Claire N. Spottiswoode's research while affiliated with University of Cambridge and other places

Publications (132)

Article
Many mutualisms are exploited by third-party species, which benefit without providing anything in return. Exploitation can either destabilize or promote mutualisms, via mechanisms that are highly dependent on the ecological context. Here we study a remarkable bird-human mutualism, in which wax-eating greater honeyguides (Indicator indicator) guide...
Article
Claire Spottiswoode and colleagues introduce the ancient partnership between wild honeyguides and human honey hunters.
Article
Visual complexity is ubiquitous in nature. Drivers of complexity include selection in coevolutionary arms races between antagonists. However, the causes and consequences of biological complexity and its perception are largely understudied, partly because complexity is difficult to quantify. Here, we address this by studying egg pattern complexity a...
Article
Full-text available
Human–wildlife cooperation occurs when humans and free-living wild animals actively coordinate their behavior to achieve a mutually beneficial outcome. These interactions provide important benefits to both the human and wildlife communities involved, have wider impacts on the local ecosystem, and represent a unique intersection of human and animal...
Article
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Abstract Human‐wildlife cooperation is a type of mutualism in which a human and a wild, free‐living animal actively coordinate their behaviour to achieve a common beneficial outcome. While other cooperative human‐animal interactions involving captive coercion or artificial selection (including domestication) have received extensive attention, we la...
Article
Significance Validating an almost century-old hypothesis, we show that a critical host-specific adaptation in a brood-parasitic bird, mimicry of host egg coloration, is maternally inherited, allowing mothers to transmit specialized mimicry to their daughters irrespective of the father’s host species. This genetic architecture, however, is a double-...
Article
Full-text available
1. Human-wildlife cooperation is a type of mutualism in which a human and a wild, free-living animal actively coordinate their behaviour to achieve a common beneficial outcome. 2. While other cooperative human-animal interactions involving captive coer-cion or artificial selection (including domestication) have received extensive
Article
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The remarkable mutualism between humans and greater honeyguides ( Indicator indicator ) is known still to thrive in only a few places in Africa. Here, we report on the honey-hunting culture of the marginalised Awer people in Kenya, historically a hunter-gatherer culture who today practise a mixed economy including significant amounts of foraging fo...
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Movement of the embryo is essential for musculoskeletal development in vertebrates, yet little is known about whether, and why, species vary. Avian brood parasites exhibit feats of strength in early life as adaptations to exploit the hosts that rear them. We hypothesized that an increase in embryonic movement could allow brood parasites to develop...
Article
High temperatures and low rainfall consistently constrain reproduction in arid-zone bird species. Understanding the mechanisms underlying this pattern is critical for predicting how climate change will influence population persistence and to inform conservation and management. In this study, we analyzed Southern Pied Babbler Turdoides bicolor nestl...
Article
In host–parasite arms races, hosts can evolve signatures of identity to enhance the detection of parasite mimics. In theory, signatures are most effective when within-individual variation is low (‘consistency’), and between-individual variation is high (‘distinctiveness’). However, empirical support for positive covariation in signature consistency...
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High air temperatures have measurable negative impacts on reproduction in wild animal populations, including during incubation in birds. Understanding the mechanisms driving these impacts requires comprehensive knowledge of animal physiology and behaviour under natural conditions. We used a novel combination of a non-invasive doubly labelled water...
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In mimicry systems, receivers discriminate between the stimuli of models and mimics. Weber's Law of proportional processing states that receiver discrimination is based on proportional, not absolute, differences between stimuli. Weber's Law operates in a variety of taxa and modalities, yet it has largely been ignored in the context of mimicry, desp...
Article
Globally, people feed wild animals to interact with nature. Attracting nectarivorous birds to gardens using artificial nectar feeders is increasingly popular, yet little is known about its influence on birds and the plants they pollinate. We investigated effects of nectar feeders on African birds and their plant mutualists, by conducting feeding ex...
Article
Flower colour differs dramatically between populations for some plant species, yet we know little about what drives this variation. Such polymorphisms can be influenced by plant‐pollinator interactions, but whether they are also influenced by pollinator‐mediated plant‐plant interactions is unknown. We test whether flower colour polymorphisms can ar...
Article
Parasite lineages vary widely in species richness. In some clades, speciation is linked to the colonization of new hosts. This is the case in the indigobirds and whydahs (Vidua), brood-parasitic finches whose nestlings mimic the phenotypes of their specific hosts. To understand the factors limiting host colonization and, therefore, speciation, we s...
Preprint
Full-text available
High temperatures and low rainfall consistently constrain reproduction in arid-zone bird species. Understanding the mechanisms underlying this pattern is critical for predicting how climate change will influence population persistence and to inform conservation and management. In this study, we analysed Southern Pied Babbler Turdoides nestling surv...
Article
Full-text available
Climate change is affecting animal populations around the world and one relatively unexplored aspect of species vulnerability is whether and to what extent responses to environmental stressors might be mitigated by variation in group size in social species. We used a 15-year data set for a cooperatively breeding bird, the southern pied babbler Turd...
Preprint
High air temperatures have measurable negative impacts on reproduction in wild animal populations, including during incubation in birds. Understanding the mechanisms driving these impacts requires comprehensive knowledge of animal physiology and behaviour under natural conditions. We used a novel combination of a non-invasive doubly-labelled water...
Cover Page
Full-text available
The grass finches (family Estrildidae) are the host family to the brood-parasitic indigobirds and whydahs (genus Vidua). They are unusual among birds in having highly ornamentedand diverse nestlings. On pages 2526–2538, Jamie et al. provide quantitative evidence that many of these colours and patterns are by nestling Vidua parasites. First and seco...
Article
Some evolutionary radiations produce a number of closely-related species that continue to coexist. In such plant systems, when pre-pollination barriers are weak, relatively strong post-pollination reproductive barriers are required to maintain species boundaries. Even when post-pollination barriers are in place, however, reproductive interference a...
Article
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An improved understanding of life-history responses to current environmental variability is required to predict species-specific responses to anthopogenic climate change. Previous research has suggested that cooperation in social groups may buffer individuals against some of the negative effects of unpredictable climates. We use a 15-year dataset o...
Article
Full-text available
Brood parasites use the parental care of others to raise their young and sometimes employ mimicry to dupe their hosts. The brood‐parasitic finches of the genus Vidua are a textbook example of the role of imprinting in sympatric speciation. Sympatric speciation is thought to occur in Vidua because their mating traits and host preferences are strongl...
Preprint
Full-text available
Increasingly harsh and unpredictable climate regimes are affecting animal populations around the world as climate change advances. One relatively unexplored aspect of species vulnerability to climate change is whether and to what extent responses to environmental stressors might be mitigated by variation in group size in social species. We used a 1...
Preprint
Full-text available
An improved understanding of life history responses to current environmental variability is required to predict species-specific responses to anthopogenic climate change. Previous research has suggested that cooperation in social groups may buffer individuals against some of the negative effects of unpredictable climates. We use a 15-year dataset o...
Article
Full-text available
Variation in weather patterns can influence reproductive effort and success not only within but also between breeding seasons. Where environmental conditions can be highly variable between years, the weather, and particularly extreme weather events such as heat waves and droughts, may exert a strong influence on reproductive effort (number of breed...
Article
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Migration can influence host–parasite dynamics in animals by increasing exposure to parasites, by reducing the energy available for immune defense, or by culling of infected individuals. These mechanisms have been demonstrated in several comparative analyses; however, few studies have investigated whether conspecific variation in migration distance...
Article
Full-text available
Climate models forecast increasing climatic variation and more extreme events, which could increase the variability in animal demographic rates. More variable demographic rates generally lead to lower population growth and can be detrimental to wild populations, especially if the particular demographic rates affected are those to which population g...
Article
Rudd’s Lark Heteromirafra ruddi is a globally threatened species endemic to eastern South Africa’s highland grasslands, where climate envelope modelling has predicted a dramatic reduction in its already small and fragmented distribution. Here we assess recent changes in one of its last strongholds, the Wakkerstroom grasslands. We assessed changes i...
Article
In arms races with parasites, hosts can evolve defences exhibiting extensive variability within populations, which signals individual identity (‘signatures’). However, few such systems have evolved, suggesting that the conditions for their evolution are uncommon. We review (a) polymorphic egg markings that allow hosts of brood-parasitic birds to re...
Article
Full-text available
Brood parasitism has evolved independently in several bird lineages, giving rise to strikingly similar behavioural adaptations that suggest convergent evolution. By comparison, convergence of physiological traits that optimize this breeding strategy has received much less attention, yet these species share many similar physiological traits that opt...
Article
Despite a recent explosion of research on pattern recognition, in both neuroscience and computer vision, we lack a basic understanding of how most animals perceive and respond to patterns in the wild. Avian brood parasites and their hosts provide an ideal study system for investigating the mechanisms of pattern recognition. The cuckoo finch, Anomal...
Article
Full-text available
Obligate brood-parasitic cheats have fascinated natural historians since ancient times. Passing on the costs of parental care to others occurs widely in birds, insects and fish, and often exerts selection pressure on hosts that in turn evolve defences. Brood parasites have therefore provided an illuminating system for researching coevolution. Never...
Article
Depositing faeces at the nest should be expected to carry risks such as increased parasite loads and disease exposure. This perplexing behaviour is unusual in birds but is consistently shown by a handful of species, and has been demonstrated to function in predator deterrence, thermoregulation and prey attraction. Pygmy Falcons Polihierax semitorqu...
Article
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Animal reproductive cycles are commonly triggered by environmental cues of favourable breeding conditions. In arid environments, rainfall may be the most conspicuous cue, but the effects on reproduction of the high inter- and intraannual variation in temperature remain poorly understood, despite being relevant to the current context of global warmi...
Article
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Animal camouflage is a longstanding example of adaptation. Much research has tested how camouflage prevents detection and recognition, largely focusing on changes to an animal’s own appearance over evolution. However, animals could also substantially alter their camouflage by behaviourally choosing appropriate substrates. Recent studies suggest tha...
Article
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When mimicry imposes costs on models, selection may drive the model's phenotype to evolve away from its mimic. For example, brood parasitism often drives hosts to diversify in egg appearance among females within a species, making mimetic parasitic eggs easier to detect. However, when a single parasite species exploits multiple host species, parasit...
Article
When mimicry imposes costs on models, selection may drive the model's phenotype to evolve away from its mimic. For example, brood parasitism often drives hosts to diversify in egg appearance among females within a species, making mimetic parasitic eggs easier to detect. However, when a single parasite species exploits multiple host species, parasit...
Article
Full-text available
There is huge diversity in visual systems and color discrimination abilities, thought to stem from an animal's ecology and life history. Many primate species maintain a polymorphism in color vision, whereby most individuals are dichromats but some females are trichromats, implying that selection sometimes favors dichromatic vision. Detecting camouf...
Article
Full-text available
There is huge diversity in visual systems and color discrimination abilities, thought to stem from an animal’s ecology and life history. Many primate species maintain a polymorphism in color vision, whereby most individuals are dichromats but some females are trichromats, implying that selection sometimes favors dichromatic vision. Detecting camouf...
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Full-text available
\textbf{Background:}$ An understanding of year-round habitat use is essential for determining how carry-over effects shape population dynamics in long-distance migratory songbirds. The recent discovery of long-term migratory staging sites in many species, prior to arrival at final wintering sites, adds complexity to efforts to decipher non-breeding...
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Camouflage is one of the most widespread antipredator defences, and its mechanistic basis has attracted considerable interest in recent years. The effectiveness of camouflage depends on the interaction between an animal's appearance and its background. Concealment can therefore be improved by changes to an animal's own appearance, by behaviorally s...
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The montane forests of northern Mozambique’s isolated massifs are inhabited by numerous range-restricted and threatened bird species, but until recently were extremely little-known. We report on a first avifaunal survey of the isolated montane habitats of Mt Mecula (1 442 m), Niassa National Reserve, notable as the only currently protected montane...
Article
Show me a sign of sweetness to come Communication between humans and domesticated animals is common. Regular communication between humans and wild animals, however, is rare. African honey-guide birds are known to regularly lead human honey-hunters to bee colonies, and the humans, on opening up the nest, leave enough mess for the birds to feast on....
Article
Full-text available
Camouflage is one of the most widespread anti-predator strategies in the animal kingdom, yet no animal can match its background perfectly in a complex environment. Therefore, selection should favour individuals that use information on how effective their camouflage is in their immediate habitat when responding to an approaching threat. In a field s...
Article
As populations shift their ranges in response to global change, local species assemblages can change, setting the stage for new ecological interactions, community equilibria, and evolutionary responses. Here we focus on the range dynamics of four avian brood parasite species and their hosts in southern Africa, in a context of bush encroachment (inc...
Article
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Evading detection by predators is crucial for survival. Camouflage is therefore a widespread adaptation, but despite substantial research effort our understanding of different camouflage strategies has relied predominantly on artificial systems and on experiments disregarding how camouflage is perceived by predators. Here we show for the first time...
Article
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Many long-distance migratory birds sing extensively on their tropical African wintering grounds, but the function of this costly behavior remains unknown. In this study, we carry out a first empirical test of three competing hypotheses, combining a field study of great reed warblers (Acrocephalus arundinaceus) wintering in Africa with a comparative...
Article
Malaria parasites can have strong effects on the population dynamics and evolution of migratory bird species. In many species, parasite transmission occurs on the wintering grounds, but studies to determine the consequences of infection have taken place during the breeding season, when malaria parasites circulate at chronic levels. We examined the...
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The Ethiopian Bush-crow Zavattariornis stresemanni is a charismatic and Endangered endemic bird of southern Ethiopia, whose general biology remains under-studied. We present field notes and observations from 2008 to 2014, covering many aspects of the species’ behaviour and morphology. Bush-crows breed co-operatively in response to both of the local...
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Traits used in communication, such as colour signals, are expected to have positive consequences for reproductive success, but their associations with survival are little understood. Previous studies have mainly investigated linear relationships between signals and survival, but both hump-shaped and U-shaped relationships can also be predicted, dep...
Article
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Dispersal is a critical driver of gene flow, with important consequences for population genetic structure, social interactions and other biological processes. Limited dispersal may result in kin-structured populations in which kin selection may operate, but it may also increase the risk of kin competition and inbreeding. Here, we use a combination...
Article
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Hosts of brood-parasitic birds must distinguish their own eggs from parasitic mimics, or pay the cost of mistakenly raising a foreign chick. Egg discrimination is easier when different host females of the same species each lay visually distinctive eggs (egg 'signatures'), which helps to foil mimicry by parasites. Here, we ask whether brood parasiti...
Article
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Mimicry of a harmless model (aggressive mimicry) is used by egg, chick and fledgling brood parasites that resemble the host's own eggs, chicks and fledglings. However, aggressive mimicry may also evolve in adult brood parasites, to avoid attack from hosts and/or manipulate their perception of parasitism risk. We tested the hypothesis that female cu...
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Full-text available
The Critically Endangered Archer's Lark (now Liben Lark) Heteromirafra archeri was formerly considered to be endemic to north-western Somalia and known only from the Tog Wajaale Plain, where 18 specimens were collected between 1918 and 1922. Fifteen visits between 1970 and 2008 failed to relocate the species there, although populations are now know...
Data
Video S2. Little Bee-eaters not mobbing a Black-collared Barbet dummy.
Data
Video S1. Little Bee-eaters mobbing a Greater Honeyguide dummy.