The study of avian migration has reached sophisticated levels in many areas, including ecology, behaviour, and physiology. Traditional discussions of the evolution of migration, however, have been compromised for several reasons. Previous ideas concerning the ancestral home of migrant species, southern or northern, and whether a partially migratory stage always precedes a fully migratory stage, were not expressed as testable hypotheses. Plotting migratory behaviour on phylogenetic trees has become commonplace and allows tests of traditional hypotheses. Some of these studies are reviewed, lending some support for almost all of the previous ideas. Although phylogenetic mapping helps to frame questions about the evolution of migration in a testable framework, there are two serious issues. First, experimental and observational studies reveal that the expression of migratory behaviour can change rapidly within a lineage, which can violate assumptions of character mapping. In addition, a species distribution model is used to show that current conditions for obligate migratory populations of the chipping sparrow were much restricted at the Last Glacial Maximum, and that the species might have been considered a partial migrant at that time. The expression of migratory behaviour in an extant species might be an artefact of the current inter-glacial period. Only if the rate of gains and losses of migratory behaviour can be incorporated into a phylogenetic mapping exercise will the actual evolutionary pattern of migration be revealed. For example, reconstruction of the ancestral area and the evolutionary history of migratory categories in a clade of New World warblers depended on the assumptions of character state transitions. A second concern is that the trait 'migratory' is too broad for evolutionary analysis and that, if possible, the expression of hyperphagia, Zugunruhe, and navigation could be mapped individually. Loss or suppression of any of these components can lead to sedentary populations, revealing how migratory behaviour can appear and disappear rapidly. A report of low levels of Zugunruhe in a sedentary bird, Saxicola torquata, is reconstructed as derived in a clade of otherwise migratory populations, suggesting that the loss of migration was a result of suppression (but not elimination) of Zugunruhe. When researchers mention the independent origin of migration in a clade, they are most likely referring to the gain or loss of the expression of the ancestral migratory programme, not the de novo evolution of migration per se. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 104, 237–250.
Summary Humans have traded and transported alien species for millennia with two notable step‐changes: the end of the Middle Ages and beginning of the Industrial Revolution. However, in recent decades the world has entered a new phase in the magnitude and diversity of biological invasions: the Era of Globalization. This Special Profile reviews the links between the main drivers of globalization and biological invasions and examines state‐of‐the‐art approaches to pathway risk assessment to illustrate new opportunities for managing invasive species. Income growth is a primary driver of globalization and a clear association exists between Gross Domestic Product and the richness of alien floras and faunas for many regions of the world. In many cases, the exposure of these economies to trade is highlighted by the significant role of merchandise imports in biological invasions, especially for island ecosystems. Post‐1950, technical and logistic improvements have accelerated the ease with which commodities are transported across the globe and hindered the traceability of goods and the ease of intercepting pests. New sea, land and air links in international trade and human transport have established novel pathways for the spread of alien species. Increasingly, the science advances underpinning invasive species management must move at the speed of commerce. Increasing transport networks and demand for commodities have led to pathway risk assessments becoming the frontline in the prevention of biological invasions. The diverse routes of introduction arising from contaminant, stowaway, corridor and unaided pathways, in both aquatic and terrestrial biomes are complex. Nevertheless, common features enable comparable approaches to risk assessment. By bringing together spatial data on climate suitability, habitat availability and points of entry, as well a demographic models that include species dispersal (both natural and human‐mediated) and measures of propagule pressure, it is possible to generate risk maps highlighting potential invasion hotspots that can inform prevention strategies. Synthesis and applications . To date, most attempts to model pathways have focused on describing the likelihood of invader establishment. Few have modelled explicit management strategies such as optimal detection and inspection strategies and assessments of the effectiveness of different management measures. A future focus in these areas will ensure research informs response.
Multiple unlinked loci are surveyed in a methodological approach for mammalian systematics that uses genes from the four pathways of genetic transmission: mitochondrial, autosomal, and X and Y sex chromosomes. Each of these components has different properties, such as effective population size, mutation rate, and recombination, that result in a robust hypothesis of evolutionary history. The utility of this experimental design is tested with bats in the family Emballonuridae and the hypothesis that the New World taxa are monophyletic. Parsimony and Bayesian analyses of the individual data sets give generally congruent topologies with high bootstrap proportions and posterior probabilities for monophyletic clades representing species and genera. The mitochondrial gene has significantly faster rates of substitution, higher levels of homoplasy, and a greater degree of saturation than the nuclear genes that contributed to the loss of phylogenetic signal at deeper branches of the tree. However, there is better resolution and support for the more slowly evolving nuclear introns including a New World clade, indicating a single origin of emballonurid bats in the Neotropics (tribe Diclidurini). One novel subtribe has a hard basal polytomy that is unresolved for all of the nuclear partitions, suggesting a rapid burst of evolution during the diversification of genera. © 2008 The Linnean Society of London, Biological Journal of the Linnean Society, 2008, 93, 189–209.
It is argued that the problem of pattern and scale is the central problem in ecology, unifying population biology and ecosystems science, and marrying basic and applied ecology. Applied challenges, such as the prediction of the ecological causes and consequences of global climate change, require the interfacing of phenomena that occur on very different scales of space, time, and ecological organization. Furthermore, there is no single natural scale at which ecological phenomena should be studied; systems generally show characteristic variability on a range of spatial, temporal, and organizational scales. The observer imposes a perceptual bias, a filter through which the system is viewed. This has fundamental evolutionary significance, since every organism is an "observer" of the environment, and life history adaptations such as dispersal and dormancy alter the perceptual scales of the species, and the observed variability. It likewise has fundamental significance for our own study of ecological systems, since the patterns that are unique to any range of scales will have unique causes and biological consequences. The key to prediction and understanding lies in the elucidation of mechanisms underlying observed patterns. Typically, these mechanisms operate at different scales than those on which the patterns are observed; in some cases, the patterns must be understood as emerging form the collective behaviors of large ensembles of smaller scale units. In other cases, the pattern is imposed by larger scale constraints. Examination of such phenomena requires the study of how pattern and variability change with the scale of description, and the development of laws for simplification, aggregation, and scaling. Examples are given from the marine and terrestrial literatures.
The attainment of sexual maturity has been shown to affect measures of sexual size dimorphism (SSD) and adult sex ratios in several groups of vertebrates. Using data for turtles, we tested the model that sex ratios are expected to be male-biased when females are larger than males and female-biased when males are larger than females because of the relationship of each with the attainment of maturity. Our model is based on the premise that the earlier-maturing sex remains smaller, on average throughout life, and predominates numerically unless the sexes are strongly affected by differential mortality, differential emigration, and immigration, or biased primary sex ratios. Based on data for 24 species in seven families, SSD and sex ratios were significantly negatively correlated for most analyses, even after the effect of phylogenetic bias was removed. The analyses provide support for the model that SSD and adult sex ratios are correlated in turtles as a result of simultaneous correlation of each with sexual differences in attainment of maturity (bimaturism). Environmental sex determination provides a possible mechanism for the phenomenon in turtles and some other organisms. © 2014 The Authors. Biological Journal of the Linnean Society published by John Wiley & Sons Ltd on behalf of The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 112, 142–149.
We have used ancestral character state reconstruction and molecular dating to test hypotheses on the evolution of New Zealand alpine cicadas of the genus Maoricicada Dugdale. Gene trees were estimated from mitochondrial DNA and the nuclear loci elongation factor 1-α, period, and calmodulin and species-level relationships were reconstructed using gene tree parsimony. These analyses suggest that the alpine habitat character state had a single origin and that the ancestral Maoricicada lived in low to mid-elevation habitats. Our reconstructions also strongly support the hypothesis that this ancestor was darkly coloured and had increased pubescence, classic adaptations of alpine insects. Using relaxed-clock Bayesian dating methods, we estimated that the radiation of the alpine Maoricicada species was coincident with the late Miocene acceleration in the rate of uplift of the Southern Alps rather than uplift in the early Miocene. These dates are very similar to those of other alpine taxa, indicating that the New Zealand alpine biota is very young. Our reconstructions suggest that the ancestral Maoricicada may have been preadapted to the alpine environment because it existed before the origin of high mountainous habitats, dwelt at mid-to-low altitudes, and yet possessed the classic alpine insect adaptations of heavy pubescence and dark coloration. © 2007 The Linnean Society of London, Biological Journal of the Linnean Society, 2007, 91, 419–435.
In the present study, mitochondrial (mt)DNA sequence data were used to examine the genetic structure of fire-eye antbirds (genus Pyriglena) along the Atlantic Forest and the predictions derived from the river hypothesis and from a Last Glacial Maximum Pleistocene refuge paleomodel were compared to explain the patterns of genetic variation observed in these populations. A total of 266 individuals from 45 populations were sampled over a latitudinal transect and a number of phylogeographical and population genetics analytical approaches were employed to address these questions. The pattern of mtDNA variation observed in fire-eye antbirds provides little support for the view that populations were isolated by the modern course of major Atlantic Forest rivers. Instead, the data provide stronger support for the predictions of the refuge model. These results add to the mounting evidence that climatic oscillations appear to have played a substantial role in shaping the phylogeographical structure and possibly the diversification of many taxa in this region. However, the results also illustrate the potential for more complex climatic history and historical changes in the geographical distribution of Atlantic Forest than envisioned by the refuge model. (c) 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 105, 900824.
The evolution of primates is usually approached from the standpoint of adaptation and interspecific competition. However, climatic and eustatic changes associated with periodic glaciations have had a profound influence on their geographical distribution, favouring the intervention of contingency in evolution. This paper deals with the role of chance and competition in the dispersal and stocking of macaques in the islands of south-east Asia. The genus Macaca is unique among non-human primates for the range of habitats colonized, from continents to islands. We first review current knowledge about the zoogeography of macaques in Sundaland. We point out the inconsisten- cies present in the hypotheses thus far proposed to account for the colonization of shallow- and deep-water islands. We then propose a new perspective of macaque dispersal through the Indonesian archipelago, which takes into account sea-level changes, as well as latitudinal and altitudinal rainforest shifts following climatic cycles during the Quaternary. We envision three steps: (i) dispersal and partial disappearance of the first radiation of macaques; (ii) primary mainland recolonization by pigtailed and longtailed macaques; and (iii) secondary sea-rafting colo- nization by longtailed macaques. This model implies that liontailed, Sulawesi and Mentawai macaques stemmed from pre-glacial remnant populations, whereas pigtailed macaques originated in post-glacial populations that diverged later on. The model accounts for the distribution of longtailed macaques throughout the Indonesian archi- pelago. The riverine habits of this species would have favoured its dispersal by sea rafting, which was otherwise extremely rare for other primate species. Stocking would have been successful for longtailed macaques only in islands where no other macaque competitors were already present. © 2002 The Linnean Society of London, Biological Journal of the Linnean Society, 2002, 75, 555-576. ADDITIONAL KEYWORDS: biogeography - colonization - competition - contingency - island - Macaca - Quaternary - Sunda shelf.
The plethodontid genus Batrachoseps, the slender salamanders, is the most diverse clade of salamanders in western North America, but it has posed taxonomic difficulties because it contains many morphologically cryptic species. A segment of the mitochondrial DNA gene cytochrome b was studied for 278 individuals densely sampled from throughout the range of all 18 described species and several undescribed species. Phylogenetic analyses of the mtDNA data identify six major clades, one corresponding to the subgenus Plethopsis and five within a monophyletic subgenus Batrachoseps. All major clades and most species within these clades display strong phylogeographic structuring. Comparisons of mtDNA and allozyme data show that several allozymically cohesive groups are not monophyletic with respect to mtDNA. We suggest that this phenomenon results from fragmentation of populations, divergence in allopatry, and then recontact and gradual merging of units caused predominantly by male-mediated gene flow. The mtDNA offers evidence that populations were once more isolated than they are now, while the patterns of allozyme variation reflect recent and current interactions among populations. The complex patterns of morphological, allozymic and mtDNA variation associated with the constantly changing geological landscape give insight into the nature of processes responsible for species formation in Batrachoseps. © 2002 The Linnean Society of London. Biological Journal of the Linnean Society, 2002, 76, 361–391.
Ciliates are a diverse group of microbial eukaryotes that exhibit tremendous variety in several aspects of their mating systems. To understand the evolutionary forces driving mating system diversification in ciliates, we use a comparative approach synthesizing data from many ciliate species in light of recent phylogenetic analyses. Specifically, we investigate the evolution of number of mating types, mode of mating type inheritance, and the molecular determinants of mating types across the taxonomic diversity of ciliates, with an emphasis on three well-studied genera: Tetrahymena, Paramecium, and Euplotes. We find that there have been many transitions in the number of mating types, and that the requirement of nuclear reorganization may be a more important factor than genetic exchange in determining the optimum number of mating types in a species. We also find that the molecular determinants of mating types and mode of inheritance are evolving under different constraints in different lineages of ciliates. Our results emphasize the need for further detailed examination of mating systems in understudied ciliate lineages. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 98, 187‐197.
Open vegetation (campinas and campinaranas) associated with white sand patches occurs in the form of islands in a forested matrix throughout the Amazon basin. Bird species restricted to these habitats have patchy distributions, although connectivity may have been influenced by past glacial cycles as a result of the substitution of forest by savanna. Because these landscape changes are a matter of debate in the history of Amazonia, we studied the diversification of Xenopipo atronitens, a white sand specialist, aiming to infer the effects of past climate changes. The split of Xenopipo atronitens from its sister species, Xenopipo uniformis, may be related to Tepuis erosion and retreat of escarpments during the Miocene, or to a dispersal event. Compared with birds from terra firme forest, X. atronitens has low genetic structure. Low levels of unidirectional gene flow were found from the Guyana Shield to adjacent areas. Demographic expansion starting approximately 25 kyr BP was detected for some populations and is probably related to the Last Glacial Maximum and subsequent climate improvement. Landscape genetic analyses indicate that the forested (terra firme) matrix acts as a barrier for the dispersal of X. atronitens. The results of the present study indicate that glacial cycles have deeply influenced Amazonian biogeographical history, demonstrating a complex interaction between forest and nonforest habitats during the Pleistocene. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 110, 60–76.
To examine phylogenetic relationships within the Asian lineage of voles (Microtus) belonging to subgenus Alexandromys, the mitochondrial cytochrome b gene (cytb) was sequenced for its representatives, and the results were compared with the cytogenetic, morphological, and paleontological data. In all the trees inferred from maximum likelihood, parsimony, and Bayesian phylogenetic analyses, the Asian clade is subdivided into highly supported Alexandromys s.s. and moderately supported Pallasiinus lineages. Four subclades are recovered within Alexandromys: (1) Microtus maximowiczii and Microtus sachalinensis; (2) Microtus miiddendorffii s.l., Microtus mongolicus and Microtus gromovi; (3) Microtus fortis; and (4) Microtus limnophilus. Thus, M. limnophilus demonstrates clear affinities to Alexandromys s.s. but not to Microtus oeconomus (subgenus Pallasiinus), which was always regarded as its sibling species. The results obtained indicate M. mongolicus as a member of Alexandromys but not of the Microtus arvalis group, thus being concordant with the cytogenetic data. The mitochondrial data support the species status of M. gromovi; moreover, its placement as a part of a trichotomy with M. miiddendorffii s.l. and M. mongolicus contradicts the traditional affiliation of M. gromovi with M. maximowiczii. The divergence rate of cytb third position transversions in Microtus is estimated at approximately 8% per Myr, which corresponds to approximately 30% per Myr for all substitution types at all codon positions. The maximum likelihood distance based on complete sequence showed a tendency for a progressive underestimation of divergence and time for older splits. According to our molecular clock analysis employing nonlinear estimation methods, the split between Alexandromys and Pallasiinus and basal radiation within Alexandromys date back to approximately 1.2 Mya and 800 Kya, respectively. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 99, 595–613.
Seasonal changes in immunocompetence are predicted by the hypothesized trade-off between reproduction and self-maintenance, whereby immune function is a measure of self-maintenance and reproductive effort is seasonally dependent. We examined seasonal patterns in immunological, haematological and body condition parameters for male and female freshwater fish. In two different populations, the relative size of the spleen and the chemotaxic migration activity of head kidney granulocytes decreased immediately before and after spawning, respectively. Those decreases were accompanied by an increase in haematocrit values shortly before and after spawning in both populations and a decrease in the relative body weight in one population, possibly due to physiological stress caused by increased activity during the spawning period. Breeding-related changes in other measures studied (phagocytosis activity of head kidney granulocytes, blood IgM concentration, white cell count and red cell count) were absent or inconsistent. Some of the results are in line with the idea of a trade-off between reproduction and immune defence. The present data suggest that the differential responses of the immune system may have different temporal patterns, which should be taken into account in immunoecological studies. © 2003 The Linnean Society of London, Biological Journal of the Linnean Society , 2003, 78, 117−127.
The colourful appearance of bird eggshells has long fascinated biologists and considerable research effort has focused on the structure and biochemistry of the avian eggshell matrix. The presence of tetrapyrrole pigments was identified nearly a century ago. Surprisingly, how the concentrations of avian eggshell pigments vary among related species, and whether this variability is associated with either eggshell appearance and/or species life‐history traits, remains poorly understood. We quantified the concentrations of the two key eggshell pigments, protoporphyrin IX and biliverdin, from a diverse sample of eggshells stored at the Natural History Museum, Tring, UK. We explicitly tested how these two pigments are associated with physical measures of eggshell coloration and whether the pigment concentrations and colour diversity co‐vary with phylogenetic affiliations among species. We also tested a series of comparative hypotheses regarding the association between the concentrations of the two pigments and specific life‐history and breeding ecology traits. Across species, the average concentrations of protoporphyrin and biliverdin were positively correlated, and both strongly co‐varied with phylogenetic relatedness. Controlling for phylogeny, protoporphyrin concentration was associated with a higher likelihood of cavity nesting and ground nesting, whereas biliverdin concentration was associated with a higher likelihood of non‐cavity nesting habit and bi‐parental provisioning. Although unlikely to be explained by a single function, the breeding ecology and life history‐dependence of eggshell pigment concentrations in these comparative analyses implies that related species share pigment strategies, and that those strategies relate to broad adaptive roles in the evolution of variation in avian eggshell coloration and its underlying mechanisms. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 106, 657–672.
Granite outcrops represent an isolated island habitat and, in ancient landscapes, may harbour species with complex evolutionary histories. Phylogenetic analysis of these species may reveal the influences of evolutionary processes over long time frames. Phylogenetic relationships from chloroplast and nuclear genome analysis were investigated in Eucalyptus caesia, a bird-pollinated mallee endemic to granite outcrops in the South-western Australian Floristic Region. The results obtained revealed high population and haplotype divergence, suggesting restriction to the specific habitat of granite outcrops over long time frames with genetic drift as the most significant evolutionary force. The hypothesis of derivation of ssp. magna from ssp. caesia was not supported by the pattern of diversity in either the chloroplast or the nuclear genome and the two subspecies were not monophyletic. Eucalyptus caesia displays significant clonality yet little evidence of inbreeding depression, suggesting deleterious mutations causing inbreeding depression have been purged. © 2008 Department of Environment and Conservation. Journal compilation © 2008 The Linnean Society of London, Biological Journal of the Linnean Society, 2008, 93, 177–188.
The general flowering (GF) events of forests in south-east Asia are perhaps the most spectacular phenomena in tropical biology. GF events occur at multiyear intervals. In GF, most dipterocarp species and many plants of other families come into flower and set fruit massively; these species and plants rarely flower except during GF events. GF is unique, because it can occur over thousands of kilometers and involve hundreds of plant species representing diverse families and lifeforms. It also involves strict mast fruiting. Satiation of generalist seed predators has been considered a primary force for GF. However, recent observations indicate that several selective agents rather than a single major factor may shape GF. In addition to the satiation of generalist predators, promotion of pollination could be one of the selective factors for GF, since synchronized flowering of many species causes an increase in pollinator activity through immigration and population growth. Although environmental prediction for better establishment of seedlings may also be involved in GF, no field data have been reported to support this idea. Long-term monitoring and further understanding of GF are essential for the conservation of this unique and diverse tropical forest in south-east Asia, especially in a period of global climatic change. © 2002 The Linnean Society of London, Biological Journal of the Linnean Society, 2002, 75, 233–247.
Large, carnivorous mammals often break their teeth, probably as a result of tooth to bone contact that occurs when carcasses are consumed more fully, a behaviour likely to occur under conditions of food stress. Recent studies of Pleistocene predators revealed high numbers of teeth broken in life, suggesting that carcass utilization and, consequently, food competition was more intense in the past than at present. However, the putative association between diet and tooth fracture frequency was based on a small sample of large, highly carnivorous species. In the present study, a greater diversity of extant carnivorans is sampled, including insectivorous, omnivorous, and carnivorous forms, ranging in size from weasels to tigers. Species that habitually consume hard foods (bones, shells) had the highest fracture frequencies, followed by carnivores, and then insectivorous and/or omnivorous species. Predator and prey sizes were not associated with tooth fracture frequency, but more aggressive species did break their teeth more often. Comparison of the modern sample with five Pleistocene species confirms the previous finding of higher tooth breakage in the past, although some extant species have fracture frequencies that approach those of extinct species. Thus, the Pleistocene predator guild appears to have been characterized by relatively high levels of competition that are rarely observed today. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 96, 68–81.
Sex is generally thought of as meiosis, conjugation, and syngamy, with the primary function of sex believed to be genetic mixing. However, conjugation does not occur with complete automixis, whereas syngamy does not occur with restitutional automixis. Self sex in the forms of automixis and autogamy does not include genetic mixing. Yet sex, including self sex, is necessary for most eukaryotic lineages. What is the purpose of sex without genetic mixing? Obligate self sex is not an evolutionary dead end, but holds the key to understanding the evolutionary origin, function, maintenance, and ubiquity of sex. We extend the rejuvenescence hypothesis that sex provides a necessary developmental reset for multicellular eukaryotes and even many unicellular eukaryotes. Sex reduces additive genetic variance of epigenetic signals, especially cytosine methylation, and of ploidy levels. Furthermore, we argue that syngamy is a modified form of meiosis that maintains ploidy and resets epigenetic signals. Epigenetic resetting is consistent with sex being induced by starvation or desiccation. Diminution of additive genetic variance is consistent with the origin and maintenance of an adaptive trait, sex, that has been present for approximately two billion years. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 98, 707‐728.
Large-scale biogeographical patterns of Sphingidae in the Malesian archipelago are investigated, using Geographic Information System-supported estimates of species ranges determined from a compilation of specimen-label databases. Distribution maps for all species and checklists for 114 islands are presented at http://www.sphingidae- sea.biozentrum.uni-wuerzburg.de. Phenetic analyses of island faunas reveal 'textbook'-like patterns of biogeograph- ical associations in the region, with Wallace's line emerging as the main faunal discontinuity in the region. Further analyses, using partial Mantel statistics, indicate that historical features of geography (such as land bridges formed during periods of lower sea levels) are an important determinant of faunal similarity, but recent dispersal can also explain a significant portion of present day hawkmoth distributions. Faunal turnover in relation to distance between islands is steeper for Smerinthinae than for other subfamilies, indicating different dispersal abilities among higher taxonomic groups. These differences are discussed in the light of life-history differences between the subfamilies. © 2006 The Linnean Society of London, Biological Journal of the Linnean Society , 2006, 89 , 455-468.
The so-called ‘mimic octopuses’ of tropical Indonesia are reputed to mimic up to 13 species of other local marine organisms. We tested for mimicry by allowing individuals of two species of octopus to habituate to divers, then observing and filming two species continuously as they foraged daily in the same open, featureless volcanic sand habitat. Mimicry of a local, abundant flounder occurred commonly during 5 days of natural foraging: nearly 500 episodes were analysed. Both octopus species mimicked the shape, swimming actions, speed, duration, and sometimes the coloration of swimming flounders. During flounder mimicry, octopuses were actively moving and conspicuous, whereas immediately before and after flounder mimicry, they were camouflaged and motionless (sitting or very slowly crawling). Furthermore, when motionless, octopuses assumed body patterns and postures that resembled small sponges, tube-worm tubes, or colonial tunicates, which were among the few objects in the open sand habitat. The key finding was that octopuses used flounder mimicry only when their movement would give away camouflage in this open habitat. In all cases, octopuses used mimicry as a primary defense. Several interactions with fishes and stomatopods were filmed and typical secondary defense behaviours, not mimicry, were used by the octopuses. Foraging occurred twice per day and two tactile feeding tactics were used. Dens and food were not limiting; thus, we observed a highly unusual circumstance of a guild of small, long-armed octopus species that shared the same habitat, den sources, food, activity period, and some behaviours. © 2008 The Linnean Society of London, Biological Journal of the Linnean Society, 2008, 93, 23–38.