Milk secretion in pregnancy among free-ranging Japanese macaques

Milking under anesthesia in pregnant free-ranging Japanese macaques (Macaca fuscata) directly revealed lactation in gestation at Jigokudani Monkey Park, the Shiga Heights, Nagano Prefecture, Japan, from 12 to 14 February 1992. Multiparae secreted milk at 76–97 days of estimated fertilization age when the birth intervals to the next offspring were 2 years. The observation of sucking behavior from February 1991 to March 1992 indicated that concurrent suckling by these multiparae terminated approximately 70 days before the next parturition after the growth of fetuses had accelerated and the embryos survived the crisis of abortion. Thus, Japanese macaque mothers appear to hedge maternal investment with concurrent lactation against possible miscarriage. Two nulliparous pregnant females secreted milk 3 months before the first parturition although they had no suckers. The first preparation of lactation appears to require the duration of longer than 3 months in nulliparae although worked mammary glands appear to be able to resume within 1 month in multiparae. © 1993 Wiley-Liss, Inc.     

Grouping-patterns and inter-group relationships of Japanese wild boars (Sus scrofa leucomystax) in the Rokko mountain area

Grouping-patterns and inter-group relationships of Japanese wild boars (Sus scrofa leucomystax) were studied at a provisioning site in the Rokko mountain area, Hyogo Prefecture, Japan, from 1982 to 1983. The observations were divided into four study periods. Almost all wild boars were individually identified and their kin-relationships were followed from the beginning of the study. To examine grouping-patterns of Japanese wild boars, the degree of association between any two individuals, based on coexisting time at the provisioning site, was analyzed for each study period. Mother and her litter group (MLG), female littermate group (FLG) and solitary individual were recognized grouping-patterns. Groups did not associate with each other. Male offspring separated from their mother before 1 year of age and become solitary. Separation of female offspring occurred before the subsequent parturition of their mother. The proximate cause of separation was increased aggression by the mother. After separation, female offspring formed a FLG. However, the FLG seemed to be generally a temporary one, maintaining its stability only until parturition of it's members. Thereafter adult females had no close association with any other individuals, except for their own infants. Male offspring disappeared from their natal area, while female offspring could remain there.     

Morphological changes of female reproductive organs of Japanese monkeys with reproductive conditions

Macroscopic and histological changes were examined on the female reproductive organs of Japanese monkeys (Macaca fuscata) with varying reproductive status in enclosed and provisioned troops. The weight and size of reproductive organs are described. The size of uterus declined in 2–3 months after parturition. The number of parturition was roughly estimated by degrees of sclerosis in myometrial vessels. The nipple length of parous animals was longer than that of nulliparous ones. The bilateral difference in the length (more than 3 mm) between nipples indicated the experience of nursing. Interpreting ovaries on the basis of macroscopic examination alone was less precise. The present results suggested that the female sexual maturity and the experience of nursing can be estimated by the measurement of reproductive organs in the Japanese monkey.     

神农架川金丝猴初产雌性妊娠期异亲哺乳

<正>灵长类动物生长发育过程中,雌性往往承担着主要的育幼责任,因此,母亲是帮助灵长类婴儿尽早适应环境并独立生活的重要角色(F?rster and Cords, 2002; Xi et al., 2008; Briga et al., 2012)。对大多数群居型灵长类动物而言,母亲以外的成员也常常参与照料婴猴,该现象普遍存在于旧大陆猴中,     

Control of postpartum mating behavior in free-ranging rhesus monkeys

This paper explores the effect that a dependent rhesus macaque infant (Macaca mulatta) has on the timing of its mother's resumption of mating. Toward this end, behavioral data from the rhesus populations at Tughlaqabad, India, and Cayo Santiago, Puerto Rico, are compared. Specifically, the intervals between parturition and subsequent resumption of mating for individual parous females are examined in order to shed light on the relative importance of environmental and internal factors (such as lactational infertility) in the control of rhesus mating behvior. At both study sites it was found that the later a given female gave birth during a birth season the shorter was her parturition-mating interval and the younger was her infant when she resumed mating activity. It is suggested that this finding is the result of an interaction of environmental and internal factors; both act in concert to determine how soon after parturition a particular rhesus female will resume mating activity.     

Observation of a wild Japanese macaque mother pacifying her distressed infant with an acorn

This is the first report on an observation of food transfer by a mother to her offspring in wild Japanese macaques (Macaca fuscata yakui). On November 6, 1996, an adult female wild Japanese macaque stopped grooming her 1.5–1.6 yr old daughter in order to be groomed by a young male. Her daughter protested loudly for about 1 min. In response to her daughter's protest, the mother picked up a mature nut ofQuercus phillyraeoides that was lying near her right hand, and placed it in the daughter's mouth. The daughter's cries were immediately muffled and she silently ate the acorn's contents, and spat out the pericarp. We inferred that the daughter wanted to be groomed by her mother, not to receive food. This reported example of treatment resembling tool using behavior in response to an emotional outcry was precipitated by mother-offspring conflict in the natural habitat.     

Evidence that Mating Plug is Related to Null Female Mating Activity in the Scorpion Vaejovis punctatus

We document a case in which the mating plug of the scorpion Vaejovis punctatus seems correlated with a reduction in female sexual receptivity. We used two morphological and behavioral analyses. The mating plug was dissected and described from both males and females: it bears a set of spines and two enlarged terminations which possibly allow anchoring to the female inside and impede removal. Behavioral observations support this view: after sperm transfer ended, the female tried to remove the plug by rubbing the ventral side of her body using her second and third pair of legs. This pattern was also performed after mate separation. All females seemed unable to displace the plug and rejected male mating attempts. The mating plug suffered a progressive degradation into the female. This degradation was completed 2 or 3 mo prior to parturition, so that the plug did not seem a barrier for the emergence of embryos. Furthermore, females bearing mating plugs in different degradation stages did not accept another mating during the reproductive season, and sexual acceptance was reinitiated only after parturition. The mating plug therefore seems to correlate with a lost in mating activity. The comparison of this structure with that of other scorpion species allows us to hypothesize a sexual coevolutionary scenario in which the effectiveness of the plug to inhibit female remating may lie at the center of such interaction.     

Observation of a birth among wild toque macaques (Macaca sinica)

Most toque macaques give birth to their infants during the night when resting arboreally. Here we report on a birth that occurred in daytime (at 0916 hr) and on the ground. The mother was 7.6 years old; the birth was her second. Prepartum behaviors included lordosis, arching of the back, stretching, squatting, rolling on the ground, and anogenital self-examination. During the birth the female was isolated about 100 m from the rest of her group. The mother stood bipedally during parturition and assisted delivery with her hands. The infant was born within 2 min after first appearing at the vulva. It immediately clung to the mother’s leg and vocalized. The mother licked the infant and oriented it toward her ventrum. She resumed foraging behavior within 20 min after parturition. The infant nursed for the first time 2.25 hr after being born. The mother ate part of the placenta, but the alpha female of the group usurped and also ate a portion of it. Curious group members sniffed and looked at the infant but did not touch it.     

The effect of solicitations on grooming exchanges among female Japanese macaques at Katsuyama

In group-living primates, individuals often exchange grooming with not only kin but also non-kin. We investigated the effect of soliciting behaviors on grooming exchanges in a free-ranging Japanese macaque (Macaca fuscata) group at Katsuyama. In this study, we used a focal animal sampling method, targeting 14 females. Data were collected for 15.75 ± 2.67 (mean ± SD) hours per focal female. We classified female–female pairs into three pair types: kin pairs, affiliated non-kin pairs, and unaffiliated non-kin pairs. Females received grooming more frequently when they solicited after grooming their partners than when they did not solicit in all pair types. In addition, females received grooming less frequently when they did not groom their unaffiliated non-kin partners before soliciting; prior grooming was not needed to receive grooming from kin or affiliated non-kin partners. The degree of grooming reciprocity did not differ according to the frequency with which females in kin or affiliated non-kin pairs solicited after grooming. On the other hand, grooming reciprocity between unaffiliated non-kin females was more balanced when they solicited frequently after grooming, as compared with when they did not. In conclusion, our study suggests that soliciting behaviors promote grooming exchanges in female Japanese macaques.     

Availability and adaptive value of reproductive and postreproductive Japanese macaque mothers and grandmothers

Prior tests of the grandmother hypothesis have suggested that postreproductive female Japanese macaques,Macaca fuscata , do not significantly improve the survivorship of their descendents. However, not all postreproductive females are grandmothers, and not all grandmothers are postreproductive. In this study we looked at the daughters and grandchildren of 70 female Japanese macaques to assess the availability and adaptive value of reproductive and postreproductive mothers and grandmothers. We found that postreproductive Japanese macaque grandmothers are very rare. Only 2.8% of the sample of daughters had a postreproductive grandmother available when they began to reproduce, and only 4.2% of the reproductive life span of the daughter (less than 6 months for the average female) was spent with a postreproductive grandmother available to help the daughter. Grandchildren who survived to age 5 had a postreproductive grandmother available to them for only 4% of the first 5 years of life (i.e. a couple of months on average). The presence of a living mother, irrespective of her reproductive status, was associated with improved reproduction in her adult daughters, and the presence of a postreproductive grandmother was associated with significantly improved survivorship of grandchildren to age 1. While improved maternal investment does not appear to be the primary explanation for reproductive termination in Japanese monkeys, the few postreproductive females that have unweaned grandchildren available appear to have a positive influence on their survival. Copyright 2002 The Association for the Study of Animal Behaviour. Published by Elsevier Science Ltd. All rights reserved.     

Peripartum cortisol levels and mother-infant interactions in Japanese macaques

As evidence accumulates regarding the influence of hormones and stress-related conditions on maternal behavior, it becomes critical to better understand the relationship between physiological stress and the ability to cope with infants. Eight Japanese macaque females were observed 3 hr per week during the first 12 weeks after parturition; fecal samples were collected twice a week from each mother, starting 4 weeks before parturition and ending 4 weeks after parturition. Time spent in contact, maternal responsiveness, latency of response, and maternal rejection were measured and correlated with peripartum excreted cortisol and estradiol metabolite levels. Two indices of peripartum hormonal status were also tested against behavior: the postpartum stress index, and the postpartum cortisol/prepartum estradiol ratio (F/E). Postpartum cortisol levels showed a positive correlation with maternal rejection. The cortisol/estradiol ratio was positively correlated with rejection and latency of response, and negatively correlated with maternal responsiveness. Prepartum cortisol levels and the postpartum stress index did not correlate with any aspect of maternal behavior. Our findings suggest that hypothalamic-pituitary-adrenal (HPA) axis activity per se is not enough to predict the quality of interaction between mother and infant. Only when cortisol is high relative to estradiol could it be symptomatic of a possible negative feedback response involving stress, adrenal activity, and the ability of mothers to cope with the additional problems imposed by newborns.     

Initiation and solicitation in male-female grooming in a wild Japanese macaque troop on yakushima island

Grooming initiation among adult males and females of a Japanese macaque troop was analyzed during the non-mating season. Some gestures (“solicitation”) elicited grooming from partners at a high rate. Grooming initiation patterns were divided into two main types: (1) a male often solicited a female to groom him immediately after approaching her and was groomed by her; and (2) a female approached an alpha male selectively, and immediately groomed him. After a female groomed a male, she rarely solicited him to groom her and instead often moved away from him. These results indicated that males were motivated to be groomed, while females were more highly motivated to groom. Sex differences in grooming motivation can be explained by sex differences in the benefit to be groomed.     

Effects of parity and age on female attraction to faces of infants and neonates in rhesus macaques

This study investigated the effects of parity and age on female rhesus macaque attention toward infants, and assessed whether the faces of neonates are more attractive than those of older infants. Six nulliparous and six multiparous females were shown digitized images of neonates’ and 5- to 6-month-old infants’ faces. Attention and preferences for images were measured by gaze duration and other picture-directed behaviors, including lip smacking, approaches, and presentations. As predicted, nulliparous females displayed significantly longer gaze durations for images than did multiparous females. There were no significant differences in gaze duration for faces of neonates and those of infants, but images of infants were approached more frequently than images of neonates. This difference is tentatively explained on the basis of differences in female familiarity with neonates’ and infants’ faces and differences in opportunities for allomothering with neonates and infants.     

Adoption in free-ranging red howler monkeys,Alouatta seniculus of Venezuela

This report describes three cases of infant adoption in red howler monkeys (Alouatta seniculus) of Venezuela. In one case, a lactating female adopted her infant granddaughter after the infant's mother disappeared and the infant survived for the next 25 months. In the second case, an adult female adopted her infant granddaughter for nine days while the infant's mother was still a group member. In the third case, a nulliparous female temporarily adopted an infant from a neighboring group. The details and the possible reasons for these adoption are described.     

TIMING OF PARTURITION AS A MATERNAL CARE TACTIC IN AN ALPINE LIZARD SPECIES

Lack of ability to buffer postparturient offspring mortality risks may put a female under strong selection to time the birth of her young with benign environmental conditions. We provide support for timing of parturition as an adaptation in Tasmanian snow skinks (Niveoscincus) by demonstration of (1) ongoing selection against poorly timed parturitions, (2) retention of full-term young through episodes of unfavorable conditions, and (3) phylogenetic shifts from autumn to spring parturition in taxa where costs of autumn parturition are expected to be relatively higher.     

Grooming and aggression in captive Japanese macaques

This study investigated the relations between allogrooming and aggression in a captive group of Japanese macaques (Macaca fuscata). Our aim was to test whether evidence of an interchange between allogrooming and a reduction in aggression could be identified at a group level. Female Japanese macaques did not direct less aggression to those group mates that groomed them most. Although generally they did not direct more grooming to those group mates that attacked them most, they did show increased grooming towards those nonkin group mates that showed the most aggression. These results are interpreted in light of the conflicting processes that are likely to underlie macaque social choices.     

Positional behavior of free-ranging Japanese macaques (<Emphasis Type="Italic">Macaca fuscata</Emphasis>)

Positional behavior was quantitatively studied in identified free-ranging Japanese macaques (Macaca fuscata). Five male and 11 female adults were observed in a forested mountain habitat. Data were analyzed for proportion of bout distance, number and time of each locomotion and postural type. Japanese macaques are semiterrestrial, and mainly walk and run quadrupedally. This supports the notion that Macaca are generally quadrupeds. Sex differences in positional behavior were found in the preference of substrate and types of positional behavior. Males and females tend to be terrestrial and arboreal, respectively. Males leap more frequently and longer in distance than do females when they are feeding in trees. These sex differences are considered to be related to differences in morphology, food choice, social activity, and the nursing of infants. Frequencies of leaping and the distance covered by leaping in Japanese macaques are more than those of long-tailed macaques which are arboreal quadrupeds. However, Japanese macaques leap shorter distances at a time than do long-tailed macaques, which indicates that body size may be related to leaping distance more than the frequency of leaping and the distance covered by leaping. Japanese macaques are not as specialized for terrestrial locomotion as pig-tailed macaques. They use both terrestrial and arboreal supports, and are considered to be semi-terrestrial quadrupeds, somewhere between the arboreal long-tailed macaque and the terrestrial pig-tailed macaque. Electronic Publication     

Sexual behavior of wild Barbary macaque males (Macaca sylvanus)

Recent assertions that the Barbary macaque (Macaca sylvanus) is a multiple-or serial-mounting species are incorrect. Data are presented from over 300 copulations observed among wild Moroccan Barbary macaques which establish empirically that males of this macaque species are single mounters. The average length of an ejaculatory copulation was 8.7 sec, with a range of 6 to 14 sec. Ejaculation occurred an average of 6.3 sec after mounting, with an average of nine pelvic thrusts per ejaculation. Males appeared capable of ejaculating twice within 16 min, and three consecutive times within 37 min. Characteristically, only one mount and ejaculation occurred during a sexual association between an estrous female and each of her consorting males. Schemes of macaque evolution which incorrectly classify Barbary macaques as a multiple-mounting species should be viewed cautiously.     

Female rank and reproductive success among arashiyama B Japanese macaques (Macaca fuscata)

Five hypotheses that related female rank and reproductive success were tested in an intact troop of free-ranging, provisioned, Japanese macaques. The hypotheses stated that high-ranking females (1) begin parturition earlier in life than low-ranking females; (2) produce more offspring than low-ranking females; (3) give birth during some optimal time during the birth season to a greater extent than low-ranking females; (4) experience less infant mortality than low-ranking females;and (5) more frequently produce male offspring, while low-ranking females more frequently produce female offspring. A statistical analysis of the data which included three birth seasons and 55 adult females and 34 pubescent females, all of known age, rank, and matrifocal membership in the Arashiyama B troop, revealed few significant results. An association was found between the rank of the matrifocal unit and the age of first birth. However, the relationship was the reverse of hypothesis 1, i.e., females of the lower-ranking matrifocal units began parturition earlier than females of higher-ranking matrifocal units. Therefore, in this troop of Japanese monkeys— where alternative feeding strategies existed— there was little association between female rank and reproductive success.     

The Influence of Age,Sex, and Rank on Yawning Behavior in Two Species of Macaques (Macaca fascicularis and M. fuscata)

Yawning behavior was studied in two species of macaques: the long-tailed macaque (Macaca fascicularis) and the Japanese macaque (M. fuscata). Japanese macaques yawned much more than long-tailed macaques. Age, sex, and dominance rank exerted different effects on yawning in the two species. In the long-tailed macaques, sex differences in frequency of yawning emerged only after sexual maturity; yawning rates increased significantly in both males and females as they reached sexual maturity; and, among males, dominance rank was positively correlated with frequency of yawning. Differently, in the Japanese macaques, males, both mature and immature, yawned more than same-aged females; sexual maturity was associated with an increase in yawning in males only; and male rank did not correlate with the frequency of yawning. Regardless of interspecific differences, the overall results supported only in part the finding that, in Old World monkeys, yawning is largely influenced by plasma concentrations of androgens. There was evidence that social factors were also important in influencing the age-sex class distribution of yawning.