scholarly journals The Perceptual and Cognitive Processes That Govern Egg Rejection in Hosts of Avian Brood Parasites

2021 ◽  
Vol 9 ◽  
Author(s):  
Daniel Hanley ◽  
Samantha L. Rutledge ◽  
Juliana Villa
Keyword(s):  
Cognitive Processing ◽  
Cognitive Processes ◽  
Selective Pressure ◽  
Null Model ◽  
Egg Rejection ◽  
Egg Recognition ◽  
Brood Parasites ◽  
The Past ◽  
The Cost ◽  
Receptor Noise

Hosts of avian brood parasites are under intense selective pressure to prevent or reduce the cost of parasitism. Many have evolved refined egg discrimination abilities, which can select for eggshell mimicry in their parasite. A classic assumption underlying these coevolutionary dynamics is that host egg recognition depends on the perceivable difference between their own eggs and those of their parasite. Over the past two decades, the receptor noise-limited (RNL) model has contributed to our understanding of these coevolutionary interactions by providing researchers a method to predict a host’s ability to discriminate a parasite’s egg from its own. Recent research has shown that some hosts are more likely to reject brown eggs than blue eggs, regardless of the perceived differences to their own. Such responses suggest that host egg recognition may be due to perceptual or cognitive processes not currently predictable by the RNL model. In this perspective, we discuss the potential value of using the RNL model as a null model to explore alternative perceptual processes and higher-order cognitive processes that could explain how and why some hosts make seemingly counter-intuitive decisions. Further, we outline experiments that should be fruitful for determining the perceptual and cognitive processing used by hosts for egg recognition tasks.

scholarly journals Cognition and the evolution of camouflage

2016 ◽  
Vol 283 (1825) ◽  
pp. 20152890 ◽  
Author(s):  
John Skelhorn ◽  
Candy Rowe
Keyword(s):  
Cognitive Processes ◽  
Selective Pressure ◽  
Animal Cognition ◽  
Future Research ◽  
Ecological Context ◽  
The Past ◽  
Camouflage Patterns ◽  
Predator Defence

Camouflage is one of the most widespread forms of anti-predator defence and prevents prey individuals from being detected or correctly recognized by would-be predators. Over the past decade, there has been a resurgence of interest in both the evolution of prey camouflage patterns, and in understanding animal cognition in a more ecological context. However, these fields rarely collide, and the role of cognition in the evolution of camouflage is poorly understood. Here, we review what we currently know about the role of both predator and prey cognition in the evolution of prey camouflage, outline why cognition may be an important selective pressure driving the evolution of camouflage and consider how studying the cognitive processes of animals may prove to be a useful tool to study the evolution of camouflage, and vice versa. In doing so, we highlight that we still have a lot to learn about the role of cognition in the evolution of camouflage and identify a number of avenues for future research.

scholarly journals Visual acuity and egg spatial chromatic contrast predict egg rejection behavior of American robins

2020 ◽  
Vol 223 (20) ◽  
pp. jeb229609
Author(s):  
Alec B. Luro ◽  
Esteban Fernández-Juricic ◽  
Patrice Baumhardt ◽  
Mark E. Hauber
Keyword(s):  
Visual Acuity ◽  
Host Species ◽  
Spatial Vision ◽  
Viewing Distance ◽  
Egg Rejection ◽  
Chromatic Contrast ◽  
Brood Parasites ◽  
American Robins ◽  
Avian Visual System ◽  
The Cost

ABSTRACTColor and spatial vision is critical for recognition and discrimination tasks affecting fitness, including finding food and mates, and recognizing offspring. For example, as a counter defense to avoid the cost of raising the unrelated offspring of obligate interspecific avian brood parasites, many host species routinely view, recognize and remove the foreign egg(s) from their nests. Recent research has shown that host species visually attend to both chromatic and spatial pattern features of eggs; yet how hosts simultaneously integrate these features together when recognizing eggs remains an open question. Here, we tested egg rejection responses of American robins (Turdus migratorius) using a range of 3D-printed model eggs covered with blue and yellow checkered patterns differing in relative square sizes. We predicted that robins would reject a model egg if they could visually resolve the blue and yellow squares as separate features, or accept it if the squares blended together and appeared similar in color to the natural blue–green color of robin eggs as perceived by the avian visual system. As predicted, the probability of robins rejecting a model egg increased with greater sizes of its blue and yellow squares. Our results suggest that chromatic visual acuity and viewing distance have the potential to limit the ability of a bird to recognize a foreign egg in its nest, thus providing a limitation to host egg recognition that obligate interspecific avian brood parasites may exploit.

scholarly journals Visual acuity and egg spatial chromatic contrast predict egg rejection behavior of American robins

2020 ◽  
Author(s):  
Alec B. Luro ◽  
Esteban Fernández-Juricic ◽  
Patrice Baumhardt ◽  
Mark E. Hauber
Keyword(s):  
Visual Acuity ◽  
Host Species ◽  
Spatial Vision ◽  
Viewing Distance ◽  
Egg Rejection ◽  
Chromatic Contrast ◽  
Brood Parasites ◽  
American Robins ◽  
Avian Visual System ◽  
The Cost

AbstractColor and spatial vision are critical for recognition and discrimination tasks affecting fitness, including finding food and mates and recognizing offspring. For example, as a counter defense to avoid the cost of raising the unrelated offspring of obligate interspecific avian brood parasites, many host species routinely view, recognize, and remove the foreign egg(s) from their nests. Recent research has shown that host species visually attend to both chromatic and spatial pattern features of eggs; yet how hosts simultaneously integrate these features together when recognizing eggs remains an open question. Here, we tested egg rejection responses of American robins (Turdus migratorius) using a range of 3D-printed model eggs covered with blue and yellow checkered patterns differing in relative square sizes. We predicted that robins would reject a model egg if they could visually resolve the blue and yellow squares as separate features or accept it if the squares blended together and appeared similar in color to the natural blue-green color of robin eggs as perceived by the avian visual system. As predicted, the probability of robins rejecting a model egg increased with greater sizes of its blue and yellow squares. Our results suggest that chromatic visual acuity and viewing distance have the potential to limit the ability of a bird to recognize a foreign egg in its nest, thus providing a limitation to host egg recognition that obligate interspecific avian brood parasites may exploit.

scholarly journals Absence of anti-parasitic defenses in an Asian population of the magpie, a regular host of the great spotted cuckoo in Europe

2020 ◽  
Author(s):  
Canchao Yang ◽  
Jialiang Huang ◽  
Wei Liang ◽  
Anders P Møller
Keyword(s):  
Asian Population ◽  
Egg Rejection ◽  
Brood Parasite ◽  
Pica Pica ◽  
Host Nest ◽  
Clamator Glandarius ◽  
Brood Parasites ◽  
Antagonistic Coevolution ◽  
The Past ◽  
Different Populations

Abstract Antagonistic coevolution such as that between obligate brood parasites and their hosts promotes the evolution of a variety of trickeries that enhance successful rearing of their offspring. They do that by using host parental care to enhance their reproductive success, which in turn selects for host nest defenses or egg rejection. Studying these adaptations and counter-adaptations in different populations helps us to understand the complexity of coevolution between hosts and parasites. Here, we tested for anti-parasite defenses in an Asian population of magpies Pica pica, which is used as a regular host by the great spotted cuckoo Clamator glandarius in Europe. Unlike most magpie populations in Europe, cuckoo parasitism and specific anti-parasite defenses are absent from this Asian population. None of the cuckoos in the Asian population of magpies were capable of exploiting the magpies. That was due to magpies being evictors smaller than cuckoos that could not successfully utilize brood reducing hosts. Thus, the absence of cuckoo parasitism may be due to the absence of non-evictor brood parasites, while the absence of defenses is likely to be explained by the absence of coevolutionary interaction with any brood parasite in both the present and the past.

scholarly journals Egg retrieval versus egg rejection in cuckoo hosts

2019 ◽  
Vol 374 (1769) ◽  
pp. 20180200 ◽  
Author(s):  
Canchao Yang ◽  
Wei Liang ◽  
Anders P. Møller
Keyword(s):  
Brood Parasitism ◽  
Visual Cues ◽  
Egg Rejection ◽  
Egg Recognition ◽  
Theme Issue ◽  
Brood Parasites ◽  
Cavity Nesting ◽  
Series Of Experiments ◽  
Avian Brood Parasitism ◽  
Different Levels

Before complex nests evolved, birds laid eggs on the ground, and egg retrieval evolved as an adaptation against accidental displacement of eggs outside the nest. Therefore, egg retrieval is an ancient, and likely ancestral, widespread behaviour in birds. However, it has received little attention in studies of avian brood parasitism, perhaps because most parasitism occurs in species with complex nests, a context in which egg retrieval seems irrelevant. However, for cavity-nesting hosts of avian brood parasites, egg retrieval may still play an important role in the coevolutionary interactions between obligate brood parasites and hosts, because egg retrieval can be considered to be antagonistic to egg rejection behaviour in hosts, yet both may involve cognition to recognize eggs. We hypothesized that (1) cavity-nesting hosts should retrieve misplaced eggs from outside the nest cup, (2) brood parasitism has modulated egg retrieval behaviour in cavity-nesting hosts and (3) hosts use the same visual cues for decision-making during egg recognition in both egg retrieval and egg rejection actions. To test these hypotheses, we performed a series of experiments in a cavity-nesting host, the green-backed tit (Parus monticolus). Foreign eggs with different levels of mimicry were placed within or outside nest cups of hosts to test their responses. We found that host decisions about whether to retrieve or reject an egg both depended on the degree of mimicry. However, hosts sometimes first retrieved poorly mimetic foreign eggs and then rejected them. Alternatively, hosts sometimes failed to retrieve highly mimetic conspecific eggs. We suggest that egg retrieval in hosts is likely to be a result of the interaction between ancient retrieval behaviour and subsequent adaptation against brood parasitism.This article is part of the theme issue ‘The coevolutionary biology of brood parasitism: from mechanism to pattern’.

scholarly journals The limits of egg recognition: testing acceptance thresholds of American robins in response to decreasingly egg-shaped objects in the nest

2021 ◽  
Vol 8 (1) ◽  
pp. 201615
Author(s):  
Mark E. Hauber ◽  
Sarah K. Winnicki ◽  
Jeffrey P. Hoover ◽  
Daniel Hanley ◽  
Ian R. Hays
Keyword(s):  
A Priori ◽  
Three Dimensional ◽  
Continuous Variation ◽  
Egg Rejection ◽  
Egg Recognition ◽  
Shape Variation ◽  
Brood Parasites ◽  
Evolutionary Origins ◽  
American Robins ◽  
Fallen Leaves

Some hosts of avian brood parasites reduce or eliminate the costs of parasitism by removing foreign eggs from the nest (rejecter hosts). In turn, even acceptor hosts typically remove most non-egg-shaped objects from the nest, including broken shells, fallen leaves and other detritus. In search for the evolutionary origins and sensory mechanisms of egg rejection, we assessed where the potential threshold between egg recognition and nest hygiene may lie when it comes to stimulus shape. Most previous studies applied comparisons of egg-sized objects with non-continuous variation in shape. Here, instead, we used two series of three-dimensional-printed objects, designed a priori to increasingly diverge from natural eggs along two axes (width or angularity) of shape variation. As predicted, we detected transitions from mostly acceptance to mostly rejection in the nests of American robins Turdus migratorius along each of the two axes. Our methods parallel previous innovations in egg-rejection studies through the use of continuous variation in egg coloration and maculation contrast, to better understand the sensory limits and thresholds of variation in egg recognition and rejection in diverse hosts of avian brood parasites.

scholarly journals Egg discrimination along a gradient of natural variation in eggshell coloration

2017 ◽  
Vol 284 (1848) ◽  
pp. 20162592 ◽  
Author(s):  
Daniel Hanley ◽  
Tomáš Grim ◽  
Branislav Igic ◽  
Peter Samaš ◽  
Analía V. López ◽  
...  
Keyword(s):  
Cognitive Processes ◽  
Natural Variation ◽  
Decision Rules ◽  
Egg Recognition ◽  
Adaptive Responses ◽  
Brood Parasites ◽  
Sensory Reception ◽  
Egg Colour ◽  
Eggshell Colour ◽  
Colour Gradient

Accurate recognition of salient cues is critical for adaptive responses, but the underlying sensory and cognitive processes are often poorly understood. For example, hosts of avian brood parasites have long been assumed to reject foreign eggs from their nests based on the total degree of dissimilarity in colour to their own eggs, regardless of the foreign eggs' colours. We tested hosts' responses to gradients of natural (blue-green to brown) and artificial (green to purple) egg colours, and demonstrate that hosts base rejection decisions on both the direction and degree of colour dissimilarity along the natural, but not artificial, gradient of egg colours. Hosts rejected brown eggs and accepted blue-green eggs along the natural egg colour gradient, irrespective of the total perceived dissimilarity from their own egg's colour. By contrast, their responses did not vary along the artificial colour gradient. Our results demonstrate that egg recognition is specifically tuned to the natural gradient of avian eggshell colour and suggest a novel decision rule. These results highlight the importance of considering sensory reception and decision rules when studying perception, and illustrate that our understanding of recognition processes benefits from examining natural variation in phenotypes.

Measuring the cost of environmental compliance for Waikato dairy farmers - a survey approach

2015 ◽  
Vol 77 ◽  
pp. 159-166
Author(s):  
T.O.R. Macdonald ◽  
J.S. Rowarth ◽  
F.G. Scrimgeour
Keyword(s):  
Qualitative Data ◽  
Management Practice ◽  
Dairy Farm ◽  
Environmental Compliance ◽  
Dairy Farmers ◽  
The Past ◽  
Farm Systems ◽  
The Cost ◽  
Farm System ◽  
Survey Approach

The link between dairy farm systems and cost of environmental compliance is not always clear. A survey of Waikato dairy farmers was conducted to establish the real (non-modelled) cost of compliance with environmental regulation in the region. Quantitative and qualitative data were gathered to improve understanding of compliance costs and implementation issues for a range of Waikato farm systems. The average oneoff capital cost of compliance determined through a survey approach was $1.02 per kg milksolids, $1490 per hectare and $403 per cow. Costs experienced by Waikato farmers have exceeded average economic farm surplus for the region in the past 5 years. As regulation increases there are efficiencies to be gained through implementing farm infrastructure and farm management practice to best match farm system intensity. Keywords: Dairy, compliance, farm systems, nitrogen, Waikato

Attraction of prey

2018 ◽  
Author(s):  
John D. Horner ◽  
Bartosz J. Płachno ◽  
Ulrike Bauer ◽  
Bruno Di Giusto
Keyword(s):  
Visual Cues ◽  
Synergistic Action ◽  
Carnivorous Plants ◽  
Future Research ◽  
Acoustic Cues ◽  
Qualitative And Quantitative Analysis ◽  
Qualitative And Quantitative ◽  
The Past ◽  
The Cost ◽  
Prey Attraction

The ability to attract prey has long been considered a universal trait of carnivorous plants. We review studies from the past 25 years that have investigated the mechanisms by which carnivorous plants attract prey to their traps. Potential attractants include nectar, visual, olfactory, and acoustic cues. Each of these has been well documented to be effective in various species, but prey attraction is not ubiquitous among carnivorous plants. Directions for future research, especially in native habitats in the field, include: the qualitative and quantitative analysis of visual cues, volatiles, and nectar; temporal changes in attractants; synergistic action of combinations of attractants; the cost of attractants; and responses to putative attractants in electroantennograms and insect behavioral tests.

Effect of Sleep Loss on Pain

2020 ◽  
pp. 556-608
Author(s):  
Chloe Alexandre ◽  
Alban Latremoliere ◽  
Patrick H. Finan
Keyword(s):  
Cognitive Processing ◽  
Sleep Disturbances ◽  
Inhibitory Pathways ◽  
Inflammatory Processes ◽  
Lack Of Sleep ◽  
Significant Extension ◽  
Neurological Processes ◽  
Dynamic Components ◽  
The Cost ◽  
System Metabolism

With the advent of modern lifestyles, there has been a significant extension of daily activities, mostly at the cost of sleep. Lack of sleep affects many biological systems, including various cognitive functions, the immune system, metabolism, and pain. Both sleep and pain are complex neurological processes that encompass many dynamic components. As a result, defining the precise interactions between these two systems represents a challenge, especially for chronic paradigms. This chapter describes how sleep is measured and how it can be experimentally altered in humans and animal models, and, in turn, how sleep disturbances, either acute or chronic, can affect different aspects of pain. Possible mechanisms involved are discussed, including an increase in inflammatory processes, a loss of nociceptive inhibitory pathways, and a defect in the cognitive processing of noxious inputs.

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