Sneaky copulations by subordinate males suggest direct fitness benefits from male–male associations in spotted bowerbirds (Ptilonorhynchus maculatus)

Male spotted bowerbirds (Ptilonorhynchus maculatus) build and defend a structure of sticks and straw—the bower—decorated with colourful objects to attract mates during the breeding season. Specific non-territorial, subordinate males are tolerated by resident males at bowers over multiple breeding seasons. Prior research showed that these male–male associations exhibit attributes of coalitionary behaviour and that subordinate males gain delayed benefits from associating with bower owners, namely future bower inheritance. Yet, it remained unclear whether subordinate males may additionally gain direct fitness benefits from attending established bowers. Here, we report on four separate instances of sneaky copulations (or attempts of copulating) by subordinate males at resident males' bowers. Multiple non-resident males disrupted the ongoing copulations between the bower owner and a receptive female, and these events were followed by violent aggressive interactions. These observations shed new light on same-sex social dynamics in spotted bowerbirds and support the hypothesis that subordinate males are sexually mature individuals that occasionally obtain access to females while attending established bowers. We discuss these findings in light of the literature on male courtship coalitions and agonistic behaviour in bowerbirds, and highlight further aspects of subordinate behaviour that require empirical investigation.     

Vocal mimicry in spotted bowerbirds is associated with an alarming context

Although the presence of vocal mimicry in songbirds is well documented, the function of such impressive copying is poorly understood. One explanation for mimicry in species that predominantly mimic alarm calls and predator vocal isations is that these birds use mimicry to confuse or deter potential threats or intruders, so these vocalisations should therefore be produced when the mimic is alarmed and be uncommon in other contexts. Male bowerbirds construct bowers to display to females and anecdotal reports from the Ptilonorhynchus genus suggest that males mimic alarm sounds when disturbed at their bowers. We quantified and compared the rate of mimicry during disturbance to the bower by a human and in naturally occurring social contexts in a population of spotted bowerbirds Ptilonorhynchus maculatus. Male bowerbirds produced mimicry more than thirty times more frequently in response to bower disturbance than they did in any other context. Neither conspecifics nor heterospecifics were attracted to the bower area by mimicry. These data are consistent with the hypothesis that the production of mimicry is associated with a response to an alarming situation. Additionally, the predominance of alarm mimicry by spotted bowerbirds raises the possibility that the birds learn these sounds when they experience alarming situations and they reproduce them in subsequent alarming situations.     

Cytochrome b gene sequence divergence of seven sisorid species of catfish genus <Emphasis Type="Italic">Glyptothorax</Emphasis> (siluriformes,sisoridae) from India

Samples of seven Sisorid catfish species of the genus Glyptothorax (G. garhwali, G. dakpathari, G. brevipinnis, G. ngapang, G. granulus, G. ventrolineatus, and G. davissinghi) were collected from the Himalayan region and the Western Ghats of India. They were analyzed for the mitochondrial cytochrome b gene (Cyt b). Out of 1152 nucleotide positions analyzed, 269 (23.3%) were found to be variable and 235 (20.3%) were parsimoniously informative. The sequences showed 111 (9.6%) fourfold degenerate sites. The overall transition/transversion bias was R = 3.457. The average proportion of base substitutions measured as P-distance for all sequences of seven Glyptothorax species and other five species comprising four comparison groups was intraspecies, P = 0.17 ± 0.05%, intragenus, P = 10.75 ± 0.48%, intrafamily, P = 20.07 ± 1.43%, and intraorder, P = 21.10 ± 0.45%. Within the Glyptothorax genus maximum divergence was obtained among G. brevipinnis sequences, whereas the least divergence was obtained within G. davissinghi. The phylogenetic trees for 193 and 47 sequences of Sisorid catfishes together were developed using the Cyt b gene and four different analytical approaches: Bayesian (BA), neighbour-joining (NJ), maximum parsimony (MP), and maximum likelihood (ML). The analysis revealed a monophyletic origin for the all investigated representatives of the genus Glyptothorax (99, 100, 99, and 73% support level in our BA, NJ, MP, and ML analyses respectively) and with some reservations for Sisoridae, which is the principal family investigated. The monophyletic origin of the two subfamilies of Sisorid catfish defined in the literature was partly also supported by molecular phylogenetic data.     

Molecular phylogeny of Old WorldTrifolium (Fabaceae), based on plastid and nuclear markers

Phylogenies of Old WorldTrifolium species were constructed using nucleotide sequence data of the internal transcribed spacers (ITS) of nuclear ribosomal DNA and chloroplast DNA restriction site data from PCR-amplified genes and genic regions (rbcL,trnK, andrpoC1–C2). Biogeography, morphological evolution, and the existing classification forTrifolium were examined. The genusTrifolium is strongly supported as monophyletic, however, only one small section (Chronosemium) is monophyletic, although the data are in conflict regarding its placement. The two largest sections of the genus, Sects.Lotoidea andTrifolium, are not supported as monophyletic, as currently circumscribed. Many members of Sect.Lotoidea are basal within the genus, supporting previously-proposed hypotheses concerning plesiomorphic morphological characters and a Mediterranean-Mideast biogeographic origin of the genus.     

Molecular phylogenetic study of the heterotrophic dinoflagellate genus Protoperidinium (Dinophyceae) inferred from small subunit rRNA gene sequences

In the present study, we investigated the intrageneric and intergeneric phylogenetic relationships of the heterotrophic marine dinoflagellate genus Protoperidinium. Using single‐cell polymerase chain reaction methods, we determined small subunit ribosomal RNA gene sequences for 10 Protoperidinium species belonging to four sections and two subgenera. Phylogenetic trees were constructed using maximum parsimony, neighbor joining and maximum likelihood methods. We found intraspecific variability of small subunit rDNA sequences in Protoperidinium conicum (Gran) Balech, Protoperidinium crassipes (Kofoid) Balech and Protoperidinium denticulatum (Gran et Braarud) Balech, but not in other species. The small subunit rDNA phylogeny revealed that the genus is monophyletic, but its phylogenetic position within the Dinophyceae could not be determined because of ambiguous basal topologies. Within the genus Protoperidinium, species of the subgenus Archaeperidinium with two anterior intercalary plates (2a) were shown to be monophyletic, but species of the subgenus Protoperidinium with three anterior intercalary plates (3a) were resolved as paraphyletic. The sections Avellana, Divergentia and Protoperidinium were shown to be monophyletic, while the section Conica was paraphyletic. Based on the trees obtained in the present study, most of the traditionally defined sections are supported by molecular phylogeny. It was also indicated that the section Avellana evolved from one of the Conica‐type dinoflagellates.     

Visual effects in great bowerbird sexual displays and their implications for signal design

It is often assumed that the primary purpose of a male''s sexual display is to provide information about quality, or to strongly stimulate prospective mates, but other functions of courtship displays have been relatively neglected. Male great bowerbirds (Ptilonorhynchus nuchalis) construct bowers that exploit the female''s predictable field of view (FOV) during courtship displays by creating forced perspective illusions, and the quality of illusion is a good predictor of mating success. Here, we present and discuss two additional components of male courtship displays that use the female''s predetermined viewpoint: (i) the rapid and diverse flashing of coloured objects within her FOV and (ii) chromatic adaptation of the female''s eyes that alters her perception of the colour of the displayed objects. Neither is directly related to mating success, but both are likely to increase signal efficacy, and may also be associated with attracting and holding the female''s attention. Signal efficacy is constrained by trade-offs between the signal components; there are both positive and negative interactions within multicomponent signals. Important signal components may have a threshold effect on fitness rather than the often assumed linear relationship.     

Biosystematic studies on the genus Heloniopsis (Melanthiaceae) I. Phylogeny inferred from plastid DNA sequences and taxonomic implications

Based on a combined dataset of plastid DNA sequences (atpB‐rbcL, trnG, trnL‐trnL‐trnF, trnK 5' intron and matK) from 60 individuals, we conducted parsimony and likelihood analyses to clarify the phylogenetic relationships among the six species and three varieties that are commonly recognised in Heloniopsis, in addition to the related genera Ypsilandra and Helonias, using Chamaelirium and Chionographis as an outgroup. According to the single most parsimonious tree, which was identical to the maximum‐likelihood tree in topology, Helonias, Ypsilandra and Heloniopsis are all monophyletic with 100% bootstrap support (BS). In Heloniopsis, there are two highly supported clades (BS 94–97%): a clade of Korean species and a clade of Japanese and Taiwanese species. The latter clade comprised the following four subclades (BS 99–100%): 1) H. orientalis var. orientalis, 2) H. orientalis var. breviscapa and var. flavida, 3) H. kawanoi and 4) H. leucantha and H. umbellata. Because subclades 1 and 2 did not form a monophyletic group, and do show clear morphological differences – including nectary position, nectary‐sac structure and leaf margin undulation – they should be distinguished at the species level: H. orientalis for subclade 1 and H. breviscapa for subclade 2. In subclade 2, neither var. breviscapa nor var. flavida was monophyletic; instead, var. breviscapa plus var. flavida (thick‐leaved entity) was monophyletic (BS 62–63%) and var. flavida (thin‐leaved entity) was monophyletic (BS 86–87%). As var. breviscapa and var. flavida (thick‐leaved entity) share basally ± pinkish wide tepals and dark‐coloured thick leaves, in contrast to var. flavida (thin‐leaved entity), which has completely white narrow tepals and light‐coloured thin leaves, the two varieties should may be kept distinct after the merge of var. flavida (thick‐leaved entity) with var. breviscapa.     

Molecular phylogeny of Allomyces macrogynus: Congruency between nuclear ribosomal RNA- and mitochondrial protein-based trees

We have sequenced the nuclear and mitochondrial small subunit rRNA genes (rns) and the mitochondrial genes coding for subunits 1 and 3 of the cytochrome oxidase (cox1 and cox3, respectively) of the chytridiomycete Allomyces macrogynus. Phylogenetic trees inferred from the derived COX1 and COX3 proteins and the nuclear rns sequences show with good bootstrap support that A. macrogynus is an early diverging fungus. The trees inferred from mitochondrial rns sequences do not yield a topology that is supported by bootstrap analysis. The similarity and the relative robustness of the nuclear rns and the mitochondrial protein-derived phylogenetic trees suggest that protein sequences are of higher value than rRNA sequences for reconstructing mitochondrial evolution. In addition, our trees support a monophyletic origin of mitochondria for the range of analyzed eukaryotes. Correspondence to: B. Franz Lang     

What is the phylogenetic placement of Dipteronia dyerana Henry? An example of plant species placement based on nucleotide sequences

Abstract

DNA sequence data have been widely used to evaluate species delimitations and examine infraspecific relationships. However, species placements inferred from different nucleotide sequences are frequently in conflict. As an example of plant species placement based on nucleotide sequences, the phylogenetic placement of Dipteronia dyerana Henry (Aceraceae) was analyzed in the present study. The study species included eight Acer species (from different sections of Acer), two Dipteronia species, and two outgroup taxa. Phylogenetic trees based on five datasets (ITS, trnL‐F, trnD‐trnT, psbM‐trnD, and rpl16 regions) as well as their combined datasets were generated by using maximum parsimony (MP) and maximum likelihood (ML) analyses. Further analyses were conducted to compare the strict consensus trees based on single regions and the combination of different regions. The results revealed a significant discrepancy among the phylogenetic placements of D. dyerana, inferred from various sequences. Phylogenetic trees using MP analysis based on trnD‐trnT, rpl16, and the four chloroplast combined sequences supported the genus Dipteronia as a monophyletic group, while in the other trees D. dyerana was positioned either in parallel with D. sinensis and Acer species or within the genus Acer. In ML analysis, only rpl16 and the four chloroplast combined sequence datasets supported the genus Dipteronia as a monophyletic group. We concluded that, although significant genetic differentiation occurred between D. dyerana and D. sinensis, D. dyerana was more advanced than D. sinensis. However, whether Dipteronia is monophyletic remains to be further investigated, e.g., by using more closely related taxa and more sequences. Furthermore, in addition to internal transcribed spacer sequences, more chloroplast gene sequences should be used for phylogenetic analyses of species.     

Ribosomal RNA sequence comparisons demonstrate an evolutionary relationship betweenZygnematales and charophytes

The nuclear-encoded small subunit ribosomal RNA (rRNA) sequences were determined forGenicularia spirotaenia, Mesotaenium caldariorum, andStaurastrum spec. (Zygnematales) to elucidate the evolutionary position of these green algae. Results of neighbour-joining and maximum parsimony phylogenetic analyses support a monophyletic origin of theZygnematales within the evolutionary assemblage defined by theCharophyceae (sensuMattox & Stewart) and land plants. TheZygnematales/Charophyceae/land plants are evolutionarily distinct from the monophyletic lineage defined by theChlorodendrales, Pseudoscourfieldiales, and theMicrothamniales/Chlorophyceae. In memoriamRobert W. Hoshaw.     

Molecular systematics of the Old World Astragalus (Fabaceae) as inferred from nrDNA ITS sequence data

This study represents a nuclear rDNA ITS-based phylogenetic analyses of a greater sampling of the Old WorldAstragalus compared to our previous work (212 vs. 134 taxa). Phylogenetic relationships among 212 species (213 accessions) of the Old WorldAstragalus, including newly segregated monotypic genusPodlechiella, the two aneuploid New WorldAstragalus, and five related genera, were inferred from analyses of nuclear rDNA ITS sequences using maximum parsimony. A total of 658 nucleotide sites and four binary characters for indels were analyzed. The results of phylogenetic analyses suggest sect.Phyllolobium, comprising mostly the Chinese species, is placed outside of the so-calledAstragalus s. str. and is a well-supported monophyletic group. The monotypic annual segregate genusThlaspidium (≡Astragalus sect.Thlaspidium, A. thlaspi), is clearly nested withinAstragalus s. str. Among the many sections analyzed here, only sects.Cenanthrum, Caraganella, Eremophysa, Incani, Laxiflori, andLotidium are strongly supported as monophyletic. Our analysis, in agreement with previous studies, shows that the North American euploidAstragalus species are scattered throughout the Old World groups of the genus.     

Monophyly of the family Desmoscolecidae (Nematoda,Demoscolecida) and Its Phylogenetic position inferred from 18S rDNA sequences

To infer the monophyletic origin and phylogenetic relationships of the order Desmoscolecida, a unique and puzzling group of mainly free-living marine nematodes, we newly determined nearly complete 18S rDNA sequences for six marine desmoscolecid nematodes belonging to four genera (Desmoscolex, Greeffiella, Tricoma and Paratricoma). Based on the present data and those of 72 nematode species previously reported, the first molecular phylogenetic analysis focusing on Desmoscolecida was done by using neighbor joining (NJ), maximum parsimony (MP), maximum likelihood (ML) and Bayesian inference (BI) methods. All four resultant trees consistently and strongly supported that the family Desmoscolecidae forms a monophyletic group with very high node confidence values. The monophyletic clade of desmocolecid nematodes was placed as a sister group of the clade including some members of Monhysterida and Araeolaimida, Cyartonema elegans (Cyartonematidae) and Terschellingia longicaudata (Linhomoeidae) in all the analyses. However, the present phylogenetic trees do not show any direct attraction between the families Desmoscolecidae and Cyartonematidae. Within the monophyletic clade of the family Desmoscolecidae in all of the present phylogenetic trees, there were consistently observed two distinct sub-groups which correspond to the subfamilies Desmoscolecinae [Greeffiella sp. + Desmoscolex sp.] and Tricominae [Paratricoma sp. + Tricoma sp].     

Stealing behavior and the maintenance of a visual display in the satin bowerbird

Honest signals that indicate male quality have been observedin many species and are thought to have evolved to allow malesto assess rivals accurately and respond to "cheaters." Femalescould potentially also use the same honest signals as reliableindicators of male quality. In bowerbirds, the numbers of specificbower decorations may serve as an honest signal of male quality:this study investigates whether decoration stealing among malesatin bowerbirds at the Bunya Mountains, Australia, may alsoinvolve honest signals. In this study, we aimed to determine1) predictors for the degree to which individual male satinbowerbirds steal, and are stolen from, and 2) predictors forwhy some male pairs interact by stealing, whereas other pairsdo not. We also assessed how experimentally standardizing thenumber of decorations on bowers would affect the 1) frequencyof stealing, 2) specific interactions among males, and 3) distributionof decorations across bowers. Bower decorations were labeledand tracked through one breeding season. Males that were successfulstealers, stole from other successful stealers, had many feathersand bottle tops on their bowers and painted their bower wallsoften. Male pairs were more likely to interact by stealing iftheir bowers were in close proximity. Most of the stealing observedwas of a reciprocal nature. After we standardized the numbersand types of decorations on a small group of males' bowers,the mean number of daily stealing gains and the total numberof males interacting by stealing did not change. In addition,no significant novel stealing interactions were initiated afterthe manipulation. The average number of all bower decorationsand the average number of rosella feathers on a given male'sbower prior to the manipulation were proportional to the averagenumbers for the period after the manipulation. Furthermore,males that originally had better collections of decorationstended to suffer fewer losses due to stealing after the manipulation.Our results suggest that the total number of decorations, thetotal number of rosella feathers on a male's bower, and possiblystealing behavior, may form part of the basis of an honest signalindicating male quality and therefore might be correlated withmating success.     

Relationships among the major lineages of Dictyoptera: the effect of outgroup selection on dictyopteran tree topology

Abstract Dictyoptera, comprising Blattaria, Isoptera, and Mantodea, are diverse in appearance and life history, and are strongly supported as monophyletic. We downloaded COII, 16S, 18S, and 28S sequences of 39 dictyopteran species from GenBank. Ribosomal RNA sequences were aligned manually with reference to secondary structure. We included morphological data (maximum of 175 characters) for 12 of these taxa and for an additional 15 dictyopteran taxa (for which we had only morphological data). We had two datasets, a 59‐taxon dataset with five outgroup taxa, from Phasmatodea (2 taxa), Mantophasmatodea (1 taxon), Embioptera (1 taxon), and Grylloblattodea (1 taxon), and a 62‐taxon dataset with three additional outgroup taxa from Plecoptera (1 taxon), Dermaptera (1 taxon) and Orthoptera (1 taxon). We analysed the combined molecular?morphological dataset using the doublet and MK models in Mr Bayes , and using a parsimony heuristic search in paup . Within the monophyletic Mantodea, Mantoida is recovered as sister to the rest of Mantodea, followed by Chaeteessa; the monophyly of most of the more derived families as defined currently is not supported. We recovered novel phylogenetic hypotheses about the taxa within Blattodea (following Hennig, containing Isoptera). Unique to our study, one Bayesian analysis places Polyphagoidea as sister to all other Dictyoptera; other analyses and/or the addition of certain orthopteran sequences, however, place Polyphagoidea more deeply within Dictyoptera. Isoptera falls within the cockroaches, sister to the genus Cryptocercus. Separate parsimony analyses of independent gene fragments suggest that gene selection is an important factor in tree reconstruction. When we varied the ingroup taxa and/or outgroup taxa, the internal dictyopteran relationships differed in the position of several taxa of interest, including Cryptocercus, Polyphaga, Periplaneta and Supella. This provides further evidence that the choice of both outgroup and ingroup taxa greatly affects tree topology.     

Megachiropteran Evolution Studied with 12S rDNA and c-mos DNA Sequences

Recent studies of mitochondrial DNA sequences have indicated the requirement for substantial revisions of the morphological understanding of the phylogeny of Megachiroptera (Pteropodidae). There is disagreement between studies as to what these revisions might be. This investigation was undertaken to expand the number of studied species and to add the first data from a nuclear gene sequence. For 12S ribosomal DNA (aligned length of 405 positions), 75 Megachiroptera (50 species in 20 genera) and two outgroup species were sequenced. For the oncogene c-mos (aligned length of 488 bases), 56 Megachiroptera (42 species in 19 genera) were sequenced and three eutherians from GenBank used as outgroups.The root of the megachiropteran phylogeny cannot be determined with the present data. Nyctimene, the only studied insectivorous genus (Paranyctimene not being included), plus Notopteris, the only long-tailed megachiropteran, form the sister clade to the other genera in combined analyses. Several alternative rootings are not rejected by the data, suggesting a rapid early radiation. Generic distributions indicate that this may have occurred in Melanesia. The results confirm that the subfamily Macroglossinae is not monophyletic with the long tongued phenoptype arising at least twice and support the existence of a major clade including a monophyletic endemic African component and biogeographically neighboring genera such as Rousettus and Eonycteris. The phylogenetic position of one African genus, Eidolon, remains uncertain.A cynopterine section (excluding Nyctimene and Myonycteris) is supported, albeit weakly, as a monophyletic group. Pteropus and the related, possibly polyphyletic genus Pteralopex, are unexpectedly basal compared to previous molecular studies.     

A molecular phylogeny of celtidaceae and ulmaceae (Urticales) based onrbcL Nucleotide sequences

On the basis of 1,290 bp sequences of the chloroplast generbcL, a molecular phylogeny of seven of nine genera of the Celtidaceae and four of six genera of the Ulmaceae was produced. These data were analyzed together with some other urticalean genera using three methods (i.e., maximum parsimony, maximum likelihood, and neighbor joining methods). Maximum likelihood topology among 18 trees obtained indicated that the Urticales are monophyletic with its common clade splitting basally into two: one leading to a line comprisingAmpelocera (traditionally placed in Celtidaceae) and Ulmaceae, and the other leading to a line comprising the remaining genera of Celtidaceae, Moraceae, and other Urticales. Ulmaceae, to whichAmpelocera is a sister group, are monophyletic, as supported by many lines of morphological evidence. In contrast to Ulmaceae, the monophyly of Celtidaceae (excludingAmpelocera) was not supported, and resolution of relationships of Celtidaceae with other Urticales, as well as of those within the family, is left for future study.     

A preliminary genetic distinctness of four Coilia fishes (Clupeiformes: Engraulidae) inferred from mitochondrial DNA sequences

In order to understand the genetic distinctness between four Coilia fishes, i.e. (C. ectenes, C. e. taihuensis, C. mystus, and C. grayii) the combined cytochrome b (cytb), 12S rRNA and 16S rRNA gene sequences were obtained and analysed. The results are as follows: (1) Neighbour-joining (NJ) and maximum parsimony (MP) trees were built with 1000 bootstrap replicates. They supported that Coilia fishes consisted of two clades: C. grayii form a monophyletic group, and the remaining samples form the other monophyletic group; (2) The topological differences between the NJ tree and the MP tree are checked by Templeton test, indicating that their differences are insignificant (P > 0.05); and (3) Kimura two-parameter distances between the samples of C. ectenes, C. e. taihuensis, and C. mystus all do not exceed 1.6%, and most of them are between 0 and 0.9%. Coilia ectenes, C. e. taihuensis, and C. mystus are closely related and their differences may be under subspecies. The text was submitted by the authors in English.     

Molecular phylogeny of the Herpestidae (Mammalia, Carnivora) with a special emphasis on the Asian Herpestes

Until now, phylogenetic studies of the mongooses (Carnivora, Herpestidae) have not included an exhaustive sampling of the Asian members of this family. In this study, we used mitochondrial (Cytochrome b and ND2), nuclear (β-fibrinogen intron 7 and Transthyretin intron 1) sequences from almost all of the recognized mongoose species to produce a well-resolved phylogeny of the Herpestidae. We also performed molecular dating analyses to infer divergence dates of the different lineages within the Herpestidae. Our results confirmed the paraphyly of the Herpestes genus and other phylogenetic relationships, which previously had only been moderately supported. The Asian herpestid species were found to form a monophyletic group within the Herpestidae. Within the Asian species, a cyto-nuclear conflict was discovered between the small Indian mongoose (Herpestes auropunctatus), the Indian gray mongoose (Herpestes edwardsii) and the Javan mongoose (Herpestes javanicus), which may have occurred through interspecific hybridization. This study inferred an Early Miocene origin for the Herpestidae and a Middle Miocene origin for the Asian mongooses.     

Preferences for coloured bower decorations can be explained in a nonsexual context

The sensory bias model of sexual selection suggests that elaborate male secondary sexual traits evolved to exploit biases in the female's sensory system. Such biases may have evolved in a nonsexual context. Male bowerbirds build and decorate elaborate structures, bowers, which function as targets of female choice. The colour of decorations used on bowers appears to be important in determining a male's mating success. We tested two predictions made by the sensory bias model, using cache presentation experiments of artificially coloured grapes made to captive bowerbirds of five species. We first searched for evidence of ancestral biases for certain colours that could explain current colour preferences across species. We found no single parsimonious explanation for ancestral patterns of colour preference across the family. We next tested whether female preference patterns could be explained in a nonsexual, foraging, context. For both of the species where sufficient data could be collected, female foraging preferences for grapes were significantly related to male preferences for grapes used as bower decorations. Our results suggest that choice of bower decoration colour may have evolved to exploit a bias in the female's sensory system, originally shaped by selection on foraging practices. Copyright 2003 Published by Elsevier Ltd on behalf of The Association for the Study of Animal Behaviour.