Amazonia. The analysis included two populations sampled in 1984, representing both margins of the Tocantins river, and three populations sampled 18 years later. Minimal differences in the diversity levels between present-day (Ho = 0.62-0.69 and AR = 6.07-7.21) and pre-flooding (Ho = 0.60-0.62 and A R = 6.27-6.77) populations indicated there was no significant loss of genetic variability, possibly because of successful management strategies applied during the flooding. The changes observed were limited to shifts in the composition of alleles, which presumably reflect the admixture of subpopulations during flooding. Given this, there were significant differences in the Rst values (p = 0.05) in all but one between-site comparison. Both present-day and original populations showed a deficit of heterozygotes, which suggests that this may be typical of the species, at least at a local level, perhaps because of specific ecological characteristics. The relatively large number of private alleles recorded in all populations may be a consequence of the Wahlund effect resulting from population admixture or a process of expansion rather than the loss of rare alleles through genetic drift. Additionally, the levels of genetic variability observed in this study were higher than those reported for other species of Neotropical primates, suggesting good fitness levels in these A. belzebul populations. Regular genetic monitoring of remnant populations, especially on islands, should nevertheless be an integral component of long-term management strategies.

Low genetic diversity and strong population structure shaped by anthropogenic habitat fragmentation in a critically endangered primate, Trachypithecus leucocephalus

“…The recent development of landscape genetic statistical tools allowed further assessment of the influence of environmental features on genetic patterns in endangered primates (Quéméré et al, 2010;. In addition, evaluation of genetic diversity, population structure and demographic history is increasingly incorporated into conservation studies, and has provided essential knowledge for assessing long-term population viability, defining appropriate conservation units and designing management strategies (Bastos et al, 2010;Chaves et al, 2011).…”

Diversidad genética en grupos de monos aulladores de manto (Alouatta palliata mexicana) en la Reserva de la Biosfera Los Tuxtlas (Veracruz, México)

“…La información existente indica que esta subespecie presenta bajos niveles de variación, que pueden ser producto ya sea de un evento de cuello de botella o un efecto fundador; ambos relacionados con la historia de colonización y expansión Marcadores moleculares utilizados en estudios que reportan variabilidad genética en diferentes especies de monos aulladores del género Alouatta. Referencias: A. belzebul (Schneider et al, 1991;Melo, Sampaio, Schneider y Schneider, 1992;Sampaio, Schneider y Schneider, 1996;Zaldívar et al, 2003;Gonçalves et al, 2004;Nascimento, Bonvicino, da Silva, Schneider y Seuanez, 2005;Nascimento, Bonvicino, de Oliveira, Schneider y Seuánez, 2008;Bastos, Gonçalves, Ferrari, Silva y Schneider, 2010). A. caraya (Szapkievich, Comas, Zunino y Mudry, 1998;Nascimento et al, 2005;Ascunce, Hasson, Mulligan y Mudry, 2007;Nascimento et al, 2007;Oklander, Zunino, Di Fiore y Corach, 2007;Ruiz-García et al, 2007;Oklander et al, 2010;Collevatti, Souza-Neto, Silva-Jr y Telles, 2013;Oklander y Corach, 2013).…”

Kin structure and parallel dispersal in the black-and-gold howler monkey Alouatta caraya (Platyrrhini, Atelidae)

“…Although it was suggested that the southernmost species of the Alouatta genus presents higher levels of genetic diversity, with diversity declining to the north (Ellsworth and Hoelzer, 2006), results found so far show a wide variation in genetic diversity, suggesting that, in addition to the history of migration and colonization, many other factors are likely responsible for the present patterns in genetic diversity, such as the level and time since fragmentation and habitat disturbance, bottlenecks due to habitat destruction, catastrophes, and diseases (Pavelka et al, 2003;Oklander et al, 2010). The lack of a fragmentation effect, and high genetic diversity (mean H O = 0.65) were also found for the red-handed howler (Alouatta belzebul) in populations from the low Tocantins River, eastern Amazonia (Bastos et al, 2010). An isolated population of the mantled howler monkey, A. palliata, from Barro Colorado Island also presented high levels of genetic diversity (H E = 0.584 ± 0.063) and no effect of fragmentation (Milton et al, 2009).…”