Publications by authors named "Andrew J J Macintosh"
Article Synopsis
- Disease outbreaks pose significant risks to great apes and wildlife, and understanding social networks is crucial for predicting how diseases spread among these populations.
- The study focused on wild chimpanzees and explored how individual traits like sex and age influence their social connections and role in disease transmission.
- Results revealed that older males are more socially central, which affects their likelihood of infection, especially for highly transmissible pathogens with longer infectious periods, emphasizing the need to consider social dynamics in disease outbreak research.
Article Synopsis
- Maternal behavior in primates shows significant variation and influences the behaviors of their immature offspring, but the extent of this impact is still not fully understood.
- In a study of Japanese macaques, researchers found that juveniles with mothers who frequently rejected them were more likely to engage with peers, even when mothers were absent, indicating a lasting effect of maternal rejection.
- Conversely, juveniles with more protective mothers tended to play less and interact less with others, but this influence seemed to diminish when the mother was not nearby, suggesting different dynamics between maternal rejection and protectiveness.
Article Synopsis
- - The study examines how colobus monkeys (Colobus vellerosus) adapt their behaviors regarding intergroup aggression as their population grows, focusing on who contributes to public goods like food defense and home range security.
- - Both male and female monkeys engage in group encounters to defend food resources; however, females participate more as the competition increases, highlighting their role in home range defense.
- - Despite females taking more initiative in defending social and resource stability, males still play a significant role in intergroup interactions, suggesting they might not be able to contribute more due to limited resources or time.
Article Synopsis
- Non-human primates (NHPs) are facing population declines due to various threats, including diseases caused by parasites, bacteria, and viruses.
- Strongylid nematodes are common parasitic infections in NHPs, but their diversity is hard to study due to mixed infections not being distinguishable by traditional methods.
- This study used advanced metagenomics techniques to analyze strongylid infections in NHPs from Malaysia and Japan, finding that the communities in Asian NHPs may be less diverse than those in African NHPs, providing key data for monitoring NHP health.
Article Synopsis
- The study explores how individual interactions shape complex societies, focusing on social networks formed by maximizing benefits and minimizing costs in relationships.
- An agent-based model was created to show how individuals choose interactions based on social attraction to beneficial partners and avoidance of costly ones, leading to different types of network structures.
- Findings indicate that avoiding highly costly individuals can lead to modular networks, while favoring interactions with highly beneficial partners can result in less modular networks, highlighting the importance of individual decision-making in social trade-offs.
Article Synopsis
- Disgust is an evolved response aimed at reducing illness risk, linked to behaviors that help avoid parasites and toxins, but its role in wild animal disease avoidance is not well understood.
- With rising human-wildlife conflicts, understanding disgust is crucial for developing effective conservation strategies, utilizing modern tools in animal ecology for testing behaviors across various species and environments.
- The paper suggests five practical applications of disgust-related avoidance, emphasizes the need for comprehensive studies on disease and ecological interactions, discusses ethical considerations in research, and calls for a database to compile evidence on animal disease avoidance behaviors.
Article Synopsis
- Female primates, especially mothers, play a crucial role in the social development of their offspring, but their parenting styles can vary significantly, particularly in terms of protectiveness and rejection.
- This study observed two species of macaques with different dominance styles: the less tolerant Japanese macaques and the more tolerant moor macaques, to see how these styles influenced maternal behavior and offspring development.
- Findings indicated that maternal behaviors, such as proximity and grooming, changed differently as the offspring matured, with distinct impacts on the offspring's independent interactions and play based on their mother's style of care.
Article Synopsis
- Environmental contamination, particularly in wetlands, significantly contributes to biodiversity loss, impacting species during critical development phases.
- This study examined the effects of the herbicide nicosulfuron on spined toad tadpoles at various developmental stages, revealing that exposure led to larger size but altered body and tail muscle traits, increased activity, and changes in swimming speed and behavior.
- Results indicated that higher concentrations of the herbicide correlated with more significant effects, and that the timing of exposure did not change the outcomes, highlighting the importance for regulators to address sublethal concentrations in environmental policies.
Article Synopsis
- Group living can benefit individuals, but it also increases the risk of pathogen transmission due to more social contacts that lead to higher parasite abundance.
- The study focused on Japanese macaques to explore how social network centrality (connections and interactions) relates to gastrointestinal helminth infection intensity measured by egg counts in feces.
- The results indicated that while network centrality correlated with infection intensity at the whole group level, this correlation weakened and lost statistical significance when only subsets of the group were analyzed, suggesting that excluding parts of the population affects overall findings.
Article Synopsis
- The study explores how bacterial infections influence social behaviors in fruit flies, focusing on factors like pathogen species, dose, genetic background, and sex.
- Infected female flies showed reduced mean pairwise distance with each other, varying with the type of bacteria, while they did not avoid infected flies.
- There were also notable differences in social aggregation based on sex, with infected females gathering more closely than males, indicating that infection not only affects behavior but also has implications for disease transmission depending on genetic and sex-related factors.
Article Synopsis
- Parasites play a crucial role in ecosystems by affecting food chains, competition, and biodiversity, yet their complex interactions in nature remain poorly understood.
- In Southeast Asia, particularly in Borneo, habitat changes and wildlife circulation impact these relationships, making the study of primate parasites essential for understanding transmission processes.
- This research investigates the gastrointestinal helminth parasites in Bornean primates, revealing diverse and widespread parasitic infections, with new records for several primate species, highlighting significant gaps in our knowledge of primate-parasite dynamics in the region.
Article Synopsis
- * In three experiments, these macaques reacted to human gaze in different contexts (threat, cooperation, competition), showing varied behaviors based on the situation.
- * The findings suggest that macaques interpret human gaze contextually; they perceive direct gaze as threatening and respond to cooperative cues but appear unable to consider the perspective of a competitor.
Article Synopsis
- Rank among macaque species influences their access to food, with subordinate individuals needing specific strategies to secure resources, particularly in despotic species.* -
- In a study comparing three macaque species, tolerant species were more successful in obtaining food without relying on specific tactics, whereas despotic species required subordinates to use stealthy or opportunistic tactics.* -
- The findings indicate that the social hierarchy and dominance styles in macaque species predict the use of different food retrieval strategies, enhancing our understanding of tactical behaviors in social animals.*
Article Synopsis
- Primates exist in varied social systems with differing levels of dominance, affecting their social tolerance and access to resources, particularly food.
- The study focused on four macaque species and explored how their dominance styles influenced their willingness to try new foods (neophilia) and their social interactions around food.
- Results showed that higher dominance and social integration led to better access to food across species, and surprising patterns indicated that more despotic species exhibited higher social tolerance than less despotic ones, suggesting that individual traits may be more crucial than just dominance rank.
Article Synopsis
- Play behavior varies widely among mammalian species, influenced by their social structures and dominance hierarchies.
- A study comparing Japanese macaques and moor macaques revealed that less despotic species (moor macaques) engage in more frequent and varied play, while more despotic species (Japanese macaques) tend to display more grooming and aggressive interactions.
- The results suggest that social play and dominance style are linked, with the moor macaques showing greater engagement in playful activities and fewer aggressive escalations compared to the Japanese macaques.
Article Synopsis
- Social structure influences both the spread of information and the transmission of pathogens, affecting how individuals interact within a community.
- The relationship between information sharing and infection dynamics is often overlooked in studies of social evolution.
- An integrated approach is suggested to examine how social adaptability (phenotypic plasticity) can enhance information dissemination and manage pathogen spread.
Article Synopsis
- Changes in marine ecosystems are more easily observed in predators like seabirds since they connect different levels of the food web.
- A study on little penguins reveals that their diving behavior is affected by sea surface temperature and water stratification, impacting how efficiently they forage for food.
- Penguins foraging in warmer, stratified waters displayed more complex diving patterns and higher foraging efficiency, indicating they adapt their strategies based on environmental conditions.
Article Synopsis
- The study investigates the effects of different anaesthetic combinations on common marmosets, focusing on alfaxalone alone and in combination with ketamine and butorphanol-medetomidine.
- Seven female marmosets were treated with four different anaesthetic protocols, with varying durations of unresponsiveness observed after administration.
- The results indicate that the combination treatment (AMB) caused a more significant decrease in heart rate and oxygen levels, suggesting the need for careful monitoring and oxygen support when using this protocol.
Article Synopsis
- Parasites have historically influenced animal behavior, prompting adaptations like the avoidance of cues that signal their presence, particularly concerning faeces.
- This study focused on two primate species, mandrills and long-tailed macaques, to examine if their aversion to faeces during foraging is linked to visual and olfactory signals.
- Findings showed mandrills consumed less food and long-tailed macaques manipulated food more when exposed to faecal cues, aligning with the infection-avoidance hypothesis, indicating a need for further research on avoidance strategies in primates.
Article Synopsis
- Males of Enterobius serratus, a type of nematode, have been described for the first time based on samples collected from proboscis monkeys in Malaysia.
- These male nematodes share similar head structures with females but can be easily identified by their uniquely serrated lip edges.
- Notable features include a bicolored esophagus, a long thin reproductive structure called a spicule, and a developed spicular pouch with muscular bands, suggesting similarities with other Asian nematodes in this subgenus.
Article Synopsis
- Primates, including Japanese macaques, consume various plants not just for nutrition but also for medicinal purposes, especially to combat infections from parasites and pathogens.
- A 16-month study on Japanese macaques investigated their feeding habits and the ethnomedicinal potential of 45 plant extracts against important human parasites, as well as their toxicity on mammalian cells.
- The study found that 37% of the surveyed plants had ethnomedicinal uses for treating parasites and that most extracts showed significant activity against tested parasites, particularly against T. b. rhodesiense and P. falciparum.
Article Synopsis
- The study focuses on filling the knowledge gap regarding the hematology and blood chemistry of captive Japanese macaques, despite extensive research on their behavior and ecology.
- Researchers analyzed data from 511 hematological examinations and various blood chemistry tests conducted on healthy, retrovirus-free macaques between 2009 and 2013.
- The findings offer specific baseline hematological parameters for Japanese macaques, highlighting differences from other macaque species and noting variations based on age, sex, and origin, which can aid in clinical care for these animals.
Article Synopsis
- - Strongyles, specifically nodule worm species, are often underestimated in terms of their impact on both nonhuman primates and humans, despite their potential to cause serious disease.
- - The study investigates strongyles in Bornean primates, testing two hypotheses about parasite transmission based on genetic structure: high transmission vs. cryptic diversity.
- - Results show that the nodule worm infecting Asian nonhuman primates has little genetic variation, indicating high adaptability and potential gene flow among primate hosts, and emphasizing the need for studies on the zoonotic risks for nearby human populations.
A pinworm's tale: The evolutionary history of .
Liesbeth Frias Hideo Hasegawa Danica J Stark Milena Salgado Lynn Senthilvel Kss Nathan Andrew J J MacIntosh
Int J Parasitol Parasites Wildl
April 2019
Article Synopsis
- The study identifies a unique pinworm species that infects slow lorises, marking the first instance of such an infection outside Africa.
- A detailed comparison of male and female worms, along with fourth-stage larvae, was conducted in Sabah, Malaysian Borneo.
- The research indicates that this pinworm may be more closely related to those infecting Old World primates rather than those found in lemurs, suggesting a potential reclassification.
Lurking in the dark: Cryptic in a Bornean slow loris.
Liesbeth Frias Danica J Stark Milena Salgado Lynn Senthilvel Kss Nathan Benoit Goossens Andrew J J MacIntosh
Int J Parasitol Parasites Wildl
August 2018
Article Synopsis
- Researchers have found that closely related host species often share parasites, leading to the assumption that these parasites belong to a single species, but the genetic diversity of these parasites is not well understood.
- A study in Malaysian Borneo identified a case of a potentially new species of nematode infecting the Bornean slow loris, despite the presence of the same parasite genus in other primate species within the community.
- The findings suggest that there may be greater diversity among nematode species in primates than previously recognized, which could have important implications for understanding ecological and evolutionary relationships and the spread of diseases.