Influence of incubation temperature, maternal effects, and paternity on quality of olive ridley hatchlings (Lepidochelys olivacea) from a mass-nesting beach in the Mexican Pacific.

Future climate change scenarios project that the increase in surface temperatures will affect ocean temperatures, inducing shifts in marine biodiversity. Sea turtles are species that are particularly vulnerable to the effects of climate change because temperature is a factor that influences embryonic development. We collected clutches of olive ridley turtles from a mass-nesting beach in the Mexican Pacific, which were incubated in ex situ conditions. When the hatchlings emerged, we measured the body condition index-which evaluates the weight-length relationship-and swim thrust, both were considered traits associated with fitness, termed "fitness proxies," and evaluated the effects of incubation temperature, maternal effects, and paternity on these fitness proxies. The body condition index was correlated positively and significantly with the arribada month and temperature during the last third of the incubation period but showed an inverse relationship with the maternal effect. While swim thrust was positively correlated with the maternal effect and the arribada month, there was an inverse relationship with incubation temperature during the first third of the period. Paternity, whether single or multiple, did not have a significant effect on either fitness proxies; however, it may have effects on the average fitness of a population of hatchlings. These results underscore the need to expand research on the sublethal effects of high incubation temperatures on the adaptation and survival of sea turtles, particularly in scenarios of rapid climate change.

Regional variation in multiple paternity in the brown smooth-hound shark Mustelus henlei from the northeastern Pacific.

Multiple paternity (MP) in the brown smooth-hound shark (Mustelus henlei) was assessed in 15 litters (15 mothers and 97 embryos) collected in the northern Gulf of California of which 86.7% were sired by more than one male (i.e., from 2 to 4 sires). When taken together with results from previous studies, this record indicates that there is regional variation in MP in M. henlei in the northeastern Pacific. This pattern is associated with variations in the reproductive traits of each population (e.g., female size and litter size). In the Gulf of California, the results of a generalized linear model (GLZ) indicated that the litters of larger females had a higher probability of MP compared to those of smaller females.

Mating System of Caiman yacare (Reptilia: Alligatoridae) Described from Microsatellite Genotypes.

The yacare caiman (Caiman yacare) is a reptile from South America and 1 of the 2 crocodilian species present in Argentina. The degradation of their natural habitat and strong hunting pressure led to a sharp numerical decline of wild populations. Nowadays, C. yacare is included in Appendix II of CITES, and ranching practices in some areas in Argentina are helping hatching success. In this context, it is important to better understand the population structure and mating system of the species. To do this, we amplified 10 microsatellite markers (SSRs) in 148 individuals of 13 C. yacare nests. All of the markers were polymorphic with 2­12 alleles per locus, with allelic sizes ranging between 154 and 400 bp and medium levels of polymorphism (Ho = 0.152­0.551 and He = 0.221­0.621). We were able to determine the maternal genotype in 9 out of 13 nests. In 6 of them we found more than 1 paternal genotype, with a maximum of 3 fathers for a single nest. This study is the first to provide evidence of multiple paternity behavior. These findings will be useful to improve management and conservation strategies for the species.

Multiple Paternity in the Norway Rat, Rattus norvegicus, from Urban Slums in Salvador, Brazil.

The Norway rat, Rattus norvegicus, is one of the most important pest species globally and the main reservoir of leptospires causing human leptospirosis in the urban slums of tropical regions. Rodent control is a frequent strategy in those settings to prevent the disease but rapid growth from residual populations and immigration limit the long-term effectiveness of interventions. To characterize the breeding ecology of R. norvegicus and provide needed information for the level of genetic mixing, which can help identify inter-connected eradication units, we estimated the occurrence of multiple paternity, distances between mothers and sires, and inbreeding in rats from urban slum habitat in Salvador, Brazil. We genotyped 9 pregnant females, their 66 offspring, and 371 males at 16 microsatellite loci. Multiple paternity was observed in 22% (2/9) of the study litters. Of the 12 sires that contributed to the 9 litters, we identified 5 (42%) of those sires among our genotyped males. Related males were captured in close proximity to pregnant females (the mean inter-parent trapping distance per litter was 70 m, ±58 m SD). Levels of relatedness between mother-sire pairs were higher than expected and significantly higher than relatedness between all females and non-sire males. Our findings indicate multiple paternity is common, inbreeding is apparent, and that mother-sire dyads occur in close proximity within the study area. This information is relevant to improve the spatial definition of the eradication units that may enhance the effectiveness of rodent management programs aimed at preventing human leptospirosis. High levels of inbreeding may also be a sign that eradication efforts are successful.

Evidence of polygamy in the socially monogamous Amazonian fish Arapaima gigas (Schinz, 1822) (Osteoglossiformes, Arapaimidae)

Arapaima gigas is one of the largest freshwater fishes of the world. It is socially monogamous, forming pairs, constructing a nest and providing parental care. We performed a paternity analysis under three scenarios in captive, semi-natural and natural areas using 10 microsatellite markers. As a positive control, we analyzed three pairs and their offspring isolated individually in artificial breeding ponds (a priori very high probability of monogamy). We then analyzed two samples of offspring from large artificial ponds with multiple adults but only one reproductive pair (a priori high probability of monogamy), two samples from semi-natural breeding station with multiple adults but only one reproductive pair (a priori high probability of monogamy), and a sample from a natural lake with multiple adults, some potentially breeding (a priori medium probability of monogamy). Analysis of patterns of Mendelian heredity suggested an extra-pair contribution for all broods except the positive controls. Similarly, results based on multilocus analysis estimated at least two sib-groups per nest. These results reject monogamy as a system of breeding in Arapaima gigas. From a management perspective, this behavior may be exploited to maintain genetic diversity in captive and as well in wild populations of Arapaima gigas.

O pirarucu Arapaima gigas é um dos maiores peixes de água doce do mundo. É socialmente monogâmico, forma casais, constrói ninhos e fornece cuidado parental. Com o objetivo de acessar o sistema de acasalamento do pirarucu, analisamos três cenários: em áreas de cativeiro, semi-naturais e naturais, utilizando 10 marcadores microssatélites. Como controle positivo, analisamos três casais e suas ninhadas isolados em açudes individuais (probabilidade a priori muito alta de monogamia). A seguir, analisamos duas amostras de ninhadas de um açude com vários adultos, mas somente um casal reprodutivo (probabilidade a priori alta de monogamia), duas amostras de estação de criação semi-natural com vários adultos mas somente um casal reprodutivo (probabilidade a priori alta de monogamia), e uma amostra de lago natural com vários adultos alguns potencialmente em fase de reprodução (probabilidade a priori média de monogamia). Análises de padrões mendelianos de hereditariedade sugerem contribuição extra-par para todas as ninhadas, exceto as do controle positivo. Similarmente, resultados baseados em análises multilocus realizadas no programa KINALYZER estimaram pelo menos dois grupos-irmãos por ninhada. Nossos resultados rejeitam a monogamia como sistema de acasalamento em Arapaima gigas. Da perspectiva de manejo, esse comportamento pode ser explorado para manter a diversidade genética em cativeiro assim como em populações naturais de Arapaima gigas.

Evidence of polygamy in the socially monogamous Amazonian fish Arapaima gigas (Schinz, 1822) (Osteoglossiformes, Arapaimidae)

Arapaima gigas is one of the largest freshwater fishes of the world. It is socially monogamous, forming pairs, constructing a nest and providing parental care. We performed a paternity analysis under three scenarios in captive, semi-natural and natural areas using 10 microsatellite markers. As a positive control, we analyzed three pairs and their offspring isolated individually in artificial breeding ponds (a priori very high probability of monogamy). We then analyzed two samples of offspring from large artificial ponds with multiple adults but only one reproductive pair (a priori high probability of monogamy), two samples from semi-natural breeding station with multiple adults but only one reproductive pair (a priori high probability of monogamy), and a sample from a natural lake with multiple adults, some potentially breeding (a priori medium probability of monogamy). Analysis of patterns of Mendelian heredity suggested an extra-pair contribution for all broods except the positive controls. Similarly, results based on multilocus analysis estimated at least two sib-groups per nest. These results reject monogamy as a system of breeding in Arapaima gigas. From a management perspective, this behavior may be exploited to maintain genetic diversity in captive and as well in wild populations of Arapaima gigas.(AU)

O pirarucu Arapaima gigas é um dos maiores peixes de água doce do mundo. É socialmente monogâmico, forma casais, constrói ninhos e fornece cuidado parental. Com o objetivo de acessar o sistema de acasalamento do pirarucu, analisamos três cenários: em áreas de cativeiro, semi-naturais e naturais, utilizando 10 marcadores microssatélites. Como controle positivo, analisamos três casais e suas ninhadas isolados em açudes individuais (probabilidade a priori muito alta de monogamia). A seguir, analisamos duas amostras de ninhadas de um açude com vários adultos, mas somente um casal reprodutivo (probabilidade a priori alta de monogamia), duas amostras de estação de criação semi-natural com vários adultos mas somente um casal reprodutivo (probabilidade a priori alta de monogamia), e uma amostra de lago natural com vários adultos alguns potencialmente em fase de reprodução (probabilidade a priori média de monogamia). Análises de padrões mendelianos de hereditariedade sugerem contribuição extra-par para todas as ninhadas, exceto as do controle positivo. Similarmente, resultados baseados em análises multilocus realizadas no programa KINALYZER estimaram pelo menos dois grupos-irmãos por ninhada. Nossos resultados rejeitam a monogamia como sistema de acasalamento em Arapaima gigas. Da perspectiva de manejo, esse comportamento pode ser explorado para manter a diversidade genética em cativeiro assim como em populações naturais de Arapaima gigas.(AU)

An opportunity for testing multiple paternity in a wild Jaguar (Panthera onca) / Uma oportunidade para testar múltipla paternidade em onça selvagem (Panthera onca)

We performed a paternity test for three cubs from one wild female jaguar (Panthera onca). The opportunity for this study was generated by an accident involving a vehicle collision with a pregnant jaguar in the central Amazon. The cubs are polyzygotic triplets and were found to have been sired by the same male. Here, we also provide an overview and discuss several aspects of jaguar reproduction.

Nós realizamos um teste de paternidade em três filhotes de uma onça selvagem (Panthera onca). A oportunidade para este estudo foi criada a partir de um acidente envolvendo a colisão entre um veículo e uma onça grávida na Amazônia central. Os filhotes são trivitelinos e foram gerados por um mesmo macho. Neste estudo nós também oferecemos uma revisão e discutimos aspectos da reprodução de onças.

Genetic Evidence for Polygamy as a Mating Strategy in Caiman crocodilus.

The mating system of the spectacled caiman (Caiman crocodilus) was investigated in the Piagaçu-Purus Sustainable Development Reserve, Amazonas, Brazil. We used 6 polymorphic microsatellite loci to genotype 13 females and 174 hatchlings representing 20 nests sampled over 4 consecutive reproductive seasons (2007-2010). Paternity was determined by 2 methods: simple counts, and statistical analysis using Gerud 2.0. Results were congruent between the 2 approaches, and the null hypothesis of single paternity was rejected in 19 of the 20 nests analyzed, thereby demonstrating that C. crocodilus females are polyandrous and that the breeding system of the species can be characterized as polygamous. The data suggest that 1-4 fathers were responsible for the paternity of the offspring, and that the males contributed differently (9-100%) to each of the 20 nests. A total of 53 males copulated with the 20 females mothering the nests. This is the first study on the mating system of C. crocodilus and the frequency of multiple paternity is among the highest values (95%) reported thus far for crocodilians.