Aspectos evolutivos do splicing alternativo

The eukaryotes present intricate mechanisms to control gene expression, as alternative splicing. This mechanism is abundant in these organisms and permits the prodution of different proteins from a single percursor. This revision intends to show how alternative splicing can be an interesting tool in studies of evolution, comprising how the mechanism appeared and how it acts in the diversification of organisms.Os eucariotos apresentam mecanismos muito refinados para o controle de sua expressão gênica, dentre eles, o splicing alternativo. Este mecanismo, abundante entre estes organismos, possibilita a geração de diferentes proteínas a partir de um único gene. Esta revisão pretende mostrar como as características do splicing alternativo podem torná-lo uma ferramenta interessante em estudos com enfoque evolutivo, em questões envolvendo tanto o surgimento do mecanismo quanto sua atuação na diversificação dos seres vivos

Morphology and vocalization support specific status of the Chestnut-headed Chachalaca, Ortalis motmot ruficeps (Wagler, 1830) (Aves; Galliformes; Cracidae)

The Little Chachalaca (Ortalis motmot) is a widely distributed species in the Amazon basin, typically found in riverine habitats. There are two disjunct populations: the northern O. m. motmot and the southern O. m. ruficeps (known as Chestnut-headed Chachalaca). Here we performed a vocal, morphological and plumage comparison between these two taxa. Birds present differences in tail coloration but are otherwise undiagnosable in terms of plumage. Ortalis m. ruficeps is, however, markedly smaller and lighter than O. m. motmot, with no overlap in size or weight. We also found vocal differences between O. m. motmot and O. m. ruficeps, no overlap in geographic distributions and no signs of hybridization across its range. Based on the available data, Ortalis m. ruficeps thus must be considered a valid species, endemic to Brazil

Publication practice in Taxonomy: Global inequalities and potential bias against negative results

There is broad recognition by practicing taxonomists that the field is going through a crisis, which has been dubbed the “taxonomic impediment”. There are many aspects involved in said crisis, but publication practices in taxonomy are often neglected or relegated to the backseat. We provide an initial foray into this topic via a worldwide survey with taxonomists, spanning all botanical and zoological groups, and career stages. Demographically, most of the respondents identified themselves as males (70%), working in Europe or North America (68%), in universities (50%) or museums (27%). Over half of the respondents are established/late-career researchers (only about 25% of full professors were female), with a low number of early-career researchers and graduate students (i.e., taxonomists in training). Nearly 61% of the men acquired their highest title at least eleven years ago, while only 41% of the women did so. Nearly 92% of the respondents have published new species descriptions, while around 60% and 26% have synonymized, respectively, species-level or subspecies-level taxa. In general, respondents perceive the act of describing new species to be easier than synonymizing species (p = 0.05). Established/late-career researchers and male researchers, particularly in Oceania and North America, found it easier to publish nomenclatural acts such as new species descriptions, while early-career researchers had their acts contested more often. Our results reaffirm the low academic recognition of the field, the lack of funding for research and publishing charges especially in the Global South, and the difficulty in finding specialized outlets (and the low impact factor of those journals) as persistent issues in taxonomy. Other significant problems raised by respondents include ethical issues in the peer-review process, a bias against newcomers in the field coming either from established researchers or committees, and taxonomic vandalism

The rarest of the rare: rediscovery and status of the critically endangered Belem Curassow, Crax fasciolata pinima (Pelzeln, 1870)

The Belem Curassow (Crax fasciolata pinima) is one of the most endangered birds in South America, without sightings of birds in the wild for 40 years. This subspecies is nationally and internationally classified as critically endangered and close to extinction, suffering from poaching and deforestation in its range. Here we present new records of free-living individuals made on three indigenous lands in Pará and Maranhão states: in part of Terra Indígena Mãe Maria, Bom Jesus do Tocantins, Pará; in locations within the Reserva Biológica do Gurupi/Terra Indígena Alto Turiaçu, Centro Novo do Maranhão, Maranhão; and around the Terra Indígena Rio Pindaré, Alto Alegre do Pindaré, Maranhão. We also provide recommendations to protect this bird via a dedicated conservation program which includes finding new individuals in non-sampled areas (north of BR-222), estimating population size, enhancing taxonomic and natural history knowledge, capturing wild animals in order to start urgent ex situ conservation programs, and developing environmental awareness programs with the local and indigenous populations

Aftereffects of field entrainment and the activity phase of the subterranean rodent tuco-tuco (Rodentia: Ctenomyidae)

Os tuco-tucos de Anillaco (Ctenomys cf. knighti) são roedores subterrâneos noturnos quando colocados em ciclo claro-escuro no laboratório. Com o interesse de se investigar o quanto um animal subterrâneo se expõe à luz, foi realizado um experimento de observação contínua em campo durante as horas claras do dia. Três indivíduos, um em cada estação, foram observados em uma arena semi-natural. Essas observações revelaram que os tuco-tucos não apenas saíam freqüentemente durante as horas claras do dia, como também apresentavam atividades robustas de forrageamento e remoção de terra de seus túneis. Uma vez que não se tinha conhecimento da atividade abaixo da terra ou durante à noite, foram examinados os pós-efeitos do arrastamento em campo para se investigar se o ritmo estaria sincronizado em campo e o quanto da atividade observada correspondia à atividade total do animal. Os pós-efeitos foram acessados pela transferência dos animais observados diretamente da arena para condições constantes. Surpreendentemente os animais exibiram uma atividade robusta concentrada na fase correspondente à noite ambiental sem transientes e sem traços da atividade diurna previamente observada em campo. Esse padrão foi observado em outros 10 animais trazidos dessa vez diretamente do campo e colocados em condições constantes. Além disso, não foram observadas diferenças na fase de atividade de animais com e sem acesso a rodas de atividade. Portando, nosso estudo com esses animais subterrâneos pode contribuir com elementos ecológicos nas discussões recentes sobre o significado da atividade diurna em animais que são noturnos segundo a fase do osciladorSouth American subterranean rodents (Ctenomys cf. knighti), commonly known as tuco-tucos, display robust, nocturnal, wheel-running rhythms under a light-dark condition. To verify whether these subterranean and nocturnal animals ever expose themselves to light in the field, individual animals were continuously observed during light hours in a semi-natural enclosure that was constructed in their natural habitat. Observations during different seasons revealed that tuco-tucos not only emerged aboveground during daylight hours but also that their light exposure was due to robust diurnal activities of foraging and soil removal. Because of the lack of access to these animals´ subterranean and nocturnal activities in the field, the aftereffects of field entrainment were examined instead to verify the contribution of the previously observed diurnal behaviors to the total daily activity. This examination was achieved by transferring the observed animals from a field enclosure to constant laboratory conditions. Surprisingly, tuco-tucos exhibited robust activity concentrated in the phase corresponding to the external night without any trace of transients or of the diurnal activity that was observed in the enclosure. This pattern was also replicated when the aftereffects of the field entrainment of other animals trapped directly from the field were measured in the laboratory. Furthermore, no difference was detected in the activity measured with and without access to a running wheel. Our study of a wild subterranean species in its natural habitat can contribute novel ecological elements to the recently debated issue of the meaning of day-activity displayed by nocturnal rodents in the fiel

Database S1

Body, tail and wingbeat kinematics for all analyzed flight sequences, stored in MATLAB (MathWorks, Inc.) binary data container format. Each flight sequence is identified by the combination calendar date and sequence number; treatment information consists of treatment group (‘control’ or ‘molt’), bird ID number and frames per second of the video. The movement dynamics of each digitized body, wing and tail marker throughout the flight is defined as its {x,y,z} position throughout time (t) and normalized time (tau). See Figure 1A for the {x,y,z} coordinate system, and Figure 1C and Table 1 for the definition of the natural body, wing and tail markers

Data from: A songbird compensates for wing molt during escape flights by reducing the molt gap and increasing angle-of-attack

During molt, birds replace their feathers to retain feather quality and maintain flight performance. However, wing gaps inherent of this process can also reduce flight capacities, which could be detrimental when foraging or escaping predators. Still, many bird species will not stop their normal activities when molting. In this study, we investigated whether and how birds adjust their escape flight behavior to compensate for the reduction in performance when flying with wing gaps. Using stereoscopic high-speed videography, we filmed 146 upward-directed escape flights of 19 and 22 pied flycatchers (Ficedula hypoleuca) with and without simulated molt gaps, respectively. We then reconstructed the three-dimensional body and wing movements throughout each maneuver. By comparing flights with and without gaps, we determined how wing molt gaps affected wing morphology, escape flight performance, and how the birds adjusted their flight kinematics in order to negate possible negative aerodynamic effects. Our manipulations resulted in a lower second-moment-of-area of the wings, but flight speed and net aerodynamic force production did not differ between the two groups. We found that in manipulated birds, the size of the gap was reduced as the flight feathers adjacent to the gap had moved towards each other. Moreover, the experimental decrease in second-moment-of-area was associated with an increase in angle-of-attack, whereas changes in wingbeat-induced speeds were associated with variations in aerodynamic force production. This suggests that the control of escape flight in molting birds might be modular, allowing relatively simple flight control, thus reducing the burden on the neuro-muscular flight control system

A new fossil species of kiwi (Aves: Apterygidae) from the mid-Pleistocene of New Zealand

We describe Apteryx littoralis sp. nov., a new species of kiwi based on a 1-million-year-old tarsometatarsus from shallow marine sediment in the North Island of New Zealand. The fossil is very similar to the tarsometatarsi of living kiwi species, most closely resembling Apteryx rowi and A. mantelli in size and shape, but differs in being stouter, with proportionally narrower proximal and distal ends. The new fossil is the second oldest known record of kiwi. It demonstrates a relatively conservative kiwi morphology since the mid-Pleistocene. http://zoobank.org/References/cefc907d-0c1d-44dc-83c5-5799f5d6d3d2