Artifact Of Captivity Research Articles

Adult\u2013adult play in captive lowland gorillas (Gorilla gorilla gorilla)

Among African great apes, play is virtually absent between adult lowland gorillas (Gorilla gorilla gorilla). Here, we report an extremely rare case of adult–adult play observed in the lowland gorilla group housed at La Vallée de Singes (France). We recorded three playful interactions between the silverback and an adult lactating female. Given the diverse causal and functional nature of play, different factors may join in promoting this behaviour. In our group, contrary to what has been shown by previous studies in wild and captive gorillas, adult females spent more time in spatial proximity with the silverback than with other females. Hence, the probability of social interaction (including play) between silverback and adult females was enhanced. Moreover, the motivation of the lactating female to play might be an effect of oxytocin, a hormone that reaches high concentration levels during lactation and that promotes social affiliation. The fact that play invitations were always performed by the female might support this hypothesis. Certainly, we cannot exclude the possibility that the play event is a group idiosyncrasy or an artefact of captivity, even though the subjects never showed abnormal behaviour. Structurally, play sessions showed a suitable degree of pattern variability and switching frequency from one pattern to another. The proportion of offensive patterns was higher in the female during play and in the male during aggression, which conforms to the role reversal play phenomenon. In conclusion, this report confirms that the absence of evidence is not the evidence of absence. It is likely that under particular physiological or socio-ecological conditions, adult–adult play may be manifested as an “unconventional” part of gorilla social behaviour.

Curiosity boosts orang-utan problem-solving ability

Investigating the mechanisms underlying individual variation in cognitive performance is a crucial step towards understanding the structure and evolution of cognition. In this study, we investigated phenotypic plasticity of 61 Bornean, Pongo pygmaeus, and Sumatran, Pongo abelii, orang-utans to gain insight into how rearing history shapes problem-solving approaches. We first examined the determinants of an individual's response-and-exploration style, which we assessed using five independent novelty response and exploration tasks. Our findings revealed that both previous care by humans and social housing with conspecifics elicited a curious response-and-exploration style (characterized by a positive response to novelty and a high motivation to explore). Second, we investigated how the response-and-exploration style and previous experiences affected an individual's problem-solving performance in a variety of tasks aimed at assessing physical cognition, including reversal learning, inhibitory control, causal reasoning and tool use. We found curiosity to be the sole predictor of problem-solving performance. However, curiosity is strikingly rare in wild orang-utans, being mainly induced by contact with humans and living in a safe and stimulating physical and social environment. We therefore suggest that curiosity in orang-utans is an artefact of captivity, a potential only expressed under special conditions. The origin of curiosity in our own lineage may have been an important contributor to the rapid rise in the complexity of our ancestors' material culture.

Wheel running in the wild.

The importance of exercise for health and neurogenesis is becoming increasingly clear. Wheel running is often used in the laboratory for triggering enhanced activity levels, despite the common objection that this behaviour is an artefact of captivity and merely signifies neurosis or stereotypy. If wheel running is indeed caused by captive housing, wild mice are not expected to use a running wheel in nature. This however, to our knowledge, has never been tested. Here, we show that when running wheels are placed in nature, they are frequently used by wild mice, also when no extrinsic reward is provided. Bout lengths of running wheel behaviour in the wild match those for captive mice. This finding falsifies one criterion for stereotypic behaviour, and suggests that running wheel activity is an elective behaviour. In a time when lifestyle in general and lack of exercise in particular are a major cause of disease in the modern world, research into physical activity is of utmost importance. Our findings may help alleviate the main concern regarding the use of running wheels in research on exercise.

Differences in Ultrasonic Vocalizations between Wild and Laboratory California Mice (Peromyscus californicus)

BackgroundUltrasonic vocalizations (USVs) emitted by muroid rodents, including laboratory mice and rats, are used as phenotypic markers in behavioral assays and biomedical research. Interpretation of these USVs depends on understanding the significance of USV production by rodents in the wild. However, there has never been a study of muroid rodent ultrasound function in the wild and comparisons of USVs produced by wild and laboratory rodents are lacking to date. Here, we report the first comparison of wild and captive rodent USVs recorded from the same species, Peromyscus californicus.Methodology and Principal FindingsWe used standard ultrasound recording techniques to measure USVs from California mice in the laboratory (Peromyscus Genetic Stock Center, SC, USA) and the wild (Hastings Natural History Reserve, CA, USA). To determine which California mouse in the wild was vocalizing, we used a remote sensing method that used a 12-microphone acoustic localization array coupled with automated radio telemetry of all resident Peromyscus californicus in the area of the acoustic localization array. California mice in the laboratory and the wild produced the same types of USV motifs. However, wild California mice produced USVs that were 2–8 kHz higher in median frequency and significantly more variable in frequency than laboratory California mice.SignificanceThe similarity in overall form of USVs from wild and laboratory California mice demonstrates that production of USVs by captive Peromyscus is not an artifact of captivity. Our study validates the widespread use of USVs in laboratory rodents as behavioral indicators but highlights that particular characteristics of laboratory USVs may not reflect natural conditions.

Equine stereotypies: Current theories and future directions

Spontaneous stereotypic behaviour is conceptualised as topographically invariant, repetitive, rigid behaviour patterns, typically thought to be an artefact of captivity (Mason and Rushen 2006). In horses, stereotypic behaviours are commonly reported, probably owing to the high numbers of domesticated animals maintained under restrictive conditions (Parker et al., 2008a; Waters et al. 2002). Spontaneous stereotypies displayed by the horse include both oral (e.g., cribbing/windsucking) and locomotor (e.g., weaving and box-walking). There are a variety of extant theories as to what causes these behaviours, ranging from boredom to genetic predisposition and everywhere in-between. Affecting up to 35% of domestic horses in the UK, stereotypies represent a significant challenge for owners and a clear understanding of their aetiology is important in order to move to reduce the incidence. Recent advances in our understanding of the behavioural and neurobiological processes involved in the development and maintenance of drug-induced stereotypies in laboratory animals may provide us with a useful model for a better understanding of the spontaneous equivalent.

Multimodal signaling in wild Lemur catta: Economic design and territorial function of urine marking

Urine marking has been neglected in prosimian primates. Captive studies showed that the Malagasy prosimian Lemur catta scent marks with urine, as well as via specialized depositions. L. catta urine mark, a multimodal signal, differs from simple urination in terms of different design features, including tail configuration: the tail is held up during marking (UT-up) and down during urination (UT-down). We explore economy and function of UT-up in the female dominant L. catta. We collected 240 h of observations on one group at Berenty (south Madagascar) during the nonmating period via all occurrences sampling. We gathered behavioral bouts/contexts (marking, traveling, feeding, resting, and fights) and recorded 191 UT-ups and 79 UT-downs. Via Global Positioning System we established the location of the places frequented i) by extragroup individuals and ii) by group members, in this case recording also behavioral context and time spent in each place. We found that L. catta UT-up is not an artifact of captivity. Moreover, UT-up in the nonmating period plays a role in territorial defense, which is mostly performed by females in L. catta society. Female UT-ups were the most investigated and UT-ups were performed/investigated more by females. Finally, signal use is parsimonious, in that urine is economically placed where and when detection probability by competitors is higher. UT-ups were performed in places most frequented by extragroup individuals and in presence of extragroup competitors (nonrandom topography and timing). In conclusion, we suggest that UT-up is an economical signal with a primarily territorial function.

Dental Anomalies and Incidence of Palatal Erosion in Namibian Cheetahs (Acinonyx jubatus jubatus)

Two hundred and eight wild-caught cheetahs (Acinonyx jubatus jubatus) were live trapped on Namibian farmlands and examined for signs of dental anomalies. Three anomalies were recorded: erosion of the upper palate (possibly a predisposition to focal palatine erosion, where the first lower molar penetrates the palatine mucosa), crowding of lower incisors, and absence of one or both upper premolars. Just over 40% of cheetahs examined showed deep palatine erosion, and 15.3% of these had perforated upper palates. In addition, 31.7% of cheetahs examined had crowded lower incisors and 20.9% had one or both upper premolars missing. The incidence of focal palatine erosion is of particular interest as it has previously been recorded only in captive cheetahs, where it was attributed to a soft captive diet, and not previously recorded for wild individuals. To attempt further understanding of potential causes of such erosion, degree of erosion was examined in relation to sex, age, region, time in captivity, and occurrence of other dental anomalies. No relationship was found between severity of erosion and time spent in captivity, while juveniles showed more severe erosion than adult cheetahs. Cheetahs missing either one or both upper premolars showed a higher incidence of deep erosion, as was true for cheetahs that exhibited crowded lower incisors. The traditional explanation of focal palatine erosion being an artifact of captivity does not explain its occurrence in this sample population of cheetahs, the majority of which were raised entirely in the wild.

Multiple paternity in field- and captive-laid egg strands of Sepioteuthis australis (Cephalopoda:Loliginidae)

Previous observations on the mating behaviour of the southern calamary, Sepioteuthis australis Quoy & Gaimard 1833, revealed the potential for multiple paternities within egg strands, which contained up to eight eggs each. Six egg masses were laid in captivity from a possible 14 female and 20 male parents. By using five microsatellite loci, 112 eggs from 35 randomly selected egg strands were assigned sires using the potential fathers’ genotypes. Seven egg strands containing 22 eggs were also collected from the field to test that squid in captivity were apportioning eggs in natural ways, and that multiple paternity within egg strands was not an artefact of captivity. Ninety-seven per cent of strands laid in captivity showed multiple paternities. Similarly, multiple fathers were also evident in the field-laid egg strands. The maximum number of sires found within a single egg strand was four; however, three sires were more common. This is the first account of multiple paternities within egg strands laid by Sepioteuthis. It is likely that females are ‘spermatophore-limited’ when egg laying, and are promiscuous to ensure a ready supply of these sperm packets. Moreover, genetic diversity in a brood is increased by this mating strategy.

Homosexual behavior in wild Sumatran orangutans (Pongo pygmaeus abelii).

Wild male Sumatran orangutans at two study sites engaged in homosexual behavior. These observations demonstrate that homosexual behavior is not an artifact of captivity or contact with humans. In separate instances, homosexual behavior was associated with affiliative and agonistic behaviors. These observations add orangutans to the list of primates in which homosexual behavior forms part of the natural repertoire of sexual or sociosexual behavior.

Exercise training lowers the resting metabolic rate of Zebra Finches, Taeniopygia guttata

Summary Although changes in the mass and biochemistry of vertebrate locomotory muscle are established responses to exercise training, the effects of training on resting metabolic rate (RMR) are not clear. Here, a sustained flight training regime was shown to lower both the night‐time and day RMR of captive Zebra Finches (Taeniopygia guttata). Training also reduced fat reserves and overall body mass. Our results are largely consistent with the effects of an elevated energy expenditure on night‐time RMR detected in a study of workload on Zebra Finches but contrast with most studies of humans, where exercise training increases or has no effect upon RMR. A compensatory lowering of RMR in response to increased physical activity may be an artefact of captivity and could be dependent upon the activity levels of the captives concerned. It is suggested that when extrapolating from cage bird studies to wild situations, consideration should be given to the physical condition of the caged individuals being used. Variation in physical fitness may account for some of the unexplained variation in comparative studies of basal metabolism.

The Praying Mantids

The Praying Mantids

Insectivory in captive Livingstone's and Rodrigues fruit bats Pteropus livingstonii and P. rodricensis (Chiroptera: Pteropodidae): a behavioural adaptation for obtaining protein

Captive Pteropus livingstonii and P. rodricensis were observed actively to catch and eat insects. Both species adopt the same technique to trap flying insects, using their wings to envelop them. The spontaneity of the response indicates that it is not an artefact of captivity. The behaviour was observed in captive‐bred P. rodricensis which had no prior access to insects, suggesting that it is also innate. A higher rate of successful captures was recorded for an older, wild caught P. livingstonii female, indicating that the effectiveness of the technique used may improve with age. Significant differences in the amount of time spent catching insects by males and females were evident in this species. This study supports suggestions that insects are eaten by some megachiopterans in order to supplement their protein intake.

Breeding Biology of Brushtail Possums Trichosurus vulpecula (Marsupialia, Phalangeridae) in Captivity.

The brushtail possum is a common arboreal marsupial that is well adapted to the Australian urban environment and to rearing in captivity. Data obtained from 100 female possums housed in a semi-captive colony over a 7 year period demonstrate the reproductive capability of this marsupial. The main breeding season is from March to June with a declining number of births occurring from July to October. The possums gave birth to 259 single young and one set of twins. The range of the lactation period was from 177 to 200 days with the birth of the subsequent young occurring at 188.4 ± 4.1 days post partum (SD, n = 5). The growth rate of the young female possum varied greatly after day 100 post partum, the mean body weight of possums at day 172, being 753.0 ± 76.2g (SD, n = 5) with a range of 685 to 851 g. Female possums, with a mean body weight of 2171 ± 388g, gave birth to their first litter on day 345.9 ± 69.3 days postpartum (mean, SD, n = 7). Although two female possums trapped in the wild were held in captivity for 64 and 63.4 months and one possum bred in captivity had a life span of 51.5 months, the mean life span was 21.0 ± 12.5 months (SD, n =3D 8), with a range of 14.3 to 51.5 months. This life span is very variable and it is of interest to determine if this is an artefact of captivity or is also observed in the wild.

The agonistic and sexual functions of vocalizations of male brown-headed cowbirds, Molothrus ater

Functional analyses of three vocalizations of male brown-headed cowbirds, Molothrus ater, are presented and it is shown that two of these function as songs. Perched song (PS) is given by stationary birds and is used over short distances in male-male aggression and female courtship. The ‘flight whistle’ (FW) is a multisyllabic, usually pure tone, vocalization and the ‘single syllable flight call’ (SS) a monosyllabic pure tone. FWs and SSs are given occasionally by perched males and repetitively by flying males. Field playbacks of FWs showed that male cowbirds responded in the agonistic way most passerines respond to playback of conspecific song. Playbacks of the female's chatter call demonstrated that males of all three subspecies use FWs and SSs, but almost never PSs, to communicate with a female as they approach her. Thus FWs and SSs are used to communicate over long distances with both males and females. FWs are also used in one critical short-distance context as they are significantly more likely than PSs to be given just before copulations in nature, at least in our western study area. By contrast, studies of captive eastern cowbirds showed that PSs regularly precede copulations whereas FWs rarely do so. These different results for western and eastern birds may be an artefact of captivity and/or a result of geographical variation in behaviour.

The Family Group in Golden Hamsters: Its Formation and Break-Up

AbstractI. Behaviour of the golden hamster during normal parturition is described. 2. This is compared with behaviour of mothers who did not rear their litters because of faulty response to suckling attempts by the pups. Absence of milk at the nipples is suggested as a cause for this unwillingness to nurse. 3. Pups which are not born in the nest are often abandoned. 4. Pups born dead are often treated as food, but live pups are not eaten until after parturition is over. 5. Litters do not form into the characteristic compact unit until they have fed and been brooded. 6. Three stages in family break-up are recognised: (i) At about twentyfive days the mother begins to wean her litter, stops rebuilding the old nest, and may build a smaller one elsewhere. It is possible she would normally leave her litter at this point. (ii) During their fifth week the pups stop trying to suckle and showing contact behaviour ; they begin to sleep in small groups, and seem to try to escape from the mother's cage. At this time the mother attacks them occasionally. (iii) With sexual maturity of the females (six weeks) play-fighting stops, and marking was not seen. If a female becomes pregnant she becomes dominant in a few days, but does not dare fight the mother. 7. It is likely that the third stage is an artefact of captivity and that the litter would be left by the mother in stage (i) and would largely disperse during stage (ii) in natural conditions. 8. The interpretations of observations described are necessarily tentative, and need experimental tests before they can be accepted.