The function of episodic memory in animals.

The best-known example of episodic memory in animals came from food-storing birds. One of the beauties of the food-storing system was that inherent in the behaviour were the elements that (at the time) made up episodic memory: what, where and when. While there were then already plenty of data on animals' ability to put together what and where, the addition of the time element in animals' memory and its testing was one that was both new and experimentally challenging.

Architectural traditions in the structures built by cooperative weaver birds.

Humans cooperate to build complex structures with culture-specific architectural styles. However, they are not the only animals to build complex structures nor to have culture. We show that social groups of white-browed sparrow weavers () build structures (nests for breeding and multiple single-occupant roosts for sleeping) that differ architecturally among groups.

Anthropogenic nest material use in a global sample of birds.

As humans increasingly modify the natural world, many animals have responded by changing their behaviour. Understanding and predicting the extent of these responses is a key step in conserving these species. For example, the tendency for some species of birds to incorporate anthropogenic items-particularly plastic material-into their nests is of increasing concern, as in some cases, this behaviour has harmful effects on adults, young and eggs.

Nest architecture influences host use by avian brood parasites and is shaped by coevolutionary dynamics.

Brood (social) parasites and their hosts exhibit a wide range of adaptations and counter-adaptations as part of their ongoing coevolutionary arms races. Obligate avian brood parasites are expected to use potential host species with more easily accessible nests, while potential hosts are expected to evade parasitism by building more concealed nests that are difficult for parasites to enter and in which to lay eggs. We used phylogenetically informed comparative analyses, a global database of the world's brood parasites, their host species, and the design of avian host and non-host nests (approx.

Beak shape and nest material use in birds.

The evolution of behaviour can both influence, and be influenced by, morphology. Recent advances in methods and data availability have facilitated broad-scale investigations of physical form and behavioural function in many contexts, but the relationship between animal morphology and object manipulation-particularly objects used in construction-remains largely unknown. Here, we employ a new global database of nest materials used by 5924 species of birds together with phylogenetically informed random forest models to evaluate the link between beak shape and these nest-building materials.

Bird nest building: visions for the future.

Successful reproduction for most birds requires them to have built 'good' nests. The remarkable diversity of nests across approximately 10 000 species of living birds suggests that 'good' nest design depends critically on a species' microhabitat, life history and behaviour. Unravelling the key drivers of nest diversity remains a key research priority-bolstered by renewed appreciation for nest museum collections and increasing correlational field and experimental laboratory data.

Adding the neuro to cognition: from food storing to nest building.

Typically, investigations of animal cognition couple careful experimental manipulations with examination of the animal's behavioural responses. Sometimes those questions have included attempts to describe the neural underpinnings of the behavioural outputs. Over the past 25 years, behaviours that involve spatial learning and memory (such as navigation and food storing) has been one context in which such dual or correlated investigations have been both accessible and productive.

Nests and nest building in birds.

Bird nests have long attracted human interest, both as beautiful creations and as important constructions. They are important constructions because avian parents use them to protect their developing eggs and young from the dangers presented by the elements and predators. Despite sharing these protective functions, however, bird nests can be remarkably structurally variable, being built from a wide diversity of materials, and placed in all manner of locations.

Global drivers of variation in cup nest size in passerine birds.

The size of a bird's nest can play a key role in ensuring reproductive success and is determined by a variety of factors. The primary function of the nest is to protect offspring from the environment and predators. Field studies in a number of passerine species have indicated that higher-latitude populations in colder habitats build larger nests with thicker walls compared to lower-latitude populations, but that these larger nests are more vulnerable to predation.

Size is relative: use of relational concepts by wild hummingbirds.

Rufous hummingbirds () will readily learn the location and the colour of rewarded flowers within their territory. But if these birds could apply a relational concept such as 'the larger flowers have more nectar', they could forego learning the locations of hundreds of individual flowers. Here, we investigated whether wild male territorial rufous hummingbirds might use 'larger than' and 'smaller than' relational rules and apply them to flowers of different sizes.

It Began in Ponds and Rivers: Charting the Beginnings of the Ecology of Fish Cognition.

But fish cognitive ecology did not begin in rivers and streams. Rather, one of the starting points for work on fish cognitive ecology was work done on the use of visual cues by homing pigeons. Prior to working with fish, Victoria Braithwaite helped to establish that homing pigeons rely not just on magnetic and olfactory cues but also on visual cues for successful return to their home loft.

Involvement of the neural social behaviour network during social information acquisition in zebra finches (Taeniopygia guttata).

Female zebra finches Taeniopygia guttata will copy the novel foraging choice of males. The degree to which they do so, however, can vary considerably. Among-individual differences in social learning and their underlying neural pathways have received relatively little attention and remain poorly understood.

Reproductive consequences of material use in avian nest construction.

Birds' nests represent a rich behavioural 'fingerprint', comprising several important decisions-not the least of which is the selection of appropriate material. Material selection in nest-building birds is thought to reflect, in part, builder-birds' use of the 'best' material-in terms of physical properties (e.g.

Hummingbirds modify their routes to avoid a poor location.

Traplining, when animals repeat the order in which they visit a number of locations, is taxonomically widespread, but little is known about which factors influence the routes that animals follow. For example, as the quality of rewarding locations changes over time, foragers are expected to update their traplines, either to prioritize locations where the reward increases or to avoid locations that have ceased to be profitable. Here, we tested how traplining wild hummingbirds responded to increases or to decreases in the sucrose concentration of one of the flowers on their trapline.

Not by transmission alone: the role of invention in cultural evolution.

Innovation-the combination of invention and social learning-can empower species to invade new niches via cultural adaptation. Social learning has typically been regarded as the fundamental driver for the emergence of traditions and thus culture. Consequently, invention has been relatively understudied outside the human lineage-despite being the source of new traditions.

Object manipulation without hands.

Our current understanding of manipulation is based on primate hands, resulting in a detailed but narrow perspective of ways to handle objects. Although most other animals lack hands, they are still capable of flexible manipulation of diverse objects, including food and nest materials, and depend on dexterity in object handling to survive and reproduce. Birds, for instance, use their bills and feet to forage and build nests, while insects carry food and construct nests with their mandibles and legs.

The Impact of Acute Loud Noise on the Behavior of Laboratory Birds.

Husbandry procedures and facility settings, such as low-frequency fire alarms, can produce noises in a laboratory environment that cause stress to animals used in research. However, most of the data demonstrating harmful effects that have, consequently, led to adaptations to management, have largely come from laboratory rodents with little known of the impacts on avian behavior and physiology. Here we examined whether exposure to a routine laboratory noise, a low-frequency fire alarm test, induced behavioral changes in laboratory zebra finches ().

Estimating on the fly: The approximate number system in rufous hummingbirds (Selasphorus rufus).

When presented with resources that differ in quantity, many animals use a numerosity system to discriminate between them. One taxonomically widespread system is the approximate number system. This is a numerosity system that allows the rapid evaluation of the number of objects in a group and which is regulated by Weber's Law.

The rationality of decisions depends on behavioural context.

Decision makers can be described as economically rational (making consistent choices), or economically irrational (making choices that vary with the options available). As the extent to which animals can and do make rational versus irrational decisions remains unclear, we tested the decision-making strategies of female Nasonia vitripennis parasitic wasps in two behavioural contexts: oviposition and foraging. In our first experiment, to determine whether oviposition preferences changed depending on the options available, we presented females with a high and a medium-quality blow fly host to parasitize, and gave some females an additional low or very low quality 'decoy' host.

Neural Circuits Underlying Nest Building in Male Zebra Finches.

Nest building consists of a series of motor actions, which are concomitant with activity in regions of the anterior motor pathway, the social behavior network, and the reward circuity in nest building adult male zebra finches (Taeniopygia guttata). It is not clear, however, whether this activity is due to nest building, collection, and/or manipulation of nest material. To identify which areas of the brain are specifically involved, we used immunohistochemistry to quantify the immediate early gene c-Fos in male zebra finches that were nest building (Building), birds given a nest box but could interact only with tied down nest material (Fixed), and birds that were not given a nest box or nest material (Control).

Numerical ordinality in a wild nectarivore.

Ordinality is a numerical property that nectarivores may use to remember the specific order in which to visit a sequence of flowers, a foraging strategy also known as traplining. In this experiment, we tested whether wild, free-living rufous hummingbirds () could use ordinality to visit a rewarded flower. Birds were presented with a series of linear arrays of 10 artificial flowers; only one flower in each array was rewarded with sucrose solution.

Ecology and allometry predict the evolution of avian developmental durations.

The duration of the developmental period represents a fundamental axis of life-history variation, yet broad insights regarding the drivers of this diversity are currently lacking. Here, we test mechanistic and ecological explanations for the evolution of developmental duration using embryological data and information on incubation and fledging for 3096 avian species. Developmental phases associated primarily with growth are the longest and most variable, consistent with a role for allometric constraint in determining the duration of development.

Early-life adversity programs long-term cytokine and microglia expression within the HPA axis in female Japanese quail.

Stress exposure during prenatal and postnatal development can have persistent and often dysfunctional effects on several physiological systems, including immune function, affecting the ability to combat infection. The neuroimmune response is inextricably linked to the action of the hypothalamic-pituitary-adrenal (HPA) axis. Cytokines released from neuroimmune cells, including microglia, activate the HPA axis, while glucocorticoids in turn regulate cytokine release from microglia.

Social learning about construction behaviour via an artefact.

One source of public information may be the enduring products of others' behaviour, such as discarded tools or vacated nests. Here, we examined whether observation of a nest affects the material captive zebra finch males prefer when they construct their first nest. It does: for first-time nest construction, males that viewed only an empty cage preferred the colour of material each initially favoured but those males that had observed a pre-built nest of material of their non-preferred colour lost their material-colour preference altogether.

From a sequential pattern, temporal adjustments emerge in hummingbird traplining.

Animals that feed from resources that are constant in space and that refill may benefit from repeating the order in which they visit locations. This is a behavior known as traplining, a spatial phenomenon. Hummingbirds, like other central-place foragers, use short traplines when moving between several rewarding sites.