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Plumage convergence in tyrant flycatchers: A 1
tetrachromatic view 2
3
A thesis submitted to the Department of Biological Science of the 4
Universidad de los Andes in partial fulfillment of the requirements for the 5
degree of Bachelor of Science in Biology 6
7
8
María Alejandra Meneses-Giorgi 9
Laboratorio de Biología Evolutiva de Vertebrados 10
Departamento de Ciencias Biológicas 11
Universidad de los Andes 12
13
Advisor: 14
Daniel Cadena, PhD 15
Full Professor 16
Departamento de Ciencias Biológicas 17
Universidad de los Andes 18
19
20
ABSTRACT 21
Convergent evolution is the process through which different evolutionary lineages 22
independently evolve similar features. Phenotypic convergence has been linked 23
with selective pressures including predation and competitive interactions. Social 24
mimicry may lead to convergent evolution when interactions with conspecifics and 25
heterospecifics drive evolution towards similar phenotypes. Several hypotheses 26
accounting for convergence based on mechanisms of social mimicry exist, but 27
evaluations of how similar species are given the visual system of receptors has 28
been ostensibly missing from tests of such hypotheses. We used phylogenetic 29
methods, plumage reflectance measurements of six species of tyrant flycatchers 30
(Passeriformes, Tyrannidae) with strikingly similar plumage patterns, and models 31
of avian vision to evaluate the efficacy of visual deception and therefore the 32
plausibility of hypotheses potentially accounting for plumage convergence involving 33
mimicry. We found plumage similarity resulted from convergence and may have 34
been favored by selective pressures exerted by predation because putative models 35
and mimics species were indistinguishable by visually oriented raptors. We reject 36
social mimicry hypotheses as an explanation for the aparent similarity between one 37
of the putative model species and putative mimics because deception seems 38
unlikely given the visual system of passerines visual system. Nonetheless, 39
plumage convergence may have been favored by competitive interactions with 40
other putative model species or with other smaller species of passerines. 41
Experiments and behavioral observations are necessary to better characterize 42
social interactions among our study species and to test predictions of alternative 43
hypotheses posed to account for mimicry. 44
45
RESUMEN 46
La evolución convergente es el proceso mediante el cual diferentes linajes 47
evolutivos independientemente evolucionan características similares. La evolución 48
convergente ha sido relacionada con presiones de selección como la depredación 49
y las interacciones de competencia. El mimetismo social puede llevar a evolución 50
convergente cuando las interacciones competitivas con individuos coespecíficos y 51
heteroespecíficos impulsan la evolución hacia fenotipos similares. Existen varias 52
hipótesis que dan cuenta de la convergencia dado el mimetismo social, pero 53
estimaciones de qué tanto se parecen las especies involucradas dado el sistema 54
visual de especie receptoras han estado ausentes de los trabajos que evalúan 55
dichas hipótesis. En este estudio usamos métodos filogenéticos, medidas de 56
reflectancia de seis especies de tiránidos (Passeriformes, Tyrannidae) que 57
presentan plumajes similares y modelos visuales de aves para evaluar la eficacia 58
del engaño visual y, por ende, la plausibilidad de hipótesis que plantean que la 59
convergencia en el plumaje ha surgido por mimetismo social. Encontramos que la 60
similitud en el plumaje es producto de convergencia, que pudo ser favorecida por 61
la presión de selección ejercida por los depredadores pues las especies modelo e 62
imitadoras hipotéticas son indistinguibles para aves rapaces que se orientan 63
visualmente. Rechazamos las hipótesis de mimetismo social como una explicación 64
de la aparente similitud entre una de las especies modelo y los imitadores 65
hipotéticos debido a que el engaño es poco probable dado el modelo visual de los 66
Passeriformes. Sin embargo, la convergencia en el plumaje pudo haber sido 67
favorecida por interacciones competitivas con la otra especie modelo putativa o 68
con otras especies passeriformes más pequeñas. Es necesario hacer 69
experimentos y observaciones de comportamiento para caracterizar mejor las 70
interacciones sociales entre nuestras especies de estudio y para probar 71
predicciones de hipótesis alternativas planteadas para explicar el mimetismo. 72
73
Keywords: Convergence, coloration, social mimicry, visual models, interespecific 74
social dominance mimicry. 75
76
INTRODUCTION 77
Convergent evolution, the process through which two or more distinct lineages 78
independently acquire similar traits, reveals that the paths of evolution are not 79
infinite, but may be rather restricted. Convergence may happen rapidly or over the 80
course of millions of years either by random drift or more likely because a given 81
phenotypic trait is repeatedly favored by natural selection in a particular 82
environment (Endler, 1986; Losos et al., 1998). Likewise, convergence may also 83
occur due to biases in the production of phenotypic variation such as shared 84
developmental constraints (Brakefield, 2006; Losos et al., 1998; Price & Pavelka, 85
1996). A well-studied form of convergent evolution is mimicry, in which one species 86
(the mimic) evolves to resemble another species (the model), often to deceive a 87
third species (the receptor; McGhee, 2012). 88
89
There are numerous examples of phenotypic convergence among birds (Cody & 90
Brown, 1970; Davies & Welbergen, 2008; Jønsson et al., 2016; Laiolo, 2017; 91
Leighton et al., 2018; Lopes et al., 2017; Prum, 2014; Stoddard, 2012), and several 92
scientists have proposed hypothesis to explain this phenomenon in the context of 93
mimicry (Barnard, 1979, 1982; Diamond, 1982; Moynihan, 1968; Prum, 2014; 94
Prum & Samuelson, 2012, 2016). Among leading ideas proposed to account for 95
phenotypic convergence in birds, the social mimicry hypothesis (Moynihan, 1968) 96
posits that convergent similarity in traits like coloration and plumage patterns may 97
evolve to promote efficient communication maintaining cohesion both among 98
conspecifics and heterospecifics in mixed-species flocks. A variant of this 99
hypothesis posits that rather than maintaining cohesion of mixed flocks, social 100
mimicry serves mainly as an antipredatory adaptation because predation 101
eliminates conspicuous or atypical individuals from populations, thereby promoting 102
phenotypic uniformity (Barnard, 1979). How atypical an animal is in this context 103
must be examined relative to the background (Gomez & Théry, 2007); if a predator 104
considers a whole mixed-species flock as the background, then any species 105
forming a distinct minority within it may be a preferred prey, resulting in a selective 106
pressure favoring homogeneity (Mueller, 1971). Therefore, the efficacy of social 107
mimicry to reduce predation (Barnard, 1979) depends on the extent to which 108
predators may perceive mixed flocks as homogeneous, which ultimately relies on 109
the acuity of their visual system. 110
111
An alternative explanation for mimicry not focusing on predation but still 112
considering social interactions suggests that mimicry may serve two purposes: (1) 113
mimics may escape attack from model species of larger body size, and (2) mimics 114
may deceive species of smaller size and scare them off without further effort 115
(Diamond, 1982). Along the same lines, Prum & Samuelson (2012) further 116
proposed the Interspecific Social Dominance Mimicry (ISDM) hypothesis, which 117
posits that, given interference competition, smaller species evolve to mimic larger, 118
ecologically dominant competitors, to deceive them and thereby avoid attacks. For 119
this mechanism to be plausible, individuals of the mimic species must be confused 120
by individuals of the model species as if they were conspecific based on pictorial 121
cues like shape, color and plumage patterns regardless of differences in body size 122
(Leighton et al., 2018; Prum, 2014; Prum & Samuelson, 2012, 2016). Therefore, 123
the efficacy of this form of mimicry critically depends on the visual system of model 124
species. 125
126
Explicit consideration of the efficacy of visual deception given avian visual models 127
has been ostensibly missing from analyses, limiting our ability to assess the 128
plausibility of various hypotheses posed to account for mimicry. Birds have visual 129
pigments enabling them to acquire information from red, green and blue 130
wavelengths (like humans), but they are also capable of acquiring information from 131
ultraviolet wavelengths with an additional pigment. Also, each of the avian 132
pigments is paired with a particular pigmented oil droplet type, which results in 133
better spectral discrimination relative to other vertebrates (Cuthill et al., 2000). The 134
ability to distinguish colors varies among birds, however, with a pronounced 135
difference in the absorbance peak of the ultraviolet sensitive (UVS-type) cones 136
present in Passeriformes and Psittaciformes, and the violet sensitive (VS-type) 137
cones present in all other non-passerines including raptors (Håstad et al., 2005). 138
Thus, a crucial question one must answer to gauge support for hypotheses 139
attempting to account for mimicry is whether phenotypic similarities between 140
species perceived by humans are sufficient to deceive birds including predators, 141
competitors, and putative models given properties of their visual systems. 142
143
We used plumage reflectance measurements of six species of tyrant flycatchers 144
(Passeriformes, Tyrannidae) with strikingly similar plumage patterns to evaluate 145
the efficacy of visual deception and therefore the plausibility of mimicry hypotheses 146
potentially accounting for phenotypic convergence. The species we studied are 147
part of a hypothetical mimicry complex posited to be an example of ISDM 148
consisting of two model species of large body size and a variety of putatively mimic 149
species of smaller size (Prum 2014). We first reconstructed ancestral character 150
states on a molecular phylogeny to evaluate whether plumage similarity is indeed a 151
result of convergence and not of common ancestry in tyrant-flycatchers. We then 152
compared plumage coloration for each pair of hypothetical models and mimics both 153
from the perspective of raptorial predators (using a VS vision model) and of the 154
study species themselves and smaller competitors (using an UVS vision model for 155
passerine birds) to evaluate the plausibility of deception of different observers. 156
Because raptors are likely the main diurnal predators of passerine birds (Acosta-157
Chaves et al., 2012; Amar et al., 2008; Gotmark, 1995; Thomson et al., 2010) 158
detecting them by sight (Mueller, 1975; Mueller, 1971; Slagsvold et al., 1995), the 159
hypothesis of social mimicry that species converge phenotypically to deceive 160
predators (Barnard 1979) predicts that species of flycatchers involved in the 161
mimicry complex should be very similar to each other or indistinguishable given 162
raptor vision in ecologically relevant plumage patches. On the other hand, 163
hypotheses positing that species evolve to deceive heterospecifics with which they 164
may compete for resources (Diamond 1982, Prum & Samuelson 2012, Prum 2014) 165
predict that tyrant flycatcher species involved in the mimicry complex should have 166
indistinguishable plumage coloration given their own passerine visual model. 167
168
METHODS 169
Study system 170
We studied Boat-billed Flycatcher (Megarynchus pitangua, mean body mass 73.5 171
g) and Great Kiskadee (Pitangus sulphuratus, 63.8 g) as hypothetical models, and 172
Lesser Kiskadee (Pitangus lictor, 25.5 g), White-bearded Flycatcher (Phelpsia 173
inornata, 29.4 g), Social Flycatcher (Myiozetetes similis, 28 g), and Rusty-margined 174
Flycatcher (Myiozetetes cayanensis, 25.9 g) as hypothetical mimics following Prum 175
(2014; mean body masses from Dunning, 2008). All these species are members of 176
the Tyrannidae family showing strikingly similar plumage patterns which we refer to 177
as “kiskadee-like”: black facial mask, white throat, bright yellow underparts, 178
brownish upperparts, and tail and wings with rufous edges (John Fitzpatrick et al., 179
2004; Hilty & Brown, 1986). They are all lowland species (500m-1700m) with wide 180
distribution ranges except for P. inornata, which is restricted to areas in the llanos 181
of Colombia and Venezuela (Fitzpatrick et al., 2004). The distribution ranges of 182
putative models and mimics overlap extensively and species share habitats in 183
mostly semi-open areas. Despite having very similar plumage patterns and 184
coloration to the human eye, the species have distinctive voices (Hilty & Brown, 185
1986). 186
187
Is plumage similarity product of convergent evolution? 188
To assess whether the similarity in phenotype among species of flycatchers is 189
product of convergent evolution or if it is a result of common ancestry, we 190
reconstructed ancestral states of a binary character (kiskadee-like or nonkiskadee-191
like) using stochastic mapping, a Bayesian approach in which character histories 192
are sampled from their posterior probability distribution (Huelsenbeck et al., 2003; 193
Ree, 2005; Revell, 2013b, 2013a). To conduct this analysis we used a subset of a 194
complete phylogeny of the Tyrannidae (Gomez-Bahamon, 2014), corresponding to 195
a clade defined by the most recent common ancestor of all study species except P. 196
inornata because no molecular data for this species are available. Using R 197
packages “ape” (Paradis et al., 2004, 2017) and “phytools” (Revell, 2012, 2017) we 198
generated 100 stochastically mapped trees using the “make.simmap” function 199
(Revell, 2017). Subsequently, we summarized them to estimate the number of 200
changes of each type and the proportion of time spent in each state, and using the 201
“densityMap” function we visualized the posterior probability of being in each state 202
across all the edges and nodes of the tree (Revell, 2013b). Although we were not 203
able to take spectrophotometric measurements of Conopias albovittatus we 204
included this species in the ancestral states reconstruction because it shares the 205
kiskadee-like plumage (Prum, 2014). 206
207
Quantifying plumage similarity 208
Reflectance measurements 209
We quantified plumage similarity between hypothetical models and mimics using 210
spectrophotometric data obtained from museum specimens deposited in the 211
Museo de Historia Natural de la Universidad de los Andes (ANDES), Instituto de 212
Ciencias Naturales de la Universidad Nacional (ICN), and Instituto de Investigación 213
de Recursos Biológicos Alexander von Humboldt (IAvH). We took reflectance 214
measurements using an Ocean Optics USB4000 spectrophotometer and a DH-215
2000 deuterium halogen light source coupled with a QP400-2-UV-VIS optic fiber 216
with a 400 µm diameter. We measured reflectance from eight patches: crown, 217
back, rump, throat, flank, upper breast, middle breast and belly (Figure 1). We 218
measured each patch three times per individual; the spectrometer was calibrated 219
using a white standard prior to measuring any new patch. We averaged the three 220
measurements per patch per individual and removed electrical noise using 221
functions implemented in the package “pavo” for R (Maia et al., 2013). 222
223
We quantified plumage coloration in six species belonging to the putative mimicry 224
complex described by Prum (2014); we were unable to include data for 225
Myiozetetes granadensis, Conopias parva and Conopias cinchoneti. We measured 226
spectra from 10 or 11 specimens per species except for P. inornata for which there 227
where only seven specimens available and P. sulphuratus for which 19 specimens 228
were measured. We used both female and male individuals and measured 229
specimens not older than 50 years (Armenta et al., 2008) for a total of 68 230
specimens and 1,632 spectra (Supplementary Table 1). 231
232
Statistical and perceptual analysis 233
To determine whether species putatively involved in the mimicry complex are 234
indeed indistinguishable from the perspectives of predators (raptors) or competitors 235
(passerines), one needs to address two separate questions: (1) Are hypothetical 236
models and mimics statistically distinct?; and (2) Are they perceptually different? 237
We addressed both questions following the approach described by Maia & White 238
(2017). We performed paired analysis between hypothetical models and mimics 239
comparing coloration of each plumage patch using the averaged and noise-free 240
spectra in the R package “pavo” based on the receptor-noise model (Vorobyev & 241
Osorio, 1998). This model assumes thresholds for discrimination are imposed by 242
receptor noise, which is dependent on the receptor type and its abundance in the 243
retina (Vorobyev & Osorio, 1998; Vorobyev et al., 2001). The model allows one to 244
estimate the distance between groups of points in a color space in units of “just 245
noticeable differences” or JNDs (Vorobyev et al., 2001). If when comparing two 246
colors the JND value is lower than 1, then those colors are predicted to be 247
indistinguishable given the visual model employed for analyses. 248
249
To determine whether hypothetical models and mimics are statistically different in 250
plumage coloration, we used permutation-based analyses of variance 251
(PERMANOVAs) using perceptual color distances in the R package “vegan” 252
(Oksanen et al., 2008). We used 999 permutations and recorded the pseudo-f, the 253
significance of the analysis (a=0.05), and the R2 (Maia & White, 2017). To evaluate 254
whether plumage patches showing statistical differences in reflectance are also 255
perceptually distinguishable we did a bootstrap analysis to calculate a mean 256
distance and a confidence interval in JNDs (Maia & White, 2017). If two colors are 257
statistically distinct and the bootstrapped confidence interval does not include the 258
threshold of 1 JND, then one can conclude that these colors are statistically distinct 259
and perceptually different given a visual model (Maia & White, 2017). 260
261
To assess statistical and perceptual differences from the perspective of raptors and 262
tyrant-flycatchers we performed the PERMANOVAs and the bootsraps assuming 263
two alternative visual models. First, we used the “avg.v” model implemented in 264
“pavo” which represents the standard violet-sensitive visual system; because there 265
is no information available for Accipitriformes, we used the Gallinula tenebrosa 266
(Rallidae) receptor densities -1:1.69:2.10:2.19- (Olsson et al., 2017). We then 267
used the “avg.uv” model representing the standard ultraviolet-sensitive visual 268
system and used the default receptor densities -1:2:2:4- which correspond to 269
Leiothrix lutea (Leothrichidae; Maia et al., 2017). We used a Weber fraction of 0.1 270
for both models (Maia et al., 2017). 271
272
273
RESULTS 274
Is plumage similarity among kiskadee-like flycatchers product of convergent 275
evolution? 276
Our analyses suggest there have been four independent evolutionary origins of the 277
kiskadee-like phenotype in: (1) Conopias albovittatus, (2) M. pitangua, (3) the 278
Myiozetetes clade and (4) the Pitangus clade (Figure 2). These four independent 279
origins of kiskadee-like plumage suggest that phenotypic similarity among putative 280
model and mimic species is product of convergence and not of common ancestry. 281
However, similarity due to common ancestry cannot be rejected in cases involving 282
closely related species (i.e Myiozetetes similis – M. cayanensis – M. granadensis 283
and Pitangus lictor - P. sulphuratus). 284
285
Can plumage similarity among flycatchers deceive putative competitors or 286
predators? 287
As predicted by various hypotheses involving social mimicry (Barnard, 1979; 288
Diamond, 1982; Prum, 2014; Prum & Samuelson, 2012), we found some pairs of 289
hypothetical model and mimic species to be indistinguishable from each other in 290
aspects of their plumage. Most hypothetical mimic species are perceptually 291
indistinguishable from hypothetical model M. pitangua in the coloration of the upper 292
breast, middle breast, belly and flanks (JND values ≤1; Figure 4 and 293
Supplementary Table 3) in spite of some being statistically different from each 294
other (Figure 4 and Supplementary Table 2). Additionally, all hypothetical mimics 295
are indistinguishable from both hypothetical models in plumage from the crown, 296
back and rump (JND values≤1; Figure 4, Figure 5A, Figure 6A and Supplementary 297
Table 3). Statistical and perceptual evaluation of the data were almost identical for 298
the UVS and VS visual models (Figure 4, Supplementary Table 2 and 299
Supplementary Table 3), indicating that both predators and competitors might be 300
deceived by the coloration of underpart plumage patches when considering M. 301
pitangua as hypothetical model or by upperpart patches when considering either 302
M. pitangua or P. sulphuratus as hypothetical models. Resemblance between M. 303
pitangua and hypothetical mimics exists because although there are differences in 304
brilliance of all the patches, the hue reflected by each patch is highly similar 305
between species (Figure 5C). Moreover, descriptive variables of the plumage (i.e 306
usml centroids, total and relative volumes, color span, hue disparity and saturation) 307
of each species vary between the two visual models (Supplementary Table 4). As 308
a graphical example of the variation, points occupied larger volume when being 309
evaluated using the UVS model than when being evaluated with the VS model 310
(Figure 5B). 311
312
Conversely, we found some pairs of hypothetical model and mimic species are 313
distinguishable in plumage, particularly in patches of the underparts. All 314
hypothetical mimics were perceptually distinguishable from hypothetical model M. 315
pitangua in plumage of the upper breast, middle breast, belly and flank patches 316
(JND values>1; Figure 3 and Figure 6A). Underpart patches were statistically 317
(Figure 4) and perceptually different in all comparisons. Additionally, we found two 318
species to be distinguishable from M. pitangua in some plumage patches: P. lictor 319
is distinguishable from M. pitangua in the middle breast and flank patches (lower 320
JND values 1.85 and 2.06 respectively; Supplementary Table 3) and M. 321
cayanensis was found to be distinguishable in the rump patch (lower JND value of 322
1.28; Supplementary Table 3). Color dissimilarity between P. sulphuratus and 323
hypothetical mimics is shown by the difference in the wavelengths reflected 324
between 450nm and 500nm in underpart patches (Figure 6C). Color dissimilarity in 325
underparts patches is also illustrated by variance in the values of the s centroid 326
when comparing hypothetical mimics and hypothetical models (Supplementary 327
Table 5). Statistical and perceptual evaluation of the data were almost identical 328
both for the UVS and VS models indicating that species are distinguishable by 329
models, smaller passerine species, and predatory raptors. Nevertheless, 330
descriptive variables of the plumage of each species varied when using UVS and 331
VS models (Supplementary Table 4), illustrated by points occupying a larger 332
volume when being evaluated using the UVS model than when being evaluated 333
with the VS model (Figure 6B). 334
335
336
DISCUSSION 337
Although plumage convergence is widespread (Barnard, 1979, 1982; Cody & 338
Brown, 1970; Davies & Welbergen, 2008; Laiolo, 2017; Leighton et al., 2018; 339
Moynihan, 1968; Prum, 2014; Prum & Samuelson, 2016, 2012; Stoddard, 2012), 340
few studies have assessed the mechanisms underlying this phenomenon. For 341
example, convergence has been documented in previous studies of birds which 342
may engage in mimicry including toucans (Weckstein, 2005), friarbirds and orioles 343
(Jønsson et al., 2016), and woodpeckers (Leighton et al., 2018; Miller et al., 2018) 344
but the extent to which alternative hypotheses involving mimicry may account for 345
convergence is unknown. A first step to examine the plausibility of alternative 346
hypotheses posed to account for mimicry is to determine whether two or more 347
sympatric and phenotypically similar species indeed acquired their resemblance 348
due to convergence and not as a consequence of common ancestry. We found 349
that phenotypic similarity among Neotropical flycatcher species with kiskadee-like 350
plumage pattern is indeed a product of convergence among hypothetical mimics in 351
the genera Myiozetetes, Pitangus and Phelpsia, and hypothetical models in 352
Megarynchus and Pitangus. 353
354
The hypothesis that mimicry in birds arises as an antipredatory strategy (Barnard 355
1979) predicts that plumages should be indistinguishable to predators given their 356
visual system. Moreover, mimicry should be more precise in plumage patches 357
used by predators as cues to select prey (Barnard, 1979). The main predators of 358
adult songbirds, including tyrant flycatchers, are likely diurnal raptors (Amar et al., 359
2008; Acosta-Chaves et al., 2012; Motta-Junior, 2007; Selas, 1993), which often 360
observe prey from long distances while perched on treetops (Clark & Wheeler, 361
2001) and may choose odd individuals relative to their background (Mueller, 1971, 362
1975). Consequently, similarity in upperpart coloration in species that forage 363
together or use different strata of the same trees may create a sense of 364
homogeneity and thereby be adaptive to avoid attacks from predators approaching 365
from above. In agreement with this hypothesis, our analyses of kiskadee-like 366
flycatchers revealed that all hypothetical mimics are indistinguishable from 367
hypothetical models in the coloration of upperpart plumage patches, which would 368
arguably be the most relevant ones considering the perspective of predatory 369
diurnal raptors perched on treetops. 370
371
Wallace (1863, 1869) and later Diamond (1982) were amazed by the striking 372
similarity in plumage between orioles (genus Oriolus, family Oriolidae) and 373
friarbirds (genus Philemon, family Meliphagidae). Wallace first claimed such 374
similarity was a case of visual mimicry, but no study on the subject was done until 375
Diamond (1982) posited that visual mimicry may serve to escape attack from larger 376
model species or to deceive smaller species and scare them off only by 377
appearance. Prum & Samuelson (2012) and Prum (2014) further expanded on the 378
first idea by positing the ISDM hypothesis and outlining its predictions. A recent 379
analysis assessing ISDM on orioles and friarbirds using phylogenetic methods 380
suggested that orioles indeed appear to mimic larger-bodied friarbirds (Jønsson et 381
al., 2016), but there is no information about the species being deceived in this 382
system. In principle, ISDM may also apply to kiskadee-like flycatchers because 383
existing data support the prediction that hypothetical model species are larger in 384
body mass (i.e. at least 30g heavier) than hypothetical mimic species. The 385
additional prediction that models are socially dominant over mimics has not been 386
tested quantitatively, but several observations exist of both hypothetical model 387
species scaring off hypothetical mimics from foraging grounds (personal 388
communications with other ornithologists). Also, we found that shared phenotypic 389
similarities between model and mimic species are not product of common ancestry: 390
our ancestral state character reconstructions revealed that because the kiskadee-391
like phenotype has evolved at least four times independently it is product of 392
convergence. 393
394
A critical additional prediction of the ISDM hypothesis is that visual deception 395
based on covergent coloration should be physiologically plausible at ecologically 396
relevant visual distances between individuals (Prum, 2014). We found partial 397
support for this prediction in kiskadee-like tyrant flycatchers. On one hand, 398
because all hypothetical mimics were perceptually distinguishable from 399
hypothetical model P. sulphuratus in the coloration of the upper breast, middle 400
breast, abdomen and flank patches using the UVS model, and considering that 401
underpart patches are visually relevant when two species engage physically in 402
interference competition (Schoener, 1983), our analyses reject the proposition that 403
visual deception is physiologically possible when having P. sulphuratus as 404
hypothetical model. This result is consistent with previous work in other birds 405
showing that despite striking similarity to the human eye, putatively mimic Downy 406
Woodpeckers (Picoides pubescens) do not experience reduced aggression from 407
hypothetical model Hairy Woodpeckers (Picoides villosus), implying lack of 408
deception (Leighton et al., 2018). Because Downy Woodpeckers were more 409
dominant over other bird species than expected based on their body size, 410
convergence in plumage with Hairy Woodpeckers may instead have evolved to 411
deceive smaller third-party species (Diamond, 1982; Leighton et al., 2018), a 412
hypothesis to be tested in kiskadee-like flycathers resembiing P. sulphuratus. 413
414
On the other hand, we found that most hypothetical mimics are perceptually 415
indistinguishable from M. pitangua in underpart plumage patches. Perceptual 416
similarity given the UVS model indicates that M. pitangua might be deceived by 417
hypothetical mimics, misidentify them as conspecifics, and thus split resources with 418
them owing to reduced agression. Alternatively, other passerines might be 419
deceived by hypothetical mimics, misidentify them as M. pitangua individuals, and 420
therefore withdraw from any interaction which may potentially result in attack. 421
Consequently, our results are consistent with mimicry hypotheses that imply 422
deception of either putative models or smaller passerine competitors (Diamond, 423
1982; Prum, 2014; Prum & Samuelson, 2012, 2016) when considering M. pitangua 424
as the putative model. We are unable to fully support either hypotheses given our 425
results but we agree with Leighton et al. (2018) in that because individuals are 426
expected to be very good at identifying conspecifics given its importance for 427
competition and successful breeding, visual deception of hypothetical models 428
seems unlikely. Alternatively, because selective pressures to identify individuals 429
which are not predators, prey or strong competitors are likely reduced, visual 430
deception of species that are neither hypothetical mimics or models may be more 431
likely (Diamond, 1982; Leighton et al., 2018). 432
433
Ours is the first study to assess the plausibility of mimicry hypotheses in birds 434
using spectrophotometric measurements of plumage, and evaluating the data with 435
statistical and perceptual analysis (Maia & White, 2017) given two avian visual 436
models. Additional work is required to further evaluate hypotheses accounting for 437
plumage convergence. For instance, although our study species overlap in 438
geographic range, diet and foraging strategies (Fitzpatrick, 1980; Fitzpatrick, 1981; 439
Fitzpatrick et al., 2004), very little is known about interactions between them; the 440
extent to which hypothetical models are indeed deceived by hypothetical mimics 441
should be evaluated through behavioral observations and experiments. Likewise, 442
field studies are required to assess whether predators such as raptors are indeed 443
deceived by putative models and mimics to escape predation. In addition, there is 444
no knowledge of how perception of color may vary with distance between 445
individuals or of how to account for distances over which individuals interact in the 446
field when analyzing spectrophotometric data. Hence, we do not know precisely 447
how likely deception is at ecologically relevant distances, an important condition for 448
ISDM (Prum, 2014). For example, while some hypothetical models may be 449
distinguishable by hypothetical mimcs upon inspection at close distances, 450
hypothetical mimic species may be able to deceive hypothetical models from 451
greater distances (Leighton et al., 2018). Finally, we accounted for passerines’ and 452
raptors’ visual systems using available standard UVS and VS models however, 453
specific visual models of putative models, mimics and third-party receptors are 454
necessary for a more accurate assessment of social mimicry hypotheses. 455
456
In conclusion, perceptual similarity of the crown, back and rump patches among 457
species is consistent with the hypothesis that predation by visually oriented 458
predators approaching their prey from above may have favored convergence in 459
plumage in kiskadee-like tyrant flycatchers (Barnard, 1979). Perceptual similarity 460
suggests that deception involved in competitive interactions with M. pitangua, but 461
not with P. sulphuratus, may also have favored convergence (Diamond, 1982; 462
Prum, 2014; Prum & Samuelson, 2012, 2016). Future studies should focus on 463
gathering behavioral data to characterize competitive and predator-prey 464
interactions among species involved in social mimicry. Moreover, assessing how 465
other factors like climate, habitat and development shape the evolution of plumage 466
would allow for a comprehensive understanding of the mechanisms underlying 467
convergence in plumage. 468
469
Acknowledgments: 470
We thank Museo de Historia Natural de la Universidad de los Andes (ANDES), 471
Instituto de Ciencias Naturales de la Universidad Nacional (ICN), and Instituto de 472
Investigación de Recursos Biológicos Alexander von Humboldt (IAvH) for 473
permitting us take spectrophotometric measurements of museum specimens. 474
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Figure 1. Plumage patches measured to characterize coloration and compare
plumage among species of “kiskadee-like” flycatchers.
Figure 2. Stochastic mapping of the binary discrete character kiskadee-like shown in yellow and non-kiskadee like shown
in brown indicating that plumage similarity reflects convergence due to repeated evolution of the same plumage pattern.
Asterisks point edges corresponding to kiskadee-like clades or species. Pictures show examples of the diversity of
phenotypes in the clade including the species studied. Photo credits: Nick Bayly and Laura Céspedes.
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Figure 3. Overview of the results of perceptual analysis considering upper breast,
lower breast, belly and flank plumage patches. While all four hypothetical models
are distinguishable from P. sulphuratus, three out of four species are
indistinguishable from M. pitangua.
Figure 4. Statistical and perceptual distinction of patches using the UVS and VS model. Patches that are statistically
different are shown in yellow (a≥0.05 for the PERMANOVA). Patches that are perceptually different (JNDS>1) are shown
with an asterisk.
Patch/ Species
Upper breast
Lower breast Belly Crown Back Flank Throat Rump Upper
breastLower breast Belly Crown Back Flank Throat Rump
M. pitangua/ M. cayanensis * *M. pitangua/
M. similisM. pitangua/ P. inornata
M. pitangua/ P. lictor * * * *
P. sulphuratus/ M. cayanensis * * * * * * * *P. sulphuratus/
M. similis * * * * * * * *P. sulphuratus/
P. inornata * * * * * * * * P. sulphuratus/
P. lictor * * * * * * * *
UVS VS
Figure 5. A pair of hypothetical model and mimic species that are
indistinguishable. A) Comparison of the chromatic contrast of the centroids for
each patch using the UVS (yellow) and the VS (black) models. B) Distribution of
the color volume of each species in the tetrahedral colorspace using UVS and VS
models. C) Comparison of the reflectance curves of all patches of both species.
A
B C
Figure 6. A pair of hypothetical model and mimic species that are distinguishable.
A) Comparison of the chromatic contrast of the centroids for each patch using the
UVS (yellow) and the VS (black) models. B) Distribution of the color volume of
each species in the tetrahedral colorspace using UVS and VS models. C)
Comparison of the reflectance curves of all patches of both species.
A
B C
Supplementary Figure 1. Comparison between M. pitangua and M. cayanensis, a
pair of hypothetical model and mimic that are indistinguishable except for the rump
patch A) Comparison of the chromatic contrast of the centroids for each patch
using the UVS (yellow) and the VS (black) models. B) Distribution of the color
volume of each species in the tetrahedral colorspace using UVS and VS models.
C) Comparison of the reflectance curves of all patches of both species.
A
B C
Supplementary Figure 2. Comparison between M. pitangua and P. lictor, a pair of
hypothetical model and mimic that are distinguishable given middle breast and
flank patches A) Comparison of the chromatic contrast of the centroids for each
patch using the UVS (yellow) and the VS (black) models. B) Distribution of the
color volume of each species in the tetrahedral colorspace using UVS and VS
models. C) Comparison of the reflectance curves of all patches of both species.
A
B C
Supplementary Table 1. Complete specimen information.
Species Museum Cataloguenumber Yearcollected Mass(g) Sex1 Pitangussulphuratus IAvH 4609 1984 58 Female2 Pitangussulphuratus IAvH 6198 1986 N Male3 Pitangussulphuratus IAvH 5996 1975 N N4 Pitangussulphuratus IAvH 1785 1976 53,9 Female5 Pitangussulphuratus IAvH 1877 1976 53,5 Male6 Pitangussulphuratus IAvH 4608 1984 64 Male7 Pitangussulphuratus IAvH 14281 2007 49 Female8 Pitangussulphuratus IAvH 2916 N N N9 Pitangussulphuratus IAvH 2888 1979 N N10 Pitangussulphuratus IAvH 6197 1986 N Female11 Pitangussulphuratus IAvH 6010 1986 60 Male12 Pitangussulphuratus IAvH 6009 1987 51 Female13 Pitangussulphuratus IAvH 7514 1994 45,9 Male14 Pitangussulphuratus IAvH 2189 1975 N Female15 Pitangussulphuratus IAvH 0772 1969 53,7 N16 Pitangussulphuratus IAvH 0330 1970 N Male17 Pitangussulphuratus IAvH 12916 2004 58 Female18 Pitangussulphuratus IAvH 14759 2008 60,6 Male19 Pitangussulphuratus ANDES 00079 1974 N N20 Pitanguslictor IAvH 5068 1977 24,4 Male21 Pitanguslictor IAvH 2841 1979 N Female22 Pitanguslictor IAvH 5067 1977 22 Female23 Pitanguslictor IAvH 5066 1977 23,6 Male24 Pitanguslictor IAvH 1816 1976 19,1 Female25 Pitanguslictor IAvH 1856 1976 23,8 Male26 Pitanguslictor ICN 5315 1974 22,548 Male27 Pitanguslictor ICN 30825 1989 N Male28 Pitanguslictor ICN 31383 1990 N Female29 Pitanguslictor ICN 38414 2011 25 Male30 Myiozetetessimilis IAvH 1738 1977 27 Male31 Myiozetetessimilis IAvH 5993 1975 N N32 Myiozetetessimilis ICN 39344 2015 27 Male33 Myiozetetessimilis ICN 39359 2011 28,9 Female34 Myiozetetessimilis ICN 34869 2004 26 Female35 Myiozetetessimilis ICN 2552 1977 24,672 Male36 Myiozetetessimilis ICN 38415 2011 25,5 Male37 Myiozetetessimilis ICN 32435 1978 N Female38 Myiozetetessimilis ICN 7094 1960 N Male39 Myiozetetessimilis ICN 28523 1984 23,5 Female40 Myiozetetescayanensis IAvH 1114 1975 N Male41 Myiozetetescayanensis IAvH 4620 1984 28 Male42 Myiozetetescayanensis IAvH 4621 1984 27 Female43 Myiozetetescayanensis IAvH 11483 2000 24 Male44 Myiozetetescayanensis IAvH 6047 N N N45 Myiozetetescayanensis IAvH 5037 1977 28 Male46 Myiozetetescayanensis IAvH 3687 1976 26,4 Male47 Myiozetetescayanensis IAvH 5117 1976 28,9 Female48 Myiozetetescayanensis IAvH 5295 1974 N Male49 Myiozetetescayanensis IAvH 13754 2004 24 Male50 Myiozetetescayanensis IAvH 13755 2004 22 Female51 Phelpsiainornata IAvH 14737 2008 25,5 Female52 Phelpsiainornata ICN 31033 1991 30 Male53 Phelpsiainornata ICN 31003 1991 27 Female54 Phelpsiainornata ICN 31032 1991 27 Male55 Phelpsiainornata ICN 31026 1991 31 Female56 Phelpsiainornata ICN 38372 2011 22,5 Female57 Phelpsiainornata ICN 31040 1991 23 Female58 Megarhynchuspitangua IAvH 13685 2004 56 Male59 Megarhynchuspitangua IAvH 1855 1975 70,1 Male60 Megarhynchuspitangua IAvH 15109 2009 51 Male61 Megarhynchuspitangua IAvH 15919 2017 69 Male62 Megarhynchuspitangua ANDES 0192 1972 N Male63 Megarhynchuspitangua ANDES 00076 1975 N N64 Megarhynchuspitangua ICN 38860 2013 68 Female65 Megarhynchuspitangua ICN 34202 2002 56,8 Male66 Megarhynchuspitangua ICN 35274 2005 62 Female67 Megarhynchuspitangua ICN 38418 2011 54,4 Female68 Megarhynchuspitangua ICN 31589 1991 48,6 Female
Supplementary Table 2. Pseudo-f, R2 and significance (a=0.05) for the PERMANOVA using the UVS and VS models.
Patches that are statistically different are bolded and highlighted in gray.
Patch/ Species
Upper breast
Lower breast Belly Crown Back Flank Throat Rump Upper
breastLower breast Belly Crown Back Flank Throat Rump
M. pitangua/ M. cayanensis
0.4676 0.02402 (0.665)
1.8493 0.09317 (0.137)
1.3606 0.07837
0.277
6.0436 0.25136 (0.012)
6.2252 0.25697 (0.004)
1.2018 0.07418 (0.268)
0.71904 0.03841 (0.545)
13.995 0.43742 (0.001)
0.359 0.01854 (0.726)
2.0894 0.10401 (0.126)
1.3721 0.07898 (0.25)
5.5125 0.23445 (0.021)
6.5988 0.26826 (0.007)
1.5874 0.0957 (0.214)
0.1473 0.00812 (0.892)
16.351 0.476
(0.001)
M. pitangua/ M. similis
1.1536 0.05724 (0.348)
1.6763 0.0852 (0.191)
2.131 0.1139 (0.112)
4.2569 0.19126 (0.02)
2.303 0.11931 (0.103)
1.2509 0.06177 (0.288)
1.7602 0.09911 (0.171)
1.4301 0.0736 (0.253)
1.4012 0.06868 (0.233)
1.535 0.07858 (0.193)
2.6618 0.13538 (0.065)
3.4388 0.1604 (0.048)
2.4883 0.12768 (0.106)
1.0049 0.05023 (0.36)
1.7724 0.0973 (0.16)
2.311 0.11378 (0.093)
M. pitangua/ P. inornata
0.50355 0.03051 (0.627)
5.3743 0.26378 (0.011)
1.7371 0.11038 (0.13)
0.69618 0.4435 (0.62)
1.8724 0.11097 (0.157)
2.4138 0.13109 (0.103)
1.5899 0.09584 (0.203)
5.5515 0.25759 (0.002)
0.32459 0.01988 (0.723)
5.6185 0.2725 (0.021)
2.1776 0.12461 (0.053)
0.65478 0.04183 (0.659)
2.0913 0.12236 (0.131)
2.3717 0.12909 (0.096)
1.2396 0.07633 (0.252)
6.878 0.30064 (0.001)
M. pitangua/ P. lictor
0.98412 0.04925 (0.359)
13.047 0.42024 (0.001)
1.5509 0.07932 (0.188)
0.69368 0.03711 (0.544)
7.8419 0.30346 (0.001)
12.735 0.40129 (0.001)
2.2121 0-11514 (0.115)
6.21 0.24633 (0.001)
0.99554 0.04979 (0.354)
12.756 0.41475 (0.001)
4.0197 0.18255 (0.015)
0.69357 0.0371 (0.525)
7.6763 0.29897 (0.004)
12.4 0.39491 (0.002)
1.3432 0.07323 (0.264)
6.7053 0.26085 (0.001)
P. sulphuratus/ M. cayanensis
24.051 0.47111 (0.001)
18.568 0.41662 (0.001)
24.434 0.52621 (0.001)
13.104 0.3351 (0.002)
1.1484 0.0423 (0.343)
16.196 0.42402 (0.001)
1.0884 0.04018 (0.367)
1.2281 0.04683 (0.284)
19.848 0.42367 (0.001)
17.059 0.39618 (0.001)
20.645 0.48411 (0.001)
11.653 0.30948 (0.002)
1.43 0.05213 (0.243)
15.764 0.41743 (0.002)
1.3302 0.04867 (0.278)
1.4213 0.05379 (0.253)
P. sulphuratus/ M. similis
49.262 0.64596 (0.001)
35.999 0.58064 (0.001)
21.038 0.47772 (0.001)
9.651 0.27071 (0.002)
1.0894 0.04176
0.307
29.831 0.53431 (0.001)
5.9367 0.19831 (0.003)
4.3567 0.1484 (0.016)
50.007 0.64938 (0.001)
37.753 0.59218 (0.001)
22.32 0.4925 (0.001)
8.185 0.23943 (0.004)
1.1592 0.04431 (0.307)
33.882 0.56581 (0.001)
5.9003 0.19733 (0.007)
4.4667 0.15159 (0.014)
P. sulphuratus/ P. inornata
26.683 0.52647 (0.001)
49.66 0.68346 (0.001)
17.321 0.46411 (0.001)
1.1874 0.04909 (0.294)
0.17224 0.00743 (0.884)
34.964 0.6032 (0.001)
0.68955 0.02911 (0.549)
1.0092 0.04203 (0.373)
28.594 0.54367 (0.001)
46.531 0.66921 (0.001)
18.545 0.48113 (0.001)
1.094 0.0454 (0.329)
0.24154 0.01039 (0.829)
40.732 0.63911 (0.001)
0.87835 0.03678 (0.439)
1.0931 0.04537 (0.34)
P. sulphuratus/ P. lictor
33.653 9.55485 (0.001)
92.421 0.78045 (0.001)
57.321 0.70487 (0.001)
0.72764 0.02722 (0.449)
1.5972 0.05788 (0.186)
96.641 0.788
(0.001)
0.33579 0.01325 (0.732)
1.2281 0.04511 (0.299)
33.905 0.55668 (0.001)
86.933 0.76978 (0.001)
63.237 0.72489 (0.001)
0.5704 0.02147 (0.533)
1.8885 0.06772 (0.154)
101.21 0.79562 (0.001)
0.15652 0.00622 (0.883)
1.0949 0.04041 (0.339)
UVS VS
Supplementary Table 3. Upper, mean and lower values of JND resulting of the bootstrap analysis using the UVS and VS
models. Patches that are perceptually different are bolded and highlighted in gray
Patch/ Species
Upper breast
Lower breast
Belly Crown Back Flank Throat RumpUpper breast
Lower breast
Belly Crown Back Flank Throat Rump
M. pitangua/ M. cayanensis
1.84782 0.68578 0.25508
2.77256 1.33060 0.32700
1.56837 0.51545 0.12514
2.13576 1.31581 0.44122
2.73130 1.74257 0.86145
3.50514 1.42195 0.21538
0.66411 0.18632 0.05894
2.89343 2.04907 1.28297
1.93170 0.73610 0.39510
3.07365 1.50165 0.46793
1.63226 0.70648 0.25162
2.04874 1.27193 0.46927
2.68273 1.76733 0.80649
4.36253 1.83271 0.33683
0.61005 0.08608 0.05094
2.93722 2.13473 1.30281
M. pitangua/ M. similis
1.93882 0.60853 0.21472
2.33756 1.14127 0.23330
1.99843 0.83440 0.27023
1.50689 0.91157 0.46097
1.85784 0.93243 0.28598
2.44313 1.08735 0.33553
1.05471 0.47050 0.18538
1.34028 0.714910 0.29431
1.89696 0.71750 0.32759
2.35033 1.15275 0.33534
2.51170 1.18425 0.42560
1.29852 0.75663 0.39680
1.76760 0.93755 0.28370
2.39822 0.96852 0.38626
1.07435 0.44536 0.15348
1.41686 0.76207 0.27497
M. pitangua/ P. inornata
1.97583 0.71140 0.31527
3.21930 2.03920 1.00077
3.68630 1.09585 0.44695
1.97085 0.42465 0.13360
2.18689 1.02144 0.23618
2.68352 1.36010 0.50710
0.73109 0.46270 0.32513
2.57742 1.73330 0.94297
1.99593 0.49674 0.34038
3.28193 2.09526 0.99656
4.27167 1.65670 0.84323
1.97986 0.44594 0.12552
2.29990 1.03450 0.23350
2.60943 1.38725 0.83435
0.73396 0.34375 0.15773
2.70387 1.81234 0.99737
M. pitangua/ P. lictor
2.91661 1.15470 0.35040
4.16115 2.95553 1.86160
1.47045 0.78637 0.43842
1.39716 0.19251 0.10320
2.60196 1.76965 0.89673
4.70175 3.31084 2.05997
1.18237 0.71101 0.54635
2.62467 1.73456 0.94500
3.01910 1.36010 0.81078
4.27714 3.01592 1.88757
1.86265 1.32183 0.96910
1.45659 0.16680 0.09489
2.60761 1.73697 0.87897
4.83556 3.41051 2.05276
1.01570 0.50566 0.37102
2.76860 1.79276 1.02133
P. sulphuratus/ M. cayanensis
4.17953 3.19090 2.27200
4.61246 3.43020 2.50836
4.86849 3.87286 3.00945
2.59696 1.81950 0.90270
2.18092 1.17552 0.56565
5.83154 4.04628 2.35257
0.98754 0.55568 0.29010
1.50774 0.69169 0.50565
4.24660 3.24158 2.20196
4.87178 3.53406 2.48152
5.00820 3.99124 3.06008
2.63886 1.77925 0.90430
2.38593 1.29107 0.57346
6.07556 4.29448 2.50053
0.97195 0.52192 0.24353
1.60011 0.74035 0.54342
P. sulphuratus/ M. similis
5.13938 4.23297 3.42743
4.65684 3.84603 3.07083
4.76579 3.70523 2.85261
1.95003 1.36178 0.81214
1.52995 0.94237 0.76610
4.95356 3.93950 2.97652
1.51430 1.06415 0.74402
2.41040 1.53307 0.95995
5.21327 4.38335 3.60477
4.85727 4.01543 3.41980
4.95482 3.95028 3.38276
1.82078 1.18211 0.57281
1.68346 0.99025 0.82523
5.18412 4.19673 3.44696
1.50028 0.93954 0.53602
2.28780 1.48238 1.04066
P. sulphuratus/ P. inornata
4.77582 3.73910 2.80516
5.47310 4.63119 3.90392
5.00762 3.45081 2.09976
2.44194 0.92861 0.18933
1.64297 0.67550 0.51740
5.06601 4.20333 3.43885
0.56807 0.15761 0.08126
1.59253 0.81647 0.74274
5.11202 4.08020 3.21150
5.62168 4.82160 4.18121
5.53453 4.02480 3.17691
2.64407 0.96210 0.21586
1.86924 0.78144 0.60124
5.29528 4.60677 4.04456
0.51196 0.21962 0.14521
1.58372 0.90471 0.84920
P. sulphuratus/ P. lictor
6.41404 4.81370 3.45111
6.50857 5.61481 4.79610
5.32662 4.58320 3.83827
1.82199 0.69452 0.15865
2.14781 1.20597 0.56369
7.06043 6.09806 5.12313
0.91613 0.11853 0.05180
1.60850 0.84235 0.72661
6.55423 5.01182 3.67403
6.62168 5.77015 4.97097
5.76014 5.03370 4.44598
1.93793 0.68216 0.09781
2.27481 1.34426 0.69570
7.42043 6.50724 5.63451
0.73439 0.01071 0.03557
1.68630 0.91171 0.82904
UVS VS
Supplementary Table 4. Comparison of descriptive variables for all species using the UVS and VS models.
M.pitangua M.cayanensis M.similis P.inornata P.lictor P.sulphuratus M.pitangua M.cayanensis M.similis P.inornata P.lictor P.sulphuratusTotalvolume 0.00058 0.00084 0.00042 0.00056 0.00080 0.00109 0.00026 0.00039 0.00019 0.00024 0.00035 0.00053
Relativevolume 0.00266 0.00393 0.00194 0.00259 0.00367 0.00503 0.00125 0.00179 0.00088 0.00112 0.00166 0.00246MeanColorSpan 0.12838 0.12560 0.11621 0.12980 0.13245 0.12168 0.12157 0.11887 0.11317 0.12414 0.13019 0.10721
VarianceColorSpan 0.00724 0.00620 0.00625 0.00727 0.00808 0.00579 0.00714 0.00614 0.00657 0.00742 0.00857 0.00468MeanHueDisparity 0.47437 0.40336 0.31162 0.48567 0.56387 0.68113 0.32513 0.32007 0.23890 0.36101 0.49453 0.58716
VarianceHueDisparity 0.17914 0.11101 0.06905 0.20825 0.38809 0.41527 0.09420 0.06902 0.09217 0.12719 0.39639 0.37552MeanSaturation 0.46350 0.47155 0.49650 0.48308 0.52034 0.38563 0.42362 0.46456 0.44662 0.43672 0.46616 0.42695
MaximumSaturation 0.79879 0.82006 0.82484 0.80652 0.84461 0.74497 0.77300 0.82104 0.78692 0.74963 0.80286 0.78610
VSUVS
Supplementary Table 5. Comparison of centroid values of underpart patches for all species using the UVS and VS
models.
M.pitangua M.cayanensis M.similis P.inornata P.lictor P.sulphuratus M.pitangua M.cayanensis M.similis P.inornata P.lictor P.sulphuratusucentroid 0.14033 0.13016 0.13410 0.12556 0.13642 0.12876 0.08573 0.08090 0.08397 0.08570 0.08654 0.09722scentroid 0.07265 0.07783 0.06695 0.07238 0.06354 0.12285 0.11865 0.12706 0.10920 0.11294 0.10250 0.17621mcentroid 0.37774 0.37909 0.37540 0.37484 0.37166 0.36446 0.38203 0.37936 0.37941 0.37488 0.37705 0.35408lcentroid 0.40926 0.41291 0.42352 0.42722 0.42836 0.38393 0.41356 0.41269 0.42740 0.42644 0.43391 0.37253
M.pitangua M.cayanensis M.similis P.inornata P.lictor P.sulphuratus M.pitangua M.cayanensis M.similis P.inornata P.lictor P.sulphuratusucentroid 0.13994 0.11624 0.12870 0.12137 0.12151 0.11452 0.08996 0.07394 0.08335 0.07633 0.07318 0.08572scentroid 0.08001 0.07367 0.06924 0.06119 0.05308 0.11946 0.12644 0.12139 0.11219 0.10252 0.09210 0.17597mcentroid 0.37574 0.38461 0.37979 0.38105 0.38387 0.37097 0.37762 0.38240 0.38115 0.38316 0.38837 0.35779lcentroid 0.40429 0.42546 0.42226 0.43635 0.44155 0.39504 0.40596 0.42225 0.42329 0.43799 0.44633 0.38052
M.pitangua M.cayanensis M.similis P.inornata P.lictor P.sulphuratus M.pitangua M.cayanensis M.similis P.inornata P.lictor P.sulphuratusucentroid 0.10875 0.10101 0.12559 0.12893 0.12142 0.10940 0.06734 0.06270 0.08140 0.08910 0.07739 0.07915scentroid 0.06419 0.06632 0.06883 0.07521 0.05991 0.11538 0.10901 0.11497 0.11209 0.11355 0.09860 0.17425mcentroid 0.39160 0.39476 0.38168 0.36843 0.37891 0.37466 0.39020 0.39008 0.38240 0.36952 0.38166 0.36110lcentroid 0.43544 0.43789 0.42388 0.42741 0.43972 0.40056 0.43342 0.43223 0.42409 0.42781 0.44235 0.38548
M.pitangua M.cayanensis M.similis P.inornata P.lictor P.sulphuratus M.pitangua M.cayanensis M.similis P.inornata P.lictor P.sulphuratusucentroid 0.14215 0.12342 0.14417 0.13942 0.12169 0.13744 0.09236 0.07307 0.08846 0.08780 0.07200 0.09371scentroid 0.08074 0.06985 0.06887 0.06597 0.05082 0.11966 0.12626 0.11822 0.11323 0.10765 0.08841 0.17975mcentroid 0.37521 0.38475 0.37650 0.37462 0.38166 0.3662 0.37743 0.38590 0.38211 0.37958 0.38745 0.35825lcentroid 0.40188 0.42196 0.41045 0.41999 0.44581 0.37670 0.40394 0.42279 0.41618 0.42498 0.45211 0.36826
UVS VS
UVS VSMiddlebreast
UpperBreast
UVS VS
UVS VS
Flank
Belly