22 research outputs found

    Imitation of novel conspecific and human speech sounds in the killer whale (Orcinus orca)

    Get PDF
    This project was conducted at the Marineland Aquarium Antibes, France and supported by a Postdoctoral Scholarship FONDECYT Nº 3140580 to J.Z. Abramson. This study was partly funded by project grants PSI2011-29016-C02-01, PSI2014-51890-C2-1-P (MINECO, Spain) and UCM-BSCH GR3/14-940813 (Universidad Complutense de Madrid y Banco Santander Central Hispano) to F. Colmenares.Vocal imitation is a hallmark of human spoken language, which, along with other advanced cognitive skills, has fuelled the evolution of human culture. Comparative evidence has revealed that although the ability to copy sounds from conspecifics is mostly uniquely human among primates, a few distantly related taxa of birds and mammals have also independently evolved this capacity. Remarkably, field observations of killer whales have documented the existence of group-differentiated vocal dialects that are often referred to as traditions or cultures and are hypothesized to be acquired non-genetically. Here we use a -Do as I do- paradigm to study the abilities of a killer whale to imitate novel sounds uttered by conspecific (vocal imitative learning) and human models (vocal mimicry). We found that the subject made recognizable copies of all familiar and novel conspecific and human sounds tested and did so relatively quickly (most during the first 10 trials and three in the first attempt). Our results lend support to the hypothesis that the vocal variants observed in natural populations of this species can be socially learned by imitation. The capacity for vocal imitation shown in this study may scaffold the natural vocal traditions of killer whales in the wild.PostprintPeer reviewe

    Hypoxia Negatively Regulates Antimetastatic PEDF in Melanoma Cells by a Hypoxia Inducible Factor-Independent, Autophagy Dependent Mechanism

    Get PDF
    Pigment epithelium-derived factor (PEDF), a member of the serine protease inhibitor (SERPIN) superfamily, displays a potent antiangiogenic and antimetastatic activity in a broad range of tumor types. Melanocytes and low aggressive melanoma cells secrete high levels of PEDF, while its expression is lost in highly aggressive melanomas. PEDF efficiently abrogates a number of functional properties critical for the acquisition of metastatic ability by melanoma cells, such as neovascularization, proliferation, migration, invasiveness and extravasation. In this study, we identify hypoxia as a relevant negative regulator of PEDF in melanocytes and low aggressive melanoma cells. PEDF was regulated at the protein level. Importantly, although downregulation of PEDF was induced by inhibition of 2-oxoglutarate-dependent dioxygenases, it was independent of the hypoxia inducible factor (HIF), a key mediator of the adaptation to hypoxia. Decreased PEDF protein was not mediated by inhibition of translation through untranslated regions (UTRs) in melanoma cells. Degradation by metalloproteinases, implicated on PEDF degradation in retinal pigment epithelial cells, or by the proteasome, was also excluded as regulatory mechanism in melanoma cells. Instead, we found that degradation by autophagy was critical for PEDF downregulation under hypoxia in human melanoma cells. Our findings show that hypoxic conditions encountered during primary melanoma growth downregulate antiangiogenic and antimetastasic PEDF by a posttranslational mechanism involving degradation by autophagy and could therefore contribute to the acquisition of highly metastatic potential characteristic of aggressive melanoma cells

    ALLEVAMENTO DI BESTIAME BOVINO IN ITALIA

    Get PDF
    The research reported in this paper was partly funded by project grants PSI2011-29016-C02-01, PSI2014-51890-C2-1-P (Ministerio de Economía y Competitividad, Spain) http://www.mineco.gob.es/ and UCM-BSCH GR3/14-940813 (Universidad Complutense de Madrid y Banco Santander Central Hispano) to F. C. A post-doctoral scholarship from Fondo Nacional de Desarrollo Científico y Tecnológico / FONDECYT Nº 3140580 awarded to J.ZA. funded his salary. http://www.conicyt.cl/fondecyt. European Research Council under the European Union's Seventh Framework Programme (FP7/2007-2013) / ERC grant SOMICS agreement n° 609819. Dr. Josep Call.Cetaceans are remarkable for exhibiting group-specific behavioral traditions or cultures in several behavioral domains (e.g., calls, behavioral tactics), and the question of whether they can be acquired socially, for example through imitative processes, remains open. Here we used a “Do as other does” paradigm to experimentally study the ability of a beluga to imitate familiar intransitive (body-oriented) actions demonstrated by a conspecific. The participant was first trained to copy three familiar behaviors on command (training phase) and then was tested for her ability to generalize the learned “Do as the other does” command to a different set of three familiar behaviors (testing phase). We found that the beluga (1) was capable of learning the copy command signal “Do what-the-other-does”; (2) exhibited high matching accuracy for trained behaviors (mean = 84% of correct performance) after making the first successful copy on command; (3) copied successfully the new set of three familiar generalization behaviors that were untrained to the copy command (range of first copy = 12 to 35 trials); and (4) deployed a high level of matching accuracy (mean = 83%) after making the first copy of an untrained behavior on command. This is the first evidence of contextual imitation of intransitive (body-oriented) movements in the beluga and adds to the reported findings on production imitation of sounds in this species and production imitation of sounds and motor actions in several cetaceans, especially dolphins and killer whales. Collectively these findings highlight the notion that cetaceans have a natural propensity at skillfully and proficiently matching the sounds and body movements demonstrated by conspecifics, a fitness-enhancing propensity in the context of cooperative hunting and anti-predatory defense tactics, and of alliance formation strategies that have been documented in these species’ natural habitats. Future work should determine if the beluga can also imitate novel motor actions.Publisher PDFPeer reviewe

    NEW RECORDS OF BLUE WHALES BALAENOPTERA MUSCULUS (LINNAEUS, 1758) IN WINTER SEASON IN THE INLET WATERS OF CHILOÉ CONTINENTAL-CHILE

    No full text

    Experimental set up.

    No full text
    <p>Two trainers (T<sub>D</sub> and T<sub>S;</sub> D for demonstrator and S for subject), were positioned on different sides of an opaque panel 2m long x 91cm high placed in a position in which S and D could see each other and their own trainer, but could not see the other trainer’s commands.</p
    corecore