bluuebunny/crossref_metadata_2025 huggingface dataset:
Two new gobiid fish species (in Priolepis and Trimma) from the Chagos Archipelago, central Indian Ocean
Authors: Winterbottom Richard
Published: March 2009

Priolepis compita n. sp. is described from specimens from the Chagos Archipelago, but other material indicates an Indo-west Pacific distribution from South Africa to Fiji. Trimma emeryi n. sp. was described and illustrated in colour by Winterbottom in 1984 under the name T. mendelssohni, with a note added in proof stating that it was not that species but represented an undescribed form. Priolepis and Trimma are closely related, differing mainly in the anteroventral extent of the gill opening and in colour pattern. The new Priolepis differs from its congeners in having the vertical bars on the postocular portion of the head and the nape joined by a horizontal line, sometimes staggered, at the level of the dorsal margin of the pupil. Its distribution includes the Kwazulu coast of southern Africa to at least Fiji in the western Pacific. The new Trimma differs from other species in the genus in colour pattern, a number of meristic characters, and in details of fin-ray branching patterns. The new species is recorded definitely only from Chagos and the Gulf of Tadjoura in the Gulf of Aden. Specimens from Fiji apparently represent a closely related species.
Plasma gonadotropin, 17β-estradiol, and 17α,20β-dihydroxy-4-pregnen-3-one levels during luteinizing hormone-releasing hormone analogue and gonadotropin induced ovulation in coho salmon (Oncorhynchus kisutch)
Authors: Kraak Glen Van Der , Dye Helen M. , Donaldson Edward M. , Hunter George A.
Published: March 2009

Intraperitoneal injections of des Gly10-(D-Ala6) luteinizing hormone-releasing hormone ethylamide (LH-RHA DAla6) alone and in combination with partially purified chinook salmon gonadotropin (SG-G100) were shown to be highly effective means of inducing ovulation in coho salmon. Two injections of LH-RHA DAla6 72 h apart or LH-RHA DAla6 injected with or 72 h following an injection of SG-G100 induced ovulation in 6–10 days. The induction of ovulation was associated with the duration rather than the initial magnitude of the increase in plasma gonadotropin levels. Plasma 17β-estradiol levels decreased whereas plasma 17α,20β-dihydroxy-4-pregnen-3-one (17α20βP) levels increased in response to elevated plasma gonadotropin levels. The time of ovulation was related to the magnitude and rate of change in plasma 17β-estradiol and 17α20βP levels. Ovulation occurred following a reduction of plasma 17β-estradiol levels to less than 2 ng/mL and this decline preceded or was concomitant with an increase in plasma 17αt20βP levels to 450–500 ng/mL. 17α20βP levels in fish which underwent oocyte maturation but not ovulation were lower (100 ng/mL), suggesting that high levels of 17α20βP may have a direct role in ovulation. Changes in 17β-estradiol production appear to determine the time of ovulation by influencing the magnitude and rate of increase of plasma 17α20βP levels.
Weight loss of spruce grouse eggs during incubation
Authors: Keppie Daniel M.
Published: March 2009

Rates of weight loss were calculated for eggs incubated by spruce grouse (Dendragapus canadensis) during 1977 to 1984 in New Brunswick. The mean rate of weight loss was 0.18 g/d during the first 20 days of incubation. Rates of loss differed among clutches, were greater for eggs of adult versus yearling females, and were greater for large than for small eggs. Variances of egg volume indices were greater among than within clutches, but volumes did not differ among eggs of adult versus yearling females. Enough variation occurred in rates of weight loss that they cannot be used to predict the ages of eggs (number of days into incubation).
Food habits of the northern flying squirrel (Glaucomys sabrinus) in Oregon
Authors: Maser Zane , Maser Chris , Trappe James M.
Published: March 2009

Digestive tracts of 91 northern flying squirrels (Glaucomys sabrinus) were analyzed for food items; 28 were from northwestern Oregon and 63 from northeastern Oregon. Ninety percent or more of the ingested materials were fungi and lichens, including 20 genera of hypogeous fungi. The northern flying squirrel, in using hypogeous fungi as a major food source, is an important nocturnal disperser of the spores. In Oregon coniferous forests, these fungi are obligatory ectomycorrhizal symbionts with the trees in which the squirrels live.
Analysis of temporal variation in the diversity of a small mammal community
Authors: Asher S. C. , Thomas V. G.
Published: March 2009

The validity of using single-sample surveys to measure small mammal diversity was assessed by measuring the effect of short-term, temporal variation in species diversity on the spatial diversity of small mammals occupying fencerow habitats. The diversity of small mammals varied seasonally. Interaction between changes in richness and evenness accounted for the temporal variation in diversity. Temporal variation was attributed to the response of the small mammals to seasonal changes in the vegetation, to the fluctuation in meadow vole (Microtus pennsylvanicus) captures among seasons, and to the appearance of small numbers of several mammal species during the summer. Significant spatial variation in species diversity existed, but was masked by the effect of seasonal changes in habitat on the small mammals. Erroneous conclusions could therefore be drawn from the pooling of many single-sample surveys of small mammal diversity.
The effects of different doses of pimozide and [D-Ala6, Pro9-N ethylamide]-LHRH (LHRH-A) on gonadotropin release and ovulation in female goldfish
Authors: Sokolowska M. , Peter R. E. , Nahorniak C. S.
Published: March 2009

Female goldfish, in late stages of ovarian recrudescence, held at 12 or 20 °C, were injected with a range of dosages of the dopamine antagonist pimozide, at 10, 1, and 0.1 μg/g body weight, to block the endogenous gonadotropin release inhibitory activity of dopamine, and 3 h later were injected with [D-Ala6, Pro9-N ethylamide]-luteinizing hormone-releasing hormone (LHRH-A), at 0.1 μg/g body weight, after which serum gonadotropin levels were determined. The results demonstrate the dose dependency of pimozide in potentiating the activity of LHRH-A. In a second set of experiments, using female goldfish in a preovulatory condition, held at 12 and 20 °C, the changes in serum gonadotropin levels and frequency of ovulation were determined following injection of pimozide, at 1 μg/g body weight, and LHRH-A, at 0.1, 0.01, and 0.001 μg/g body weight. The results demonstrate that pimozide potentiates a dose-dependent response to LHRH-A. The maximum serum GtH levels found in response to the same dosages of pimozide and LHRH-A at 12 and 20 °C were similar; however, the maximum levels occurred earlier at 20 °C (6 h postinjections) than at 12 °C (24 h postinjections). Notably, only the combination of pimozide at 1 μg/g body weight and LHRH-A at 0.1 μg/g body weight, in fish at 20 °C, was highly effective in inducing ovulation.
Avian Haemoproteidae. 19. The haemoproteids of the sunbirds (family Nectariniidae) and morphometric variation in Haemoproteus sequeirae
Authors: Bennett Gordon F. , Peirce Michael A. , Caines Jennifer R.
Published: March 2009

The haemoproteids of the sunbird family Nectariniidae are reviewed on the basis of material obtained from throughout the distributional range of the family. Variability in the 19 morphometric parameters used to define haemoproteid species were studied (i) over time in the same individual host; (ii) between individual hosts of the same species; (iii) between hosts of different species; and (iv) between hosts from different geographic regions. Statistical analyses indicated that the morphology of the parasites remained remarkably constant and the degree of variability noted was of the same order of magnitude for parasites within a single smear, between individual and different species of hosts, and between hosts from different regions. All parasites studied were morphologically similar and represented a single species, Haemoproteus sequeirae Tendeiro, 1947. Haemoproteus raymundi de Mello and Raimundo, 1934, is declared incertae sedis.
The effect of temperature on rates of development of larval Protostrongylus spp. (Nematoda: Metastrongyloidea) from bighorn sheep, Ovis canadensis canadensis, in the snail Vallonia pulchella
Authors: Samson J. , Holmes J. C.
Published: March 2009

The rate of development of Protostrongylus stilesi and (or) Protostrongylus rushi in the intermediate host Vallonia pulchella was related linearly to temperature between 10 and 30 °C. The temperature threshold was 8 °C and the thermal constant was 305 degree-days. Infected snails kept at 10 °C for several days and then transferred to 25 °C produced third-stage larvae faster than expected. Rates of development of Protostrongylus spp. applied to field conditions indicated that most of the first- to third-stage development occurs during the summer, very slow development takes place in the autumn or the spring, and none occurs over the winter. These data reinforce the hypothesis formulated by D. A. Boag and W. D. Wishart that snails on the bighorn sheep wintering grounds are responsible for transmission of the lungworms to sheep in autumn.
An observation of possible cannibalism by polar bears (Ursus maritimus)
Authors: Lunn N. J. , Stenhouse G. B.
Published: March 2009

We observed a case of cannibalism by a 23-year-old adult male polar bear in very poor physical condition on Southampton Island, N.W.T. It had apparently killed an adult female and was feeding on the carcass. Cannibalism among polar bears does occur under natural conditions. It is difficult to document how often this occurs and of what ecological significance it might be.
Revision of the genus Sciadiocara Skrjabin, 1916 (Nematoda: Acuarioidea)
Authors: Wong P. L. , Lankester M. W.
Published: March 2009

The genus Sciadiocara Skrjabin, 1916 is revised and the following species are recognized: Sciadiocara umbellifera (Molin, 1860); Sciadiocara bihamata (Mueller, 1897) with Sciadiocara denticulata Gibson, 1972 as its new synonym; Sciadiocara legendrei Petter, 1967; Sciadiocara serrata Wang, 1966; Sciadiocara cucullatus (Wehr, 1934); Sciadiocara chabaudi Schmidt and Kinsella, 1972; and Sciadiocara rugosa Schmidt and Kinsella, 1972. Sciadiocara secunda Skrjabin, 1916 is considered a nomen nudum. All species except S. legendrei and S. serrata are redescribed.
Revision of the genus Sobolevicephalus Parukhin, 1964 (Nematoda: Acuarioidea)
Authors: Wong P. L. , Lankester M. W.
Published: March 2009

Sobolevicephalus Parukhin, 1964 is revised and Sobolevicephalus chalcyonis Parukhin, 1964, Sobolevicephalus madagascariensis (Kung, 1948) n. comb., and Sobolevicephalus lichtenfelsi n. sp. are recognized. Sobolevicephalus chalcyonis is redescribed and S. lichtenfelsi is described.
Effect of host on the oviposition and development and survival of the larvae of Aulacophora foveicollis Lucas (Chrysomelidae, Coleoptera)
Authors: Alikhan M. A. , Yousuf M.
Published: March 2009

The development and mortality of the larvae of Aulacophora foveicollis reared on flowers and leaves of Citrullus vulgaris, Cucumis melo, Lagenaria vulgaris, Luffa aegyptica and Momordica charantia, were investigated in the laboratory at 21.5 °C and 52 – 60% relative humidity. Aulacophora foveicollis had four larval instars and its growth curve on L. vulgaris was S-shaped. The number of viable eggs and the survival of the larvae were relatively high on L. vulgaris, C. melo, and C. vulgaris. The larval developmental time was similar and the percentage of malformed adults was low on L. vulgaris and C. melo. The number of viable eggs was the lowest and the newly hatched larvae were unable to survive for more than 3 days on M. charantia.
Foraging behaviour and food habits of Stone's sheep
Authors: Seip Dale R. , Bunnell Fred L.
Published: March 2009

Foraging behaviour of Stone's sheep (Ovis dalli stonei) was compared between different times of the year and between burned and unburned ranges. Seasonal habitat selection resulted in the sheep feeding on the ranges which provided the highest quality available forage. In winter, snow severely restricted the area that provided available forage. Sheep fed primarily on grasses, although forbs and browse were also important foods in the spring and summer. Plant species selected by the sheep in summer were not higher in protein or lower in acid detergent fiber than avoided species, but rather lacked the physical and chemical deterrents present in avoided plants. Intake rate (estimated from biting rate of ewes and foraging time) appeared to be independent of herbage quantity on spring ranges.
Variation in acid tolerance of Connecticut wood frogs: genetic and maternal effects
Authors: Pierce Benjamin A. , Sikand Nalin
Published: March 2009

Acid tolerance in wood frog (Rana sylvatica) embryos and larvae was examined in full- and half-sib families. Among the embryos, no significant difference in acid tolerance at pH 3.75 was observed among the progeny of males. At pH 4 only slight differences in embryo acid tolerance existed among the progeny of males mated to the same female. Thus, there is relatively little direct genetic variation in embryo acid tolerance. However, progeny from different females differed significantly in their acid tolerance at both pH 4 and pH 3.75, indicating that maternal factors are important in embryo acid tolerance. Whether these maternal factors are genetic is not known. Among larvae, maternal factors did not appear to influence acid tolerance, but significant genetic variation was present. Larval survival in an acidic solution was not correlated with embryo acid tolerance.
Description of Rhabditis (Pellioditis) dolichuroides n. sp. (Nematoda: Rhabditidae) from Kenya
Authors: Anderson R. V. , Sudhaus W.
Published: March 2009

A new bisexual species of the Rhabditis (Pellioditis) dolichura-group, associated with a scarabaeid beetle larva, is described and illustrated. Distinguishing features of the female are metastomal teeth, a body length of over 1000 μm, an attenuated conoid tail at least 120 μm long, and a rectum 41 – 66 μm long. Characters of the male include a body length of at least 1045 μm, and spicule and gubernaculum lengths of 41 – 48 μm, and 22 – 29 μm, respectively. A large dorsorectal glandular complex of variable size and granular content has been identified and is thought to have a secretory function.
Intra- and inter-specific mitochondrial DNA sequence divergence in Salmo: rainbow, steelhead, and cutthroat trouts
Authors: Wilson Gary M. , Thomas W. Kelley , Beckenbach Andrew T.
Published: March 2009

Two forms of Salmo gairdneh with different life histories (steelhead and rainbow trout) were compared using restriction endonuclease analysis of mitochondrial DNA. A total of 19 individuals from four populations were studied for each of the two forms, using 14 restriction enzymes. In addition, five cutthroat trout samples were included as an interspecific comparison. These enzymes revealed a total of 81 cut sites, representing a sample of more than 400 nucleotides per fish. Of these sites, 25 were phylogenetically informative, dividing the 43 fish into 10 clonal lines, 8 Salmo gairdneri and 2 Salmo clarki. Results indicated detectable divergence between all geographic populations of steelhead and rainbow trout except Pennask rainbow trout, Coquihalla steelhead, and Wampus Creek rainbow trout. Other steelhead populations analysed showed a closer phylogenetic relationship to each other than to rainbow trout populations analysed. Intraspecific divergence was in most cases 1% or less, with a 1.5% maximum. Interspecific divergence between S. gairdneri and S. clarki was between 2% and 3.5%.
Maneuverability of the Humboldt penguin (Spheniscus humboldti) during swimming
Authors: Hui Clifford A.
Published: March 2009

Analyses of high-speed film of captive Humboldt penguins (Spheniscus humboldti) show that there is no correlation between the radii of submerged turns and swimming speed. The sharpest turns had a mean turn radius (n = 5) of 0.14 m (0.24 body lengths), were powered by beating wings, and used multiple steering structures (beak, tail, feet, wings) and a flexing body. This turn radius is similar to that of fast-swimming fish with rigid bodies and lunate tails but is greater than that of slower fish with flexible bodies. The maximum turning rate was 10.05 radians s−1. Maneuverability is augmented by neck-extending strike behavior and porpoising leaps.
A critique of the concept of genetic assimilation as a mechanism in the evolution of the terrestrial talitrids (amphipoda)
Authors: Duncan Kelvin W.
Published: March 2009

This note is a critique of Matsuda's 1982 paper (R. Matsuda. 1982. Can. J. Zool. 60: 733–749) in which he discussed the mechanisms involved in the evolution of the terrestrial Talitridae or landhoppers.
A critique of the mechanics of annual changes in ptarmigan numbers
Authors: Bergerud A. T. , Mossop D. H. , Myrberget Svein
Published: March 2009

Two hypotheses are evaluated to explain the annual changes in the size of breeding populations of ptarmigan (Lagopus spp.) from one breeding season to the next: H1, fluctuations are caused by density-dependent changes in the mortality of birds 4 months old and older that are excluded by territorial behaviour; and H2, populations fluctuate through annual changes in breeding success during the previous season. In 11 populations reviewed here, changes in the size of breeding populations were positively correlated with the previous season's breeding success. Significant mortality in three populations of birds > 4 months of age occurred during the winter before the birds became spaced on territories in the spring. In 9 of the 11 ptarmigan studies reviewed, sizes of spring populations were linearly correlated with the size of the fall populations the previous year, indicating that little compensatory, density-dependent mortality between the breeding seasons, a test implication of the territorial hypothesis (H1), had occurred. The data presented and reviewed suggest that changes in breeding success are sufficient to explain the dynamics in population size. Territorial behaviour appears to be a breeding tactic to space birds relative to environmental requisites, as argued by D. Lack, and does not result in significant numbers of nonterritorial, surplus birds with short life expectancies.
The use of growth curves to assess the crowding effect on procercoids of the tapeworm Triaenophorus crassus in the copepod host Cyclops bicuspidatus thomasi
Authors: Shostak Allen W. , Rosen Ronald B. , Dick Terry A.
Published: March 2009

Richards growth curves were fitted to data from procercoids of Triaenophorus crassus (Pseudophyllidea) in experimentally infected Cyclops bicuspidatus thomasi (Copepoda). Average volume per procercoid varied inversely with intensity, and procercoids in female copepods were correspondingly larger than procercoids in males. The simple inverse relationship, which usually characterizes the crowding effect on cestode size, held for average procercoid growth rates, but the growth rates of differentiated and undifferentiated procercoids diverged at higher intensities. Three apparently intrinsic features of procercoid growth (initiation of differentiation at a fixed time, a minimum size threshold for differentiation, and an accelerated growth rate in procercoids following differentiation) provided a mechanism whereby natural variation in procercoid growth rates could be amplified to produce a parasite infrapopulation comprising large, differentiated procercoids and stunted, undifferentiated procercoids. Calculations using parameters of the fitted growth curves indicated that the hosts were probably under nutritional stress in low intensity infections during rapid growth of the differentiating and differentiated procercoids.
The ultrastructure of the giant cell surrounding larvae of Thelazia spp. (Nematoda: Thelazioidea) in the face fly, Musca autumnalis De Geer
Authors: Stoffolano Jr. John G. , Yin Lucy R. S.
Published: March 2009

The larval nematode, Thelazia spp., initiates a tissue response by the body-wall epidermal cells of its normal intermediate host, Musca autumnalis, resulting in the formation of giant cells. These giant cells differ in several ways from hemocytic capsules: they are larger, lack signs of necrosis, protect the parasite, and represent a true syncytium. Both, however, are considered to be the result of a defensive reaction by the host. Giant cells contain the following organelles which are absent from hemocytic capsules: hypertrophied nuclei, smooth-surfaced endoplasmic reticulum, and annulate lamellae. Further, unlike hemocytic capsules, giant cells lack cell junctions and cytolysosomes. Formation of giant cells is considered beneficial to both the host and the parasite.
Four new species of water mite in the subgenus Arrenurus from North America (Acari: Hydrachnellae: Arrenuridae)
Authors: Conroy J. C.
Published: March 2009

Four new species (Arrenurus galweyensis, A. haywardensis, A. fredi, and A. paracascadensis) in the subgenus Arrenurus are described from collections made in Alberta, Canada, and Wisconsin, United States of America.
Behaviour of spruce grouse broods in the field
Authors: Schroeder Michael A. , Boag David A.
Published: March 2009

Behaviour of juvenile spruce grouse (Dendragapus canadensis), from hatching to brood breakup, was observed in 30 radio-tracked broods inhabiting lodgepole pine (Pinus contorta) forests of southwestern Alberta. The immediate posthatch period (first 20 days) was characterized by a close spatial relationship between the chicks and hen, with brooding being the dominant behaviour. Hens with broods appeared to respond immediately, both vocally and through movement toward their chicks, whenever the latter uttered the following calls: sreep, sury, seer, and purring. Brooding sessions decreased in frequency but not duration (median of 11 min) until they disappeared from the behavioural repertoire of the chicks at about 50 days of age. Hen–chick and intersibling distances increased as the chicks grew older. The breakup of broods appeared to result when the cohesiveness of the brood decreased to a point at which calls of the chicks no longer elicited a response from the brood hen. There was no evidence that agonism contributed to this decline in brood cohesion.
Relationships between group size, feeding time, and agonistic behavior of mountain goats
Authors: Risenhoover Kenneth L. , Bailey James A.
Published: March 2009

Relationships between group size, intragroup spacing, movement rates, foraging behavior, and frequency of agonistic behavior of mountain goats (Oreamnos americanus) using alpine tundra were examined during summer. Feeding time of goats increased with group size to about 12 goats because of a reduction in time devoted to alert behavior. Rates of movement by foraging goats increased with group size, whereas rates of agonistic behavior between goats declined with increased group size. Intragroup spacing declined as group size increased. Nannies and 2-year-old goats were more aggressive than were other sex- or age-classes. Two-year-old goats, yearlings, and billies received more threatening displays than did other classes. In Colorado, nannies with kids form large nursery bands on alpine tundra. This behavior can reduce the risk of predation to individuals while allowing nannies with kids to exploit forage away from precipitous terrain. Average group size may be a useful index to forage abundance and continuity on summer goat range.
Manipulation of aggressive behavior in male prairie voles (Microtus ochrogaster) implanted with testosterone in Silastic tubing
Authors: Gaines M. S. , Fugate C. L. , Johnson M. L. , Johnson D. C. , Hisey J. R. , Quadagno D. M.
Published: March 2009

Subadult male prairie voles were implanted with testosterone in Silastic tubing in an attempt to manipulate aggressive behavior. The implanted voles exhibited a higher level of aggression than either controls or shams in pairwise encounters in a neutral arena. Release rates of testosterone from Silastic tubing were measured in castrated males by radioimmunoassay. Serum testosterone titer of each group of castrated males implanted with three different sized capsules rose to a maximum on the 4th day after implantation and declined to a minimum thereafter. Group mean titers declined in the order of their capsule sizes. It was concluded that implants of testosterone in Silastic tubing are an effective method of increasing aggressiveness in male prairie voles. The possible mode of action of testosterone mediated aggression is discussed.
Larval development of a molpadiid holothuroid, Molpadia intermedia (Ludwig, 1894) (Echinodermata)
Authors: McEuen F. Scott , Chia Fu-Shiang
Published: March 2009

Large adults of the caudate molpadiid Molpadia intermedia were collected from soft mud at depths of 26–28 m in East Sound, Orcas Island, Washington. In early December, both sexes spawned in the laboratory: males released occasional puffs of sperm and one female forcefully jetted eggs into the water column. The egg is 267 ± 12 μm in diameter and negatively buoyant with an orangish pink yolky cap at the animal pole which, after fertilization, develops into a coeloblastula through equal, holoblastic cleavages. The doliolaria larva bears two posterior ciliary rings and is uniformly ciliated on the anterior third of its body. The larva takes up a benthic existence soon after formation of the ciliary rings and becomes a pentactula with the protrusion of five primary tentacles. Addition of fine mud to cultures induced metamorphosis, at which time the collar of pink yolk is seen to be transferred to the region of the digestive tract. The larvae can delay metamorphosis for at least 5 d in the absence of mud. The early juvenile is transparent, and spired triradiate ossicles proliferate in the body wall. From this study and from a review of the literature, we suggest that the reproduction of the approximately 85 species of sea cucumbers in this cosmopolitan order is likely to be consistent with what we have described for M. intermedia. It is also suggested that the pink colored yolk can be used as a marker in experimental studies of development.
Reproductive performance of American Kestrels laying replacement clutches
Authors: Bowman Reed , Bird David M.
Published: March 2009

Egg dimensions, nestling growth, and reproductive success were compared between first and second clutch nests of American Kestrels (Falco sparverius) to determine the influence of renesting on fledging success. Eggs were removed from 11 nests during 1982–1983. Eight nests served as controls. Most pairs (81.8%) renested on their original territory. We found no significant differences in egg dimensions, fertility, or hatchability between the two groups. Second clutch males (n = 6 clutches) were smaller at hatching than males from first clutches (n = 8 clutches). By day 24 these males (n = 5 clutches) were heavier, with significantly longer manus and antebrachia than first clutch males (n = 3 clutches). However, five of eight first clutch nests fledged all males before day 24. Males remaining in first clutch nests beyond day 24 were lighter with significantly smaller antebrachia by day 18 than males fledging before day 24. This may have biased our comparisons between first and second clutch males. No significant differences in growth were found between female groups. First-clutch progeny fledged significantly younger than second-clutch birds. Males fledged earlier than females in first clutches, but the sexes fledged simultaneously in second clutches.
The chromosomes of Gryllus field cricket populations in central Chile (Insecta: Grylloptera: Gryllidae)
Authors: Lamborot M. , Alvarez-Sarret E.
Published: March 2009

Samples of Gryllus crickets from 13 localities in central Chile were studied to determine the number and morphology of their chromosomes. The diploid number was found to be 28 autosomes plus XO for males and XX for females. Three populations out of 13 analyzed presented a high percentage of individuals bearing one, two, three, or four supernumerary chromosomes; the B chromosomes are the smallest of the complement. The common karyotype can be arranged into three groups: group A with nine pairs of metacentric chromosomes including the X chromosomes; group B with three pairs of submetacentrics, one of them with a satellite; and group C with three pairs of subtelocentric chromosomes. The diploid numbers reported for this group of populations of Gryllus fit well with those reported for several species of the genus, but great differences exist between the Chilean populations of Gryllus and all other species of the genus previously reported. Minor differences were established when the Chilean populations of Gryllus were compared with those of Gryllus argentinus from Argentina. The importance of the chromosomal differences at the specific level, the existence of the B chromosomes, as well as other chromosomal features are discussed. The name Gryllus fulvipennis Blanchard would seem advisable for the time being until a whole taxonomic revision of neotropical species of the genus is undertaken.
Seasonal changes in habitat use by Maine spruce grouse
Authors: Allan Thomas A.
Published: March 2009

Seasonal change in habitats used by spruce grouse (Dendragapus canadensis) in eastern Maine was studied from spring 1981 until autumn 1983. Forest composition averaged 88 and 90% conifer tree species for males and females, respectively. Red spruce (Picea rubens) and balsam fir (Abies balsamea) were the dominant trees present in all habitats at all seasons. Forest density of habitats used by grouse differed significantly by season and sex. During winter males and females used conifer stands that were denser than random plots. During spring and summer females used sites that were less dense than those used by males and had a more open canopy and more ground vegetation. Both sexes showed seasonal changes in the proportion of time observed in trees. By midsummer, males and nonbrood females exhibited a strong selection for larch (Larix laricina) trees. During autumn both sexes moved to habitats with an increased proportion of larch and were found in these trees greater than 75% of the time Larch needles were considered an important transition food to the winter diet of conifer needles.
Metamorphosis of the sabellariid polychaete Sabellaria cementarium Moore: a histological analysis
Authors: Smith Peter R. , Chia Fu-Shiang
Published: March 2009

The histology of the nectochaeta larva of the polychaete Sabellaria cementarium Moore and its changes during metamorphosis are described. The epidermis of the nectochaeta consists of five types of cells: locomotory, sensory, pigment, gland, and nonciliated. Setal sacs, containing provisional setae and settling paleae, are located on either side of the body. The muscle system consists of circular and longitudinal trunk muscles and a setal sac – esophageal muscle complex. The alimentary tract consists of an esophagus possessing three types of gland cells, a stomach composed of large vacuolated cells anteriorly and squamous cells containing lipid droplets posteriorly, and an intestine. The nervous system is composed of a cerebral ganglion, circumesophageal connectives, subesophageal ganglia, and paired ventral nerve cords. The blood vascular system consists of supraesophageal, lateral esophageal, dorsal and ventral blood vessels, and dorsal and ventral blood sinuses. Mucous glands are present in the episphere and pygidium and five types of gland cells are found in the parathoracic region. Metamorphosis of the nectochaeta into a sedentary, benthic juvenile involves the following morphological changes: atrophy of prototrochal cells, loss of provisional setae and regional histolysis within the setal sacs, loss of epispheral and pygidial mucous glands, discharge of parathoracic glands that form the mucoid tube, formation of a head coelom, enlargement of cerebral ganglion, histolysis of the setal sac – esophageal muscle complex, and hypertrophy and dissociation of the vacuolated stomach cells.
The effect of time of day and photoperiod on prolactin content and electrophoretic mobility in the pituitary of the goldfish, Carassius auratus L.
Authors: Knight Gordon C. , Sage Martin
Published: March 2009

Prolactin was identified in goldfish pituitaries by its location within the pituitary, the absence of carbohydrate, its cross reactivity with antiovine prolactin, and its molecular weight. The optimal conditions for the separation of goldfish pituitary prolactin by disc electrophoresis were determined. On a long photoperiod (10L:14D) prolactin showed two peaks of concentration: a lesser one early in the dark phase, followed by a major one at the end of the dark phase. On a short photoperiod (10L:14D) a single peak occurred early in the dark phase. The electrophoretic mobility of prolactin varied diurnally and with change in photoperiod. Mobility was greatest when pituitary content of prolactin was least and vice versa. Evidence is presented that the change in mobility reflects changes in the prolactin molecule and is not an artifact induced by varying protein concentration or other variables in the electrophoretic technique.
Body composition of white-tailed deer estimated by deuterium oxide dilution
Authors: Rumpler W. V. , Allen M. E. , Ullrey D. E. , Earle R. D. , Schmitt S. M. , Cooley T. M.
Published: March 2009

Nine nonpregnant, female white-tailed deer (Odocoileus virginianus), 2 to 4 years of age, were used to determine whether body composition can be estimated from deuterium oxide dilution in body water. Venous blood was collected at 0, 20, 30, 40, 50, 60, 80, 120, 240, and 480 min and at 24 and 48 h after deuterium oxide infusion. The deer were then killed and analyzed for dry matter, crude protein, ether extract, and ash. Deuterium oxide dilution, extrapolated to zero time, overestimated analyzed body water by 6%, but the two measures were highly correlated (r2 = 0.85). Incorporation of live weight with estimated body water in the prediction equation increased r2 to 0.95. Ingesta-free body crude protein and ether extract were highly predictable (r2 = 0.92 and 0.96, respectively) from live weight (WT) and estimated total body water (ETBW). The prediction equation for ingesta-free body ether extract was EE = −7.520 + 0.6110(WT) – 0.5417(ETBW), with all measures expressed in kilograms. When ETBW was determined from deuterium oxide dilution in a single 2-h postinfusion blood sample, the prediction equation for ingesta-free body ether extract was EE = −6.306 + 0.6977(WT) – 0.6870(ETBW) (r2 = 0.94).
Acanthochondria hippoglossi sp.nov. (Copepoda, Chondracanthidae), a crustacean parasite of some flatfishes off the Pacific coast of North America
Authors: Kabata Z.
Published: March 2009

The female of Acanthochondria hippoglossi sp.nov. is described from the flatfishes Hippoglossus stenolepis and Hippoglossoides elassodon, taken off the shores of British Columbia. The confusion existing in the literature between this species and Acanthochondria cornuta is discussed and the presence of the latter species in the Pacific discounted.
Low temperature regulation of antifreeze glycopeptide levels in Atlantic cod (Gadus morhua)
Authors: Fletcher Garth L. , King Madonna J. , Kao Ming H.
Published: March 2009

The influence of water temperature and photoperiod on the timing of the annual cycle of plasma antifreeze glycoproteins (AFGP) was examined in Atlantic cod. Long day lengths (18 h) or continuous light had no effect on the time of appearance or disappearance of AFGP from the plasma. Cold water (0 °C) advanced the time of AFGP appearance by as much as 100 days. Long day lengths had no effect on this early induction of AFGP production. AFGP was not detectable in the plasma of fish exposed to water temperatures greater than 1 °C. Although small amounts of AFGP did appear in the plasma of cod exposed to 1 °C, it immediately began to disappear while plasma levels in normal and 0 °C acclimated cod continued to rise. The biological half time of AFGP activity was very sensitive to temperature, ranging from 15.6 days at 5 °C to 99.4 days at 0 °C. The results of this study suggest that the appearance of AFGP in cod during the winter months is dependent on the cod's exposure to water temperatures at least as low as 1 °C. Although 1 °C appears to be capable of initiating production of AFGP, it is not low enough to allow normal protective levels to be built up in the plasma.
Behavioural responses of Common Puffins to kleptoparasitism by Herring Gulls
Authors: Rice Jake
Published: March 2009

Herring Gulls (Larus argentatus) varied their rates of kleptoparasitic attack depending on Common Puffin (Fratercula arctica) foraging success. Attacks were more frequent on days when many puffins brought back food. However, puffins also varied their behaviour when approaching nest sites with food, so the rate of food loss to gulls per puffin remained constant as the number of puffins with food increased. Site differences in puffin activities after landing reflected only direct consequences of puffin and gull abundances and slope topography. After chick provisioning commenced, puffins at all sites showed increased vigilance after landing and more rapid burrow entries. Behaviour of puffins when approaching the slopes showed adaptations to the presence of gulls. On days when many puffins had food, puffins in areas of high gull density swamped the kleptoparasite. On days when few had food, puffins approached the slopes much as they did before chick provisioning commenced. Hosts as well as kleptoparasites may show closely tuned adaptations to potential food supply and likelihood of attacks.
The respiratory behaviour of an air-breathing catfish, Clarias macrocephalus (Clariidae)
Authors: Bevan David J. , Kramer Donald L.
Published: March 2009

Clarias macrocephalus are continuous, facultative air breathers. Individuals (7.6–20.9 g) survived more than 25 days in normoxic water without surface access. Buoyancy decreased and water-breathing frequency increased when surface access was denied, but growth rate and the frequency of air-breathing attempts did not change. We examined air-breathing and water-breathing frequency in shallow (60 cm) and deep (235 cm) water under normoxic (8.0 mg O2∙L−1) and hypoxic (0.3, 0.7, 1.2, and 2.0 mg O2∙L−1) conditions to examine how changes in the travel costs of breathing affected the use of each respiratory mode. Air-breathing and water-breathing frequency increased as dissolved oxygen decreased from 8.0 to 2.0 mg O2∙L−1. Below this level air breathing continued to increase, but water breathing dropped sharply. At higher levels of dissolved oxygen (8.0 and 2.0 mg O2∙L−1), fish in deep water had lower air-breathing and higher water-breathing frequencies than fish in shallow water. Vertical distance travelled and time spent in air breathing increased with increasing depth and with decreasing level of dissolved oxygen. These results support the hypotheses that travel is a significant cost of aerial respiration and that fish respond to increases in this cost by decreasing their use of atmospheric oxygen when dissolved oxygen concentration permits them to do so.
The next 25 years: invertebrate systematics
Authors: Scudder G. G. E.
Published: March 2009

A distinction is made between classification, taxonomy, and systematics. Taxonomic studies in most invertebrate groups will not progress beyond the descriptive stages because of the large number of species to be described, the low profile of taxonomy, and the lack of support for museums. Taxonomy and classification must be seen as immediate economic components of modern biology: systematics should be revived in the universities. The limitations of the morphospecies concept make studies on living forms, freshly killed animals, or specially preserved specimens imperative, but these cannot be completed except in very few instances. Hence we are likely to learn more and more about less and less. Nevertheless, more sibling species complexes will undoubtedly be discovered. When these complexes are understood systematically, and population genetics becomes integrated with the study of speciation, more emphasis will likely be given to the multiplicity of speciation models. A pleuralistic definition of species should follow. Cladistic systematics will continue to expand in the invertebrates. More emphasis should be placed on early Metazoan fossils, and attempts made to fit them into classifications. Fossils can be useful in checking various phylogenetic models, even if they are considered useless for determining evolutionary relationships by some cladists. With the current acceptance that the Protista and Protozoa are both polyphyletic, there will be a major revolution in invertebrate systematics. Ultrastructural and biochemical data are needed to clarify the systematics of both the unicellular eukaryotes and multicellular Metazoa. Only after systematic analyses of wider data sets are complete will it be time to consider a new classification for the "invertebrates." However, the resulting scheme will be very different from that which we accept, follow, and teach today.
Projected research trends in invertebrate physiology and biochemistry
Authors: Downer Roger G. H.
Published: March 2009

The direction of future research is likely to be influenced by major conceptual advances and technological breakthroughs, neither of which can be predicted with certainty. However, it is possible to identify general areas in which conceptual advances may be anticipated as a result of studies on invertebrate physiology and biochemistry and, in this regard, neurobiology and developmental biology offer particular promise. It is reasonable to predict also that the technologies of modern molecular biology and the development of highly sensitive analytical instrumentation will greatly facilitate research progress. Increased activity may also be predicted in strategic research areas including those that will lead to the rational design of pesticides and the improvement of "farming" procedures for invertebrate species that are used as sources of food. Invertebrates are also expected to continue to be used as models for biomedical research.
Song learning in the wood thrush
Authors: Whitney Carl L. , Miller Joan
Published: March 2009

A typical wood thrush (Hylocichla mustelina) song has three phrases. The first (A) is a series of low pitched sounds, the second (B) consists of loud flutelike notes, and the third (C) is usually a trill. Males have repertoires of two to eight different B phrases, which they use in different songs. In a previous study, males reared in isolation of adult song developed songs that were normal except for the structure of the B phrases. We tutored young males (at age 20–80 days) with recorded B phrases. The phrases were of four previously defined structural types, with four variants of each type, giving a total of 16 phrases. The variants of each type differed only in frequency (Hz). The objectives of the experiment were to determine (i) if wood thrushes copy the structure of B phrases that they hear as juveniles, and (ii) if they copy selectively in such a way as to develop repertoires of highly contrasting phrases. Results were obtained for five males. The B phrase repertoires developed by four subjects consisted entirely of phrases (N = 17) copied from the tutor tape. The repertoire of the fifth subject was of phrases (N = 4) that appeared not to be copied. The males that copied from the tutor tape showed no tendency to develop repertoires of highly contrasting B phrases. Three of the four males developed multiple versions of one or more phrase types, while ignoring other types, and in some cases these versions were very similar in frequency and other details of structure.
Differential effects of diurnal and continuous illumination regimes on melanophores and xanthophores of winter flounder, Pseudopleuronectes americanus
Authors: Burton D.
Published: March 2009

The melanophores and xanthophores of Pseudopleuronectes americanus display different adaptive capacities to a white background under continuous (1 week) illumination compared with an equivalent period under diurnal, alternating light (12 h) and dark (12 h) photoperiods. Under the repeated diurnal photocycles on white, melanosomes partly disperse during dark photoperiods, but there is cumulative melanosome aggregation during successive light photoperiods that is interpreted as a slow physiological summation. Consequently, there is no significant difference in the final degree of aggregation attained on a white background on completion of either illumination protocol. In contrast, xanthosomes attain a high degree of aggregation during white background adaptation under continuous illumination, but do not display slow "summation" of pigment aggregation in response to the diurnal light photoperiods. The differences between melanosome and xanthosome aggregation under these photoperiod regimes are discussed in relation to the previously established types of balance between neural and humoral systems controlling flounder melanophores and xanthophores.
Ovulation and placentation in Botryllus schlosseri (Ascidiacea): an ultrastructural study
Authors: Zaniolo Giovanna , Burighel Paolo , Martinucci Gianbruno
Published: March 2009

The mode of ovulation and placentation was studied by light and electron microscopy in the ovoviviparous ascidian Botryllus schlosseri using colonies from the laboratory. The full-grown oocyte is surrounded by the outer and inner follicle cell layers, the acellular vitelline coat (chorion), and the test cells, and it is furnished with its own vesicular oviduct which is interposed between the egg and the atrial epithelium. In contrast to most ascidians, the outer follicle is thick and has an ultrastructure consistent with intense protein synthesis. At ovulation the outer follicle shows signs of involution where it contacts the oviduct. When the oviducal wall breaks and the egg moves through the oviduct, the outer follicle cells are discharged in the mantle to form a sort of corpus luteum. The egg remains hanging in the atrial chamber by means of a cuplike "placenta." The placental tissues are all of maternal origin, being derived from both the atrial and oviducal epithelia together with some of the inner follicle cells. These latter anchor to the oviducal epithelium by means of junctional spots and a filamentous cementing secretion. Our results suggest that the main role of the "placenta" is to attach the embryo to the parent, thus exposing it to the flow of seawater.
Spectral transmittance of the ocular media of the bluegill (Lepomis macrochirus)
Authors: Chou B. Ralph , Hawryshyn Craig W.
Published: March 2009

The spectral transmittance of bluegill (Lepomis macrochirus) ocular media (n = 10 eyes) was measured over the wave band 310 to 750 nm, using a specially modified spectrophotometer. Transmittance was approximately uniform at 0.92 between 450 and 750 nm, fell to < 0.5 by 400 nm, and to 0.01 by 370 nm. The ocular media minimize exposure of the retina to potentially harmful shortwave ultraviolet radiation. The adaptive significance of such a preretinal filter in this teleost is briefly discussed.
Reproductive success and growth of two species of Erpobdellidae: the effect of water temperature
Authors: Wrona Frederick J. , Linton L. R. , Davies Ronald W.
Published: March 2009

Cocoon production and hatchling growth of two species of Erpobdellidae (Nephelopsis obscura and Erpobdella punctata) were compared at different water temperatures (5–20 °C). Based on the mean number of cocoons produced per individual, mean numbers of eggs per cocoon, cocoon hatching success, and hatchling growth rates, E. punctata has an ecological advantage over N. obscura at 5 and 10 °C. At 15 and 20 °C, neither species displayed a clear advantage over the other in relation to production or growth of offspring. It is suggested that the observed interspecific differences may at least in part explain the numerical dominance of E. punctata in colder lotic ecosystems.