Toshikazu Hasegawa
Dados Biográficos
| ID | 3872863 |
|---|---|
| NOME | Toshikazu Hasegawa |
| PRENOMES | Toshikazu |
| SOBRENOME | Hasegawa |
| ASSINATURA | HASEGAWA T |
| AFILIAÇÕES | The University of Tokyo |
| VERIFICADO | Não |
| TOTAL DE OBRAS | 19 |
| TOTAL DE CITAÇÕES | 55 |
| TOTAL COMO AUTOR | 19 |
| TOTAL COMO EDITOR | 0 |
| PRIMEIRO ANO DE PUBLICAÇÃO | 1981 |
| ANO MAIS RECENTE DE PUBLICAÇÃO | 2018 |
| ÍNDICE H | 3 |
The presence of females induces elevated cortisol levels in an alpha male
OBJECTIVES: In group-living primates, it has been reported that the alpha male exhibits high concentrations of cortisol and testosterone in the context of mating competition. We investigated how the presence of females affected salivary cortisol and testosterone levels in males from a small captive group of chimpanzees (Pan troglodytes). Specifically, we assessed whether the presence of females resulted in a rapid increase in salivary cortisol an…
The effect of spatial frequency and face inversion on facial expression processing in children with autism spectrum disorder
To investigate whether facial expression processing in children with autism spectrum disorder ( ASD ) is based on local information of the stimuli, we prepared low spatial frequency ( LSF ) images with blurred facial features and high spatial frequency ( HSF ) images with rich facial features from broad (normal) spatial frequency ( BSF ) images. Eighteen children with ASD (mean age 11.9 years) and 19 typically developing ( TD ) children (mean age…
Validation of salivary cortisol and testosterone assays in chimpanzees by liquid chromatography‐tandem mass spectrometry
Owing to its high temporal sensitivity, saliva has distinct advantages for measuring steroids, compared with other noninvasive samples such as urine and feces. Here, we report the validity of assaying salivary cortisol (C) and testosterone (T) using liquid chromatography‐tandem mass spectrometry (LC‐MS/MS) in captive male chimpanzees, Pan troglodytes . For both the C and T concentrations, we found positive relationships between saliva and plasma.…
Elephant psychology
Although elephants are well‐known and one of the most popular species among people, their behavior and cognitive abilities have not been studied very extensively. But recently, more and more researchers are becoming interested in studying their cognition, particularly their general intelligence, including causal reasoning and mirror self recognition, memory, and numerical cognition. Although genetically elephants are more closely related to the s…
Pattern, Distribution, and Function of Greeting Behavior Among Black-and-White Colobus
Demonstration of a genotype–phenotype correlation in the polymorphic color vision of a non‐callitrichine New World monkey, capuchin ( Cebus apella )
Color‐vision polymorphism in New World monkeys occurs because of an allelic polymorphism of the single‐copy red‐green middle‐to‐long‐wavelength‐sensitive (M/LWS) opsin gene on the X chromosome. Because color‐vision types can readily be estimated from allelic types of the M/LWS opsin gene, this polymorphic system offers researchers an excellent opportunity to study the association between vision and behavior. As a prerequisite for such studies, ge…
Advantage of dichromats over trichromats in discrimination of color‐camouflaged stimuli in nonhuman primates
Due to a middle‐ to long‐wavelength‐sensitive (M/LWS) cone opsin polymorphism, there is considerable phenotypic variation in the color vision of New World monkeys. Many females have trichromatic vision, whereas some females and all males have dichromatic vision. The selective pressures that maintain this polymorphism are unclear. In the present study we compared the performance of dichromats and trichromats in a discrimination task. We examined t…
Dominance Turnover Between an Alpha and a Beta Male and Dynamics of Social Relationships in Japanese Macaques
Reconciliation pattern after aggression among Japanese preschool children
Using an ethological observation method (the PC-MC comparison method), this study investigated patterns of reconciliation after aggression among Japanese preschool children, focusing on factors that influenced its occurrence or acceptance, as well as on strategies and function. There were several factors among four-year-olds that facilitated reconciliatory attempts and acceptance, such as proximity after the aggression; among three-year-olds ther…
Behavioral evidence of color vision deficiency in a protanomalia chimpanzee (Pan troglodytes)
Demography, female life history, and reproductive profiles among the chimpanzees of Mahale
Demography provides critical data to increase our understanding of the evolution, ecology, and conservation of primate populations. The chimpanzees of the Mahale Mountains National Park, Tanzania, have been studied for more than 34 yr on the basis of individual identification and standardized attendance records. From this long‐term study, we derived the following demographic data: The major cause of death was disease (48%), followed by senescence…
Jealousy and the nature of beliefs about infidelity
The different adaptive problems faced by men and women over evolutionary history led evolutionary psychologists to hypothesize and discover sex differences in jealousy as a function of infidelity type. An alternative hypothesis proposes that beliefs about the conditional probabilities of sexual and emotional infidelity account for these sex differences. Four studies tested these hypotheses. Study 1 tested the hypotheses in an American sample (N =…
Dialects in wild chimpanzees
Chimpanzees emit a loud, species‐typical long distance call known as the pant hoot. Geographic variation between the pant hoots of chimpanzees living in two neighboring populations, the Mahale Mountains and Gombe Stream National Parks, Tanzania, was examined. Analysis of six acoustic features revealed subtle differences in the way chimpanzees from the two populations called. Individuals from the Mahale study site uttered one section of their pant…
A case of offspring desertion by a female chimpanzee and the behavioral changes of the abandoned offspring
Group Extinction and Female Transfer in Wild Chimpanzees in the Mahale National Park, Tanzania
and Summary A unit‐group (K‐group) of chimpanzees has shown a drastic demographic change in the course of 17 years (1966–1983) of field study. K‐group had 6 adult males in 1966. Initially, the group lost adult males one by one between 1969–1975. The number of adult males in the unit‐group was the main factor influencing the immigration of strange, cycling females and the emigration of cycling females, although nulliparous females born into K‐grou…
Demographic study of a large-sized unit-group of chimpanzees in the mahale mountains, Tanzania
Chimpanzee predation in the Mahale mountains from August 1979 to May 1982
New Evidence on Scavenging Behavior in Wild Chimpanzees
A newly-discovered population ofColobus angolensis in East Africa
Chimpanzee predation in the Mahale mountains from August 1979 to May 1982
New Evidence on Scavenging Behavior in Wild Chimpanzees
Pattern, Distribution, and Function of Greeting Behavior Among Black-and-White Colobus
Reconciliation pattern after aggression among Japanese preschool children
Using an ethological observation method (the PC-MC comparison method), this study investigated patterns of reconciliation after aggression among Japanese preschool children, focusing on factors that influenced its occurrence or acceptance, as well as on strategies and function. There were several factors among four-year-olds that facilitated reconciliatory attempts and acceptance, such as proximity after the aggression; among three-year-olds ther…
A newly-discovered population ofColobus angolensis in East Africa
New Evidence on Scavenging Behavior in Wild Chimpanzees
Demographic study of a large-sized unit-group of chimpanzees in the mahale mountains, Tanzania
Chimpanzee predation in the Mahale mountains from August 1979 to May 1982
Group Extinction and Female Transfer in Wild Chimpanzees in the Mahale National Park, Tanzania
and Summary A unit‐group (K‐group) of chimpanzees has shown a drastic demographic change in the course of 17 years (1966–1983) of field study. K‐group had 6 adult males in 1966. Initially, the group lost adult males one by one between 1969–1975. The number of adult males in the unit‐group was the main factor influencing the immigration of strange, cycling females and the emigration of cycling females, although nulliparous females born into K‐grou…
A case of offspring desertion by a female chimpanzee and the behavioral changes of the abandoned offspring
Dialects in wild chimpanzees
Chimpanzees emit a loud, species‐typical long distance call known as the pant hoot. Geographic variation between the pant hoots of chimpanzees living in two neighboring populations, the Mahale Mountains and Gombe Stream National Parks, Tanzania, was examined. Analysis of six acoustic features revealed subtle differences in the way chimpanzees from the two populations called. Individuals from the Mahale study site uttered one section of their pant…
Jealousy and the nature of beliefs about infidelity
The different adaptive problems faced by men and women over evolutionary history led evolutionary psychologists to hypothesize and discover sex differences in jealousy as a function of infidelity type. An alternative hypothesis proposes that beliefs about the conditional probabilities of sexual and emotional infidelity account for these sex differences. Four studies tested these hypotheses. Study 1 tested the hypotheses in an American sample (N =…
Behavioral evidence of color vision deficiency in a protanomalia chimpanzee (Pan troglodytes)
Demography, female life history, and reproductive profiles among the chimpanzees of Mahale
Demography provides critical data to increase our understanding of the evolution, ecology, and conservation of primate populations. The chimpanzees of the Mahale Mountains National Park, Tanzania, have been studied for more than 34 yr on the basis of individual identification and standardized attendance records. From this long‐term study, we derived the following demographic data: The major cause of death was disease (48%), followed by senescence…
Demonstration of a genotype–phenotype correlation in the polymorphic color vision of a non‐callitrichine New World monkey, capuchin ( Cebus apella )
Color‐vision polymorphism in New World monkeys occurs because of an allelic polymorphism of the single‐copy red‐green middle‐to‐long‐wavelength‐sensitive (M/LWS) opsin gene on the X chromosome. Because color‐vision types can readily be estimated from allelic types of the M/LWS opsin gene, this polymorphic system offers researchers an excellent opportunity to study the association between vision and behavior. As a prerequisite for such studies, ge…
Advantage of dichromats over trichromats in discrimination of color‐camouflaged stimuli in nonhuman primates
Due to a middle‐ to long‐wavelength‐sensitive (M/LWS) cone opsin polymorphism, there is considerable phenotypic variation in the color vision of New World monkeys. Many females have trichromatic vision, whereas some females and all males have dichromatic vision. The selective pressures that maintain this polymorphism are unclear. In the present study we compared the performance of dichromats and trichromats in a discrimination task. We examined t…
Dominance Turnover Between an Alpha and a Beta Male and Dynamics of Social Relationships in Japanese Macaques
Reconciliation pattern after aggression among Japanese preschool children
Using an ethological observation method (the PC-MC comparison method), this study investigated patterns of reconciliation after aggression among Japanese preschool children, focusing on factors that influenced its occurrence or acceptance, as well as on strategies and function. There were several factors among four-year-olds that facilitated reconciliatory attempts and acceptance, such as proximity after the aggression; among three-year-olds ther…
Pattern, Distribution, and Function of Greeting Behavior Among Black-and-White Colobus
Validation of salivary cortisol and testosterone assays in chimpanzees by liquid chromatography‐tandem mass spectrometry
Owing to its high temporal sensitivity, saliva has distinct advantages for measuring steroids, compared with other noninvasive samples such as urine and feces. Here, we report the validity of assaying salivary cortisol (C) and testosterone (T) using liquid chromatography‐tandem mass spectrometry (LC‐MS/MS) in captive male chimpanzees, Pan troglodytes . For both the C and T concentrations, we found positive relationships between saliva and plasma.…
Elephant psychology
Although elephants are well‐known and one of the most popular species among people, their behavior and cognitive abilities have not been studied very extensively. But recently, more and more researchers are becoming interested in studying their cognition, particularly their general intelligence, including causal reasoning and mirror self recognition, memory, and numerical cognition. Although genetically elephants are more closely related to the s…
The effect of spatial frequency and face inversion on facial expression processing in children with autism spectrum disorder
To investigate whether facial expression processing in children with autism spectrum disorder ( ASD ) is based on local information of the stimuli, we prepared low spatial frequency ( LSF ) images with blurred facial features and high spatial frequency ( HSF ) images with rich facial features from broad (normal) spatial frequency ( BSF ) images. Eighteen children with ASD (mean age 11.9 years) and 19 typically developing ( TD ) children (mean age…
The presence of females induces elevated cortisol levels in an alpha male
OBJECTIVES: In group-living primates, it has been reported that the alpha male exhibits high concentrations of cortisol and testosterone in the context of mating competition. We investigated how the presence of females affected salivary cortisol and testosterone levels in males from a small captive group of chimpanzees (Pan troglodytes). Specifically, we assessed whether the presence of females resulted in a rapid increase in salivary cortisol an…
Biology (17 obras) · Primate Behavior and Ecology (14 obras) · Psychology (11 obras) · Zoology (9 obras) · Animal Behavior and Reproduction (8 obras) · Demography (8 obras) · Animal ecology (7 obras) · Geography (7 obras) · Tanzania (7 obras) · Developmental psychology (6 obras)