title: Visual discrimination and object/picture recognition in hens

authors: Railton, Renee Caron Richards

subjects: hens

abstract: Eight experiments were conducted to examine different aspects of hen’s visual behaviour, and to assess whether hens responded to photographs in the same way they do to the real objects that were depicted in the photographs. In Experiment 1, six hens were trained to perform either a conditional discrimination (successive) or forced-choice discrimination (simultaneous) between flickering (25 Hz) and steady lights. A descending method of limits procedure was then used to increase the flicker speed by 5 Hz over blocks of 20 trials until percentages correct decreased below 55%. The critical flicker fusion frequency of hens was found to range between 68.5 and 95.4 Hz (at a luminance of 300 cd/m2). In Experiment 2, hens were trained to discriminate between steady images presented on a TFT screen, and tested for transfer of that discrimination to a CRT monitor at different refresh rates, on which the images were assumed to appear flickering. It was found that hens showed transfer across all refresh rates with coloured stimuli, but that the degree of transfer decreased as refresh rate decreased with stimuli that were discriminable only on shape. In Experiment 3, a similar decrease in accuracy was shown as refresh rate decreased using a range of stimuli. However, hens did not learn to discriminate all stimuli, and thus transfer could not be assessed with some stimuli. Experiment 4, hens were trained with flickering images and showed relatively high transfer to less flickering, or steady, images. In Experiment 5, a procedure was developed to assess whether hens transferred a discrimination of 3D object to 2D photographs of those objects, and vice versa. In Experiment 6, hens were trained to discriminate stimuli of different colours, or of different shapes. The hens learned to discriminate, and transferred this discrimination, with the coloured shapes. The hens also learned to discriminate the same colour (but differently shaped) stimuli, however, further testing showed that an extraneous variables had come to control behaviour. As a result, the equipment was modified for Experiments 7 and 8. In both experiments, only three of the six hens showed discrimination to any degree, and none transferred this discrimination to photographs or objects. It was concluded that hens do not respond to objects depicted in pictures in the same way they do to the real objects. Thus, these experiments show that that animals’ visual systems need to taken into account when visual stimuli are used in research, and researchers first need to establish that animals can see the visual stimuli and that the method of stimulus presentation is species appropriate if images are to be used as representatives of real world stimuli.

text: Visual discrimination and object/picture recognition in hens Eight experiments were conducted to examine different aspects of hen’s visual behaviour, and to assess whether hens responded to photographs in the same way they do to the real objects that were depicted in the photographs. In Experiment 1, six hens were trained to perform either a conditional discrimination (successive) or forced-choice discrimination (simultaneous) between flickering (25 Hz) and steady lights. A descending method of limits procedure was then used to increase the flicker speed by 5 Hz over blocks of 20 trials until percentages correct decreased below 55%. The critical flicker fusion frequency of hens was found to range between 68.5 and 95.4 Hz (at a luminance of 300 cd/m2). In Experiment 2, hens were trained to discriminate between steady images presented on a TFT screen, and tested for transfer of that discrimination to a CRT monitor at different refresh rates, on which the images were assumed to appear flickering. It was found that hens showed transfer across all refresh rates with coloured stimuli, but that the degree of transfer decreased as refresh rate decreased with stimuli that were discriminable only on shape. In Experiment 3, a similar decrease in accuracy was shown as refresh rate decreased using a range of stimuli. However, hens did not learn to discriminate all stimuli, and thus transfer could not be assessed with some stimuli. Experiment 4, hens were trained with flickering images and showed relatively high transfer to less flickering, or steady, images. In Experiment 5, a procedure was developed to assess whether hens transferred a discrimination of 3D object to 2D photographs of those objects, and vice versa. In Experiment 6, hens were trained to discriminate stimuli of different colours, or of different shapes. The hens learned to discriminate, and transferred this discrimination, with the coloured shapes. The hens also learned to discriminate the same colour (but differently shaped) stimuli, however, further testing showed that an extraneous variables had come to control behaviour. As a result, the equipment was modified for Experiments 7 and 8. In both experiments, only three of the six hens showed discrimination to any degree, and none transferred this discrimination to photographs or objects. It was concluded that hens do not respond to objects depicted in pictures in the same way they do to the real objects. Thus, these experiments show that that animals’ visual systems need to taken into account when visual stimuli are used in research, and researchers first need to establish that animals can see the visual stimuli and that the method of stimulus presentation is species appropriate if images are to be used as representatives of real world stimuli.

year: 2011

title: Bôcher contractions of conformally superintegrable Laplace equations

authors: Kalnins, Ernie G.

abstract: The explicit solvability of quantum superintegrable systems is due to symmetry, but the symmetry is often “hidden”. The symmetry generators of 2nd order superintegrable systems in 2 dimensions close under commutation to define quadratic algebras, a generalization of Lie algebras. Distinct systems on constant curvature spaces are related by geometric limits, induced by generalized Inönü–Wigner Lie algebra contractions of the symmetry algebras of the underlying spaces. These have physical/geometric implications, such as the Askey scheme for hypergeometric orthogonal polynomials. However, the limits have no satisfactory Lie algebra contraction interpretations for underlying spaces with 1- or 0-dimensional Lie algebras. We show that these systems can be best understood by transforming them to Laplace conformally superintegrable systems, with flat space conformal symmetry group SO(4, ℂ), and using ideas introduced in the 1894 thesis of Bôcher to study separable solutions of the wave equation in terms of roots of quadratic forms. We show that Bôcher’s prescription for coalescing roots of these forms induces contractions of the conformal algebra so(4, ℂ) to itself and yields a mechanism for classifying all Helmholtz superintegrable systems and their limits. In the paperActa Polytechnica, to appear, arXiv:1510.09067], we announced our main findings. This paper provides the proofs and more details.

text: Bôcher contractions of conformally superintegrable Laplace equations The explicit solvability of quantum superintegrable systems is due to symmetry, but the symmetry is often “hidden”. The symmetry generators of 2nd order superintegrable systems in 2 dimensions close under commutation to define quadratic algebras, a generalization of Lie algebras. Distinct systems on constant curvature spaces are related by geometric limits, induced by generalized Inönü–Wigner Lie algebra contractions of the symmetry algebras of the underlying spaces. These have physical/geometric implications, such as the Askey scheme for hypergeometric orthogonal polynomials. However, the limits have no satisfactory Lie algebra contraction interpretations for underlying spaces with 1- or 0-dimensional Lie algebras. We show that these systems can be best understood by transforming them to Laplace conformally superintegrable systems, with flat space conformal symmetry group SO(4, ℂ), and using ideas introduced in the 1894 thesis of Bôcher to study separable solutions of the wave equation in terms of roots of quadratic forms. We show that Bôcher’s prescription for coalescing roots of these forms induces contractions of the conformal algebra so(4, ℂ) to itself and yields a mechanism for classifying all Helmholtz superintegrable systems and their limits. In the paperActa Polytechnica, to appear, arXiv:1510.09067], we announced our main findings. This paper provides the proofs and more details.

year: 2016

title: From the rākau to the ngākau

authors: Derby, Melissa

subjects: research

abstract: The Ministry of Business, Innovation and Employment (MBIE) in Aotearoa New Zealand has funded 11 National Science Challenges (NSC), which aim to tackle a series of big questions affecting wellbeing in society. One Challenge, A Better Start: E Tipu E Rea, is investigating four key focus areas that children encounter in their early development and is seeking to identify the factors that contribute to forming a solid foundation for fostering wellbeing and lifelong success. Central to the principles of this Challenge is the Treaty of Waitangi in that the Treaty provides a framework to guide whānau engagement, policy change, and praxis. This article describes how a ‘ngākau’ rather than a ‘rākau’ approach to shaping research inquiry within this Challenge facilitates more authentic and mana-enhancing whānau engagement in research interactions (Macfarlane, 2019). The development of a whānau questionnaire is drawn on to illustrate the ngākau approach in practice.

text: From the rākau to the ngākau The Ministry of Business, Innovation and Employment (MBIE) in Aotearoa New Zealand has funded 11 National Science Challenges (NSC), which aim to tackle a series of big questions affecting wellbeing in society. One Challenge, A Better Start: E Tipu E Rea, is investigating four key focus areas that children encounter in their early development and is seeking to identify the factors that contribute to forming a solid foundation for fostering wellbeing and lifelong success. Central to the principles of this Challenge is the Treaty of Waitangi in that the Treaty provides a framework to guide whānau engagement, policy change, and praxis. This article describes how a ‘ngākau’ rather than a ‘rākau’ approach to shaping research inquiry within this Challenge facilitates more authentic and mana-enhancing whānau engagement in research interactions (Macfarlane, 2019). The development of a whānau questionnaire is drawn on to illustrate the ngākau approach in practice.

year: 2021