Publications by authors named "Bercovitch F"
Article Synopsis
- This study focuses on analyzing the sex steroids testosterone and progesterone in wild giraffes, filling a gap in knowledge about their endocrine profiles in this species.* -
- Research conducted at Rooipoort Nature Reserve showed that pregnant giraffe females have higher progesterone levels, while male testosterone is linked to age, testicle size, and ossicone volume.* -
- The findings suggest that hormonal changes in both sexes influence reproductive strategies and maternal care, with male giraffe ossicones playing a role in competitive behavior during mating.*
Article Synopsis
- Improving the captive conditions for pygmy slow lorises is challenging due to limited knowledge about their wild behavior, suggesting a need for a new genus classification.
- A study at the Japan Monkey Center found that social housing significantly reduced stress levels in pygmy slow lorises, as indicated by lower fecal glucocorticoid levels and the disappearance of stereotypic behaviors in social settings.
- The findings highlight the social nature of pygmy slow lorises, indicating that group housing not only enhances their well-being but also aids in their conservation and potential reintegration into the wild.
Article Synopsis
- * An observation study of Japanese macaques revealed that males in vegetated enclosures engaged in more social play and had better coat conditions compared to those in non-vegetated enclosures, who displayed more stereotypic and agonistic behaviors.
- * While both groups had time budgets similar to wild counterparts, the vegetated enclosure males showed increased feeding activities and reduced resting time, indicating a significant benefit to wellbeing in naturalistic settings.
Article Synopsis
- Pygmy slow lorises are endangered and their secretive, nocturnal habits make them challenging to study in the wild, but new research reveals they may be more social than previously believed.
- A study at the Japan Monkey Centre observed the social dynamics of six adult female slow lorises moved from solitary cages to enriched group environments, focusing on their interactions and behaviors.
- Findings showed that these females formed strong social bonds, preferred being close to each other, nested together, and engaged in more grooming while spending less time moving around, indicating the importance of social companionship for their welfare.
Article Synopsis
- Fission-fusion social systems involve groups frequently changing in size and membership due to ecological and social factors, such as birth and death.
- In a study of giraffes in Katavi National Park, researchers found that female giraffes with offspring have stronger social ties than those without, and that calves and juveniles share similar patterns of social association.
- The study suggests that the presence of dependent young influences female social behavior, and nursery groups may help mothers by providing cooperative care and helping young giraffes develop important social skills for their future.
Article Synopsis
- Non-invasive stress measures are important for conservation and management of captive animals, and DHEAS is being explored as a stress marker in addition to traditional glucocorticoids (GC).
- The study analyzed fecal concentrations of DHEAS and GC in both captive and wild orangutans to evaluate their stress responses, particularly during stressful events like transportation.
- Results indicated a delayed increase in DHEAS levels after GC response, with significant differences in hormone levels based on age and reproductive state, suggesting the GC/DHEAS ratio can effectively indicate stress response variations in orangutans.
Article Synopsis
- The study focuses on the salivary alpha-amylase (sAA) enzyme, which aids in starch digestion and is linked to stress response via norepinephrine release in humans and non-human primates.
- Researchers aimed to create a non-invasive method to collect saliva from Japanese macaques and validate sAA as an acute stress biomarker in them.
- Results showed that after experiencing acute stress, sAA levels quickly increased and returned to baseline after approximately 10 minutes, providing insights into stress response dynamics in these primates.
Article Synopsis
- Maternal care for deceased infants in wild and captive mammals impacts social behavior and mother’s physiological status, but the specifics remain unclear.
- A study of a free-ranging female Japanese macaque showed that carrying her dead infant for 20 days led to increased fearful behaviors, like grimacing and avoiding others, and decreased grooming interactions.
- Despite these behavioral changes, the mother’s stress hormone levels returned to normal quickly, suggesting low energetic costs, and indicating that carrying deceased infants might help manage stress from loss.
Article Synopsis
- Various mammalian species, including olive baboons, African elephants, and Thornicroft's giraffes, exhibit behaviors where they care for or carry deceased young or companions, though the reasoning behind this is still unclear.
- The proposed hypothesis suggests that maternal behavior, driven by oxytocin—a key hormone for bonding and nurturing—is crucial for a female's reproductive success, leading to the development of social bonds in group-living animals.
- The text outlines potential methods for testing this hypothesis and discusses ways to possibly refute it, emphasizing the connection between physiology and social behavior in animals.
Article Synopsis
- - The survival of animals in extreme climates is influenced by their physiology, morphology, behavior, and habitat, with Japanese macaques notably adapting to cold environments through various thermoregulatory methods like using hot springs.
- - A study of 12 adult female Japanese macaques revealed that those with higher social rank access hot springs more readily, benefiting from lower glucocorticoid levels, which helps manage stress and body heat.
- - Despite the benefits of high social rank, dominant females experience increased aggression and higher glucocorticoid levels during winter, highlighting the complex trade-offs in social hierarchies among these primates.
Article Synopsis
- Population control through methods like castration is important for animal welfare and can be a viable alternative to lethal solutions, but must be carefully managed to avoid disrupting social structures.
- The study focused on behavioral and hormonal differences between castrated and intact male Japanese macaques, observing six intact males and 13 castrated males in different environments.
- Results indicated castrated males had a less aggressive social hierarchy, with lower testosterone levels, while hormonal levels varied with age, season, and social rank, illustrating complex interactions between physiology and behavior.
The link between laterality in humans and other primates is still hotly debated. Hylobatids have been rather neglected in this research area, yet they can provide important insights because: (1) they share with humans a complex vocal repertoire, which in humans is thought to be associated with brain hemispheric specialization and lateralized behaviors; (2) their adaptation to arboreality has produced unique postural constraints; (3) the little that is known about laterality in gibbons is contradictory (captive studies have provided conflicting results, while a field study on siamangs reported a population-level left-hand preference). To clarify this, we investigated hand preference in captive hylobatids [n = 42; 22 siamangs (Symphalangus syndactylus) and 20 gibbons (Hylobates sp.
View Article and Find Full Text PDFArticle Synopsis
- - Fennessy and colleagues' recent paper claims that there are four distinct species of giraffe, rather than the currently accepted one species with nine subspecies, and highlights a decline in giraffe populations in Africa.
- - Giraffes are currently listed as 'Vulnerable' on the IUCN Red List, but their taxonomy has been debated due to varying classifications and the methods used to evaluate them.
- - The differing interpretations of giraffe taxonomy arise from the use of different datasets, statistical techniques, and nomenclature criteria by researchers.
Article Synopsis
- Daylight saving time (DST) could potentially lower wildlife collisions by adjusting commuter traffic to align better with nocturnal animals' behavior.
- A study tracked wild koalas in southeast Queensland, where their population has significantly dropped, to see how their movements correlated with traffic patterns on dangerous roads.
- Results indicated that implementing DST could reduce koala collisions by 8% on weekdays and 11% on weekends, suggesting that wildlife safety should be considered in discussions about DST changes.
Article Synopsis
- Dehydroepiandrosterone-sulfate (DHEAS) is crucial for producing estrogens during pregnancy in primates and may indicate fetal health status.* -
- The study involved 16 pregnant female Japanese macaques and analyzed fecal samples for DHEAS, estrogen, and progesterone to assess pregnancy outcomes.* -
- Findings suggest that low fDHEAS levels may signal unsuccessful pregnancies, indicating its potential use for monitoring fetal health in both captive and wild primate populations.*
Despite being a charismatic and well-known species, the social system of the koala (Phascolarctos cinereus--the only extant member of the family Phascolarctidae) is poorly known and much of the koala's sociality and mating behaviors remain un-quantified. We evaluated these using proximity logging-GPS enabled tracking collars on wild koalas and discuss their implications for the mating system of this species. The frequency and duration of male-female encounters increased during the breeding season, with male-male encounters quite uncommon, suggesting little direct mating competition.
View Article and Find Full Text PDFArticle Synopsis
- Genetic studies enhance our understanding of behavior and health variations, providing models for human traits, and primate research is particularly valuable due to their close evolutionary links to humans.
- The free-ranging rhesus macaque population on Cayo Santiago, Puerto Rico, offers an exceptional opportunity for genetic research, with over 40 years of continuous study since 1956, including paternity testing and analysis of genetic markers.
- Recent research on the CS macaques has expanded to include functional genetics, behavioral studies, and potential applications for understanding human health issues, while future directions involve advanced techniques like SNP typing and whole genome sequencing.
Article Synopsis
- Non-invasive hormonal profiling using fecal glucocorticoids (fGC) and DHEAS in captive Japanese macaques offers insights into their stress levels, physical fitness, and adaptability to environmental changes.
- The study involved female monkeys aged 4 months to 31 years, revealing that those housed in single cages had higher fGC and DHEAS levels compared to their counterparts in social groups outdoors.
- Findings indicate that fGC levels peak during the mating season and decline in lactating females, with age negatively correlating with these hormone levels, highlighting the potential for hormonal measurement to assess stress and aid in conservation strategies.
Article Synopsis
- The study analyzed serum samples from 18 free-ranging and 22 zoo-based koalas at San Diego Zoo to investigate their health.
- Key nutrients like calcium, chloride, molybdenum, selenium, and vitamin E were found in higher concentrations in zoo-based koalas, while free-ranging koalas had more magnesium, manganese, phosphorus, and zinc.
- No gender differences were observed, and the findings will help establish baseline nutrient levels for koalas in health assessments.
Article Synopsis
- Dehydroepiandrosterone (DHEA) and its sulfate (DHEAS) are key steroid hormones, with DHEAS serving as a potential marker for aging in primates due to its decline over time.
- This study focused on Japanese macaques, examining fecal DHEAS levels across different ages and seasons to understand age-related hormonal changes.
- Results showed a negative correlation between DHEAS concentration and age, with neonatal macaques exhibiting the highest levels, potentially aiding in their neurobiological development.
Article Synopsis
- The study focuses on the size of zoo enclosures and the natural activity levels of elephants, highlighting the need for accurate walking distance data.
- Researchers used an accelerometer alongside a GPS unit to estimate and compare the walking distances of African elephants at the San Diego Zoo's Wild Animal Park.
- Findings indicated that while the accelerometer overestimated step counts and walking distances, its activity level measurements were significantly correlated with actual walking distances, leading to a regression equation that other institutions can use for similar assessments.
Article Synopsis
- Zoos face challenges in ensuring that animals raised in captivity have development patterns similar to those born in the wild, particularly with the long lifespans of species like African elephants.
- Research indicates that zoo-born elephant calves stand and walk independently at the same age as their wild counterparts, although they may take slightly longer to successfully nurse.
- Maternal experience affects the timing of nursing, but not the onset of standing or walking, suggesting that zoo and wild elephant calves generally develop at similar rates.
Article Synopsis
- The study observed four male koalas at the San Diego Zoo over eight weeks, revealing that while E. camuldulensis was the top choice, individual preferences varied among subjects.
- The results suggest that multiple intrinsic and extrinsic factors influence koala food choices, indicating they have evolved a flexible approach to foraging across different Eucalyptus species.
Article Synopsis
- Female primates, particularly primiparous rhesus macaques, face significant challenges during pregnancy and lactation, making it crucial to understand the factors influencing their postpartum recovery and infant development.
- This 2-year study at the Caribbean Primate Research Center investigated how maternal pre-conception condition affects these aspects in macaques, focusing on foraging time, alertness, and infants' nursing time.
- Findings revealed that maternal condition prior to conception significantly impacted postpartum recovery and infant development, with older primipares recovering better, while maternal feeding time and infant nursing duration did not play a key role.