Journal of Thermal Biology 47 (2015) 7–12

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Journal of Thermal Biology

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The Rufous Hornero (Furnarius rufus) nest as an incubation chamber

Felipe L.S. Shibuya a,n, Talita V. Braga a, James J. Roper a,b

a Programa de Pós-Graduação em Ecologia e Conservação, Universidade Federal do Paraná, Curitiba, Paraná, Brazilb Programa de Pós-Graduação em Ecologia de Ecossistemas, Universidade de Vila Velha, Vila Velha, Espírito Santo, Brazil

a r t i c l e i n f o

Article history:Received 19 July 2014Received in revised form30 October 2014Accepted 30 October 2014Available online 4 November 2014

Keywords:Incubation chamberIncubation-foraging trade-offTemperatureNest functionReproduction

x.doi.org/10.1016/j.jtherbio.2014.10.01065/& 2014 Elsevier Ltd. All rights reserved.

espondence to: Universidade Federal do Pararaná 81.531-980, Brazil.ail address: felipe.shibuya@gmail.com (F.L.S. S

a b s t r a c t

Foraging and incubation are mutually exclusive activities for parent birds. A trade-off is generated when acombination of food availability and temperature regulation force birds to choose one and neglect theother, at least temporarily. The Rufous Hornero builds large, oven-like, mud nests, the evolutionary causeof which remains unknown. We tested that temperature variation inside the nest is that which is ex-pected if one function of the nest were for temperate regulation. If so, this would suggest that the nestworks as an incubation chamber (but which now may serve more than one function). We divided nestsinto two natural treatments: nests that received more continuous direct sunshine (sun), and those thatreceived less direct sunshine, due to shade from trees or buildings (shade). Thermometer data loggerswere placed in the nest cavity and outside, in the shade of the nest, and temperature was measured every10 min. We predicted that temperatures would consistently be higher and less variable in nests thanoutside nests. Also, at higher ambient temperatures the nest would function better as an incubationchamber as a consequence of having evolved in a hotter climate. Thus, in Curitiba, where temperaturesare lower than where the species (and nest) evolved, nests in greater sunshine should have thermalcharacteristics that support the incubation chamber hypothesis. Predictions were supported: with Re-peated Measures ANOVA and t-tests, we found that temperatures were more constant and higher innests, especially when in the sun, and as the season progressed (hotter ambient temperatures). Weconclude that the large mud nest of the Rufous Hornero works as an incubation chamber that likelyevolved to help resolve the incubation-foraging trade-off in the very seasonal and hot regions where thebird evolved. Thus, as an incubation chamber, the nest allows the bird to forage rather than incubatethereby resolving the foraging-incubation trade-off and potentially favoring survival of the adults andtheir foraging for, rather than incubating, their young. Counter intuitively, in the study area, where theRufous Hornero is a recent arrival following deforestation, and where the climate is very different fromwhere it evolved, there seems to be no clear thermal benefits for the birds from their energeticallyexpensive mud nest.

& 2014 Elsevier Ltd. All rights reserved.

1. Introduction

Birds build a wide variety of nest types and presumably eachtype of nest evolved as a response to specific selective forces, suchas climate and predation avoidance (Deeming, 2002; Gill, 2007;Hansell, 2000). While we assume that nests are advantageous, thegreat variety of nest types is still difficult to explain. For example,by building a complex nest, the Hooded Oriole (Icterus cucullatus)may avoid nest parasitism (Hardy, 1970). Microclimate may beimportant for some birds (Blem and Blem, 1994; Pinowski et al.,2006) but not others (Wiebe, 2001), and clearly climate is a po-tentially important alternative that should be considered. Also,

ná, Caixa Postal 19031, Cur-

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nests may influence the chances of nest predation (Martin, 1993;Martin and Li, 1992; Martin and Roper, 1988) which must beconsidered when analyzing nest function. While these potentialnest “functions” seem reasonable, it is difficult to attribute a clearfunction to any particular nest type because they all “work”-that is,they all serve the purpose of taking eggs to fledglings. An exampleis the extremely variable nests in the family Furnariidae, all ofwhich “work” (Zyskowski and Prum, 1999).

Reproduction is a time and energy-consuming process andincludes nest building, egg laying, incubation and rearing of eggsand nestlings, and post fledging care (Lack, 1968). Food abundanceprior to egg laying is obviously very important (Martin, 1987;O’Connor, 1979; Ricklefs, 1974). Following egg laying, conflicts mayarise between caring for nests (with eggs or nestlings) and fora-ging by the adults, because incubation and foraging are mutuallyexclusive activities (Conway and Martin, 2000a; DuRant et al.,2010; Martin, 1987). In this respect, nesting may be a form of

Fig. 1. Map showing where the study took place in Curitiba, in southern Brazil.Also, showing Cuiabá, in the state of Mato Grosso, which is within the Pantanalregion of Brazil where the species probably originated prior to deforestation. Thisillustrates the difference between the two regions: continental interior at tropicallatitudes (Cuiabá) and relatively near the ocean, subtropical (Curitiba).

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trade-off between the needs of the eggs and young and those ofthe parents while they care for young. Thus, we expect that anyvery large and energetically costly nest should provide a com-mensurate large and consistent benefit to have been favored byevolution through natural selection.

The Rufous Hornero (Furnarius rufus) builds a very large, oven-shaped, mud nest (hence the name hornero, Spanish for baker,because of the use of the oven, horno) that may take days tomonths to build (Fraga, 1980; Sick, 1997; pers. obs.). The evolvedpurpose of this complex nest as an adaptation remains untested,while both microclimate and nest-predation-avoidance seem to belikely possibilities. Indeed, answering this question is itself aproblem because the current distribution of the species is nowmuch larger than its original distribution as a consequence ofdeforestation and other modifications of the environment (Sick,1997). Nonetheless, the nest of the hornero apparently evolved inthe savannas of central South America (Cerrado, Pantanal andChaco regions of central and southwestern Brazil and adjacentBolivia, Paraguay and Argentina; Sick, 1997). Savannas are seaso-nal, with the heaviest rains concentrated over a relatively shorttime interval and as a consequence, they also have an extendeddry season (Raven et al., 2012). Thus, we suggest that the mudoven nest of the Rufous Hornero is an adaptation for thisenvironment.

Two untested suggestions for the complex nest are climate andnest predation/parasitism avoidance (Fraga, 1980; Hermann andMeise, 1965; Vaz-Ferreira et al., 1992). While nest predationavoidance may indeed be important today, here we explain why itis unlikely to have been the cause of the evolution of the mud nest,and thus, if nests interfere with predation/parasitism, this is not anadaptation but rather an exaptation (sensu Gould and Vrba, 1982).A partial mud nest, a cup or bowl, for instance, will not affordprotection from predation/parasitism. Thus, if the nest evolvedfrom simple to complex, then the intermediate stages would nothave provided anti-predation/parasitism benefits, only the fin-ished product would have. Also, the size of the entrance to thecavity (ca. 11 cm diameter, Hermann and Meise, 1965) is largeenough that many potential predators may easily enter nests, in-cluding small mammals, other birds and snakes. Today, as an ex-aptation, the nest may reduce predation/parasitism from somepredators/parasites, and nest predation has been observed onlyonce (Fraga, 1980). Thus, we suggest that reduction of nest pre-dation/parasitism avoidance is unlikely as the evolutionary causeof the mud nest.

Climate control (i.e., an incubation chamber in which climate iscontrolled to favor growth and development of eggs and young,Stoleson, 1999; Stoleson and Beissinger, 1999; Veiga and Viñuela,1993), as yet untested, is a more logically consistent hypothesis forthe evolution of this nest, following the logic of evolution fromsimple to complex. A partial mud nest (a cup or bowl) may notinfluence predation/parasitism, but with only mud walls it willmodify the microclimate of the nest (Hermann and Meise, 1965;Vaz-Ferreira et al., 1992). Thus, natural selection could favor theever-increasing size of the mud nest until it became completelyenclosed, at which time predation avoidance may come into play.

In Argentina, Rufous Hornero young hatch asynchronously(Fraga, 1980), while in cooler Curitiba, in southern Brazil, they donot (Rodriguez and Roper, 2011). If the nest functions as an in-cubation chamber, this would generate asynchronous hatching aseggs would begin development when temperatures inside the nestare high. Also, this frees the parents so that they may forage in-stead of incubate. This can explain the difference between Ar-gentina and Paraná—that is, if birds begin to incubate on the pe-nultimate egg, as is common in synchronously hatching birds, thenwhen hornero nests are hot (Argentina), young will begin to de-velop as eggs are laid, generating facultative asynchronous broods,

while in cooler nests (Paraná, southern Brazil), development willonly commence with incubation. Starvation and abandonment ofnestlings (as much as 50%) are relatively common in the RufousHornero (Fraga, 1980; Rodriguez and Roper, 2011). Asynchronoushatching, in some birds, may reduce peak demand at nests (Bryant,1978; Budden and Beissinger, 2005; Mock and Schwagmeyer,1990; Skagen, 1988), but is uncommon among passerine birds.Thus, the tendency of the Rufous Hornero to asynchronoushatching may be a benefit of the mud nest as an incubationchamber.

With these considerations in mind, in this study, using a nat-ural experiment and temperature data-loggers, we test whethernests of the Rufous Hornero function as incubation chambers. If so,we predict that temperatures will be higher and more constantwithin the nest than outside the nest. Additionally, we suggestthat due to that temperature differential, the adult birds are freedfrom incubation which then allows them to forage. Next, as anincubation chamber, asynchronous hatching is a result of constanthigh temperatures within the nest and not due to incubation be-havior (passive asynchrony). We discuss the consequences of thesepredictions in the context of a how old adaptations may en-igmatically fit in new environments when species extend theirdistributions as humans modify the environment.

2. Material and methods

2.1. Study area

We studied thermal characteristics of Rufous Hornero nests onthe campus of the Polytechnical Center of the Federal University ofParana, in the city of Curitiba (25°41′67″S, 49°13′33″W, Fig. 1),Parana, Brazil, during the 2010 breeding season. The campus re-sembles a savanna in that it has broad grassy areas with rows andclumps of trees. Climate is humid subtropical, with cool,

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somewhat drier winters (�1.3 °C minimum) and warm, wettersummers 32.5 °C, (IPPUC, 2001; Maack, 2002). There is a well-defined rainy season, a well distributed during all months of theyear rains. The average annual relative humidity is 81.5% and theaverage annual rainfall is 1451.8 mm, still occurring an average of179 rainy days during the year (Maack, 2002). To better under-stand the relationship between temperatures at the nest and ofthe environment, we obtained daily temperatures (maximum,minimum) for the study period from the Meteorological System ofParaná on the university campus.

2.2. Study species

The Rufous Hornero (Furnarius rufus Gmelin 1788) is commonin open and residential areas throughout Curitiba and nearby ruralareas. As described, nests are large and conspicuous. The hornerois monogamous, territorial and a permanent resident of theirterritories. The earliest records of the Rufous Hornero in Curitibafound in the literature date back to the mid 1980s (COA, 1984).Horneros feed on all kinds of invertebrates as well as some an-thropogenic foods (Fraga, 1980; Sick, 1997; pers. obs.). On campus,we have seen horneros visiting cantinas and garbage and feedingon pieces of bread, french fries and other items.

The nesting cycle in Curitiba usually begins in late August orearly September but may sometimes start earlier and usually endsin December, with occasional active nests in January (Rodriguezand Roper, 2011). Birds may be seen building nests throughout theyear when mud is available. In our observations over several years,birds never use nests for any purpose other than reproduction,even though they build when not breeding. Nest construction cantake from days to months, but during the breeding season, theyhave been seen to build an entire nest in less than two weeks. Eggsare laid every other day and clutch sizes range from 2 to 5, withfive eggs only seen in territories with anthropogenic food sources(in the form of dog or cat food, J. J. Roper, unpubl. data). Incubationvaries around 17 days and in Argentina, hatching is asynchronous(Fraga, 1980). Nestlings remain in the nests for 24–26 days (oc-casionally up to 30 days, pers. obs.). Upon fledging, young birdsremain in the natal territory for weeks to months and sometimesuntil the next breeding season.

Fig. 2. Schematic diagram showing how the Thermochrons iButtons DS1921G was placpiece of wall was removed. The plastic-covered thermometer was attached to a screw psealed with mud.

2.3. Experiment

In our experiments, we used nests that were accessible from anextension ladder of 7.5 m. Because of the difficulty of measuringincidence of sunlight-on-nests throughout the day and over the timeinterval of nesting as a continuous variable, we divided nests intotwo treatments, sun and shade treatments, with respect to sunshineduring the course of the day. Nests in the sun treatment were thosenests that were clearly in direct sunlight for 44 h day�1. The shadetreatments were otherwise (suno4 h day�1). A priori, we predictedthat nests in the sun were more like nests in the savanna habitatwhere these birds originally occur, and so we predicted that thermalbehavior of those nests would most clearly be as incubators.

To compare temperatures in and out of nests in these twotreatments, we placed temperature data loggers (ThermochronsiButtons DS1921G70.5 °C precision, hereafter thermometer) in-side and outside of experimental nests and recorded temperaturesevery 10 min. We originally wished to leave the thermometerswith the eggs in the nests to also record adult incubation behavior.Thermometers were placed at nests (inside and outside) whenpossible, just prior to egg-laying (as judged by parental bird be-havior), where they usually remained until fledging. Some fewnests failed prior to fledging and occasionally thermometers wereplaced in nests at other times (see Section 3). When we discoveredadult birds removed the thermometers, we began fixing thethermometers to the interior nest wall (Fig. 2). To protect themfrom humidity, we sealed them in plastic that was then attached tothe head of a screw. We drilled a hole in the nest wall, throughwhich we passed the thermometer on the end of the screw, andthen sealed the hole with mud. The nut of the screw was on theoutside of the nest and the thermometer on the inside, and thescrew, sealed within the mud wall, was secure. Temperaturereadings are of the internal chamber of the nest. Outside tem-peratures were recorded by thermometers also covered in plasticand attached by a thumbtack in the shade and near the nest(usually beneath, always less than 50 cm). Thermometers have amemory life-span of about two weeks when registering tem-perature every 10 min and so were left at nests for two weeks, atmost.

ed within the nest: (A) the nest was first drilled with a large hole-boring bit, (B) thelace through the piece of wall, (C) which was then replaced into the hole, (D) and

Fig. 3. Temperatures inside (A, B) and outside (C, D) nests, in the sun (A, C) and theshade (B, D), comparing ambient temperatures (ordinate) with temperaturesmeasured at nests (abscissa). Ambient temperatures were measured at the Me-teorological System of Paraná on the Federal University of Paraná Campus andtemperatures measured at nests were measured by Thermachronss (see text). Thenull relationship between the two (that of no thermal influence of the nest) isindicated by the diagonal lines (one-to-one relationship). Outside the nests (C, D)minimum temperatures follow that relationship while maximum temperatures atnests tend to be greater. Finally, temperatures within nests always tend to begreater than those measured at the station.

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2.4. Statistical analysis

We compared daily maximum and minimum temperaturesfrom the Meteorological System of Paraná with daily maximumand minimum temperatures in the sun and shade treatments,inside and outside of nests, using paired t-tests. We anticipatedthat outside temperatures (since they were shaded by the nest)would be similar to those of the weather station, while insidetemperatures would be more constant and, at least in the suntreatment, greater than those of the weather station. To testwhether nests work as incubation chambers, we predicted that(1) average temperatures inside the nest are consistently greaterthan outside the nests, (2) temperatures inside nests are lessvariable than outside nests (comparing coefficients of variation,CV, using paired t-tests) (3) nests in the sun have higher and moreconstant temperatures than nests in the shade, and (4) during thehottest months, (4a) temperatures in nests are closer to incubationtemperatures, more so in the sun treatment, and (4b) tempera-tures are less variable inside nests, more so in the sun treatment.We tested these predictions with a series of Repeated MeasuresAnalysis of Variance comparing temperatures inside/outside andsun/shade and over time. We used the 08:00–18:00 h time intervalfor this comparison because thermal characteristics during day-light should be those that reflect where the nests evolved, andbecause at night, an adult bird will incubate. Also, the trade-offbetween foraging and incubation is only relevant during the daywhen foraging is possible. We tested for consequences of thethermal characteristics as a reduction in incubation time and thenesting cycle in the sun treatment by comparing the number ofdays from egg-laying to hatching, and the number of days fromhatching to when fledging occurred, by t-tests.

All analyses were performed using the programs R 2.13.1 andJMP 6, and we assumed an error rate of 5% in all tests.

Fig. 4. Comparison of the variability of temperatures inside and outside of thenests in the sun and shade, using the coefficient of variation as the indicator ofvariability. Both one-tailed t-tests show that temperatures vary more outside (bothPo0.05).

Table 1Comparison of maximum temperatures (°C) between sun and shade treatmentsand inside and outside treatments, by month during daylight hours, using RepeatedMeasures Analysis of Variance.

Month Inside Outside Fa

Sun Shade Sun Shade Sun/shade In/out

October 24.7 23.3 23.0 21.9 15.6 7.6November 29.0 27.6 27.5 24.6 17.9 66.2December 28.9 24.4 24.4 22.4 15.5 17.4

a All Po0.05, numerator degrees of freedom¼1 in all cases, denominator de-grees of freedom: October—331, November—537, December—143.

3. Results

As predicted, temperature variability within nests was less thanthat outside of nests (CV, one-tailed t-tests, sun: t¼3.78, df¼26,P¼0.01, shade: t¼1.76, df¼32, P¼0.04, Figs. 3 and 4). Also, thetemperature inside nests tended to be greater than outside andtemperatures in nests in the sun were greater than in nests in theshade (Table 1, Figs. 4 and 5).

During October, when ambient temperatures were relativelycool, the differential inside of nests is less, but nonetheless at mid-day the maximum temperatures in the nests are, on average,�3 °C warmer than outside. In November, when temperatures aregreater, the maximum temperatures in and outside of nests weresimilar, while minimum temperatures were greater inside thenests. Finally, in December when average temperatures werewarmer, temperature inside nests tended to be greater in the sun(both maximum and minimum) than in the shade, and minimumtemperatures in the shade inside nests tended to be greater thanoutside temperatures (Table 1, Fig. 5).

Do the birds receive any benefit from this temperature differ-ential? In comparing the timing for incubation and the entirenesting cycle we found that duration was similar in both, in-cubation (mean sun¼22.0 days, mean shade¼22.3 days, t¼0.60,df¼9, P¼0.28) and entire nesting period (mean sun¼47.0 days,mean shade¼47.5 days, t¼0.38, df¼7, P¼0.35). Thus, no reduc-tion in the nesting interval was found for nests in the sun. Neithernest predation nor nest parasitism caused the failure of any nestduring the course of this study, nor during previous studies (Ro-driguez and Roper, 2011).

Fig. 5. Comparison among mean maximum and minimum monthly differential(temperature difference of our data loggers and the weather station) temperatures(error bars indicate the 95% confidence intervals) by treatment (sun, shade) andposition (in, out) at Rufous Hornero nests. When temperatures at nests are warmerthan the weather station, the values are above the zero line (positive) and the meanmonthly temperature at the station is given in the middle of the lower graph.Outside, and minimum temperatures tend to be closer to those of the weatherstation (exception in October), while temperatures inside nests tend to be warmer(exception also in October). See Table 1.

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4. Discussion

The large, oven-like, mud nest of the Rufous Hornero hasthermal characteristics that supported the predictions of itsfunction as an incubation chamber. Temperature inside the nesttends to be higher and less variable, nests in the sun even more so,and the differences are greater at higher ambient air temperatures.We suggest that this indicates that, in the even hotter regions inwhich the nest evolved, the nest should work most efficiently asan incubation chamber, and indeed, may even prevent the nestfrom getting too hot by providing shade (Ar and Sidis, 2002; Ta-zawa and Whittow, 2000). However, in the more temperate cli-mate of Curitiba, where they only relatively recently arrived (as aconsequence of deforestation), birds may reap little or no benefitfrom this temperature differential because the climate here is nothot enough.

The lack of measurable benefit in the reduction of the nestingperiod for the Rufous Hornero is not surprising because incubationand nestling periods are typically not very plastic (Williams, 2012).Nestlings hatch synchronously here, in contrast to Argentina(Fraga, 1980; Rodriguez and Roper, 2011). This suggests that thehornero has a typical behavior of most passerines of beginningincubation on the penultimate egg and which normally results insynchronous hatching (Clark and Wilson, 1981) and that the in-creased internal temperature of the nest is still below that whichmay initiate or maintain development. Temperatures in the nest,while tending to be warmer than outside, rarely reached the op-timum developmental temperature range of 37–38 °C (Deeming,2002; Gill, 2007) and ambient air temperature was also lower.Thus, while the temperatures were higher, as predicted, they werenot high enough to provide a clear benefit by incubating eggs and

young and decreasing the nesting cycle or causing hatchingasynchrony.

Benefits that may not accrue here but that we predict for thearea of origin are consequences of higher temperatures and shouldbe two-fold. First, due to high temperatures inside the nest, de-velopment should begin at the time eggs are laid, causing hatchingasynchronously which, in turn, allows the peak demand of theoffspring to be spread over a wider time interval, thereby reducingthe daily demands on the parents (Clark and Wilson, 1981; Richter,1982; Skagen, 1988). In Curitiba nestling starvation is relativelycommon (Rodriguez and Roper, 2011), and so increased nestlingsurvival should be favored by hatching asynchronously if the peakdemand hypothesis is correct. Second, by increasing the tem-perature in the nest, adults may leave the nests more often andforage for longer time intervals, perhaps allowing them to recoverfrom reproductive costs of incubation or of foraging to feed young.Thus, evolution of the nest may have, in part, been driven by theincubation-foraging trade-off (Conway and Martin, 2000b).

It is interesting that the Rufous Hornero has been able to ex-pand its range, given the cost of its nest, especially when that nestno longer fulfills its evolved function in regions with more mod-erate climates. As in Northern Flickers (Colaptes auratus), havingno relationship between temperature and nesting success (Wiebe,2001), the lack of a relationship does not necessarily imply that arelationship never existed. In Curitiba, the only five egg clutchesfound were those in territories with anthropic sources of food andmud (J. J. Roper, unpubl. data). Indeed, adults were seen carryingdog food to feed young, while in other territories of lower quality,adults were seen gathering ants to feed young (J. J. Roper, pers.obs.). Thus, we suspect that the Rufous Hornero was able to in-crease its geographic distribution because of anthropic interac-tions, such as watered lawns (providing the mud-grass mix theyuse for building) and sources of food. Therefore, while the cost tobuild a nest is still large, apparently that cost of nest constructionis relatively easily paid in anthropic environments.

If our hypothesis is correct, then why does the Rufous Horneronot consistently choose nest sites in sunny locations? We suggestthat in the region of origin, due to high, constant temperatures, allnest sites are hot, and so no selective pressure existed for nest-siteselection to control temperature over that furnished by the nestitself. Indeed, it is possible that, in the region of origin, very sunnysites may get too hot (Grant, 1982).

5. Conclusions

We demonstrate that the incubation chamber hypothesis isconsistent with the data, which suggests that the evolved functionof the Rufous Hornero nest is for temperature regulation. Wesuggest several reasons for such a chamber, especially in favor offoraging over incubation in the incubation-foraging trade-off, butalso to generate asynchronous hatching in an otherwise synchro-nously-hatching bird. Despite these potential benefits, none in factprovides a benefit for the Rufous Hornero in the study area (andprobably other regions they have come to occupy due to defor-estation), which suggests that the bird is now burdened with acost of reproduction that is different and likely to be greater(nestling mortality is common) than in its area of origin (Ro-driguez and Roper, 2011). Anthropogenic sources of food and mudmay be the driving forces that permit the increase in the RufousHornero geographical distribution.

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Acknowledgments

We would like to thank Ricardo A. S. Cerboncini and RafaelaBobato for their invaluable assistance in the field. Also, we thankRegina Helena Ferraz Macedo and João Batista de Pinho for theirreviews and suggestions. Meteological System of Paraná providedthe temperature data from the weather station at the UniversidadeFederal do Paraná. This study was funded by graduate fellowshipsfrom the Federal University Restructuring and Expansion Program(Programa de Reestruturação e Expansão das Universidades Federais,REUNI) (Grant no. 40001016), that made this study possible.

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Felipe is a doctoral student in Ecology and Conservation atthe Federal University of Paraná (where he also received hismasters degree) and is interested in population dynamicsof birds.

ecology, conservation, birds and parental care.

Talita is also a doctoral student in Ecology and Conserva-tion at the Federal University of Paraná (where she alsoreceived her masters). Talita is interested in behavioral

and taught in the USA, Costa Rica, Panama, Venezuela, Peru

James (Jim, advisor of Felipe and Talita) has a B.S. (1978,Oklahoma State University) and M.S. (1989, Arizona StateUniversity) both in Zoology and Ph.D. (1996, University ofPennsylvania) in Ecology and Evolution. Having worked

and Brazil. Jim is interested in population dynamics andhow they vary locally, regionally and globally. Jim currentlyteaches and advises grad students at the Universidade VilaVelha in the Brazilian state of Espírito Santo and at theUniversidade Federal do Paraná in the state of Paraná.