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Ecology and Evolution Jan 2023Fecundity, the number of young produced by a breeding pair during a breeding season, is a primary component in evolutionary and ecological theory and applications....
Fecundity, the number of young produced by a breeding pair during a breeding season, is a primary component in evolutionary and ecological theory and applications. Fecundity can be influenced by many environmental factors and requires long-term study due to the range of variation in ecosystem dynamics. Fecundity data often include a large proportion of zeros when many pairs fail to produce any young during a breeding season due to nest failure or when all young die independently after fledging. We conducted color banding and monthly censuses of Florida scrub-jays () across 31 years, 15 populations, and 761 territories along central Florida's Atlantic coast. We quantified how fecundity (juveniles/pair-year) was influenced by habitat quality, presence/absence of nonbreeders, population density, breeder experience, and rainfall, with a zero-inflated Bayesian hierarchical model including both a Bernoulli (e.g., brood success) and a Poisson (counts of young) submodel, and random effects for year, population, and territory. The results identified the importance of increasing "strong" quality habitat, which was a mid-successional state related to fire frequency and extent, because strong territories, and the proportion of strong territories in the overall population, influenced fecundity of breeding pairs. Populations subject to supplementary feeding also had greater fecundity. Territory size, population density, breeder experience, and rainfall surprisingly had no or small effects. Different mechanisms appeared to cause annual variation in fecundity, as estimates of random effects were not correlated between the success and count submodels. The increased fecundity for pairs with nonbreeders, compared to pairs without, identified empirical research needed to understand how the proportion of low-quality habitats influences population recovery and sustainability, because dispersal into low-quality habitats can drain nonbreeders from strong territories and decrease overall fecundity. We also describe how long-term study resulted in reversals in our understanding because of complications involving habitat quality, sociobiology, and population density.
PubMed: 36687801
DOI: 10.1002/ece3.9704 -
Insects Jan 2020Mushroom bodies (MBs) are multisensory integration centers in the insect brain involved in learning and memory formation. In the honeybee, the main sensory input region... (Review)
Review
Mushroom bodies (MBs) are multisensory integration centers in the insect brain involved in learning and memory formation. In the honeybee, the main sensory input region (calyx) of MBs is comparatively large and receives input from mainly olfactory and visual senses, but also from gustatory/tactile modalities. Behavioral plasticity following differential brood care, changes in sensory exposure or the formation of associative long-term memory (LTM) was shown to be associated with structural plasticity in synaptic microcircuits (microglomeruli) within olfactory and visual compartments of the MB calyx. In the same line, physiological studies have demonstrated that MB-calyx microcircuits change response properties after associative learning. The aim of this review is to provide an update and synthesis of recent research on the plasticity of microcircuits in the MB calyx of the honeybee, specifically looking at the synaptic connectivity between sensory projection neurons (PNs) and MB intrinsic neurons (Kenyon cells). We focus on the honeybee as a favorable experimental insect for studying neuronal mechanisms underlying complex social behavior, but also compare it with other insect species for certain aspects. This review concludes by highlighting open questions and promising routes for future research aimed at understanding the causal relationships between neuronal and behavioral plasticity in this charismatic social insect.
PubMed: 31936165
DOI: 10.3390/insects11010043 -
Communications Biology Nov 2022Converging lines of inquiry from across the social and biological sciences target the adult sex ratio (ASR; the proportion of males in the adult population) as a... (Review)
Review
Converging lines of inquiry from across the social and biological sciences target the adult sex ratio (ASR; the proportion of males in the adult population) as a fundamental population-level determinant of behavior. The ASR, which indicates the relative number of potential mates to competitors in a population, frames the selective arena for competition, mate choice, and social interactions. Here we review a growing literature, focusing on methodological developments that sharpen knowledge of the demographic variables underlying ASR variation, experiments that enhance understanding of the consequences of ASR imbalance across societies, and phylogenetic analyses that provide novel insights into social evolution. We additionally highlight areas where research advances are expected to make accelerating contributions across the social sciences, evolutionary biology, and biodiversity conservation.
Topics: Humans; Male; Animals; Adult; Sex Ratio; Phylogeny; Biological Evolution
PubMed: 36402823
DOI: 10.1038/s42003-022-04223-w -
Journal of Neurogenetics 2020The last few decades have seen the structural and functional elucidation of small-molecule chemical signals called ascarosides in . Ascarosides mediate several... (Review)
Review
The last few decades have seen the structural and functional elucidation of small-molecule chemical signals called ascarosides in . Ascarosides mediate several biological processes in worms, ranging from development, to behavior. These signals are modular in their design architecture, with their building blocks derived from metabolic pathways. Behavioral responses are not only concentration dependent, but also are influenced by the current physiological state of the animal. Cellular and circuit-level analyses suggest that these signals constitute a complex communication system, employing both synergistic molecular elements and sex-specific neuronal circuits governing the response. In this review, we discuss research from multiple laboratories, including our own, that detail how these chemical signals govern several different social behaviors in We propose that the ascaroside repertoire represents a link between diverse metabolic and neurobiological life-history traits and governs the survival of in its natural environment.
Topics: Adaptation, Physiological; Animals; Caenorhabditis elegans; Chemoreceptor Cells; Dose-Response Relationship, Drug; Female; Genes, Helminth; Glycolipids; Hermaphroditic Organisms; Locomotion; Male; Metabolic Networks and Pathways; Molecular Structure; Nematoda; Neural Pathways; Pheromones; Sex Attractants; Sexual Behavior, Animal; Signal Transduction; Social Behavior; Starvation
PubMed: 32990104
DOI: 10.1080/01677063.2020.1808634 -
Frontiers in Psychology 2020Comparative psychology assesses cognitive abilities and capacities of non-human animals and humans. Based on performance differences and similarities in various species... (Review)
Review
Comparative psychology assesses cognitive abilities and capacities of non-human animals and humans. Based on performance differences and similarities in various species in cognitive tests, it is inferred how their minds work and reconstructed how cognition might have evolved. Critically, such species comparisons are only valid and meaningful if the tasks truly capture individual and inter-specific variation in cognitive abilities rather than contextual variables that might affect task performance. Unlike in human test psychology, however, cognitive tasks for non-human primates (and most other animals) have been rarely evaluated regarding their measurement validity. We review recent studies that address how non-cognitive factors affect performance in a set of commonly used cognitive tasks, and if cognitive tests truly measure individual variation in cognitive abilities. We find that individual differences in emotional and motivational factors primarily affect performance via attention. Hence, it is crucial to systematically control for attention during cognitive tasks to obtain valid and reliable results. Aspects of test design, however, can also have a substantial effect on cognitive performance. We conclude that non-cognitive factors are a minor source of measurement error if acknowledged and properly controlled for. It is essential, however, to validate and eventually re-design several primate cognition tasks in order to ascertain that they capture the cognitive abilities they were designed to measure. This will provide a more solid base for future cognitive comparisons within primates but also across a wider range of non-human animal species.
PubMed: 32982822
DOI: 10.3389/fpsyg.2020.01835 -
Primates; Journal of Primatology May 2020Over the past 20 years, GPS collars have emerged as powerful tools for the study of nonhuman primate (hereafter, "primate") movement ecology. As the size and cost of GPS... (Review)
Review
Over the past 20 years, GPS collars have emerged as powerful tools for the study of nonhuman primate (hereafter, "primate") movement ecology. As the size and cost of GPS collars have decreased and performance has improved, it is timely to review the use and success of GPS collar deployments on primates to date. Here we compile data on deployments and performance of GPS collars by brand and examine how these relate to characteristics of the primate species and field contexts in which they were deployed. The compiled results of 179 GPS collar deployments across 17 species by 16 research teams show these technologies can provide advantages, particularly in adding to the quality, quantity, and temporal span of data collection. However, aspects of this technology still require substantial improvement in order to make deployment on many primate species pragmatic economically. In particular, current limitations regarding battery lifespan relative to collar weight, the efficacy of remote drop-off mechanisms, and the ability to remotely retrieve data need to be addressed before the technology is likely to be widely adopted. Moreover, despite the increasing utility of GPS collars in the field, they remain substantially more expensive than VHF collars and tracking via handheld GPS units, and cost considerations of GPS collars may limit sample sizes and thereby the strength of inferences. Still, the overall high quality and quantity of data obtained, combined with the reduced need for on-the-ground tracking by field personnel, may help defray the high equipment cost. We argue that primatologists armed with the information in this review have much to gain from the recent, substantial improvements in GPS collar technology.
Topics: Animals; Ecology; Geographic Information Systems; Movement; Primates
PubMed: 31965380
DOI: 10.1007/s10329-020-00793-7 -
Behavioral Ecology and Sociobiology Dec 2014Senescence, the decline in physiological and behavioral function with increasing age, has been the focus of significant theoretical and empirical research in a broad...
Senescence, the decline in physiological and behavioral function with increasing age, has been the focus of significant theoretical and empirical research in a broad array of animal taxa. Preeminent among invertebrate social models of aging are ants, a diverse and ecologically dominant clade of eusocial insects characterized by reproductive and sterile phenotypes. In this review, we critically examine selection for worker lifespan in ants and discuss the relationship between functional senescence, longevity, task performance, and colony fitness. We did not find strong or consistent support for the hypothesis that demographic senescence in ants is programmed, or its corollary prediction that workers that do not experience extrinsic mortality die at an age approximating their lifespan in nature. We present seven hypotheses concerning how selection could favor extended worker lifespan through its positive relationship to colony size and predict that large colony size, under some conditions, should confer multiple and significant fitness advantages. Fitness benefits derived from long worker lifespan could be mediated by increased resource acquisition, efficient division of labor, accuracy of collective decision-making, enhanced allomaternal care and colony defense, lower infection risk, and decreased energetic costs of workforce maintenance. We suggest future avenues of research to examine the evolution of worker lifespan and its relationship to colony fitness, and conclude that an innovative fusion of sociobiology, senescence theory, and mechanistic studies of aging can improve our understanding of the adaptive nature of worker lifespan in ants.
PubMed: 25530660
DOI: 10.1007/s00265-014-1826-4 -
Research in Microbiology 2020Twentieth century observed a huge paradigm shift in the field of sociobiology, which moved from social intelligence of animals to microbes. Quorum Sensing Molecules... (Review)
Review
Twentieth century observed a huge paradigm shift in the field of sociobiology, which moved from social intelligence of animals to microbes. Quorum Sensing Molecules (QSMs) are the small chemical molecules, which establish the mode of communication among microbes, and is called Quorum Sensing (QS). These molecules are crucial for determining the decisions of large groups of cells, which is a density-dependent process. Thus, this mechanism draws a very thin line between bacteria that are actually prokaryotes and clustered bacteria mimicking eukaryotes. This review discusses about the designs of microbial communication networks, and the role of QS in plant-microbe interaction.
Topics: Acyl-Butyrolactones; Endophytes; Fungi; Gram-Negative Bacteria; Gram-Positive Bacteria; Microbial Interactions; Plants; Quorum Sensing
PubMed: 32592751
DOI: 10.1016/j.resmic.2020.06.003 -
Proceedings of the National Academy of... Oct 2022Knowledge on the distribution and abundance of organisms is fundamental to understanding their roles within ecosystems and their ecological importance for other taxa....
Knowledge on the distribution and abundance of organisms is fundamental to understanding their roles within ecosystems and their ecological importance for other taxa. Such knowledge is currently lacking for insects, which have long been regarded as the "little things that run the world". Even for ubiquitous insects, such as ants, which are of tremendous ecological significance, there is currently neither a reliable estimate of their total number on Earth nor of their abundance in particular biomes or habitats. We compile data on ground-dwelling and arboreal ants to obtain an empirical estimate of global ant abundance. Our analysis is based on 489 studies, spanning all continents, major biomes, and habitats. We conservatively estimate total abundance of ground-dwelling ants at over 3 × 10 and estimate the number of all ants on Earth to be almost 20 × 10 individuals. The latter corresponds to a biomass of ∼12 megatons of dry carbon. This exceeds the combined biomass of wild birds and mammals and is equivalent to ∼20% of human biomass. Abundances of ground-dwelling ants are strongly concentrated in tropical and subtropical regions but vary substantially across habitats. The density of leaf-litter ants is highest in forests, while the numbers of actively ground-foraging ants are highest in arid regions. This study highlights the central role ants play in terrestrial ecosystems but also major ecological and geographic gaps in our current knowledge. Our results provide a crucial baseline for exploring environmental drivers of ant-abundance patterns and for tracking the responses of insects to environmental change.
Topics: Animal Distribution; Animals; Ants; Biomass; Earth, Planet; Ecosystem; Humans; Mammals; Population Density
PubMed: 36122199
DOI: 10.1073/pnas.2201550119 -
Berichte Zur Wissenschaftsgeschichte Jun 2022As soon as ethology's status diminished in the early 1970s, it was confronted with two successor disciplines, sociobiology and behavioral ecology. They were able to...
As soon as ethology's status diminished in the early 1970s, it was confronted with two successor disciplines, sociobiology and behavioral ecology. They were able to challenge ethology because it no longer provided markers of strong disciplinarity such as theoretical coherence, leading figures and a clear identity. While behavioral ecology developed organically out of the UK ethological research community into its own disciplinary standing, sociobiology presented itself as a US competitor to the ethological tradition. I will show how behavioral ecology took the role of legitimate heir to ethology by rebuilding a theoretical core and an intellectual sense of community, while sociobiology failed to use its public appeal to reach disciplinary status. Meanwhile, ethology changed its disciplinary identity to encompass all biological studies of animal behavior.
Topics: Animals; Behavior, Animal; Ecology; Emotions; Ethology; Sociobiology
PubMed: 35467771
DOI: 10.1002/bewi.202200002