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1.
Folia Primatol (Basel) ; 91(2): 149-158, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31618728

RESUMO

Leucism is the lack or reduction in pigmentation in the most or parts of the body, but not in the eyes and body extremities. It is extremely rare in primates and has never been reported for Callithrix, a genus endemic to Brazil. We searched for individuals of Callithrix jacchus and C. penicillata with pigmentation anomalies in a systematic survey of three protected areas in the Atlantic Forest, within museum collections in Brazil, and opportunistically during field studies. Since 2008, we have recorded 8 individuals with leucism in small urban and periurban forest patches. Four were from native populations of C. penicillata in Cerrado savannahs and of C. jacchus in the Caatinga xeric scrubland, and 4 were from populations of hybrids between C. jacchus and C. penicillata in invaded areas in the coastal Atlantic Forest. We found no pigmentation abnormalities in museum specimens. We hypothesize that the observed leucism may be linked to inbreeding within the native range, but to hybridization within the invaded range, and discuss the likely ecological consequences to leucistic individuals.


Assuntos
Callithrix/fisiologia , Hibridização Genética , Pigmentação , Animais , Brasil , Callithrix/anatomia & histologia , Callithrix/genética , Feminino , Espécies Introduzidas , Masculino
2.
Ecology ; 100(1): e02525, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30317556

RESUMO

Primates play an important role in ecosystem functioning and offer critical insights into human evolution, biology, behavior, and emerging infectious diseases. There are 26 primate species in the Atlantic Forests of South America, 19 of them endemic. We compiled a dataset of 5,472 georeferenced locations of 26 native and 1 introduced primate species, as hybrids in the genera Callithrix and Alouatta. The dataset includes 700 primate communities, 8,121 single species occurrences and 714 estimates of primate population sizes, covering most natural forest types of the tropical and subtropical Atlantic Forest of Brazil, Paraguay and Argentina and some other biomes. On average, primate communities of the Atlantic Forest harbor 2 ± 1 species (range = 1-6). However, about 40% of primate communities contain only one species. Alouatta guariba (N = 2,188 records) and Sapajus nigritus (N = 1,127) were the species with the most records. Callicebus barbarabrownae (N = 35), Leontopithecus caissara (N = 38), and Sapajus libidinosus (N = 41) were the species with the least records. Recorded primate densities varied from 0.004 individuals/km2 (Alouatta guariba at Fragmento do Bugre, Paraná, Brazil) to 400 individuals/km2 (Alouatta caraya in Santiago, Rio Grande do Sul, Brazil). Our dataset reflects disparity between the numerous primate census conducted in the Atlantic Forest, in contrast to the scarcity of estimates of population sizes and densities. With these data, researchers can develop different macroecological and regional level studies, focusing on communities, populations, species co-occurrence and distribution patterns. Moreover, the data can also be used to assess the consequences of fragmentation, defaunation, and disease outbreaks on different ecological processes, such as trophic cascades, species invasion or extinction, and community dynamics. There are no copyright restrictions. Please cite this Data Paper when the data are used in publications. We also request that researchers and teachers inform us of how they are using the data.

3.
Naturwissenschaften ; 104(11-12): 92, 2017 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-29028068

RESUMO

Floral volatile organic compounds (VOCs) play important roles in plant-pollinator interactions. We investigated the reproductive ecology and floral VOCs of Zygopetalinae orchids to understand the relationship between floral scents and pollinators. We performed focal observations, phenological censuses and breeding system experiments in eight species in southeast Brazil. Floral scents were collected and analysed using SPME/GC-MS. We performed multivariate analyses to group species according to affinities of their VOCs and define compounds associated to each plant. Dichaea cogniauxiana was pollinated by weevils which use their developing ovules, while D. pendula was pollinated by the same weevils and perfume-collecting male euglossine bees. The other species were deceit-pollinated by bees. Zygopetalum crinitum was pollinated by carpenter bees, while W. warreana, Z. mackayi and Z. maxillare were bumblebee-pollinated. The latter was also pollinated by Centris confusa. Breeding system varied widely with no association to any pollinator group. Most VOCs are common to other floral scents. Zygopetalum crinitum presented an exclusive blend of VOCs, mainly composed of benzenoids. The scents of Pabstia jugosa, Promenaea xanthina and the Zygopetalum spp. were similar. The bumblebee-pollinated species have flowering periods partially overlapped, thus neither phenology nor pollinators constitute hybridization barriers among these species. Euglossines are not the only pollinators of Zygopetalinae. Different VOCs, size and lifespan of flowers are associated with distinct pollinators. A distinctive VOC bouquet may determine specialisation in carpenter bees or male euglossines within bee-pollinated flowers. Finally, visitation of deceit-pollinated flowers by perfume-collecting euglossines allows us to hypothesise how pollination by this group of bees had evolved.


Assuntos
Abelhas/fisiologia , Flores/química , Orchidaceae/química , Orchidaceae/fisiologia , Polinização , Animais , Compostos Orgânicos Voláteis/metabolismo , Gorgulhos/fisiologia
4.
Animals (Basel) ; 12(20)2022 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-36290161

RESUMO

The tiger shark Galeocerdo cuvier (Péron & Lesueur, 1822) (Carcharhinidae) is classified as near-threatened along the Brazilian coast, in line with its global categorization. Although Rio de Janeiro, located in southeastern Brazil, is internationally identified as a priority shark conservation area, many shark species, including tiger sharks, are landed by both industrial and artisanal fisheries in this state. However, there is a lack of detailed information on the species capture pressures and records for the state of Rio de Janeiro. Therefore, the aims of this study were to expand the tiger shark record database and to improve upon future conservation and management strategies. Tiger shark records from four coastal Rio de Janeiro regions were obtained by direct observation. The information obtained from fishery colonies/associations, environmental guards, researchers, and scientific articles, totaling 23 records, resulted in an approximately 5-fold increase in the number of tiger shark records off the coast of the state of Rio de Janeiro. A possible seasonality pattern concerning the size of the captured/observed animals was noted, emphasizing the need to consider the coast of Rio de Janeiro as an especially relevant area for at least part of the life history of tiger sharks.

5.
Ann Bot ; 106(3): 413-9, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20622254

RESUMO

BACKGROUND AND AIMS: The period between the beginning of anthesis and flower senescence modulates the transport of pollen by pollinators among conspecific flowers, and its length may therefore influence reproductive success. This study evaluated whether floral longevity favours pollen removal from the anthers over fecundity (seed set) in an ornithophilous species that does not undergo pollen limitation. METHODS: Field investigations were conducted on floral longevity, nectar production, pollinator behaviour, and variations in fruit set (FS), mean number of seeds per fruit (MSF) and pollen removal by hummingbirds (PR) during the anthesis of Salvia sellowiana in south-east Brazil. KEY RESULTS: Anthesis of flowers exposed to pollinators lasted 4 d, as well as on flowers with pollen removed from the anthers or deposited on the stigma. The longevity of bagged flowers was significantly higher (approx. 9 d). FS and PR reached 87.2 and 90 %, respectively, in natural conditions. PR increased gradually over the period of anthesis; however, FS and MSF reached their maxima in the first hours of anthesis. Nectar production was continuous, but the secretion rate was reduced after pollination. The removal of nectar from non-pollinated flowers stimulated its production. CONCLUSIONS: The longevity of anthesis in S. sellowiana seems to be related to the mechanism of gradual dispensing of pollen, resulting in greater male reproductive success. This is in agreement with the pollen-donation hypothesis. The small number of ovules (four) of S. sellowiana and the high frequency and the foraging mode of its pollinators may favour the selection for floral longevity driven by male fitness in this system.


Assuntos
Aves/fisiologia , Flores , Pólen , Salvia/fisiologia , Sementes , Animais , Salvia/embriologia
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