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Heeding warnings from the canary, the whale, and the Inuit.

There is a tension between traditional and modern definitions of reproductive risk and normalcy. This excerpt describes that tension as it plays out among the Inuit of Northern Canada from the perspective of a community midwife who has worked with the Inuit. She presents an analytical framework which classifies and illuminates the types of logic that compete in most birth settings around the world-a framework useful for showing how some types of logic can be supervalued while others, such as cultural or intuitive logic, are devalued or simply ignored, often at great cost. The forced evacuation of all pregnant Inuit women from Northern Canada for the "privilege" of a hospital birth in the South illustrates the imbalance created when decisions purported to be based on one kind of logic (scientific) are in reality based on another (e.g., legal and clinical), or when any type of logic is given undue authority. After presenting the analytical framework and describing some of the history of Inuit childbirth, the author tells the story of one Inuit settlement's attempt to re-integrate the authoritative knowledge of the community by allowing Inuit midwives to choose their own criteria for balancing the imperatives of each kind of logic in decision-making for birth.

Adolescent↗

[Appearance of the flutter on surface of the body of whale-like dolphins].

In the article a problem of the flow near of elastic surface body whalelike is considered. The opportunity appearance of the flutter on a surface body is shown. Additional capacity, necessary dolphin is designed at navigation in case of occurrence the flutter. It is shown, that this capacity makes about 26% of limiting capacity, output dolphin. Number Relcr = 4,4.10(6) transition to flutter's mode of the flow the body of the dolphin is found. It is discussed evolutionary formed the mechanism of antiflutter stabilization of the body.

Animals↗

Heeding warnings ... from the canary, the whale, and the Jnuit, Part Two.

There is a tension between traditional and modern definitions of reproductive risk and normalcy. These experts describe that tension as it plays out among the Inuit of Northern Canada from the perspective of a community midwife who has worked with the Inuit. She presents an analytical framework which classifies and illuminates the types of logic that compete in most birth settings around the world--a framework useful for showing how some types of logic can be supervalued while others, such as cultural or intuitive logic, are devalued or simply ignored, often at great cost. Part One presented political, scientific, clinical and cultural logic, and the influence of time. We now go on to look at professionalization and training and describe legal, personal, intuitive and economic logic. The author describes how the Inuit settlement of Povungnituk (POV) attempts to re-integrate the authoritative knowledge of the community by allowing Inuit midwives at The Maternity to choose their own criteria for balancing the imperatives of each kind of logic in decision-making for birth.

Canada↗

Marine mammal strandings in the New Caledonia region, Southwest Pacific.

Four hundred twenty three marine mammals, in 72 stranding events, were recorded between 1877 and 2005 in New Caledonia, the Loyalty Islands, and Vanuatu in the southwest Pacific. Sixteen species were represented in this count, including: minke whale, Balaenoptera acutorostrata (1 single stranding), sei whale, B. borealis (1 single stranding), blue whale, B. musculus (1 single stranding), humpback whale, Megaptera novaeangliae (2 single strandings), giant sperm whale, Physeter macrocephalus (18 single strandings, 2 pair strandings), pygmy sperm whale, Kogia breviceps (5 single strandings), dwarf sperm whale, K. sima (2 single strandings, 1 triple stranding), Blainville's beaked whale, Mesoplodon densirostris (2 single strandings), short-finned pilot whale, Globicephala macrorhynchus (4 strandings, 56 individuals), melon-headed whale, Peponocephala electra (1 single stranding and 2 mass strandings totalling 231 individuals), common dolphin, Delphinus delphis (1 single stranding), spinner dolphin, Stenella longirostris (1 pair stranding and 2 mass strandings of groups of approximately 30 individuals each), Indian Ocean bottlenose dolphin, Tursiops aduncus (2 single strandings), dugong, Dugong dugon (14 single strandings), and New Zealand fur seal, Arctocephalus forsteri (3 single strandings). A stranded rorqual identified as an Antarctic minke whale (B. bonaerensis), with coloration patterns that did not match known descriptions, was also reported. Sei whale was recorded for the first time in the tropical Southwest Pacific region and Antarctic minke whale, melon-headed whale, and Indian Ocean bottlenose dolphin were recorded for the first time in New Caledonia. Strandings of sperm whales were most frequent in the spring, but also occurred in autumn months, suggesting a seasonal pattern of occurrence possibly related to seasonal migration. One stranded humpback whale bore the scars of a killer whale's attack and one dugong was injured by a shark. Scars left by propellers were noted on several stranded animals including one Antarctic minke whale, one pygmy sperm whale, one dwarf sperm whale, and four dugongs. Collisions with vessels were suspected to be a frequent cause of death for dugong.

Animals↗

Phylogeny of all major groups of cetaceans based on DNA sequences from three mitochondrial genes.

Traditionally, living cetaceans (order Cetacea) are classified into two highly distinct suborders: the echolocating toothed whales, Odontoceti, and the filter-feeding baleen whales, Mysticeti. A molecular phylogeny based on 1,352 base pairs of two mitochondrial ribosomal gene segments and the mitochondrial cytochrome b gene for all major groups of cetaceans contradicts this long-accepted taxonomic subdivision. One group of toothed whales, the sperm whales, is more closely related to the morphologically highly divergent baleen whales than to other odontocetes. This finding suggests that the suborder Odontoceti constitutes an unnatural grouping and challenges the conventional scenario of a long, independent evolutionary history of odontocetes and mysticetes. The superfamily Delphinoidea (dolphins, porpoises, and white whales) appears to be monophyletic; the Amazon River dolphin, Inia geoffrensis, is its sister species. This river dolphin is genetically more divergent from the morphologically similar marine dolphins than the sperm whales are from the morphologically dissimilar baleen whales. The phylogenetic relationships among the three families of Delphinoidea remain uncertain, and we suggest that the two cladogenetic events that generated these three clades occurred within a very short period of time. Among the baleen whales, the bowhead is basal, and the gray whale is the sister species to the rorquals (family Balaenopteridae). The phylogenetic position of beaked whales (Ziphioidea) remains weakly supported by molecular data. Based on molecular clock assumptions, the mitochondrial-DNA data suggest a more recent origin of baleen whales (approximately 25 mya) than has been previously assumed (> 40 mya). This revised phylogeny has important implications for the rate and mode of evolution of morphological and physiological innovations in cetaceans.

Animals↗

Temperature regulation of marine mammals.

A mathematical model of heat loss from an aquatic animal to the surrounding water is presented. Heat is generated in metabolically active tissues and distributed by circulating blood and by conduction. The time dependent radial temperature profile of the animal is numerically solved from heat transfer equations by a computer. The model is applied to large whales, porpoises, and seals. For the whales, blood circulation to the dermal layer below appendage and body skin surfaces proved to be essential for sufficient heat dissipation. When decreasing the blood flow below a certain value (dependent on sea temperature and whale activity) the large whales would overheat. Blubber thickness was found to be of minor importance in whale thermoregulation, because the blubber coat can be bypassed by blood circulation. On the other hand, it is in general not possible for small porpoises and seals to stay warm in the coldest waters using normal mammalian resting metabolic rates, even if the peripheral circulation is shut off (or artery-vein heat exchangers used). Heat loss can be reduced if the outermost tissue layers are allowed to cool. This is achieved by minimizing convective radial heat flow via the circulation. (For large whales even minute radial blood flow raises the muscle temperatures to the core temperature level.) Seasonal acclimatization of harbour seals is explained by changes in their effective insulation thickness. Differences in whale activity induce changes in the temperature profile mainly within the first few centimeters from the skin surface. These superficial temperatures, if known, could be used to estimate whale metabolic rates. Since they drop close to the sea water temperature within minutes after whale death, the measurements should be done of live whales.

Animals↗

The limbic lobe of the dolphin brain: a quantitative cytoarchitectonic study.

In these cytoarchitectonic studies of the cortical limbic formations of the bottlenose dolphin and other whale brains we have carried out quantitative analyses of the entire limbic lobe, including all of its sectors: supracallosal, retrosplenial and temporal. The limbic lobe proper has been examined as well as transitional areas between the limbic lobe and the archicortical and paleocortical formations and the extralimbic neocortices, including the entorhinal area and presubiculum. Analyses include total cortical thickness, thickness of individual cortical layers, overall cortical cell densities and glia/neuron ratios, individual laminar counts and glia/neuron ratios and neuron size. Comparisons have been made between these parameters in the brains of the dolphin (Tursiops truncatus), beluga whale (Delphinapterus leucas) and humpback whale (Megaptera novaeangliae). Cortical neuron density values (cells per mm3) in these three species of whales and in the human brain have been compared with similar data given in the literature for elephant, fin whale (Balaenoptera physalus) and human brains. Our values reflect the inverse relationship between brain size and neuron density. Thus, the dolphin shows approximately 13,000 neurons/mm3 in its limbic cortex, compared to 12,000 in the beluga whale and 8,000 in the humpback whale. Further, the data provide the first quantitative accounts on a layer by layer basis of the limbic cortices in the whale brain. In the dolphin, the anterior limbic cortices have a much lower cell density than the posterior limbic area. However, in the humpback whale these two cortices have similar neuron densities. In the temporal region, the entorhinal area is well differentiated into many architectonic subdivisions in the dolphin though not to the extent described in the primate brains. Our findings in the three whale species are discussed in terms of their possible significance and provide quantitative data for future comparative studies with other mammalian species.

Animals↗

Prevalence of Cryptosporidium spp. and Giardia spp. in five marine mammal species.

Cryptosporidium spp. and Giardia spp. are protozoan parasites that are often associated with severe diarrheal disease in a variety of mammals. Although these parasites have been extensively studied in terrestrial ecosystems, little is known about either parasite in the marine environment. Therefore, the objective of this study was to determine the prevalence of both Cryptosporidium spp. and Giardia spp. in 5 marine mammal species. Fecal samples were collected from 39 bowhead whales (Balaena mysticetus), 49 North Atlantic right whales (Eubalaena glacialis), 31 ringed seals (Phoca hispida), 22 bearded seals (Erignathus barbatus), and 18 beluga whales (Delphinapterus leucas) between 1998 and 2003. Using an immunofluorescent assay, parasites were detected in the feces of bowhead whales, right whales, and ringed seals, while neither parasite was detected in samples from bearded seals or beluga whales. Overall, prevalences were highest in ringed seals (Cryptosporidium spp., 22.6%; Giardia spp., 64.5%) and right whales (Cryptosporidium spp., 24.5%; Giardia spp., 71.4%) and lowest in bowhead whales (Cryptosporidium spp., 5.1%; Giardia spp., 33.3%). To our knowledge, this is the first report of Cryptosporidium spp. and Giardia spp. in either whale species and of Cryptosporidium spp. in the ringed seal.

Age Distribution↗

Application of hair-mercury analysis to determine the impact of a seafood advisory.

Following an official recommendation in the Faroe Islands that women should abstain from eating mercury-contaminated pilot whale meat, a survey was carried out to obtain information on dietary habits and hair samples for mercury analysis. A letter was sent to all 1180 women aged 26-30 years who resided within the Faroes, and the women were contacted again 1 year later. A total of 415 women responded to the first letter; the second letter resulted in 145 repeat hair samples and 125 new responses. Questionnaire results showed that Faroese women, on average, consumed whale meat for dinner only once every second month, but the frequency and meal size depended on the availability of whale in the community. The geometric mean hair-mercury concentration at the first survey was higher in districts with available whale than in those without (3.03 vs. 1.88 microg/g; P=0.001). The mercury concentration also depended on the frequency of whale meat dinners and on the consumption of dried whale meat. The 36 women who did not eat whale meat at all had a geometric mean hair-mercury concentration of 1.28 microg/g. At the time of the second survey, the geometric mean had decreased to 1.77 microg/g (P<0.001), although whale was now available in all districts. In comparison with previously published data on hair-mercury concentrations in pregnant Faroese women, these results document substantially lower exposures as well as a further decrease temporally associated with the issue of a stricter dietary advisory.

Adult↗

Relative abundance and behavior of marine mammals exposed to transmissions from the Heard Island Feasibility Test.

The Heard Island Feasibility Test source transmitted a hum at 209-220 dB re: 1 microPa at 175-m depth, centered on 57 Hz with a maximum bandwidth of 30 Hz for 1 h of every 3. Experienced marine mammal observers conducted line-transect surveys and monitored marine mammal behavior visually and acoustically in a 70 x 70 km square centered on the transmission site. Thirty-nine groups of cetaceans and 19 of pinnipeds were sighted from both vessels before the start of transmissions. Thirty-nine groups of cetaceans and 23 of pinnipeds were sighted during transmissions. Blue (Balaenoptera musculus), fin (B. physalus), and sperm (Physeter macrocephalus) whales were sighted during the base line period; blue, sperm, and possibly sei (B. borealis) whales were sighted during the transmission period. More schools of hourglass dolphins (Lagenorhynchus cruciger) were sighted during transmissions, but fewer groups of pilot whales (Globicephala melas), southern bottlenose whales (Hyperoodon planifrons), and minke whales (B. acutorostrata). The density of all cetaceans was 0.0157 groups/km2 before the transmissions and 0.0166 groups/km2 during. Antarctic fur seals (Arctocephalus gazella) and southern elephant seals (Mirounga leonina) were seen, but not in sufficient numbers to estimate abundance. One blue whale tracked before, during and after a transmission changed respiration and reorientation rates, but did not avoid the source detectably. Sperm whales and pilot whales were heard in 23% of 1181 min of baseline acoustic surveys; but in none of 1939 min during the transmission period. Both species were heard within 48 h after the end of the test.

Acoustic Stimulation↗

Systematics of cetaceans using restriction site mapping of mitochondrial DNA.

Phylogenetic analysis of 14 cetacean species, including members from two baleen whale families and three toothed whale families, was undertaken using restriction site mapping of mitochondrial DNA and using cladistic and distance measures to infer phylogenies. The amount of between-taxa sequence divergence inferred from the data was lower than expected from the standard interpretation of the fossil record, but more consistent with some recent estimates of sequence divergence in cetacean mitochondrial DNA or nuclear DNA. This implies either that the rate of molecular evolution of cetacean DNA is much lower than that of other mammalian orders or that the fossil record of cetaceans requires reinterpretation. The incompleteness of the cetacean fossil record precludes resolution of the paradox at the present time. However, this discrepancy could in part be attributed to the sampling error inherent in the restriction site mapping technique, as comparative studies using the complete mtDNA genome and restriction site data of the blue and fin whales (genus Balaenoptera) indicate that the restriction site maps underestimate sequence divergence by about 40%. In contrast to a recent study suggesting that toothed whales were paraphyletic, with the sperm whales being more closely related to the rorquals than to the other toothed whales, the restriction data tend to support the monophyly of the baleen and the toothed whales, a finding which is consistent with a recent molecular-based study and with morphological and paleontological data. Topologies of the subfamily and generic levels are generally consistent with morphologically based schemes.

Animals↗

Effect of marine oils supplementation on coagulation and cellular activation in whole blood.

A study was performed to explore the effects of supplemental intake of various marine oils known to be part of the Eskimo diet. Healthy men and women (134) were randomly selected to consume 15 mL/d of oil from blubber of seal, cod liver, seal/cod liver, blubber of Minke whale, or no oil for ten weeks. Total cholesterol was unchanged in the oil groups, whereas high density lipoprotein cholesterol increased 7% in the seal/cod liver oil (CLO) group (P < 0.05) and 11% in the whale oil group (P < 0.005). Triacylglycerol was significantly reduced in the CLO group only. The concentration of prothrombin fragment 1 + 2 was reduced 25% (P < 0.05) after whale oil supplementation. No change in fibrinogen or factor VIIc was detected. Tumor necrosis factor generation in lipopolysaccharide (LPS)-stimulated blood was 30% reduced after whale oil (P < 0.05), but was unaffected by intake of seal or CLO. The LPS-induced tissue factor activity in monocytes was reduced to a significant degree only in the seal/CLO group (34%) and whale oil group (35%) (P < 0.05). The most dramatic change in thromboxane B2 in LPS-stimulated blood was seen after whale oil intake with 44% reduction (P < 0.01). Supplementation of a regular diet with a combination of seal oil and CLO and especially with whale oil seems to have beneficial effects on several products thought to be associated with cardiovascular and thrombotic diseases.

Adolescent↗

New Zealand's cetaceans and pinnipeds.

The 8 species of baleen whale in New Zealand waters range in length from 6 to 30+ metres, and the 25 species of toothed whale range up to 18 metres. A single porpoise species is known in New Zealand sub-Antarctic waters. The baleen whales and many of the toothed whales are migratory, and New Zealand straddles their well-defined routes: a combination which allowed whaling to flourish. The toothed whales are the more gregarious and may indulge in mass strandings. Current research aims to investigate the biology of all of the whale species. The otariid, or eared seals found in the New Zealand region are the New Zealand sealion and the New Zealand fur seal. The commonest of the phocid, or earless seals on the New Zealand coast are the elephant and leopard seals. All of these breed in the southern parts of the region but range further north. The fur seal population is rising slowly, but the small population size of the New Zealand sealion gives cause for concern. Marine mammals form an important part of the fauna of the New Zealand region, and veterinary knowledge and general research should be increased.

Animals↗

Plasma and urine levels of electrolytes, urea and steroid hormones involved in osmoregulation of cetaceans.

Cetaceans are well adapted to their hyperosmotic environment by properly developed osmoregulatory ability. A question here is how they regulate water and mineral balances in marine habitats. In the present study, we determined blood and urine levels of various chemicals involved in osmoregulation, compared them with those in artiodactyls, and characterized the values in the whales. Blood and urine samples obtained from baleen whales of common minke (Balaenoptera acutorostrata), sei (B. borealis), and Bryde's whales (B. brydei), and toothed whales of sperm whales (Physeter macrocephalus) were analyzed for osmolality, major electrolytes, urea, steroid hormones and glucose. The urine osmolality and Na(+) concentrations in the cetaceans were much higher than those in the cattle. Furthermore, the cetaceans had 5 to 11-fold urea in plasma than the cattle, and 2 to 4-fold urea in urine. There were no significant difference in the plasma concentrations of corticosteroids between the cetaceans and the cattle. The present results indicate that the osmoregulatory parameters seem to be not affected by the reproductive stage and sex steroid hormones. The concentrations of urea in plasma and urine of the baleen whales were higher than those of the sperm whales, indicating a possibility that their osmoregulatory mechanisms may be correlated to their feeding habits. The present results suggest that cetaceans have unique osmoregulatory mechanisms by which they excrete strongly hypertonic urine to maintain fluid homeostasis in marine habitats.

Analysis of Variance↗

Conservation of polymorphic simple sequence loci in cetacean species.

Length polymorphisms within simple-sequence loci occur ubiquitously in non-coding eukaryotic DNA and can be highly informative in the analysis of natural populations. Simple-sequence length polymorphisms (SSLP) in the long-finned pilot whale Globicephala melas (Delphinidae) have provided useful information on the mating system as well as on the genetic structure of populations. We have therefore tested whether the polymerase chain reaction primers designed for Globicephala could also be used to uncover variability in other whale species. Homologous loci could indeed be amplified from a diverse range of whales, including all toothed (Odontoceti) and baleen whales (Mysticeti) tested. Cloning and sequencing these loci from 11 different species revealed an unusually high conservation of sequences flanking the simple-sequence stretches, averaging 3.2% difference over 35-40 Myr. This represents the lowest divergence rate for neutral nucleotide positions found for any species group so far and raises the possible need for a re-evaluation of the age of the modern whales. On the other hand, the high conservation of non-coding sequences in whales simplifies the application of SSLP DNA fingerprinting in cetacean species, as primers designed for one species will often uncover variability in other species.

Animals↗

Identification of sex in cetaceans by multiplexing with three ZFX and ZFY specific primers.

We sequenced 540 nucleotides of the last exon in the ZFY/ZFX gene in two males and two females for eight cetacean species; four odontocetes (toothed whales) and four mysticetes (baleen whales). Based upon the obtained nucleotide sequences, we designed two sets of oligonucleotide primers for specific amplification of the ZFX and the ZFY sequence in odontocetes and mysticetes, respectively. Each primer set consisted of three oligonucleotides; one forward-orientated primer, which anneals to the ZFY as well as the ZFX sequence, and two reverse-orientated primers that anneal to either the ZFX or or the ZFY sequence. The resulting two amplification products (specific for the ZFY and ZFX sequences) can be distinguished by gel-electrophoresis through 2% NuSieve(TM). The accuracy of the technique was tested by determination of gender in 214 individuals of known sex. Finally we applied the technique to determine the sex of 3570 cetacean specimens; 2284 humpback whales, 315 fin whales, 37 blue whales, 7 minke whales, as well as 592 belugas, 335 narwhals and 25 harbour porpoises.

Animals↗

The face that sank the Essex: potential function of the spermaceti organ in aggression.

'Forehead to forehead I meet thee, this third time, Moby Dick!' [Ahab (Melville, 1851)] Herman Melville's fictional portrayal of the sinking of the Pequod was inspired by instances in which large sperm whales sank whaling ships by ramming the ships with their heads. Observations of aggression in species of the four major clades of cetacean and the artiodactyl outgroup suggest that head-butting during male-male aggression is a basal behavior for cetaceans. We hypothesize that the ability of sperm whales to destroy stout wooden ships, 3-5 times their body mass, is a product of specialization for male-male aggression. Specifically, we suggest that the greatly enlarged and derived melon of sperm whales, the spermaceti organ, evolved as a battering ram to injure an opponent. To address this hypothesis, we examined the correlation between relative melon size and the level of sexual dimorphism in body size among cetaceans. We also modeled impacts between two equal-sized sperm whales to determine whether it is physically possible for the spermaceti organ to function as an effective battering ram. We found (i) that the evolution of relative melon size in cetaceans is positively correlated with the evolution of sexual dimorphism in body size and (ii) that the spermaceti organ of a charging sperm whale has enough momentum to seriously injure an opponent. These observations are consistent with the hypothesis that the spermaceti organ has evolved to be a weapon used in male-male aggression.

Aggression↗