scispace - formally typeset
Search or ask a question
Journal ArticleDOI

Constraints on egg discrimination and cuckoo-host co-evolution

01 May 1995-Animal Behaviour (Academic Press)-Vol. 49, Iss: 5, pp 1185-1209
TL;DR: It is suggested that host egg variability is a major constraint on the learning mechanism of egg recognition, and justifies a prolonged learning mechanism in which a host can learn to recognize the variation range of its own eggs.
About: This article is published in Animal Behaviour.The article was published on 1995-05-01. It has received 322 citations till now. The article focuses on the topics: Cuckoo & Brood parasite.
Citations
More filters
Journal ArticleDOI
TL;DR: A critical review of the literature is presented which, when combined with the results of some comparative analyses, suggests that just a few selective agents can explain much of the variation in egg appearance.
Abstract: Avian eggs differ so much in their colour and patterning from species to species that any attempt to account for this diversity might initially seem doomed to failure. Here I present a critical review of the literature which, when combined with the results of some comparative analyses, suggests that just a few selective agents can explain much of the variation in egg appearance. Ancestrally, bird eggs were probably white and immaculate. Ancient diversification in nest location, and hence in the clutch's vulnerability to attack by predators, can explain basic differences between bird families in egg appearance. The ancestral white egg has been retained by species whose nests are safe from attack by predators, while those that have moved to a more vulnerable nest site are now more likely to lay brown eggs, covered in speckles, just as Wallace hypothesized more than a century ago. Even blue eggs might be cryptic in a subset of nests built in vegetation. It is possible that some species have subsequently turned these ancient adaptations to new functions, for example to signal female quality, to protect eggs from damaging solar radiation, or to add structural strength to shells when calcium is in short supply. The threat of predation, together with the use of varying nest sites, appears to have increased the diversity of egg colouring seen among species within families, and among clutches within species. Brood parasites and their hosts have probably secondarily influenced the diversity of egg appearance. Each drives the evolution of the other's egg colour and patterning, as hosts attempt to avoid exploitation by rejecting odd-looking eggs from their nests, and parasites attempt to outwit their hosts by laying eggs that will escape detection. This co-evolutionary arms race has increased variation in egg appearance both within and between species, in parasites and in hosts, sometimes resulting in the evolution of egg colour polymorphisms. It has also reduced variation in egg appearance within host clutches, although the benefit thus gained by hosts is not clear.

358 citations


Cites background from "Constraints on egg discrimination a..."

  • ...Thus, mothers and fathers contribute equally to the phenotype of their daughters’ eggs, which suggests that females can have no prior knowledge of the appearance of their eggs, and might explain why this must be learnt (Lotem et al., 1995; Lahti & Lahti, 2001)....

    [...]

Journal ArticleDOI
13 Mar 2003-Nature
TL;DR: It is shown that the breach of host egg defences by cuckoos creates a new stage in the coevolutionary cycle and is suggested that it has selected for the evolution of nestling mimicry in bronze-cuckoos.
Abstract: Cuckoo nestlings that evict all other young from the nest soon after hatching impose a high reproductive cost on their hosts1. In defence, hosts have coevolved strategies to prevent brood parasitism. Puzzlingly, they do not extend beyond the egg stage2,3,4,5. Thus, hosts adept at recognizing foreign eggs remain vulnerable to exploitation by cuckoo nestlings6,7. Here we show that the breach of host egg defences by cuckoos creates a new stage in the coevolutionary cycle. We found that defences used during the egg-laying period by host superb fairy-wrens (Malurus cyaneus) are easily evaded by the Horsfield's bronze-cuckoo (Chrysococcyx basalis), a specialist fairy-wren brood parasite. However, although hosts never deserted their own broods, they later abandoned 40% of nests containing a lone Horsfield's bronze-cuckoo nestling, and 100% of nests with a lone shining bronze-cuckoo nestling (Chrysococcyx lucidus), an occasional fairy-wren brood parasite. Our experiments demonstrate that host discrimination against evictor-cuckoo nestlings is possible, and suggest that it has selected for the evolution of nestling mimicry in bronze-cuckoos.

294 citations

Journal ArticleDOI
TL;DR: It is shown that below a threshold of 19-41% parasitism, the warblers should accept mimetic cuckoo eggs because the costs of rejection outweigh the benefits, whereas above this threshold they should reject.
Abstract: Reed warblers sometimes make recognition errors when faced with a mimetic cuckoo egg in their nest and reject one or more of their own eggs rather than the foreign egg. Using the framework of signal detection theory, we analyse responses to model eggs to quantify the costs and benefits of acceptance versus rejection in parasitized and unparasitized nests. We show that below a threshold of 19-41% parasitism, the warblers should accept mimetic cuckoo eggs because the costs of rejection outweigh the benefits, whereas above this threshold they should reject. The warblers behaved as predicted; when they saw a cuckoo at their nest they usually showed rejection, but without the sight of the cuckoo they behaved appropriately for the average parasitism rate in Britain (6%) and tended to accept.

278 citations

Journal ArticleDOI
TL;DR: These cues correspond exactly to the principal differences between host and parasitic eggs, showing that hosts use the most reliable available cues in making rejection decisions, and select for parasitic eggs that are increasingly mimetic in a range of visual attributes.
Abstract: One of the most striking outcomes of coevolution between species is egg mimicry by brood parasitic birds, resulting from rejection behavior by discriminating host parents. Yet, how exactly does a host detect a parasitic egg? Brood parasitism and egg rejection behavior provide a model system for exploring the relative importance of different visual cues used in a behavioral task. Although hosts are discriminating, we do not know exactly what cues they use, and to answer this it is crucial to account for the receiver's visual perception. Color, luminance (“perceived lightness”) and pattern information have never been simultaneously quantified and experimentally tested through a bird's eye. The cuckoo finch Anomalospiza imberbis and its hosts show spectacular polymorphisms in egg appearance, providing a good opportunity for investigating visual discrimination owing to the large range of patterns and colors involved. Here we combine field experiments in Africa with modeling of avian color vision and pattern discrimination to identify the specific visual cues used by hosts in making rejection decisions. We found that disparity between host and foreign eggs in both color and several aspects of pattern (dispersion, principal marking size, and variability in marking size) were important predictors of rejection, especially color. These cues correspond exactly to the principal differences between host and parasitic eggs, showing that hosts use the most reliable available cues in making rejection decisions, and select for parasitic eggs that are increasingly mimetic in a range of visual attributes.

258 citations


Cites background from "Constraints on egg discrimination a..."

  • ...Responses of common cuckoo hosts to foreign eggs are highly sensitive to perceived risk of parasitism, including risk perception socially transmitted from conspecifics (26, 27)....

    [...]

  • ...Learning also plays a powerful role in antiparasite defenses, including individual learningof ownegg appearance (26)....

    [...]

Journal ArticleDOI
21 Aug 2003-Nature
TL;DR: It is shown that all indigobird species are similar genetically, but are significantly differentiated in both mitochondrial haplotype and nuclear allele frequencies, which support a model of recent sympatric speciation.
Abstract: A growing body of empirical and theoretical work supports the plausibility of sympatric speciation1,2,3, but there remain few examples in which all the essential components of the process are well understood. The African indigobirds Vidua spp. are host-specific brood parasites. Indigobird nestlings are reared along with host young, and mimic the mouth markings of their respective hosts4,5,6. As adults, male indigobirds mimic host song4,5,6,7, whereas females use these songs to choose both their mates and the nests they parasitize8. These behavioural mechanisms promote the cohesion of indigobird populations associated with a given host species, and provide a mechanism for reproductive isolation after a new host is colonized. Here we show that all indigobird species are similar genetically, but are significantly differentiated in both mitochondrial haplotype and nuclear allele frequencies. These data support a model of recent sympatric speciation. In contrast to the cuckoo Cuculus canorus, in which only female lineages are faithful to specific hosts9,10, host switches have led to speciation in indigobirds because both males and females imprint on their hosts8,11.

234 citations


Cites background from "Constraints on egg discrimination a..."

  • ...A potential solution is that host discrimination varies with ambient food supply and/or the previous experience of individual host...

    [...]

References
More filters
Journal ArticleDOI
TL;DR: The arms race concept is suggested to help to resolve three long-standing questions in evolutionary theory: one lineage may drive the other to extinction, one may reach an optimum, thereby preventing the other from doing so, and both sides may reach a mutual local optimum.
Abstract: An adaptation in one lineage (e.g. predators) may change the selection pressure on another lineage (e.g. prey), giving rise to a counter-adaptation. If this occurs reciprocally, an unstable runaway escalation or 9arms race9 may result. We discuss various factors which might give one side an advantage in an arms race. For example, a lineage under strong selection may out-evolve a weakly selected one (9the life-dinner principle9). We then classify arms races in two independent ways. They may be symmetric or asymmetric, and they may be interspecific or intraspecific. Our example of an asymmetric interspecific arms race is that between brood parasites and their hosts. The arms race concept may help to reduce the mystery of why cuckoo hosts are so good at detecting cuckoo eggs, but so bad at detecting cuckoo nestlings. The evolutionary contest between queen and worker ants over relative parental investment is a good example of an intraspecific asymmetric arms race. Such cases raise special problems because the participants share the same gene pool. Interspecific symmetric arms races are unlikely to be important, because competitors tend to diverge rather than escalate competitive adaptations. Intraspecific symmetric arms races, exemplified by adaptations for male-male competition, may underlie Cope9s Rule and even the extinction of lineages. Finally we consider ways in which arms races can end. One lineage may drive the other to extinction; one may reach an optimum, thereby preventing the other from doing so; a particularly interesting possibility, exemplified by flower-bee coevolution, is that both sides may reach a mutual local optimum; lastly, arms races may have no stable end but may cycle continuously. We do not wish necessarily to suggest that all, or even most, evolutionary change results from arms races, but we do suggest that the arms race concept may help to resolve three long-standing questions in evolutionary theory. 9Wonderful and admirable as most instincts are, yet they cannot be considered as absolutely perfect: there is a constant struggle going on throughout nature between the instinct of the one to escape its enemy and of the other to secure its prey9 (Charles Darwin, in Romanes I883).

1,931 citations


"Constraints on egg discrimination a..." refers background in this paper

  • ...According to the ‘arms race’ hypothesis, the acceptance of parasitic eggs or nestlings is a maladaptive result of an evolutionary lag in the development of counter-adaptations by the host (Rothstein 1975a, 1982a; Dawkins & Krebs 1979; Davies & de L. Brooke 1988, 1989b; Moksnes et al. 1990)....

    [...]

  • ...The co-existence of rejection and acceptance of cuckoo eggs within a host population has been commonly explained by the arms race model (Dawkins & Krebs 1979; Kelly 1987; Davies & de L. Brooke 1989b; Moksnes et al. 1990)....

    [...]

Book
01 Jan 1964

689 citations


"Constraints on egg discrimination a..." refers background in this paper

  • ...The production of egg pigmentation may decrease in old age (Solomon 1991) and under stress (Welty 1975; Solomon 1991)....

    [...]

Journal ArticleDOI
TL;DR: Systems in which the interacting species are few (optimally only two) provide the clearest examples of coevolution, which includes many mutualistic relationships and some parasite-host associations.
Abstract: Many putative examples of coevolution do not stand up to critical analysis. A rigorous definition of coevolution requires that a trait in one species has evolved in response to a trait of another species, which trait was itself evolved in response to the first species (50, 69). This type of intimate, reciprocal evolutionary relationship is hard to demonstrate because most species interact with many other species, all of which may affect their evolution. For example, a host species is likely to be affected by many types of parasitic helminths and protozoans. Accordingly, some of its defenses will be fairly general and not attributable to any particular species of parasite. Such situations are termed diffuse coevolution, as opposed to pairwise coevolution in which adaptations have a stepwise, reciprocal nature. Unfortunately, diffuse coevolution is difficult to document because additional species may need to be considered. Also, adapting to many species may compromise adaptations to any one species so much that coevolutionary traits are weakly expressed and hard to identify. Systems in which the interacting species are few (optimally only two) provide the clearest examples of coevolution. Such systems include many mutualistic relationships and some parasite-host associations (51). Among the latter, brood parasitism provides some of the most persuasive examples of coevolution because it often involves small numbers of species.

675 citations


"Constraints on egg discrimination a..." refers background or result in this paper

  • ...Even at evolutionary equilibrium, cuckoo egg mimicry may still not be perfect if the range of variation of egg types in the host population is much larger than that of a particular female (Rothstein 1990)....

    [...]

  • ...Among cuckoo hosts in Europe and Britain, local parasitism rates can be as high as 20% (Wyllie 1981; Cramp 1985; Davies & de L. Brooke 1988; Rothstein 1990), while the overall parasitism rate for a given species, as shown by the British nest record system, is only 1–6% (Davies & de L....

    [...]

  • ...The alternative hypothesis of evolutionary equilibrium was previously considered but rejected in the absence of supporting evidence (Davies & de L. Brooke 1988, 1989b; Rothstein 1990; but see Moksnes et al. 1993)....

    [...]

  • ...Numerous experimental studies have recently shown the existence of co-evolved adaptations in parasitic birds and their hosts, and have demonstrated the usefulness of brood parasitism as a model system for the study of co-evolution (reviewed by Rothstein 1990)....

    [...]

  • ...Among cuckoo hosts in Europe and Britain, local parasitism rates can be as high as 20% (Wyllie 1981; Cramp 1985; Davies & de L. Brooke 1988; Rothstein 1990), while the overall parasitism rate for a given species, as shown by the British nest record system, is only 1–6% (Davies & de L. Brooke 1989b)....

    [...]

01 Jan 1990
TL;DR: A rigorous definition of coevolution requires that a trait in one species has evolved in response to a trait of another species, which trait was itself evolved by the first species as discussed by the authors.
Abstract: Many putative examples of coevolution do not stand up to critical analysis. A rigorous definition of coevolution requires that a trait in one species has evolved in response to a trait of another species, which trait was itself evolved in response to the first species (50, 69). This type of intimate, reciprocal evolutionary relationship is hard to demonstrate because most species interact with many other species, all of which may affect their evolution. For example, a host species is likely to be affected by many types of parasitic helminths and protozoans. Accordingly, some of its defenses will be fairly general and not attributable to any particular species of parasite. Such situations are termed diffuse coevolution, as opposed to pairwise coevolution in which adaptations have a stepwise, reciprocal nature. Unfortunately, diffuse coevolution is difficult to document because additional species may need to be considered. Also, adapting to many species may compromise adaptations to any one species so much that coevolutionary traits are weakly expressed and hard to identify. Systems in which the interacting species are few (optimally only two) provide the clearest examples of coevolution. Such systems include many mutualistic relationships and some parasite-host associations (51). Among the latter, brood parasitism provides some of the most persuasive examples of coevolution because it often involves small numbers of species.

656 citations

Journal ArticleDOI
TL;DR: Reed warblers did not discriminate against unlike chicks (another species) and did not favour either a cuckoo chick or their own chicks when these were placed in two nests side by side and experiments showed that host discrimination selects for egg mimicry by cuckoos.

637 citations