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THE WILSON JOURNAL OF ORNITHOLOGY • Vol. 124. No. 3. September 2012 
pattern exhibited by the other two species of 
lodopleuro. Juveniles, as far as is known, 
resemble females even in Schiffomis. the most 
closely related genus to Laniocera and Laniisoma , 
although Kirwan and Green (2011) speculate that 
Varzea Schiffomis (5. major) with drop-shaped 
bluish-gray spots on the greater wing-coverts 
perhaps represents the juvenile plumage. Thus, 
the general pattern of juvenile plumage observed 
in Tityridae, as for most birds, is less conspicuous, 
contrasting dramatically with those plumages we 
describe for L livpopyrra and L. elegans. 
The evolutionary relationship between L. hypo * 
pyrra and L. elegans. when considered with respect 
to juvenile plumages of other Tityridae, strongly 
suggests the described state is a synapomorphy of 
the clade Laniocera-Laviisoma. Thus, we expect 
the first plumage (juvenile) of Laniocera rufescens 
should possess a similar plumage pattern. This 
species’ nest has not been found (Fitzpatrick et al. 
2004. Kirwan and Green 2011), but there are 
descriptions of so-called juvenile plumage in the 
literature. Some authors have suggested the 
juvenile is grayer on the head with black fringes 
to the greater and median wing-coverts, and 
randomly black-spotted body-sides (Restall et al. 
2006), while the immature is reported to resemble 
the female, albeit with more prominent wing and 
underparts markings, a grayish wash to the crown, 
foreneck, lower back and rump and, at times wilh 
some sparse black spotting on the breast with dull 
gray bands extending from the neck-sides to the 
undertail coverts (Welmore 1972. Hilty and Brown 
1986. Fitzpatrick et al. 2004 ). We suspect that all 
of the descriptions concerning non-adult plumages 
of L. rufescens refer to plumage states older than 
juvenile given the documented juvenile plumages 
of L. hypopyrra and Laniisoma elegans described 
in this paper. 
Ecological Function. —Coloration among bird 
species is often subject to differences, occasionally 
extreme, dependent on sex. season, and age. The 
general pattern related to plumage of immatures, 
regardless of sex. is characteristically dull, or 
inconspicuously marked, and closely resembling 
the plumage of the adult female (Kilner 2006). 
Predators can threaten birds of all ages, but they 
pose the greatest threat to eggs, nestlings, and 
young juveniles (Dumbacher and Pruett-Jones 
1996), which are more vulnerable than adults. 
1 he evolution ol the inconspicuousness of juvenile 
plumage is considered to be a consequence of 
selection for crypsis (Kilner 2006) in response to 
predation pressure by visually oriented predator}' 
species (e.g.. raptors and primates). 
The juveniles of Laniocera hypopyrra and 
Laniisoma elegans. in contrast to the general 
pattern of plumage color observed in juvenile 
birds, possess highly conspicuous plumages, 
while adults of both species are either very 
inconspicuous or less conspicuous, respectively. 
Snow (1982) suggested the nestling of Lanii¬ 
soma elegans had evolved to appear like moss 
covered by fruits, and subsequently postulated 
this remarkable plumage represents an adapta¬ 
tion to the species using an exposed nest site 
(Snow 2004). However, we consider the patterns 
observed in the juveniles of these two species 
(and the nestling of Laniisoma) strongly suggest 
either a chemical defense (toxic and/or unpalat¬ 
able) or Batesian mimicry (e.g.. of a large, hairy 
caterpillar). A general pattern of conspicuous 
colors, exhibited by some birds, may function as 
a signal of Ymprofitability’ to predators (Baker 
and Parker 1979). Chemical defense (toxic and 
unpalatable) in some taxa is correlated with 
aposematic coloration (Cott 1940, Colt and 
Benson 1970. Guilford 1990, Dumbacher and 
Pruett-Jones 1996). Some non-toxic or palatable 
species also present morphological and behav¬ 
ioral characters similar to those of toxic or 
unpalatable species by Batesian mimicry (Dia¬ 
mond 1982. Borloloti 2006). Additionally, it has 
often been suggested that warning colors can 
also have a disruptive (Tullberg et al. 2005). or 
a distractive function (Stevens and Merilaita 
2009). Further work is needed to test the 
alternative hypothesis regarding the ecological 
role of juvenile plumage of Laniocera and 
Laniisoma. 
ACKNOWLEDGMENTS 
Personnel from CNEC Engenharia Ltd. supported 
FMH’s fieldwork. We are grateful to Manuel Santa 
Brigida who prepared the specimens collected during 
the same fieldwork, and Alexandre Aleixo from MPEG, 
who provided the specimen loan. Jeremy C. Minns is 
warmly thanked for sharing his observations of the 
juvenile of luiniisoma elegans. GMK is grateful to Robert 
Prys Jones, Mark Adams, and Hein van Grouw at The 
Natural History Museum, Tring. for permission to study 
relevant specimen material housed there. We are grateful to 
Tomas Sigrist, who kindly ereated the illustration of 
Laniocera hypopyrra, and the Biodiversity Heritage Library 
for allowing us to reproduce the image of Laniisoma 
elegans. Clait E. Braun. John M. Bates, and an anonymous 
referee provided useful comments on the submitted 
manuscript. 
