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Browsing by Author "Freitas, Tamira"

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  • Frequency of the CCR5-A32 mutation in the Atlantic island populations of Madeira, the Azores, Cabo Verde, and São Tomé e Príncipe
    Publication . Freitas, Tamira; Brehm, António; Fernandes, Ana Teresa
    There is evidence thathe CCR5-A32 mutation confers protection against HIV-1 infection tohomozygous individuals. It is believed that this mutation spread through Europe with the Vikings and that it has been subjected to positive selection, leading to a high frequency in Europe (-10%). We carried out the present study to determine the 32-bp deletion allele and genotype frequencies of the CCR5 gene (CCR5-A32 ) in the Atlantic island populations of Madeira, the Azores, Cabo Verde, and Säo Tomé e Principe. These Atlantic archipelagos were all colonized by the Portuguese in the 15th and 16th centuries, but the latter two received most of their settlers from the West African coast. The frequency of the CCR5-A32 mutation varies between 0% in Säo Tomé e Principe and 16.5% in the Azores. The Azores Islands have one of the highest frequencies of homozygotes found in Europe (4.8%). There are significant differences (P < 0.05) between some of these populations, for example, between Säo Tomé e Principe and Cabo Verde, and even within populations (e.g., Portugal, Madeira, and the Azores).
    2006Journal article Open access Show more
  • Genetic identity of Pipistrellus maderensis from the Madeira archipelago: a first assessment, and implications for conservation
    Publication . Jesus, José; Teixeira, Sérgio; Freitas, Tamira; Teixeira, David; Brehm, Antonio
    According to the IUCN global Red List, Pipistrellus maderensis is among the most endangered bat species in Europe. Its populations are scattered across some islands of the Atlantic Ocean, particularly Madeira and the Canary archipelagoes. This geographical pattern is likely to result in significant genetic differences between populations which would have important implications to set conservation priorities. To test this hypothesis, we analyze cytochrome b sequences and compared populations from Madeira and the Canary islands. Five sequences from Madeiran individuals were analysed and compared to 30 sequences extracted from GenBank from Pipistrellus maderensisfrom the Canary islands and Pipistrellus kuhli. Our results indicate a significant divergence between the two groups, smaller than between true species, but higher that intra-group divergence. However, further research on the Madeiran popula tion is needed, including the use of sequences of other mitochondrial markers and nuclear marker and microsatellites
    2013Journal article Open access Show more
  • MAMMALS IN PORTUGAL: A data set of terrestrial, volant, and marine mammal occurrences in Portugal
    Publication . Grilo, Clara; Afonso, Beatriz C.; Afonso, Filipe; Alexandre, Marta; Aliácar, Sara; Almeida, Ana; Alonso, Ivan Prego; Álvares, Francisco; Alves, Paulo; Alves, Paulo Célio; Alves, Pedro; Jones, Kate E.; Laborde, Marina I.; de Oliveira, Luís Lamas; Leitão, Inês; Lemos, Rita; Lima, Cátia; Linck, Paloma; Lopes, Hugo; Lopes, Susana; López‐Baucells, Adrià; Amado, Anabela; Loureiro, Armando; Loureiro, Filipa; Lourenço, Rui; Lourenço, Sofia; Lucas, Paula; Magalhães, Ana; Maldonado, Cristina; Marcolin, Fabio; Marques, Sara; Marques, J. Tiago; Amendoeira, Vitor; Marques, Carina; Marques, Paulo; Marrecas, Pedro Caetano; Martins, Frederico; Martins, Raquel; Mascarenhas, Miguel; Mata, Vanessa A.; Mateus, Ana Rita; Matos, Milene; Medinas, Denis; Amorim, Francisco; Mendes, Tiago; Mendes, Gabriel; Mestre, Frederico; Milhinhas, Catarina; Mira, António; Monarca, Rita I.; Monteiro, Norberto; Monteiro, Barbara; Monterroso, Pedro; Nakamura, Mónia; da Silva Aparício, Guilherme; Negrões, Nuno; Nóbrega, Eva K.; Nóvoa, Miguel; Nunes, Manuel; Nunes, Nuno Jardim; Oliveira, Flávio; Oliveira, José Miguel; Palmeirim, Jorge M.; Pargana, João; Paula, Anabela; Araújo, Ricardo; Paupério, Joana; Pedroso, Nuno M.; Pereira, Guilherme; Pereira, Pedro F.; Pereira, José; Pereira, Maria João Ramos; Petrucci‐Fonseca, Francisco; Pimenta, Miguel; Pinto, Sara; Pinto, Nuno; Ascensão, Fernando; Pires, Rosa; Pita, Ricardo; Pontes, Carlos; Quaresma, Marisa; Queirós, João; Queirós, Luís; Rainho, Ana; da Graça Ramalhinho, Maria; Ramalho, Patrícia; Raposeira, Helena; Augusto, Margarida; Rasteiro, Francisco; Rebelo, Hugo; Regala, Frederico Tátá; Reto, Dyana; Ribeiro, Sérgio Bruno; Rio‐Maior, Helena; Rocha, Ricardo; Rocha, Rita Gomes; Rodrigues, Luísa; Román, Jacinto; Bandeira, Victor; Roque, Sara; Rosalino, Luís Miguel; do Rosário, Inês T.; Rossa, Mariana; Russo, Danilo; Sá, Pedro; Sabino‐Marques, Helena; Salgueiro, Vânia; Santos, Helena; Santos, Joana; Barbosa, A. Márcia; Santos, João P. V.; Santos, Nuno; Santos, Sara; Santos, Carlos Pedro; Santos‐Reis, Margarida; Serronha, Ana; Sierra, Pablo; Silva, Bruno; Silva, Carla S. G. M.; Silva, Clara; Barbosa, Soraia; Silva, Diogo; da Silva, Luís P.; Silva, Ricardo; Silva, Carmen; da Silva Júnior, Flavio Manoel Rodrigues; Sousa, Pedro; Sousa‐Guedes, Diana; Spadoni, Giulia; Tapisso, Joaquim T.; Teixeira, Daniela; Barbosa, Sérgio; Teixeira, Sérgio; Teixeira, Nuno; Torres, Rita T.; Travassos, Paulo; Vale‐Gonçalves, Hélia; Cidraes‐Vieira, Nuno; von Merten, Sophie; da Luz Mathias, Maria; Barreiro, Silvia; Barros, Paulo; Barros, Tânia; Barros, Filomena; Basto, Mafalda; Bernardino, Joana; Bicho, Sara; Biedma, Luis Eduardo; Borges, Marta; Braz, Luis; Brito, José Carlos; Brito, Tiago; Cabral, João Alexandre; Calzada, Javier; Camarinha, Cláudia; Carapuço, Mafalda; Cardoso, Paulo; Carmo, Mário; Carrapato, Carlos; da Silva Carrilho, Maílis; Carvalho, Diogo Filipe T. C. S.; Carvalho, Filipe; Carvalho, João; Castro, Diana; Castro, Guilherme; Castro, Joana; Castro, Luis Roma; Catry, Filipe Xavier; Cerveira, Ana M.; Cid, André; Clarke, Rafael; Conde, Conceição; Conde, José; Costa, Jorge; Costa, Mafalda; Costa, Pedro; Costa, Cristina; do Couto, André Pedro; Craveiro, João; Dias, Marta; Dias, Sofia; Duarte, Beatriz; Duro, Virginia; Encarnação, Cláudia; Eufrázio, Sofia; Fael, António; Falé, João Salvador; Faria, Sandra; Fernandes, Carlos; Fernandes, Margarida; da Costa, Gonçalo Ferrão; Ferreira, Clara; Ferreira, Diogo F.; Ferreira, Eduardo; Ferreira, Joaquim Pedro; Ferreira, João; Ferreira, Diana; Fonseca, Carlos; Fontes, Inês; Fragoso, Ricardo; Franco, Claudia; Freitas, Tamira; Gabriel, Sofia I.; Gibb, Rory; Gil, Patricia; Gomes, Carla Patricia Jorge; Horta, Pedro; Gomes, Pedro; Gomes, Verónica; Grilo, Filipa; Guedes, Américo; Guilherme, Filipa; Gutiérrez, Iván; Harper, Henry; Herrera, José M.; Hipólito, Dário; Infante, Samuel; Jesus, José
    Mammals are threatened worldwide, with 26% of all species being included in the IUCN threatened categories. This overall pattern is primarily associated with habitat loss or degradation, and human persecution for terrestrial mam mals, and pollution, open net fishing, climate change, and prey depletion for marine mammals. Mammals play a key role in maintaining ecosystems func tionality and resilience, and therefore information on their distribution is cru cial to delineate and support conservation actions. MAMMALS IN PORTUGAL is a publicly available data set compiling unpublished georeferenced occurrence records of 92 terrestrial, volant, and marine mam mals in mainland Portugal and archipelagos of the Azores and Madeira that includes 105,026 data entries between 1873 and 2021 (72% of the data occur ring in 2000 and 2021). The methods used to collect the data were: live obser vations/captures (43%), sign surveys (35%), camera trapping (16%), bioacoustics surveys (4%) and radiotracking, and inquiries that represent less than 1% of the records. The data set includes 13 types of records: (1) burrows j soil mounds j tunnel, (2) capture, (3) colony, (4) dead animal j hair j skulls j jaws, (5) genetic confirmation, (6) inquiries, (7) observation of live animal (8), observation in shelters, (9) photo trapping j video, (10) predators diet j pellets j pine cones/nuts, (11) scat j track j ditch, (12) telemetry and (13) vocalization j echolocation. The spatial uncertainty of most records ranges between 0 and 100 m (76%). Rodentia (n =31,573) has the highest number of records followed by Chiroptera (n = 18,857), Carnivora (n = 18,594), Lagomorpha (n = 17,496), Cetartiodactyla (n = 11,568) and Eulipotyphla (n = 7008). The data set includes records of species classified by the IUCN as threatened (e.g., Oryctolagus cuniculus [n = 12,159], Monachus monachus [n = 1,512], and Lynx pardinus [n = 197]). We believe that this data set may stimulate the publication of other European countries data sets that would certainly contrib ute to ecology and conservation-related research, and therefore assisting on the development of more accurate and tailored conservation management strategies for each species. There are no copyright restrictions; please cite this data paper when the data are used in publications.
    2022Journal article Open access Show more
  • Social calls are subject to stabilizing selection in insular bats
    Publication . Russo, Danilo; Teixeira, Sérgio; Cistrone, Luca; Jesus, José; Teixeira, David; Freitas, Tamira; Jones, Gareth
    Aim Bats communicate by emitting social calls, and these often elicit reactions in conspecifics. Many such vocalizations are species-specific so that unambiguous signals can be transmitted and interpreted by conspecifics. In species-rich assemblages, evolutionary pressures might prompt interspecific diversification of call structure so that communication with heterospecifics is avoided. In species poor island communities, where no risk of miscommunication occurs, stabilizing selection should prevail and preserve call structure and function. Call structure in island bats might be inherited from colonizers from the mainland and be maintained with little change in the absence of selection from heterospecifics. To test this hypothesis we studied Pipistrellus maderensis, an insular taxon occurring on the Madeira Archipelago, the Canary Islands and the Azores. It is closely related to one of the most widespread European pipistrelles, Pipistrellus kuhlii. Pipistrellus maderensis most probably evolved from a common ancestor shared with P. kuhlii, or from founders of that taxon that colonized the islands. We hypothesized that on Madeira Island, where no risk of ambiguous communication with heterospecifics exists, the structure and function of social calls should have been preserved by stabilizing selection. Echolocation calls, subject to different selection pressures, may instead show more pronounced differences between P. maderensis and P. kuhlii. Location Madeira Island (Portugal, Atlantic Ocean), central and southern Italy. Methods We recorded social and echolocation calls from allopatric populations of the two pipistrelles and explored interspecific differences in time and frequency characteristics. We also conducted playback experiments by broadcasting recordings of social calls from P. kuhlii and P. maderensis (taken respectively in peninsular Italy and on Madeira) and monitoring the bats’ responses. Results Social call structure showed a strong similarity between species, whereas echolocation calls were markedly different and exhibited a mean divergence of over 6 kHz in their frequency of maximum energy. On Madeira, P. maderensis significantly reduced flight activity when we broadcast P. kuhlii signals, as did P. kuhlii in Italy in response to P. maderensis calls. Main conclusions Reliable interpretation of social calls provides benefits to both the signaller and the receiver because signals help to optimize food exploitation at foraging sites. In the absence of closely related species that can emit similar calls, this advantage may have acted as a strong evolutionary pressure, stabilizing social call structure in P. maderensis in insular ecosystems with limited foraging resources.
    2009Journal article Open access Show more