scholarly journals Fractal geometry of a complex plumage trait reveals bird's quality

2013 ◽  
Vol 280 (1755) ◽  
pp. 20122783 ◽  
Author(s):  
Lorenzo Pérez-Rodríguez ◽  
Roger Jovani ◽  
François Mougeot
Keyword(s):  
Body Condition ◽  
Fractal Geometry ◽  
Animal Communication ◽  
Alectoris Rufa ◽  
Colour Intensity ◽  
Colour Patterns ◽  
Behaviour Genetics ◽  
Natural And Sexual Selection ◽  
Individual Body ◽  
Study Species

Animal coloration is key in natural and sexual selection, playing significant roles in intra- and interspecific communication because of its linkage to individual behaviour, genetics and physiology. Simple animal traits such as the area or the colour intensity of homogeneous patches have been profusely studied. More complex patterns are widespread in nature, but they escape our understanding because their variation is difficult to capture effectively by standard, simple measures. Here, we used fractal geometry to quantify inter-individual variation in the expression of a complex plumage trait, the heterogeneous black bib of the red-legged partridge ( Alectoris rufa ). We show that a higher bib fractal dimension (FD) predicted better individual body condition, as well as immune responsiveness, which is condition-dependent in our study species. Moreover, when food intake was experimentally reduced during moult as a means to reduce body condition, the bib's FD significantly decreased. Fractal geometry therefore provides new opportunities for the study of complex animal colour patterns and their roles in animal communication.

Phenotypic differences in body size, body condition and circulating carotenoids between hybrid and “pure” red-legged partridges (Alectoris rufa) in the wild

2013 ◽  
Vol 154 (3) ◽  
pp. 803-811 ◽  
Author(s):  
F. Casas ◽  
F. Mougeot ◽  
M. E. Ferrero ◽  
I. Sánchez-Barbudo ◽  
J. A. Dávila ◽  
...  
Keyword(s):  
Body Size ◽  
Body Condition ◽  
Alectoris Rufa ◽  
Phenotypic Differences ◽  
In The Wild

scholarly journals Sexual deception in a cannibalistic mating system? Testing the Femme Fatale hypothesis

2015 ◽  
Vol 282 (1800) ◽  
pp. 20141428 ◽  
Author(s):  
Katherine L. Barry
Keyword(s):  
Mating System ◽  
Body Condition ◽  
Communication Theory ◽  
Animal Communication ◽  
Femme Fatale ◽  
Mate Searching ◽  
Sexual Deception ◽  
Honest Signalling ◽  
Food Quantity ◽  
Praying Mantid

Animal communication theory holds that in order to be evolutionarily stable, signals must be honest on average, but significant dishonesty (i.e. deception) by a subset of the population may also evolve. A typical praying mantid mating system involves active mate searching by males, which is guided by airborne sex pheromones in most species for which mate-searching cues have been studied. The Femme Fatale hypothesis suggests that female mantids may be selected to exploit conspecific males as prey if they benefit nutritionally from cannibalism. Such a benefit exists in the false garden mantid Pseudomantis albofimbriata —females use the resources gained from male consumption to significantly increase their body condition and reproductive output. This study aimed to examine the potential for chemical deception among the subset of females most likely to benefit from cannibalism (poorly fed females). Females were placed into one of four feeding treatments (‘Very Poor’, ‘Poor’, ‘Medium’ and ‘Good’), and males were given the opportunity to choose between visually obscured females in each of the treatments. Female body condition and fecundity varied linearly with food quantity; however, female attractiveness did not. That is, Very Poor females attracted significantly more males than any of the other female treatments, even though these females were in significantly poorer condition, less fecund (in this study) and more likely to cannibalise (in a previous study). In addition, there was a positive correlation between fecundity and attractiveness if Very Poor females were removed from the analysis, suggesting an inherently honest signalling system with a subset of dishonest individuals. This is the first empirical study to provide evidence of sexual deception via chemical cues, and the first to provide support for the Femme Fatale hypothesis.

scholarly journals Concerted variation in melanogenesis genes underlies emergent patterning of plumage in capuchino seedeaters

2022 ◽  
Vol 289 (1966) ◽  
Author(s):  
Cecilia Estalles ◽  
Sheela P. Turbek ◽  
María José Rodríguez-Cajarville ◽  
Luís Fábio Silveira ◽  
Kazumasa Wakamatsu ◽  
...  
Keyword(s):  
Animal Communication ◽  
The Body ◽  
Body Parts ◽  
Genetic Changes ◽  
Association Analyses ◽  
Colour Variation ◽  
Genomic Changes ◽  
Colour Patterns ◽  
Coloration Patterns ◽  
Genomic Regions

Coloration traits are central to animal communication; they often govern mate choice, promote reproductive isolation and catalyse speciation. Specific genetic changes can cause variation in coloration, yet far less is known about how overall coloration patterns—which involve combinations of multiple colour patches across the body—can arise and are genomically controlled. We performed genome-wide association analyses to link genomic changes to variation in melanin (eumelanin and pheomelanin) concentration in feathers from different body parts in the capuchino seedeaters, an avian radiation with diverse colour patterns despite remarkably low genetic differentiation across species. Cross-species colour variation in each plumage patch is associated with unique combinations of variants at a few genomic regions, which include mostly non-coding (presumably regulatory) areas close to known pigmentation genes. Genotype–phenotype associations can vary depending on patch colour and are stronger for eumelanin pigmentation, suggesting eumelanin production is tightly regulated. Although some genes are involved in colour variation in multiple patches, in some cases, the SNPs associated with colour changes in different patches segregate spatially. These results suggest that coloration patterning in capuchinos is generated by the modular combination of variants that regulate multiple melanogenesis genes, a mechanism that may have promoted this rapid radiation.

scholarly journals Gut microbiome composition, not alpha diversity, is associated with survival in a natural vertebrate population

2021 ◽  
Vol 3 (1) ◽  
Author(s):  
Sarah F. Worsley ◽  
Charli S. Davies ◽  
Maria-Elena Mannarelli ◽  
Matthew I. Hutchings ◽  
Jan Komdeur ◽  
...  
Keyword(s):  
Natural Population ◽  
Breeding Season ◽  
Body Condition ◽  
Gut Microbiome ◽  
Alpha Diversity ◽  
Host Fitness ◽  
Community Membership ◽  
Long Term Study ◽  
In The Wild ◽  
Individual Body

Abstract Background The vertebrate gut microbiome (GM) can vary substantially across individuals within the same natural population. Although there is evidence linking the GM to health in captive animals, very little is known about the consequences of GM variation for host fitness in the wild. Here, we explore the relationship between faecal microbiome diversity, body condition, and survival using data from the long-term study of a discrete natural population of the Seychelles warbler (Acrocephalus sechellensis) on Cousin Island. To our knowledge, this is the first time that GM differences associated with survival have been fully characterised for a natural vertebrate species, across multiple age groups and breeding seasons. Results We identified substantial variation in GM community structure among sampled individuals, which was partially explained by breeding season (5% of the variance), and host age class (up to 1% of the variance). We also identified significant differences in GM community membership between adult birds that survived, versus those that had died by the following breeding season. Individuals that died carried increased abundances of taxa that are known to be opportunistic pathogens, including several ASVs in the genus Mycobacterium. However, there was no association between GM alpha diversity (the diversity of bacterial taxa within a sample) and survival to the next breeding season, or with individual body condition. Additionally, we found no association between GM community membership and individual body condition. Conclusions These results demonstrate that components of the vertebrate GM can be associated with host fitness in the wild. However, further research is needed to establish whether changes in bacterial abundance contribute to, or are only correlated with, differential survival; this will add to our understanding of the importance of the GM in the evolution of host species living in natural populations.

Recovery of southern bent-winged bats (Miniopterus orianae bassanii) after PIT-tagging and the use of surgical adhesive

2020 ◽  
Vol 42 (2) ◽  
pp. 216
Author(s):  
Emmi van Harten ◽  
Terry Reardon ◽  
Peter H. Holz ◽  
Ruth Lawrence ◽  
Thomas A. A. Prowse ◽  
...  
Keyword(s):  
Injection Site ◽  
Body Condition ◽  
Small Mammals ◽  
Skin Irritation ◽  
Pit Tags ◽  
Surgical Adhesive ◽  
Good Body Condition ◽  
Pit Tagging ◽  
The Impact ◽  
Study Species

Surgical adhesive is widely used to prevent shedding of injected PIT-tags, but the effect of this adhesive on individuals has not been documented. We recaptured 52 southern bent-winged bats up to 741 days after PIT-tagging. All recaptured individuals were in good body condition, with no signs of infection or skin irritation; however, temporary fur loss occurred at the injection site. We advocate that researchers consider the impact this may have on study species, particularly when PIT-tagging small mammals during cooler months.

Condition Dependence of Structural Plumage Coverage in Indigo Buntings Passerina Cyanea

2018 ◽  
Vol 11 (1) ◽  
pp. 54-61 ◽  
Author(s):  
Spencer B. Hudson ◽  
Travis E. Wilcoxen
Keyword(s):  
Body Condition ◽  
Blood Parasites ◽  
Condition Dependence ◽  
Innate Immune Responses ◽  
Testosterone Levels ◽  
Plumage Colouration ◽  
Passerina Cyanea ◽  
Dependent Signal ◽  
Sexual Characteristic ◽  
Study Species

Nuptial plumage colouration is seemingly favoured by females of avian species with regards to sexual selection. This particular secondary sexual characteristic has been previously shown to be a condition-dependent signal of individual quality among passerines with pigment-based colouration (i.e. yellows and reds). In contrast, relationships between structural plumage colouration (i.e. blues) and aspects of both physical quality and physiological function have been understudied. Using free-living Indigo Buntings (Passerina cyanea) as a study species, we compared the percentage of blue feather coverage to body condition, innate immune responses, antioxidant capacity, stress physiology, reproductive physiology, and parasitism. We found the overall percentage of blue feathers on individual birds to be positively correlated with testosterone levels and body condition, while negatively correlated with heterophil to lymphocyte ratio. Birds with more blue coverage were also less likely to harbour blood parasites. Our results indicate male Indigo Buntings with greater moult investment have better overall body condition, lower stress, increased testosterone levels, and decreased parasitic susceptibility.

scholarly journals Shape matters: animal colour patterns as signals of individual quality

2017 ◽  
Vol 284 (1849) ◽  
pp. 20162446 ◽  
Author(s):  
Lorenzo Pérez-Rodríguez ◽  
Roger Jovani ◽  
Martin Stevens
Keyword(s):  
Multidisciplinary Approach ◽  
Potential Role ◽  
Evolutionary Developmental Biology ◽  
Research Area ◽  
Individual Quality ◽  
Colour Intensity ◽  
Model Species ◽  
Future Challenges ◽  
Colour Patterns ◽  
Pattern Variability

Colour patterns (e.g. irregular, spotted or barred forms) are widespread in the animal kingdom, yet their potential role as signals of quality has been mostly neglected. However, a review of the published literature reveals that pattern itself (irrespective of its size or colour intensity) is a promising signal of individual quality across species of many different taxa. We propose at least four main pathways whereby patterns may reliably reflect individual quality: (i) as conventional signals of status, (ii) as indices of developmental homeostasis, (iii) by amplifying cues of somatic integrity and (iv) by amplifying individual investment in maintenance activities. Methodological constraints have traditionally hampered research on the signalling potential of colour patterns. To overcome this, we report a series of tools (e.g. colour adjacency and pattern regularity analyses, Fourier and granularity approaches, fractal geometry, geometric morphometrics) that allow objective quantification of pattern variability. We discuss how information provided by these methods should consider the visual system of the model species and behavioural responses to pattern metrics, in order to allow biologically meaningful conclusions. Finally, we propose future challenges in this research area that will require a multidisciplinary approach, bringing together inputs from genetics, physiology, behavioural ecology and evolutionary-developmental biology.

scholarly journals Environmental effects and individual body condition drive seasonal fecundity of rabbits: identifying acute and lagged processes

Oecologia ◽  
2016 ◽  
Vol 181 (3) ◽  
pp. 853-864 ◽  
Author(s):  
Konstans Wells ◽  
Robert B. O’Hara ◽  
Brian D. Cooke ◽  
Greg J. Mutze ◽  
Thomas A. A. Prowse ◽  
...  
Keyword(s):  
Body Condition ◽  
Environmental Effects ◽  
Seasonal Fecundity ◽  
Individual Body

Are commonly used metrics of bird song complexity concordant?

The Auk ◽  
2019 ◽  
Vol 136 (1) ◽  
Author(s):  
Lauryn Benedict ◽  
Nadje A Najar
Keyword(s):  
Animal Communication ◽  
Single Species ◽  
Bird Song ◽  
Single Word ◽  
Bird Songs ◽  
Multiple Features ◽  
Song Complexity ◽  
Selective Pressures ◽  
Signal Complexity ◽  
Study Species

Abstract Researchers studying the evolution of animal communication often ask what generates and maintains signal complexity, but they define and measure complexity in different ways. If different metrics are not concordant, then studies using them are probably not comparable. In this study, we asked whether 7 metrics of bird song complexity vary in tandem among individuals of a single species, the Rock Wren (Salpinctes obsoletus). The included metrics were chosen because they are regularly used by researchers in the field to test hypotheses within the literature. Results indicated that none of the metrics positively correlated with any others, suggesting that bird songs are not under general selective pressures favoring increased complexity across multiple features. If metrics of signal complexity are not correlated, then care should be taken when designing analyses and comparing results. Researchers should always clearly define the “complexity” under investigation and verify that it has significance to the study species. Contradictory outcomes among existing research into signal “complexity” may result from the fact that this single word is used to represent multiple independent traits.

scholarly journals Gut microbiome composition, not alpha diversity, is associated with survival in a natural vertebrate population

2021 ◽  
Author(s):  
Sarah F Worsley ◽  
Charli S Davies ◽  
Maria-Elena Mannarelli ◽  
Matthew I Hutchings ◽  
Jan Komdeur ◽  
...  
Keyword(s):  
Natural Population ◽  
Breeding Season ◽  
Body Condition ◽  
Gut Microbiome ◽  
Alpha Diversity ◽  
Host Fitness ◽  
Community Membership ◽  
Long Term Study ◽  
In The Wild ◽  
Individual Body

Abstract Background: The vertebrate gut microbiome (GM) can vary substantially across individuals within the same natural population. Although there is evidence linking the GM to health in captive animals, very little is known about the consequences of GM variation for host fitness in the wild. Here, we explore the relationship between faecal microbiome diversity, body condition and survival using data from the long-term study of a discrete natural population of the Seychelles warbler ( Acrocephalus sechellensis ) on Cousin Island. To our knowledge, this is the first time that GM differences associated with survival have been fully characterised for a natural vertebrate species, across multiple age groups and breeding seasons. Results: We identified substantial variation in GM community structure among sampled individuals, which was partially explained by breeding season (7% of the variance), and host age class (up to 1% of the variance). We also identified significant differences in GM community membership between individuals that survived, versus those that had died by the following breeding season. Individuals that died carried reduced abundances of beneficial taxa in the bacterial order Clostridiales , but increased abundances of taxa that are known to be opportunistic pathogens (e.g. members of the Chloroflexi and Propionibacteriales ). However, there was no association between GM alpha diversity (the diversity of bacterial taxa within a sample) and survival to the next breeding season, or with individual body condition. Additionally, we found no association between GM community membership and individual body condition. Conclusions: These results demonstrate that components of the vertebrate GM can be associated with host fitness in the wild, although whether changes in bacterial abundance contribute to, or are only correlated with, the differential survival observed remains unclear. Importantly, it suggests that components of the GM may be under selection, and, thus, could have the potential to influence the evolution of host species living in natural populations.

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