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Samples of longhorn sculpin (Myoxocephalus octodecemspinosus) were exposed to sediment contaminated with crude oil or pulp and paper mill effluent for periods up to 13 months in the laboratory. Other samples were collected at sites where crude oil or effluent from a pulp and paper mill are discharged. The intensity of gill infections of Trichodina spp. on exposed fish was significantly higher than on controls 5, 9, and 13 months after exposure. The intensity of the ciliates was also greater on sculpins collected near an oil-receiving terminal than on those sampled 5 km from the polluted site. Field collections of longhorn and shorthorn (Myoxocephalus scorpius) sculpins at and distant from a pulp and paper mill had high and low intensities of the ciliates, respectively. Similarly, the intensity of trichodinid ciliates was also significantly greater in longhorn sculpins exposed to effluent-contaminated sediment than in controls 5 months after exposure. The results suggest that the intensity of gill-inhibiting species such as trichodinids in susceptible fish hosts increases after chronic exposure to crude oil and to pulp and paper mill effluent, and the parasites may serve as indicators of pollution.

We conducted extensive field observations (369.6 h) and surveys of 36 preworker, multiple-foundress colonies of the social wasp Polistes fuscatus. We observed 48 intrusions by foreign conspecifics in 18 of 36 colonies. The rates of intrusion by foreign females, about 1 intrusion per colony each day, did not differ among observations conducted approximately 22, 39, and 48 days after nest initiation. Thus, it appears that usurpation pressure is both intense and constant throughout the preworker stage of the colony cycle. None of the observed intrusions resulted in the replacement of resident foundresses, although surveys revealed that 2 of 36 multiple-foundress colonies were usurped. All 48 intrusions were by females that were unlikely to be closely related to the colonies they attempted to usurp. Resident foundresses exhibited highly intolerant behaviour toward intruders, and evicted them within 40 s of their landing on the nest. There was a pronounced division of labour between queens and subordinates in colony defence. When present together on the nest, queens were significantly more involved than their subordinates in repelling intruders. The vast majority of intruder evictions did not involve cooperation or joint effort by cofoundresses. Therefore, the ability of multiple foundresses to successfully defend against usurpation is probably due to the decreased probability that their nest is left unattended.

Bombus moderatus Cresson, 1863 occurs in the northern and western regions of North America and reaches its southern limit in Alberta. In 1915, the southernmost record was Banff; by 1987, it had appeared in Kananaskis Country, 40 km southeast of Banff, and by 2010, it had spread 80 km farther east to become one of the more common bumble bee species in Calgary, where it had never been previously recorded. This represents a rate of spread over the last 20 years of about 4 km/year. The simplest hypothesis that can account for this change is that it is just a continuation of the natural expansion of its range since the end of the last ice age. An alternative hypothesis is that it is filling the niche vacated as a result of the decline in another species, Bombus occidentalis Greene, 1858.

Videotaped observations (371.3 h) were conducted in 1995, 1996, and 1997 on 50 multiple-foundress colonies of the social wasp Polistes fuscatus. Observations were made during the mid-preworker, late-preworker, and early-postworker stages of the colony cycle. The vast majority of lost subordinate cofoundresses (62 of 77) disappeared during the time interval from 2 weeks before to 4 weeks after the emergence of the first workers. The loss of subordinates did not appear to be the result of senescence or foraging-related mortality. Lost subordinates were from productive and presumably healthy colonies. In colonies containing two or more subordinates, lost subordinates had significantly greater dominance ranks than expected. There was no behavioural evidence that lost subordinates were evicted from their colony by queens, other subordinate foundresses, or workers. Lost subordinates were not observed to renest, join sister colonies, or adopt orphaned nests. Our results indicate that lost subordinates leave colonies of their own volition. Indirect evidence from other studies suggests that subordinates may disperse and usurp colonies from other sites.

The protein constituents of the larval diets of queen and worker honeybees were separated by continuous paper electrophoresis. The electrophoretic patterns of royal jelly of any age and the early worker diet were similar and comprised five ninhydrin-reactive bands or fractions. Fraction 1 (nearest the cathode) contained lysine as a free amino acid. Fractions 3 and 4 appeared to be complex polypeptides. Alanine, asparagine, aspartic acid, glutamic acid, glycine, histidine, isoleucine and/or leucine, lysine, phenylalanine, threonine, tyrosine, valine, and an unidentified substance were found in chromatograms of the acid hydrolyzate of fraction 3; the hydrolyzate of fraction 4 contained the same amino acids except for threonine. Fractions 2 and 5 were not characterized. Electrophoresis of the diet of worker larvae older than 3 days showed a pronounced fading of all bands, attributable to the dilution of the solids by the addition of honey which occurs at this time. There appeared to be no qualitative differences between the protein fractions of royal jelly and worker diet which would account for the differentiation of female honeybees into queens and workers. The decrease with age in the percentage of protein in the worker diet may be significant.

Seventeen species of Coleoptera, Lepidoptera, Diptera, and Hymenoptera showed chemical differences by the method of paper chromatography in an evaluation of the method for taxonomic purposes. The analyses were complicated by pattern differences evident in larval, pupal, and adult stages of some species. Geographic isolates of Malacosoma disstria Hbn. as well as of Chamaepsila rosae (F.) and physiological entities within Pristiphora erichsonii (Htg.) show identical patterns; however, differences are found at specific levels. Paper chromatography is therefore a valuable taxonomic tool, especially as the technique is capable of considerable refinement.

A new ultramicromethod for the quantitative estimation of amino acids by paper partition chromatography is described. The material required and the procedure adopted are detailed. As an application of this new method, a quantitative estimation of the free amino acids present in the blood of the last larval instar of Galleria mellonella (L.) is presented. The results obtained, when converted into total amino nitrogen, compare favorably with total amino nitrogen results already published in the literature.

Some time ago during informal discussions, Blake Reeves suggested that the paradigm of biochemical adaptation was in need of closer attention and definition. What are biochemical adaptations? How do we probe their significance and mechanisms? Does anything useful come out of such analyses? 1 decided to respond to this suggestion before I grew too old, and thanks to a small grant from the Natural Sciences and Engineering Research Council of Canada, a group of us assembled at Lake Louise, Alberta, from February 7 to 9, 1987, to see how we could rise to the challenge. My plan for analysis of these questions was based on my own experience. For many years now, researchers in my laboratory have been taking advantage of the observable fact that some living systems are "better adapted" to (are better able to cope with) low 0, availability than is man. Marine mammals, for example, are able to hold their breath for periods ranging from several minutes to over an hour during diving; some fishes are able to survive days to weeks of hypoxia; diving turtles and several invertebrate groups are able to survive months of near or even total 0, lack. Our initial goal, to discover if universal underlying mechanisms were to be found in these various examples of hypoxia adaptation, led to a remarkably simple and unifying theory. In its simplest form that theory states that the most effective defence strategy against hypoxia used by "good animal anaerobes" involves (i) controlled metabolic arrest coupled with (ii) controlled channel arrest. As 0, availability is reduced, at cell, tissue, organ, or even organism level, the energy deficit is not made up by anaerobic mechanisms. Instead, by isolating the cell interior (by arresting ion translocation through ion-specific channels), the need for maintenance energy (for ATP) is reduced and cell metabolic rate then can be drastically decreased. Our current research focusses on this adaptable coupling between metabolic and membrane functions for strictly theoretical reasons. Meanwhile, for many clinical scientists this theoretical research has been usefil and stimulating because it supplies a theoretical framework within which to organize their attuck on the all-too-practical problem of protecting tissues of patients against hypoxia. Such interacting areas include research on cardiac arrest, stroke, acute renal failure, liver ischemia, lung injury, respiratory defence syndrome, claudication, shock, and organ transplant. Thus I was satisfied that we had learned a lot about hypoxia adaptations in animals and that the work was useful to more applied fields. My challenge to each of the symposium participants was to avoid as much as possible repeating previous papers, lectures, or seminars and instead to closely examine his or her particular "system" in terms of adaptable versus constrained properties, thus outlining how it can evolve. Learning what is adaptable and what is unchangeable comes from the close comparison in different environments of macromolecules, cells, tissues, organs, or even organisms in "sensitive" versus "tolerant" species. By working out defence strategies utilized in nature against any given parameter, we hope to automatically supply the ingredients for a theoretical framework for defending more sensitive living systems against that same parameter. Thus we have two goals (or rationales) for our workshop: (i) identifying defence strategies against environmental perturbation for use in more applied fields and (ii) redefining the paradigm of biochemical adaptation in more fully modern terms.

Despite their temperate to subarctic geographic range, American martens (Martes americana) possess a thermally inefficient morphology. The lack of morphological adaptations for reducing thermal costs suggests that marten may use behavioral strategies to optimize thermal budgets. During the winters of 1989–1990 and 1990–1991, we radio-collared and monitored the diel activity of 7 martens. A log-linear model suggested that the presence or absence of light was the only factor associated with marten activity patterns (p

Reproducible live wet weights may be obtained for medium to large larvae of Metriocnemus knabi and Chironomus attenuatus after blotting them on filter paper for 1 min. To obtain reliable measures of wet weight for smaller larvae the blotting time must be reduced in proportion to the surface area/volume ratio of the larvae. Dry weights are easily obtained by oven drying at 60 °C for 24 h but drying for several days does not affect the results. A temperature of 100 °C decreases die percentage dry matter in C. attenuatus. Both species display an increase in percentage dry matter with increasing size. The extent to which the gut is filled with food has no effect on the percentage dry matter. Attempts to determine dry weight directly from preserved larvae were unsuccessful.

Hemolymph was collected from recently fed desert locusts either by adsorption onto filter paper, or by centrifugation and methanol extraction. Whole hemolymph caused both the short-circuit current (Isc) and open-circuit transepithelial electropotential difference (PD) across locust recta mounted in Ussing-type chambers to double during the steady-state period. Methanol extracts of hemolymph caused similar but smaller increases in Isc. The transepithelial resistance (R) did not change. Simultaneous measurements of 36Cl− fluxes indicated that all of the increase in Isc following stimulation could be accounted for by a parallel increase in net Cl− absorption from the lumen side. With the exception of an initial small biphasic fluctuation in Isc, stimulation by hemolymph exhibited identical characteristics to those produced by submaximal dosages of corpora cardiaca (CC). Cardiatectomy drastically reduced the stimulatory activity of hemolymph, suggesting that this neuroendocrine organ is the source of the active factor (chloride transport stimulating hormone (CTSH)) in hemolymph.

Nineteen free amino acids and four ninhydrin-positive compounds were detected in the haemolymph of fifth-instar nymphs of Rhodnius prolixus by the technique of thin-layer chromatography. On the sixth day after feeding, tyrosine and tryptophan appeared in the haemolymph. Their concentration increased until the 12th day when testing stopped. The concentrations of alanine, asparagine, cystine, isoleucine, phenylalanine, and threonine fluctuated moderately from day to day. The results obtained by thin-layer chromatography differed from those of a similar study in which the technique of paper chromatography was used.

An extract of each of Aedes aegypti (L.), A. atropalpus (Coq.), and Culex pipiens (L.) was shown by paper chromatography to contain 12 ninhydrin-staining peptides. None of these peptides from the A. aegypti extract was capable of eliciting skin reactions in a volunteer sensitive to A. aegypti bites. A reaction equivalent to that caused by a mosquito bite was produced by an estimated 10−3 g of dialyzed A. aegypti extract from which the ninhydrin-staining peptides had been removed. Of the solvents tested in attempting to fractionate this active material, the most suitable was 65% acetone. By this means, A. aegypti extract was shown to contain at least four fractions capable of producing skin reactions in volunteers sensitive to A. aegypti bites.

Freshly caught intermolt lobsters show a highly significant elevation of blood glucose after a few minutes of mild stress. Females show a significantly greater increase than males. The small amounts of other sugars in the blood are great enough to explain the increase in glucose, and chromatographic analysis shows that they diminish under stress. In postmolt animals the stress hyperglycaemia is not as great but is still significant; the difference between the sexes is not apparent. Lobsters held in commercial pounds were found to be in a hyperglycaemic condition. The stress of commercial handling and prolonged fasting brings about significant changes in blood sugars and the sexes react differently. The rather better survival of females under these conditions may also be significant.

We evaluated the quality of information about taxonomic identifications in 710 papers published in seven zoological journals in 2017. We found that only 10.7% of papers cited identification methods, 29.2% made available specimen-level material for later verification, and 6.9% indicated taxon concepts applied to studied animals. Only 4.0% provided details about all three practices, while almost two-thirds provided none. Invertebrate papers were more likely than vertebrate papers to provide identification methods and deposit vouchers, but taxon concepts were rarely provided, and none of the three practices were common in any category. In short, our data suggest that most zoological research is irreplicable. To address this problem, journals should require submitted manuscripts to meet the following guidelines: (1) methods used to identify studied taxa must be stated; (2) literature supporting these identifications must be cited; (3) taxon concept(s) applied to species-level taxa must be indicated; (4) specimen-level material should be available for later examination. We argue that research which falls short of these guidelines is not replicable. We provide recommendations for how authors can better document how studied animals are identified and permit others to verify their identifications, which is necessary for transparent, replicable, and ultimately scientific zoological research.

Managing predators to restore threatened or endangered species is often controversial. Hervieux et al. (2014; Can. J. Zool. 92(12): 1029–1037) report on the efficacy of wolf (Canis lupus L., 1758) reduction as a recovery strategy in the Little Smoky population of boreal woodland caribou (Rangifer tarandus caribou (Gmelin, 1788)) range in Alberta, which generated a lot of media attention. As such, the authors were invited by the journal editor who handled the original paper to write this addendum to provide clarification regarding the methodology used in the original paper. Wolf reduction was conducted by Government personnel in accordance with appropriate policy and laws (i.e., federal and provincial Species at Risk Acts; Alberta Wildlife Act; Alberta Woodland Caribou Policy). University-based researchers were involved only in data analysis and writing, and thus did not require approval by a university-based animal welfare board. Collaboration between independent university-based scientists and government biologists is essential to effective assessment of such controversial management practices. Hervieux et al. (2014; Can. J. Zool. 92(12): 1029–1037) in fact concluded that such wolf reductions, by themselves, would only “buy time” and would not restore woodland caribou alone without effective habitat protection.

Few studies have addressed whether terrestrial insects assess predation risk via chemical cues. We exposed predator-naïve fall field crickets ( Gryllus pennsylvanicus Burmeister, 1838) to filter paper containing the chemical cues of three wolf spiders ( Hogna helluo (Walckenaer, 1837), Rabidosa rabida (Walckenaer, 1837), Rabidosa punctulata (Hentz, 1844)), the house cricket ( Acheta domesticus L., 1758,) and blank filter paper. Crickets exhibited greater immobility and reduced speed of movement when exposed to chemical cues of all three spider species. Crickets exhibited reduced speed with increasing mass of R. punctulata, suggesting that larger spiders may pose a greater risk. Cricket response did not differ between cues of H. helluo fed conspecific crickets versus H. helluo fed house crickets, suggesting that crickets cannot distinguish between cues from H. helluo fed phylogenetically similar crickets. Our work nevertheless demonstrates that naïve field crickets respond to chemical cues of several species of wolf spiders.

In prairie voles, Microtus ochrogaster (Wagner, 1842), the onset of parental caring differs by sex and reproductive condition. Maternal caring is displayed abruptly at parturition, whereas paternal caring intensifies gradually during the reproductive period. To determine if changes in odor responsiveness contribute to sex differences in onset of parental behavior, voles were given a choice to investigate various odors at different times during the reproductive cycle. Subjects were either sexually naïve or mated. Mated pairs cohabited until mid-gestation, late gestation, or 3 days postpartum. Voles crossed a tunnel to explore a row of three filter papers covered with infant odor, orange extract, or saline. Males and females exhibited different odor preferences. Males preferred infant odor to saline and orange extract, whereas females preferred infant odor and saline to orange extract. Mating changed the odor investigative behaviors in both males and females. Some voles vigorously manipulated odor-covered papers. The number of females manipulating the papers increased abruptly at late gestation. The number of males manipulating the papers was particularly high at mid-gestation and after the birth of young. Results suggest that mating and cohabitation in prairie voles influences odor responses in a sex-specific manner.

The comment by Romero and Kannada is presented as a critique of our previous work and suggests that our conclusions are in direct conflict with the historic whaling information reviewed in their paper. However, the critique is based on a misinterpretation of the geographical, temporal, and taxonomic focus of our previous work. The source of the putative conflict appears to stem from the misinterpretation that our results, focused solely on the impact of Basque whaling in the 16th and 17th centuries on the western North Atlantic right whale, were intended to be representative of all whaling of both right and bowhead whales throughout the North Atlantic. To demonstrate this, we briefly review our original results and conclusions and show that the information reviewed by Romero and Kannada does not challenge any aspect of our original work. As such, their comment is not a critique of our paper, but rather a brief review of the history of whaling in the North Atlantic.

With 210 genera and 2010 species, Cyprinidae is the largest freshwater fish family in the world. Several papers, based on morphological and molecular data, have been published and have led to some solid conclusions, such as the close relationships between North American phoxinins and European leuciscins. However, the relationships among major subgroups of this family are still not well resolved, especially for those East Asian groups. In the present paper, the mitochondrial DNA (mtDNA) control region, 896–956 base pairs, of 17 representative species of East Asian cyprinids was sequenced and compared with those of 21 other cyprinids to study their phylogenetic relationships. After alignment, there were 1051 sites. The comparison between pairwise substitutions and HKY distances showed that the mtDNA control region was suitable for phylogenetic study. Phylogenetic analysis indicated that there are two principal lineages in Cyprinidae: Cyprinine and Leuciscine. In Cyprinine, the relationships could be a basal Labeoinae, an intermediate Cyprininae, and a diversified Barbinae (including Schizothroaxinae). In Leuciscine, Rasborinae is at the basal position; Gobioninae and Leuciscinae are sister groups; the East Asian cultrin–xenocyprinin taxa form a large mono phyl etic group with some small affiliated groups; and the positions of Acheilognathinae and Tincinae are still uncertain.

The fossil record of the Echinodermata is relatively complete, and is represented by specimens retaining an abundance of features comparable to that found in extant forms. This yields a half-billion-year record of evolutionary novelties unmatched in any other major group, making the Echinodermata a primary target for studies of biological change. Not all of this change can be understood by studying the rocks alone, leading to synthetic research programs. Study of literature from the past 20 years indicates that over 1400 papers on echinoderm paleontology appeared in that time, and that overall productivity has remained almost constant. Analysis of papers appearing since 1990 shows that research is driven by new finds including, but not restricted to, possible Precambrian echinoderms, bizarre new edrioasteroids, early crinoids, exquisitely preserved homalozoans, echinoids at the K-T boundary, and Antarctic echinoids, stelleroids, and crinoids. New interpretations of echinoderm body wall homologies, broad-scale syntheses of embryological information, the study of developmental trajectories through molecular markers, and the large-scale ecological and phenotypic shifts being explored through morphometry and analyses of large data sets are integrated with study of the fossils themselves. Therefore, recent advances reveal a remarkable and continuing synergistic expansion in our understanding of echinoderm evolutionary history.

Olfaction is the principal sensory modality through which insects locate their food sources, mates, and oviposition sites. Insects offer certain advantages as experimental models for the study of mechanisms of olfaction, and a thorough knowledge of the antennal olfactory sensory cells is essential for such studies. While the sphinx moth, Manduca sexta, has proved to be an especially favorable experimental model in studies of pheromone processing in males, little is known about the female olfactory system, including the antennal olfactory sensilla. In this and another paper in this series, we present the first thorough investigation of the structure, innervation, number, and distribution of sensilla on the antennal flagellum of female M. sexta. The flagellum of the female moth bears eight morphological types of sensilla: two trichoid, two basiconic, one auriculate, two coeloconic, and one styliform complex. In this paper, we describe the two types of trichoid and two types of basiconic sensilla. The first type of trichoid sensillum, a long hairlike sensillum averaging 34 µm in length, is innervated by two bipolar sensory cells, and the second type, a shorter hairlike sensillum averaging 26 µm in length, is innervated by either one or three bipolar sensory cells. The first type of basiconic sensillum is a long peg, averaging 22 µm in length, and the second is a shorter peg, averaging 15 µm in length. Both types of basiconic sensilla are innervated by three bipolar sensory cells. These trichoid and basiconic sensilla have structural features characteristic of insect olfactory sensilla.

Researchers engaged in collecting animal material for stable-carbon and stable-nitrogen isotope analysis are frequently faced with the need to preserve tissues prior to transportation to the laboratory. In many cases, freezing is not possible in the field, so we investigated the potential of several techniques for preserving tissues for this purpose. We also included preservation techniques used for DNA analyses in order to evaluate how they might alter δ13C and δ15N values in tissues and, ultimately, whether archived DNA samples could be used for stable-isotope assay. Tissues included blood and pectoral muscle from quail (Coturnix coturnix japonica) and blood from sheep (Ovis aries). Preservation techniques for blood included freeze-drying (control), drying on precombusted glass-fibre filter paper, and storing in 70% ethanol, 10% buffered formalin, ABI lysis buffer, and Queen's lysis buffer. After 8 weeks, the use of both lysis buffers and formalin resulted in significant depletion of 13C and 15N in blood. Values for samples dried on glass-fibre filter paper or stored in 70% ethanol did not differ significantly from those for the control. Muscle tissue was freeze-dried (control) or stored in 70% ethanol, 10% buffered formalin, or DMSO solution. Both the DMSO and formalin treatments resulted in significant depletion of 13C and 15N compared with the control. Only the 70% ethanol treatment did not result in changes to either isotope ratio in muscle. Where freezing is not possible, we recommend that blood samples be dried or stored in 70% ethanol. Our study provides an estimate of isotopic correction factors that may be applied to tissues archived for DNA analysis or stored in formalin.

The comment of Dalby and Elliott was triggered by a statement we made in a research note to the effect that our study provided the first experimental evidence of predator-classification abilities in cnidarians. Based on an extensive literature search and the appreciation of our manuscript by the reviewers, at the time of publication we believed that this statement was correct. After reviewing the research articles highlighted by Dalby and Elliott, we concur that the statement is incorrect. We discuss some possible reasons why the articles cited by the authors were not found during our literature search, including the use of technical "jargon". In formulating their comment, the authors make several incorrect assumptions, including (i) that our literature search was limited to a single broad review paper and (ii) that we overlooked key information in at least two of the papers we cited. Also, the authors appear to confound predator recognition and predator classification, as some of the articles they cite do not examine predator-classification abilities. Finally, they give the impression that predator-classification abilities are ubiquitous in cnidarians. This appears to be an overstatement, since a number of published studies clearly indicate high variability in the ability of cnidarians to (i) recognize predators and (ii) respond "correctly" according to the relative threat they represent.

The comment by Messier and Joly on a paper by Eberhardt (L.L. Eberhardt. 1997. Can. J. Zool. 75: 1940-1944) suggests that the data in the earlier paper do not demonstrate a regulatory effect of wolves (Canis lupus) on their ungulate prey. It appears that the disagreement results from the use of quite different models, with Messier's approach (F. Messier. 1994. Ecology, 75: 478-488) apparently depending on the assumption of an equilibrium between wolf abundance and prey abundance, while Eberhardt's model depicts non-equilibrium conditions. Some questions having to do with duplications in secondary data sources are further examined.

This is the fifth and final paper in a series treating the Simuliidae of Sri Lanka, and it contains a checklist of the species in the country. In this paper are described three new species of Simulium (Simulium): all stages of Simulium subpalmatum and Simulium cruszi (except the larva) and the male and pupa of Simulium paranubis. The female, male, and pupa of Simulium (Simulium) consimile and S. (S.) striatum are redescribed and the larva of S. (S.) consimile is described for the first time. Taxonomic comparisons are made with related species and keys are provided to separate the eight Sri Lankan species in the subgenus.

Recent cladistic phylogenies of the Platyhelminthes, especially the parasitic species, use for synapomorphies several characters of the spermatozoa, together with other characters. This paper reinvestigates synapomorphies based on sperm characteristics. The outgroup usually chosen for such studies on the parasitic Platyhelminthes (Cercomeria) is the "Dalyelliida" or "Dalyellioida," generally considered a paraphyletic group, but sperm structure in this group shows great variation. In this paper, the Typhloplanoida, which have a plesiomorphic structure (two free axonemes), are considered the outgroup. One of the synapomorphies recently proposed for the Neodermata is "spermatozoon with axonemes incorporated in the cytoplasm." This definition introduces convergences with several other groups of nonparasitic Platyhelminthes. A more precise definition of spermiogenesis, based on a detailed description, is proposed in this paper and avoids homoplasies: "proximodistal fusion of the axonemes." This implies the presence of dorsal and ventral microtubules in the nuclear region of the spermatozoon. This synapomorphy characterizes the Cercomeridea but not the Neodermata (= Udonellidea + Cercomeridea). The character "absence of dense granules in the spermatozoon" should be considered a synapomorphy for the Neodermata and has almost no homoplasies. For the Temnocephalidea, the spiral pattern of the peripheral microtubule row is proposed as a synapomorphy. This character is present in Didymorchis; however, Didymorchis lacks tentacles, which are present in the other genera, and thus the ultrastructural synapomorphy is in conflict with a recently proposed morphological synapomorphy for this group: the presence of tentacles. No synapomorphy of the spermatozoon can be proposed for the Monogenea, but the presence of lateral microtubules lining the axonemes is proposed as a synapomorphy for the polyopisthocotylean Monogenea, and the absence of dorsal and lateral microtubules is proposed as a synapomorphy for the monopisthocotylean Monogenea (this is a reversal of the synapomorphy for the Cercomeridea defined above). The cyclophyllidean Eucestoda show a twisting of the peripheral microtubules of the spermatozoon, which is proposed as a synapomorphy.

Two papers published recently in this journal have examined the relationship between patterns of activity and patterns of body temperature in free-ranging beavers in winter (D.W. Smith, R.O. Peterson, T.D. Drummer, and D.S. Sheputis, 1991. Can. J. Zool. 69: 2178–2182; and A. P. Dyck and R.A. MacArthur, 1992. Can. J. Zool. 70: 1668–1672). I argue that both papers missed their objective, owing to the use of procedures that were inadequate to detect and (or) characterize behavioral or physiological rhythms that were free-running with periods ≠ 24 h.

Partial migration, the phenomenon in which animal populations are composed of both migratory and nonmigratory individuals, is widespread among migrating animals. The proportion of migrants in these populations has direct influences on population genetics and dynamics, ecosystem dynamics, mating systems, evolution, and responses to environmental change, yet there are very few studies that measure the proportion of migrants. This is because existing methods to estimate the proportion of migrants are time-consuming and expensive. In this paper, we demonstrate a new method for estimating the proportion of migrants in a population based on sex ratio measurements. Many partially migratory taxa exhibit sex-biased migration or residency, and in these cases, the sex ratios of migrants and nonmigrants are fundamentally related to the proportion of migrants in the population. We define this relationship quantitatively and show how it can be used to infer the proportion of migrants in a population through a process we term “sex-ratio balancing”. We obtain Bayesian estimates of proportion of migrants and quantify the uncertainty in these estimates with highest posterior density intervals. Lastly, we validate the sex-ratio balancing approach with a Chinook salmon (Oncorhynchus tshawytscha Walbaum in Artedi, 1792) data set. Sex-ratio balancing holds promise as a tool for quantifying partial migration and filling a key data gap about partially migratory taxa.

Notes 2300 Isotopic biogeochemistry of ancient bon collagen is a powerful tool for determining the diet of extinct species. It has been increasingly widely used during the last few years (e.g., Bocherens et al. 1994; Matheus 1995; Grocke and Bocherens 1996). This seemingly simple approach is nonetheless useful only when basic requirements are fulfilled. It appears that Hilderbrand et al. (1996), in their study of extinct cave bear diet using collagen carbonand nitrogenstable isotopes, have left unanswered several key points, which precludes valid conclusions, first by misquoting previous work and second by publishing data that are not interpretable as they stand in the paper. The first point is the misquotation of the conclusions of Bocherens et al. (1994) concerning the cave bear diet. Indeed, Hilderbrand et al. (1996) leave the impression that the interpretation of isotopic-analysis results obtained by Bocherens et al. (1994) is incorrect and that the results presented in that paper, combined with their isotopic-analysis results, indicate an omnivorous diet with a significant meat component for extinct European cave bears. In Bocherens et al. (1994), one key result is that in bears, modern and fossil, isotopic values measured on dentine and bone are not at all equivalent from a palaeodietary point of view. In mammals with brachyodont teeth, dentine collagen reflects a milk diet and thus a higher trophic level than that of the adult. Thus, isotopic-analysis results from such dentine will indicate carnivory, even in species where adults are plant eaters. A crucial consequence is that only adult bone collagen can be used as reflecting adult diet. The discussion in Hilderbrand et al. (1996) mixes all values, from dentine and bone, without taking this point into account. Thus, concluding that the values published in Bocherens et al. (1994) indicate omnivory in cave bears is clearly incorrect. A second point is the fact that the approach used by Hilderbrand et al. (1996) presented several flaws in sampling and assessing the validity of the isotopic measurements, which makes the interpretation of these results highly problematical. From the “sample collection” section of that paper, it appears that Pleistocene samples come from numerous different sites whose age is not known and that are spread all over Europe. It is well known that isotopic signatures are strongly influenced by environmental factors, such as aridity, soil acidity, canopy effect, and season of growth (e.g., Heaton et al. 1986; Ambrose 1991; van der Merwe and Medina 1991; van Klinken et al. 1994; Rodiere et al. 1996). These effects lead to a very large range of isotopic values for a given species when individuals come from different places and different times (e.g., Fizet et al. 1995; Bocherens et al. 1997). An illustration of this high variability can be given by comparing the nitrogen-isotope compositions of large bovine species (Bos and Bison) in three western European upper Pleistocene sites in Belgium (Sclayn: δ15N = 4.7 ± 0.4‰; Bocherens et al. 1997), France (Marillac: δ15N = 6.7 ± 0.9‰; Fizet et al. 1995), and Italy (Paglicci: δ15N = 7.9 ± 1.4‰; Iacumin et al. 1997). It is thus clear that the data presented in Hilderbrand et al. (1996) cannot be interpreted in a palaeodietary perspective, because exact geographical and time origins are not provided in the paper. Also, the lack of individual age indication for the bear samples in Hilderbrand et al. (1996) makes it possible that high δ15N values are due to young age and suckling. Another problem with the isotopic-analysis data from Hilderbrand et al. (1996) is the total absence of information on ancient collagen integrity. It is well known that collagen is altered in ancient bones, and only when chemical purity is assessed can isotope-analysis results be considered with confidence to reflect biogenic signatures (DeNiro 1985; Ambrose 1990; Bocherens 1997). Classical ways of checking collagen purity are to use yield of extraction, %C, %N, and C/N ratio of extracted collagen, and in some cases amino acid analyses. None of these data are provided in Hilderbrand et al. (1996), which precludes any serious interpretation of the presented isotope-analysis results. Finally, so far as the isotopic-analysis data on cave bears presented in Hilderbrand et al. (1996) are concerned, valuable palaeodietary information might be obtained if (i) collagen indegeneity was assessed according to the chemical criteria mentioned above, (ii) time and geographical origins were provided for all samples, (iii) comparisons were made only among herbivores, carnivores, and bears from the same site and the same time period, and (iv) only isotopic-analysis values from adult bone collagen were considered.

It has been suggested that our paper “Closure violation in DNA-based mark–recapture estimation of grizzly bear populations” did not adequately cite the original data analysis from the Prophet River DNA mark–recapture project conducted by Poole et al. (2001). Poole et al. (2001), who designed and collected the DNA data for the Prophet River study, conducted their own mark–recapture analysis and reported other biological findings from the Prophet River dataset, which is detailed in the June 2001 issue of Wildlife Biology. The purpose of our paper was to demonstrate new techniques to explore closure violation rather than to report results from this specific study. Any lack of citation was an oversight and we suggest that readers see Poole et al. (2001) for more details on the Prophet River study.

Managers and policymakers in eastern Canada embrace science-based management of nonindigenous species and may benefit from having comprehensive regional species checklists at subnational jurisdictional levels. In this paper, regional checklists provide an account of the richness of ascidians in eastern Canada. Records of 58 ascidians resulted from reviewing 108 published sources, accessing data from two online databases, and collecting some common indigenous ascidian specimens. Analysis comparing the similarity of species among nine regions indicates that there is greater similarity in species composition between contiguous regions than between noncontiguous regions and suggests that there are four zoogeographic clusters in eastern Canada. Our checklists can inform managers and policymakers of the diversity of the ascidian taxa and can minimize taxonomic uncertainties of established nonindigenous and prospective invading species, for example, by identifying indigenous species that are congeners of nonindigenous species. The maintenance of checklists can be a valuable tool for the management of nonindigenous species as baselines to estimate changes in richness and to document the invasion status of nonindigenous species over time. For example, more importance can be placed on the spread of nonindigenous ascidians from one zoogeographic cluster to another than spread within the same cluster.

Noise can cause marine mammals to interrupt their feeding, alter their vocalizations, or leave important habitat, among other behavioural responses. The current North American paradigm for regulating activities that may result in behavioural responses identifies received levels (RL) of sound at which individuals are predicted to display significant behavioural responses (often termed harassment). The recurrent conclusion about the need for considering context of exposure, in addition to RL, when assessing probability and severity of behavioural responses led us to conduct a systematic literature review (370 papers) and analysis (79 studies, 195 data cases). The review summarized the critical and complex role of context of exposure. The analysis emphasized that behavioural responses in cetaceans (measured via a linear severity scale) were best explained by the interaction between sound source type (continuous, sonar, or seismic/explosion) and functional hearing group (a proxy for hearing capabilities). Importantly, more severe behavioural responses were not consistently associated with higher RL and vice versa. This indicates that monitoring and regulation of acoustic effects from activities on cetacean behaviour should not exclusively rely upon generic multispecies RL thresholds. We recommend replacing the behavioural response severity score with a response/no response dichotomous approach that can represent a measure of impact in terms of habitat loss and degradation.

Nudibranch molluscs of the genus Dendronotus Alder and Hancock, 1845 are widely distributed in the Northern Hemisphere. Taxonomic studies on the genus Dendronotus have been problematic due to high variability in the colour pattern of many species, as well as in the external morphology and anatomy. In the present paper, we studied specimens of Dendronotus from northern Pacific presumably belonging to the species Dendronotus albus MacFarland, 1966 (white frond-aeolis). Molecular and morphological data revealed the existence of two distinct species among the material examined: D. albus, which has a wide range from Kamchatka and the Kurile Islands (from where we report this species for the first time) to California in North America, and the pseudocryptic species Dendronotus diversicolor Robilliard, 1970 (multicolor frond-aeolis), which has been previously considered a junior synonym of D. albus. Dendronotus diversicolor occurs from California, USA, to British Columbia, Canada, in sympatry with D. albus. Dendronotus albus and D. diversicolor can be clearly distinguished by colour pattern, internal and external morphology, and molecular sequence data. Despite some similarities in radular and external morphology between D. albus and D. diversicolor, these two species are phylogenetically distant and belong to different clades within the genus Dendronotus, which suggests convergent evolution.