Scratch Rate Research Articles

The maternal feeding display of domestic hens is sensitive to perceived chick error

An animal can be said to teach if, at some cost or at least without obtaining an immediate benefit for itself, it modifies its behaviour in the presence of a naı̈ve observer, such that the observer acquires a skill more efficiently than it might otherwise do. An important theoretical issue is the extent to which the demonstrator's behaviour is sensitive to the improving skill level of the observer. This study determined whether domestic hens, Gallus gallus domesticus, were sensitive to feeding errors by their chicks. The feeding displays of 12 hens were studied in two contexts: (1) in the presence of chicks that fed on a food colour that was palatable to the hen, and hence made no apparent feeding errors and (2) in the presence of chicks that fed on a food colour that was unpalatable to the hen, and hence made apparent feeding errors. Both groups of chicks, in reality, fed on palatable food. Hens responded more intensely to chicks that made apparent feeding errors. Hens increased the rate of ground pecking and scratching when they had no food available, and increased the rate of food pecking (although not food ingestion) when they were given food. It is suggested that hens are sensitive to perceived chick error, and that the costs of increased display intensity are balanced by the benefits of attracting chicks to more profitable food items.

Discrimination learning of scratching, but failure to obtain imitation and self-recognition in a long-tailed macaque

A long-tailed macaque was trained to scratch when a model scratched, but failed to generalize scratching when model scratched new target areas. The results confirm that monkeys can control their rates of scratching, but may not be capable of true imitation. The subject also failed on a test of mirror self-recognition. Imitation and self-recognition appear to be related capacities, which may be absent in monkeys.

Maternal Anxiety in Rhesus Macaques (Macaca mulatta)

AbstractVisual monitoring and scratching were used as behavioral indicators of maternal and social anxiety in small captive groups of rhesus macaques. Young infants were especially at risk from other group members during the first weeks of locomotion away from their mothers. Mothers received aggression from other individuals irrespective of their infants' presence or absence. The rate at which mothers scratched themselves increased significantly when their infants moved away from them and when the infants approached or were approached by individuals who frequently harassed them. The rate of maternal scratching and the rate of glancing at the infant and at other individuals when the infant was away decreased as infants grew older and became less vulnerable to harassment. In contrast, the rate of maternal scratching and visual monitoring of other individuals when the infant was in contact remained stable across the first 12 wk of lactation. The rate of maternal scratching increased when the mother‐infant pair was in spatial proximity to the adult male or higher ranking adult females. Although visual monitoring and scratching showed a similar sensitivity to social variables, it is speculated that they might reflect different components of anxiety, namely, anticipation of danger and uncertainty due to motivational conflict. The results of this investigation indicate that a macaque mother's emotional reactivity to a perceived danger for herself and her infant can be measured quite accurately using the rates of visual monitoring and scratching and that the latter represent reliable tools to investigate the emotional correlates of maternal behavior in nonhuman primates.

Post‐conflict Behaviour in Long‐tailed Macaques (Macaca fascicularis)

AbstractAfter being the victim of an agonistic conflict, long‐tailed macaques increased the rate of tension‐related activities such as scratching, body‐shake and selfgrooming. This increase indicates that they experienced physiological changes preparing them to cope with the uncertainty of the post‐conflict situation. Indeed, victims of agonistic conflict experienced a higher risk of renewed attacks. However, victims were also involved in social interactions characteristic of post‐conflict situations, namely reconciliation and redirection. These two post‐conflict social events reduced the rate of scratching, body‐shake and selfgrooming. This suggests a faster termination of the stress response. Indeed, the two social events also decreased the likelihood of renewed attacks, one of the causes of the state of uncertainty. Reconciliation is more effective than redirection in this process probably because the restoration of the relationship with the former aggressor allows the victim to resume control of the situation.

Operant conditioning of scratching in lemurs

An adult femaleLemur catta and an adult femaleEulemur fulvus were given edible rewards for scratching. Both subjects learned to scratch in order to obtain the rewards, showed diminished rates of scratching during periods of extinction, and learned to scratch preferentially with one foot when required. TheLemur catta subject was more responsive to the changing experimental conditions than theEulemur fulvus. The conditionability of scratching in primates does not appear to be directly related to the widespread occurrence of scratching in simian social contexts.

Scratching, dominance, tension, and displacement in male baboons.

This paper reports a study designed to test the hypothesis that a relationship exists among dominance rank, tension, and scratch behaviors in anubis baboons (Papio cynocephalus anubis). Our study was conducted on two groups of male baboons, each containing eight unrelated individuals who were approximately 6 years of age and who shared common rearing histories. Focal animal sampling was used to collect behavioral data. Hand scratching, foot scratching, avoid, tension, allogrooming, autogrooming, and manipulation were measured as acts performed per hour of sampling. Dominance matrices were constructed based on net difference of avoid behavior performed and received (adjusted for time sampled). Individual status ranks were grouped into two status classes, high and low. Analysis of variance models demonstrated significant differences in the performance rate of scratching behaviors by dominance rank class, as well as differences in scratching performance by tension class. Individuals in the high status class had significantly higher rates of total scratching, hand scratching, foot scratching, and tension behavior performance than their counterparts in the low status class. No significant difference was found between status classes or tension classes for performance rate of allogrooming, autogrooming, or manipulation behavior. The frequency of scratching and general level of activity were not significantly correlated. The results are interpreted to indicate the possibility that scratching may function as a displacement behavior, which subjectively appears to communicate heightened frustration, anxiety, or arousal.

Instrumental conditioning of scratching in the laboratory rat

Experiment 1 demonstrates that scratching in the laboratory rat can be instrumentally conditioned with food reinforcement. However, the asymptotic rate of performance of this response is shown to be low, as compared with an instrumental lever press response. It is suggested that one reason for this low rate of responding is that the scratch response can only be performed in the presence of an infrequently occurring itch stimulus. In support of this account the remaining experiments demonstrate that the rate of instrumental scratching can be increased relative to that shown by control groups by using a technique which might be supposed to increase the frequency at which an itch stimulus occurs.

The house building behaviour of the caddis-fly larva Silo pallipes fabricius: II. Description and analysis of the selection of small particles

1. 1. The activities used by larvae to locate, test and fit particles to the house, are described. They are: silk chewing, walking, circling, scratch test, handle test, and fit test. 2. 2. Loose particles are necessary to initiate the scratch test but the number of particles does not influence the rate of scratching or handling, or the rate or type of locomotion. 3. 3. The scratch test admits all particles over a certain size and rejects all smaller ones, while the handle test rejects all large, as well as some small, particles. Particles accepted at the fit test lie inside the size range of handle-accepted particles. 4. 4. The criteria for these tests include ones of size but not weight. 5. 5. Estimation of the size of particles is not visual but may be assessed by the displacement of the legs holding the particle. 6. 6. Amputation of up to three legs has little effect on the size of particle accepted. 7. 7. The acceptability of small particles at the scratch test depends on the size of the largest dimension of a particle, and acceptability at the handle and fit tests depends on the volume of a particle. 8. 8. There is no shape discrimination at the scratch or handle test, though there may be at the fit test.