367 research outputs found
Compound tool construction by New Caledonian crows
The construction of novel compound tools through assemblage of otherwise non-functional elements involves anticipation of the affordances of the tools to be built. Except for few observations in captive great apes, compound tool construction is unknown outside humans, and tool innovation appears late in human ontogeny. We report that habitually tool-using New Caledonian crows (Corvus moneduloides) can combine objects to construct novel compound tools. We presented 8 naive crows with combinable elements too short to retrieve food targets. Four crows spontaneously combined elements to make functional tools, and did so conditionally on the position of food. One of them made 3- and 4-piece tools when required. In humans, individual innovation in compound tool construction is often claimed to be evolutionarily and mechanistically related to planning, complex task coordination, executive control, and even language. Our results are not accountable by direct reinforcement learning but corroborate that these crows possess highly flexible abilities that allow them to solve novel problems rapidly. The underlying cognitive processes however remain opaque for now. They probably include the species' typical propensity to use tools, their ability to judge affordances that make some objects usable as tools, and an ability to innovate perhaps through virtual, cognitive simulations
Flexibility in Problem Solving and Tool Use of Kea and New Caledonian Crows in a Multi Access Box Paradigm
Parrots and corvids show outstanding innovative and flexible behaviour. In particular, kea and New Caledonian crows are often singled out as being exceptionally sophisticated in physical cognition, so that comparing them in this respect is particularly interesting. However, comparing cognitive mechanisms among species requires consideration of non-cognitive behavioural propensities and morphological characteristics evolved from different ancestry and adapted to fit different ecological niches. We used a novel experimental approach based on a Multi-Access-Box (MAB). Food could be extracted by four different techniques, two of them involving tools. Initially all four options were available to the subjects. Once they reached criterion for mastering one option, this task was blocked, until the subjects became proficient in another solution. The exploratory behaviour differed considerably. Only one (of six) kea and one (of five) NCC mastered all four options, including a first report of innovative stick tool use in kea. The crows were more efficient in using the stick tool, the kea the ball tool. The kea were haptically more explorative than the NCC, discovered two or three solutions within the first ten trials (against a mean of 0.75 discoveries by the crows) and switched more quickly to new solutions when the previous one was blocked. Differences in exploration technique, neophobia and object manipulation are likely to explain differential performance across the set of tasks. Our study further underlines the need to use a diversity of tasks when comparing cognitive traits between members of different species. Extension of a similar method to other taxa could help developing a comparative cognition research program
Innovative problem solving by wild falcons
Innovation (i.e., a new solution to a familiar problem, or applying an existing behavior to a novel problem1,2) plays a fundamental role in species’ ecology and evolution. It can be a useful measure for cross-group comparisons of behavioral and cognitive flexibility and a proxy for general intelligence.3,4,5 Among birds, experimental studies of innovation (and cognition more generally) are largely from captive corvids and parrots,6,7,8,9,10,11,12 though we lack serious models for avian technical intelligence outside these taxa. Striated caracaras (Phalcoboenus australis) are Falconiformes, sister clade to parrots and passerines,13,14,15 and those endemic to the Falkland Islands (Malvinas) show curiosity and neophilia similar to notoriously neophilic kea parrots16,17 and face similar socio-ecological pressures to corvids and parrots.18,19 We tested wild striated caracaras as a new avian model for technical cognition and innovation using a field-applicable 8-task comparative paradigm (adapted from Rössler et al.20 and Auersperg et al.21). The setup allowed us to assess behavior, rate, and flexibility of problem solving over repeated exposure in a natural setting. Like other generalist species with low neophobia,21,22 we predicted caracaras to demonstrate a haptic approach to solving tasks, flexibly switching to new, unsolved problems and improving their performance over time. Striated caracaras performed comparably to tool-using parrots,20 nearly reaching ceiling levels of innovation in few trials, repeatedly and flexibly solving tasks, and rapidly learning. We attribute our findings to the birds’ ecology, including geographic restriction, resource unpredictability, and opportunistic generalism,23,24,25 and encourage future work investigating their cognitive abilities in the wild.Fil: Harrington, Katie J.. Medical University Of Vienna; AustriaFil: Folkertsma, Remco. Medical University Of Vienna; AustriaFil: Auersperg, Alice M. I.. Medical University Of Vienna; AustriaFil: Biondi, Laura Marina. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Lambert, Megan L.. Medical University Of Vienna; Austri
Orangutans (Pongo abelii) make flexible decisions relative to reward quality and tool functionality in a multi-dimensional tool-use task
This work was supported by the University of St Andrews and the Max Planck Institute for Evolutionary Anthropology. Isabelle Laumer was supported by a uni:docs fellowship of the University of Vienna, Alice Auersperg was supported by by FWF grants J 3404-B19 and P 29084, and Thomas Bugnyar by Y366-B17.Making economic decisions in a natural foraging situation that involves the use of tools, may require an animal to consider more levels of relational complexity than merely deciding between an immediate and a delayed food option. We used the same method previously used with Goffin´s cockatoos to investigate the orangutans’ flexibility for making the most profitable decisions when confronted with five different settings that included one or two different apparatuses, two different tools and two food items (one more preferred than the other). We found that orangutans made profitable decisions relative to reward quality, when the task required the subjects to select a tool over an immediately accessible food reward. Furthermore, most subjects were sensitive to work-effort when the immediate and the delayed option (directly accessible by using a tool) led to the same outcome. Most subjects continued to make profitable decisions that required taking into account the tool functionality. In a final multidimensional task design in which subjects had to simultaneously focus on two apparatuses, two reward qualities and two different tools, the orangutans chose the functional tool to access the high quality reward.Publisher PDFPeer reviewe
Spontaneous innovation of hook-bending and unbending in orangutans (Pongo abelii)
This work was supported by FWF Grants P-29084 and P-29075 to Alice Auersperg and by a uni:docs fellowship of the University of Vienna to Isabelle Laumer.Betty the crow astonished the scientific world as she spontaneously crafted hook-tools from straight wire in order to lift a basket out of vertical tubes. Recently it was suggested that this species’ solution was strongly influenced by predispositions from behavioural routines from habitual hook-tool manufacture. Nevertheless, the task became a paradigm to investigate tool innovation. Considering that young humans had surprising difficulties with the task, it was yet unclear whether the innovation of a hooked tool would be feasible to primates that lacked habitual hook making. We thus tested five captive orangutans in a hook bending and unbending task. Orangutans are habitually tool-using primates that have been reported to use but not craft hooked tools for locomotion in the wild. Two orangutans spontaneously innovated hook tools and four unbent the wire from their first trial on. Pre-experience with ready-made hooks had some effect but did not lead to continuous success. Further subjects improved the hook-design feature when the task required the subjects to bent the hook at a steeper angle. Our results indicate that the ability to represent and manufacture tools according to a current need does not require stereotyped behavioural routines, but can indeed arise innovatively. Furthermore, the present study shows that the capacity for hook tool innovation is not limited to large brained birds within non-human animals.Publisher PDFPeer reviewe
CL100 expression is down-regulated in advanced epithelial ovarian cancer and its re-expression decreases its malignant potential
Although early stage ovarian cancer can be effectively treated with surgery and chemotherapy, the majority of cases present with advanced disease, which remains essentially incurable. Unfortunately, little is known about the genes important for the development and progression of this disease. In this study, the expression of 68 phosphatases was determined in immortalized ovarian epithelial cells (IOSE) and compared to ovarian cancer cell lines. CL100, a dual specificity phosphatase, displayed 10-25-fold higher expression in normal compared to malignant ovarian cell lines. Immunohistochemical staining of normal ovaries and 68 ovarian cancer specimens confirmed this differential expression. Re-expression of CL100 in ovarian cancer cells decreased adherent and non-adherent cell growth and induced phenotypic changes including loss of filopodia and lamellipodia with an associated decrease in cell motility. Induced expression of CL100 in ovarian cancer cells suppressed intraperitoneal tumor growth in nude mice. These results show for the first time that CL100 expression is altered in human ovarian cancer, that CL100 expression changes cell morphology and motility, and that it suppresses intraperitoneal growth of human ovarian epithelial cancer. These data suggest that down-regulation of CL100 may play a role in the progression of human ovarian cancer
Establishment of an immortalised human ovarian surface epithelial cell line without chromosomal instability
Epithelial ovarian carcinoma is thought to derive from ovarian surface epithelium (OSE). The black box of the early molecular changes in ovarian carcinogenesis is being interpreted by the development of experimental systems employing immortalised human OSE cells. However, the existing cell lines of the OSE cells have limited utility due to chromosomal instability. Our goal was to establish new immortalised human OSE cells that retain the original characteristics of the primary cells without chromosomal alterations. Using primary human OSE cells obtained from a postmenopausal patient with endometrial cancer, five cell lines (‘HOSE1' lines) were newly established by infection with retroviral expression vectors containing type 16 human papillomavirus (HPV-16) E6, E7, a variant E6 (E6Δ151), and Bmi1 polycomb gene, in combination with telomerase reverse transcriptase (hTERT). Consequently, five HOSE1s cell lines, HOSE1s-E6/hTERT, -E7/hTERT, -E6/E7/hTERT, -E6Δ151/E7/hTERT, and -E6Δ151/Bmi1/hTERT, grew beyond the population doubling number of 200. These cell lines, except for HOSE1-E6/hTERT, essentially showed the original features of the primary human OSE cells. Of them, HOSE1-E7/hTERT preserved diploidy in a kariotype analysis, and did not show transformed phenotypes in anchorage-independent growth and tumour formation. Thus, HOSE1-E7/hTERT may provide a novel model system with which to investigate the mechanisms of early molecular changes
MUC4 activates HER2 signalling and enhances the motility of human ovarian cancer cells
The mucin MUC4 is a high molecular weight transmembrane glycoprotein. It consists of a mucin-type subunit (MUC4α) and a transmembrane growth factor-like subunit (MUC4β). The mucin MUC4 is overexpressed in many epithelial malignancies including ovarian cancer, suggesting a possible role in the pathogenesis of these cancers. In this study, we investigated the functional role of MUC4 in the human ovarian cancer cell line SKOV3. The mucin MUC4 was ectopically expressed by stable transfection, and its expression was examined by western blot and confocal microscopy analyses. The in vitro studies demonstrated an enhanced motility of MUC4-expressing SKOV3 cells compared with the vector-transfected cells. The mucin MUC4 expression was associated with apparent changes in actin organisation, leading to the formation of microspike, lammelopodia and filopodia-like cellular projections. An enhanced protein expression and activation of HER2, a receptor tyrosine kinase, was also seen, although no significant change was observed in HER-2 transcript levels in the MUC4-transfected SKOV3 cells. Reciprocal co-immunoprecipitation revealed an interaction of MUC4 with HER2. Further, the MUC4-overexpressing SKOV3 cells exhibited an increase in the phosphorylation of focal adhesion kinase (FAK), Akt and ERK, downstream effectors of HER2. Taken together, our findings demonstrate that MUC4 plays a role in ovarian cancer cell motility, in part, by altering actin arrangement and potentiating HER2 downstream signalling in these cells
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