Do differences in ecological conditions influence grouping behaviour in a solitary ungulate, the Japanese serow?

Behaviour ◽  
2019 ◽  
Vol 156 (3-4) ◽  
pp. 245-264 ◽  
Author(s):  
H. Takada ◽  
M. Minami
Keyword(s):  
Group Size ◽  
Habitat Structure ◽  
Alpine Meadow ◽  
Resource Competition ◽  
Food Resource ◽  
Ecological Factors ◽  
Ecological Conditions ◽  
Evolution Of Sociality ◽  
Japanese Serow ◽  
The Cost

Abstract One aim of animal behaviour research is to explain why animals live in groups. The grouping behaviour of solitary mammals is important for understanding the ecological factors promoting the evolution of sociality. We present field data of Japanese serow, a primitive solitary ungulate, in forest and alpine meadow habitats. We found no differences in group size of all age–sex classes between the forest and alpine meadow habitats, and both populations were mainly solitary. The current findings suggest that group size in the serow is not affected by ecological conditions, including habitat structure, forage abundance, and population density. However, female associations involving up to three females occurred in the alpine meadow habitat throughout the year, whereas such groupings were not observed in the forest habitat. This finding suggests that abundant food supply in the alpine meadow promoted female associations by decreasing the cost of food resource competition.

scholarly journals Women’s Preferences for Strong Men Under Perceived Harsh Versus Safe Ecological Conditions

2021 ◽  
Vol 19 (3) ◽  
pp. 147470492110323
Author(s):  
Ray Garza ◽  
Farid Pazhoohi ◽  
Jennifer Byrd-Craven
Keyword(s):  
Ecological Factors ◽  
Ecological Condition ◽  
Sex Characteristics ◽  
Ecological Conditions ◽  
University Women ◽  
Secondary Sex Characteristics ◽  
Trade Offs ◽  
Forced Choice Task ◽  
Women’S Preferences ◽  
Physical Features

Ecological conditions provide information about available resources for one’s environment. In humans, this has been shown to influence reproductive behavior, as individuals may engage in trade-offs between partner quality and investment. For instance, many women may trade-off preferences for men with physical features indicative of social dominance and health over physical features indicative of commitment and investment. The current study explored women’s preferences for formidable men under safe vs. harsh ecological conditions. Across three studies, U.S. university women ( N = 1,098) were randomly assigned to a perceived harsh or safe ecological condition. They were asked to rate the attractiveness of men’s body types (i.e., muscular vs. less muscular). Findings revealed that in general, women rated stronger men as more attractive than weaker men irrespective of the ecological condition. Evidence for preference as a function of ecology appeared only when a two-alternative forced-choice task was used (Study 3), but not in rating tasks (Studies 1 and 2). Study 3 showed that women had a relatively stronger preference for stronger men for short-term relationships in a resource scarce ecological condition. This research provides some evidence that perceived ecological conditions can drive women’s preferences for men with enhanced secondary sex characteristics as a function of mating context. These findings are consistent with previous research indicating the importance of physical characteristics in men’s attractiveness, and it adds to the existing literature on ecological factors and mating preferences.

scholarly journals Group size and aquatic vegetation modulates male preferences for female shoals in wild zebrafish, Danio rerio

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Aditya Ghoshal ◽  
Anuradha Bhat
Keyword(s):  
Group Size ◽  
Aquatic Vegetation ◽  
Natural Habitat ◽  
Ecological Factors ◽  
Choice Test ◽  
Female Group ◽  
Aquatic Flora ◽  
In The Wild ◽  
The Individual

AbstractShoaling decisions in the wild are determined by a combination of innate preferences of the individual along with the interplay of multiple ecological factors. In their natural habitat as well as in the laboratory, zebrafish is a shoaling fish. Here, we investigate the role of group size and associated vegetation in shaping shoaling preferences of wild male zebrafish. We studied the association preference of males to groups of female shoals in a multi-choice test design. We found that males made greater proportion of visits to an 8-female group compared to 2 and 4-female groups. However, males spent similar proportions of time across the three female-containing groups. When artificial vegetation was incorporated along with female number as an additional factor, we found that males prefer high and moderately vegetated patches compared to low or no-vegetation groups, irrespective of the number of females in these patches. Based on experiments using a novel multi-choice design, our results show that preference for group size can change due to interaction of two separate factors. This work is a first attempt to understand the role of aquatic flora in determining shoaling preferences in zebrafish, using an experimental paradigm consisting of a gradation in female and vegetation densities.

scholarly journals Prey synchronize their vigilant behaviour with other group members

2007 ◽  
Vol 274 (1615) ◽  
pp. 1287-1291 ◽  
Author(s):  
Olivier Pays ◽  
Pierre-Cyril Renaud ◽  
Patrice Loisel ◽  
Maud Petit ◽  
Jean-François Gerard ◽  
...  
Keyword(s):  
Predation Risk ◽  
Group Size ◽  
Prey Species ◽  
Group Members ◽  
The Individual ◽  
The Cost ◽  
Group Member

It is generally assumed that an individual of a prey species can benefit from an increase in the number of its group's members by reducing its own investment in vigilance. But what behaviour should group members adopt in relation to both the risk of being preyed upon and the individual investment in vigilance? Most models assume that individuals scan independently of one another. It is generally argued that it is more profitable for each group member owing to the cost that coordination of individual scans in non-overlapping bouts of vigilance would require. We studied the relationships between both individual and collective vigilance and group size in Defassa waterbuck, Kobus ellipsiprymnus defassa , in a population living under a predation risk. Our results confirmed that the proportion of time an individual spent in vigilance decreased with group size. However, the time during which at least one individual in the group scanned the environment (collective vigilance) increased. Analyses showed that individuals neither coordinated their scanning in an asynchronous way nor scanned independently of one another. On the contrary, scanning and non-scanning bouts were synchronized between group members, producing waves of collective vigilance. We claim that these waves are triggered by allelomimetic effects i.e. they are a phenomenon produced by an individual copying its neighbour's behaviour.

Influence of desiccation, predatory cues, and density on metamorphic traits of the bronze frog Hylarana temporalis

2016 ◽  
Vol 37 (2) ◽  
pp. 199-205 ◽  
Author(s):  
Santosh Mogali ◽  
Srinivas Saidapur ◽  
Bhagyashri Shanbhag
Keyword(s):  
Ecological Factors ◽  
Larval Period ◽  
Ecological Factor ◽  
Water Quantity ◽  
Predation Threat ◽  
Predator Pressure ◽  
Size At Metamorphosis ◽  
The Cost ◽  
Pantala Flavescens

We conducted an experiment to understand the influence of ecological factors (desiccation, predation threat and density) on two major metamorphic traits, larval period and size at metamorphosis, in the Indian bronze frog,Hylarana temporalis. Tadpoles were reared in groups of 15 (low), 30 (medium) and 60 (high) densities. We created the threat of desiccation by removing 0.5 l water at 10 days intervals until the water quantity reached 0.5 l. Caged dragonfly larvae (Pantala flavescens) provided the predation threat. Results show that each ecological factor independently influenced metamorphic traits but not in an interactive way. Under desiccation threat the tadpoles metamorphosed earlier and at smaller sizes compared to those reared in constant water (at corresponding densities) regardless of presence/absence of predator. In contrast, under predation threat, tadpoles metamorphosed early and at a bigger size than those reared without predator regardless of density of rearing, and desiccation threat. Alternatively, an increase in density of rearing delayed metamorphosis with smaller metamorphic size in constant water and also under threat of desiccation regardless of whether predation threat existed or not. Thus, our study revealed thatH. temporalistadpoles can modify their response to each ecological factor regardless of what other factors operate simultaneously; the threat of desiccation shortens larval period at the cost of growth. Whereas, predator pressure shortens larval period along with increased growth; while greater density increases larval period and slows down growth inH. temporalis.

scholarly journals The interactive effects of competition and predation risk on dispersal in an insect

2014 ◽  
Vol 10 (6) ◽  
pp. 20140287 ◽  
Author(s):  
Celina B. Baines ◽  
Shannon J. McCauley ◽  
Locke Rowe
Keyword(s):  
Predation Risk ◽  
Intraspecific Competition ◽  
Aquatic Insects ◽  
Ecological Factors ◽  
Factorial Experiment ◽  
Interactive Effects ◽  
Factorial Experiments ◽  
Evolutionary Processes ◽  
Factors Affecting ◽  
Ecological Conditions

Dispersal dynamics have significant consequences for ecological and evolutionary processes. Previous work has demonstrated that dispersal can be context-dependent. However, factors affecting dispersal are typically considered in isolation, despite the probability that individuals make dispersal decisions in response to multiple, possibly interacting factors. We examined whether two ecological factors, predation risk and intraspecific competition, have interactive effects on dispersal dynamics. We performed a factorial experiment in mesocosms using backswimmers ( Notonecta undulata ), flight-capable, semi-aquatic insects. Emigration rates increased with density, and increased with predation risk at intermediate densities; however, predation had minimal effects on emigration at high and low densities. Our results indicate that factorial experiments may be required to understand dispersal dynamics under realistic ecological conditions.

scholarly journals What makes Hemidactylus invasions successful? A case study on the island of Curaçao

2020 ◽  
Author(s):  
April D. Lamb ◽  
Catherine A. Lippi ◽  
Gregory J. Watkins-Colwell ◽  
Andrew Jones ◽  
Dan Warren ◽  
...  
Keyword(s):  
Urban Areas ◽  
Resource Competition ◽  
Food Resource ◽  
Stomach Contents ◽  
Western Hemisphere ◽  
Morphometric Analyses ◽  
Close Proximity ◽  
Reptile Species ◽  
Prey Resources ◽  
Hemidactylus Mabouia

AbstractHemidactylus spp. (House geckos) rank among the most successful invasive reptile species worldwide. Hemidactylus mabouia in particular has become ubiquitous across tropical urban settings in the Western Hemisphere. H. mabouia’s ability to thrive in close proximity to humans has led to the rapid displacement of native geckos in urban areas, however the mechanisms driving this displacement remain understudied. Here we combine data from nitrogen and carbon stable isotopes, stomach contents, and morphometric analyses of traits associated with feeding and locomotion to test alternate hypotheses of displacement between H. mabouia and a native gecko, Phyllodactylus martini, on the island of Curaçao. Consistent with expectations of direct food resource competition, we demonstrate substantial overlap of invertebrate prey resources between the species. Additionally, we found strong evidence from both diet content and stable isotope analyses that H. mabouia acts as a vertebrate predator, preying upon P. martini as well as other native and non-native reptiles. Finally, we show that H. mabouia possesses several morphological advantages, including larger sizes in feeding-associated traits and limb proportions that could offer a propulsive locomotor advantage on vertical surfaces. Together, these findings suggest the successful establishment of H. mabouia likely involves a combination of both exploitative interspecific competition and predation. Given the ubiquity of H. mabouia, illuminating the role of this species as both a competitor and a predator casts new concerns on the ecological and demographic impacts of this widespread urban invader.

scholarly journals Ecological and dietary differences between Ugandan chimpanzee communities with possible implications on tool use

2019 ◽  
Author(s):  
Iris Berger ◽  
Catherine Hobaiter ◽  
Matthew Bell ◽  
Delphine De Moor ◽  
Thibaud Gruber
Keyword(s):  
Food Availability ◽  
Tool Use ◽  
Ecological Factors ◽  
The Other ◽  
Small Scale ◽  
Home Ranges ◽  
Ecological Conditions ◽  
Food Diversity ◽  
Faecal Samples ◽  
Budongo Forest

ABSTRACTSome East African chimpanzee (Pan troglodytes schweinfurthii) communities, such as the Sonso chimpanzees, display an unusually limited range of tool-use, but it remains unclear whether this is due to ecological and/or cultural factors. Information on ecological conditions and the diet of the Sonso chimpanzees in relation to neighbouring communities is needed. Here, we studied three adjacent communities in Budongo Forest (Sonso, Waibira, and Kamira), and the presumed core area of an undescribed community (Mwera), in the neighbouring Bugoma Forest. Through line-transects, we investigated (i) whether there were differences in food diversity and abundance between the communities’ home ranges; (ii) whether the home ranges differed in abundance of sticks and insect nests; and (iii) whether Sonso and Mwera chimpanzees differed in their diet (using faecal samples). Across communities, Sonso had the richest food availability and the lowest insect nest abundance. However, food availability in Mwera, Bugoma, was richer than Budongo communities that neighbour the Sonso territory, suggesting that there may be variation within Budongo. Data from faecal samples replicated our direct observations of food availability suggesting that Sonso chimpanzees had a broader diet than Mwera chimpanzees. This difference in foods availability may partially explain the Sonso chimpanzees’ lack of stick-tool-use, and low levels of insectivory. The tool repertoire of the other communities is currently unknown; however, we make predictions based on our ecological data. More detailed knowledge of small-scale variation in ecology within and between forest habitats may be important to advancing our understanding of the drivers of tool-use.SIGNIFICANCE STATEMENT – HIGHLIGHTED STUDENT PAPERTo advance our knowledge of the role of ecological factors in the emergence of tool use in chimpanzees, a nuanced understanding of the ecological conditions different chimpanzee communities experience is needed. We studied four Ugandan chimpanzee communities in two forests. One of these communities, Sonso, in the Budongo Forest, is well-known for its restricted range of tool types, including a total absence of stick use. Food diversity and abundance were highest, and stick tool use opportunities (abundance of sticks and insect nests) were lowest for the core-habitat of the Sonso chimpanzees in contrast to the other communities. We argue that ecological factors play a role in their unusual pattern of tool use, and make predictions about the expected types of tool use in the other communities based on their ecology. Thus, our study provides information that may help advance our understanding of how tool use arises under varied socioecological circumstances.

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