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1.
Front Psychiatry ; 15: 1325292, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38577401

RESUMEN

Adverse climatic changes around the globe and predictions of catastrophic and irreversible alteration in global weather patterns, temperature rise, and coast-line habitability require a careful examination of consequences on the resilience and mental health of people who will endure these changes. This paper is concerned with the South Pacific region. This geography has benefited from a relatively stable climate that is seen in the lush and vibrant natural world with many unique species of plants and animals exclusively found here. This paper examines the psychological profile of the people in the South Pacific using an evolutionary framework, and considers their local climate risks and lifestyle patterns with the aim of exploring possible mental health trajectories.

2.
Naturwissenschaften ; 100(7): 621-31, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23771705

RESUMEN

How do distinct visual stimuli help bumblebees discover flowers before they have experienced any reward outside of their nest? Two visual floral properties, type of a pattern (concentric vs radial) and its position on unrewarding artificial flowers (central vs peripheral on corolla), were manipulated in two experiments. Both visual properties showed significant effects on floral choice. When pitted against each other, pattern was more important than position. Experiment 1 shows a significant effect of concentric pattern position, and experiment 2 shows a significant preference towards radial patterns regardless of their position. These results show that the presence of markings at the center of a flower are not so important as the presence of markings that will direct bees there.


Asunto(s)
Abejas/fisiología , Conducta Animal/fisiología , Conducta de Elección/fisiología , Flores/anatomía & histología , Animales
3.
J Econ Entomol ; 105(1): 34-9, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22420252

RESUMEN

The foraging behavior of bumble bees (Bombus impatiens Cresson) was examined as a function of feeder location containing sugar solution in a commercial tomato greenhouse in Manotick, Ontario, Canada. The feeders were located within the nest-box (fed-close) or placed 1.5 m away (fed-far) and the placement of the two types of colonies was counterbalanced over time. No effect of feeder location was found in colony activity levels or in pollen load size. A foraging trade-off between sugar solution and pollen collection, however, was found: the proportion of foraging trips in which pollen was brought back was significantly reduced for fed-far colonies, which contrasts with our laboratory study in which the opposite effect was found. We interpret our findings as possibly reflecting a limitation in pollen supply in the greenhouse: an already possibly strained ability to find and bring back pollen to the colony was accentuated by increasing the task demands of collecting sugar solution.


Asunto(s)
Abejas/fisiología , Agricultura , Animales , Carbohidratos , Conducta Alimentaria , Femenino , Solanum lycopersicum/fisiología , Masculino , Ontario , Polen , Polinización
4.
PLoS One ; 10(7): e0132218, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26200767

RESUMEN

Untrained, "flower-naïve" bumblebees display behavioural preferences when presented with visual properties such as colour, symmetry, spatial frequency and others. Two unsupervised neural networks were implemented to understand the extent to which these models capture elements of bumblebees' unlearned visual preferences towards flower-like visual properties. The computational models, which are variants of Independent Component Analysis and Feature-Extracting Bidirectional Associative Memory, use images of test-patterns that are identical to ones used in behavioural studies. Each model works by decomposing images of floral patterns into meaningful underlying factors. We reconstruct the original floral image using the components and compare the quality of the reconstructed image to the original image. Independent Component Analysis matches behavioural results substantially better across several visual properties. These results are interpreted to support a hypothesis that the temporal and energetic costs of information processing by pollinators served as a selective pressure on floral displays: flowers adapted to pollinators' cognitive constraints.


Asunto(s)
Abejas/fisiología , Percepción Visual/fisiología , Animales , Redes Neurales de la Computación
5.
J Comp Psychol ; 129(3): 229-36, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25984936

RESUMEN

The behavioral experiment herein tests the computational load hypothesis generated by an unsupervised neural network to examine bumblebee (Bombus impatiens) behavior at 2 visual properties: spatial frequency and symmetry. Untrained "flower-naïve" bumblebees were hypothesized to prefer symmetry only when the spatial frequency of artificial flowers is high and therefore places great information-processing demands on the bumblebees' visual system. Bumblebee choice behavior was recorded using high-definition motion-sensitive camcorders. The results support the computational model's prediction: 1-axis symmetry influenced bumblebees' preference behavior at low and high spatial frequency patterns. Additionally, increasing the level of symmetry from 1 axis to 4 axes amplified preference toward the symmetric patterns of both low and high spatial frequency patterns. The results are discussed in the context of the artificial neural network model and other hypotheses generated from the behavioral literature.


Asunto(s)
Abejas/fisiología , Conducta Animal/fisiología , Conducta de Elección/fisiología , Redes Neurales de la Computación , Reconocimiento Visual de Modelos/fisiología , Animales
6.
J Vis Exp ; (93): e52033, 2014 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-25489677

RESUMEN

We present two methods for observing bumblebee choice behavior in an enclosed testing space. The first method consists of Radio Frequency Identification (RFID) readers built into artificial flowers that display various visual cues, and RFID tags (i.e., passive transponders) glued to the thorax of bumblebee workers. The novelty in our implementation is that RFID readers are built directly into artificial flowers that are capable of displaying several distinct visual properties such as color, pattern type, spatial frequency (i.e., "busyness" of the pattern), and symmetry (spatial frequency and symmetry were not manipulated in this experiment). Additionally, these visual displays in conjunction with the automated systems are capable of recording unrewarded and untrained choice behavior. The second method consists of recording choice behavior at artificial flowers using motion-sensitive high-definition camcorders. Bumblebees have number tags glued to their thoraces for unique identification. The advantage in this implementation over RFID is that in addition to observing landing behavior, alternate measures of preference such as hovering and antennation may also be observed. Both automation methods increase experimental control, and internal validity by allowing larger scale studies that take into account individual differences. External validity is also improved because bees can freely enter and exit the testing environment without constraints such as the availability of a research assistant on-site. Compared to human observation in real time, the automated methods are more cost-effective and possibly less error-prone.


Asunto(s)
Abejas/fisiología , Conducta de Elección/fisiología , Dispositivo de Identificación por Radiofrecuencia/métodos , Grabación en Video/métodos , Animales
7.
Evol Psychol ; 10(2): 238-52, 2012 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-22947637

RESUMEN

The present study explores two hypotheses: a) women during early pregnancy should experience increased color discrimination ability, and b) women during early pregnancy should experience shifts in subjective preference away from images of foods that appear either unripe or spoiled. Both of these hypotheses derive from an adaptive view of pregnancy sickness that proposes the function of pregnancy sickness is to decrease the likelihood of ingestion of foods with toxins or teratogens. Changes to color discrimination could be part of a network of perceptual and physiological defenses (e.g., changes to olfaction, nausea, vomiting) that support such a function. Participants included 13 pregnant women and 18 non-pregnant women. Pregnant women scored significantly higher than non-pregnant controls on the Farnsworth-Munsell (FM) 100 Hue Test, an objective test of color discrimination, although no difference was found between groups in preferences for food images at different stages of ripeness or spoilage. These results are the first indication that changes to color discrimination may occur during early pregnancy, and is consistent with the view that pregnancy sickness may function as an adaptive defense mechanism.


Asunto(s)
Percepción de Color/fisiología , Discriminación en Psicología , Alimentos , Náuseas Matinales/psicología , Primer Trimestre del Embarazo/psicología , Adulto , Estudios de Casos y Controles , Femenino , Humanos , Embarazo , Primer Trimestre del Embarazo/fisiología
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