Mature female sperm whales (Physeter macrocephalus) live in socially cohesive groups of 10-30, which include immature animals of both sexes, and within which there is communal care of the young. We examined kinship in such groups using analyses of microsatellite DNA, mitochondrial DNA sequence, and sex-linked markers on samples of sloughed skin collected noninvasively from animals in three groups off the coast of Ecuador. Social groups were defined through photographic identification of individuals. Each group contained about 26 members, mostly female (79%6).Relatedness was greater within groups, as compared to between groups. Particular mitochondrial haplotypes were characteristic of groups, but all groups contained more than one haplotype. The data are generally consistent with each group being comprised of several matrilines from which males disperse at about the age of 6 years. There are indications of paternal relatedness among grouped individuals with different mitochondrial haplotypes, suggesting long-term associations between different matrilines.
Summary 0[ This study addresses the issue of structure in sperm whale "Physeter macrocephalus Linnaeus# populations and whether it is geographically based[ 1[ During a survey around the South Paci_c Ocean\ we collected sloughed skin for genetic analyses\ recorded coda vocalizations\ and photographed~uke markings[ 2[ Groups of female and immature sperm whales had characteristic mitochondrial haplotypes\ coda repertoires\ and~uke!mark patterns\ but there was no clear geo! graphical structure in any of these attributes[ 3[ However\ similarities of coda repertoire and mitochondrial haplotype distribution were signi_cantly correlated among pairs of groups in a manner that was not geo! graphically based[ There was also a signi_cant canonical correlation coe.cient between coda repertoire and~uke!mark patterns[ 4[ These results suggest that attributes "such as vocal repertoire and techniques of predator defence# which are acquired matrilineally\ and probably culturally\ are conserved during the _ssion and dispersal of groups[
Five highly variable microsatellite loci were used to investigate population structuring in Pacific herring Clupea pallasi collected from Kodiak Island, two sites in the Bering Sea and four sites within Prince William Sound, Alaska. All loci revealed high levels of variability with heterozygosity estimates ranging from 86 to 97% (mean heterozygosity: 89%). The variation was structured significantly among sites suggesting that the samples investigated were genetically distinct from each other. Genetic divergence was greatest between populations from the Bering Sea and those from Prince William Sound. The Kodiak Island and Point Chalmers samples appeared to be distinct from the Prince William Sound and Bering Sea populations. The observed genetic distance relationships among samples could be explained largely in terms of geographical separation.
This study developed a grounded theory of the stresses and coping responses of parents to the repeated hospitalization of chronically ill and disabled children. The theoretical sampling spanned four years and included 30 mothers of children who have a chronic illness or disability and 30 mothers of healthy children; 100 parents of disabled children who attended a weekend retreat: six community health nurses; nine mothers of chronically ill and disabled children before, during and after a hospitalization. The resulting mid-range theory identifies the most stressful aspect as "hazardous secrets" which force the parent to "reluctantly take charge" of the situation. "Vigilance", "calling a halt", "exhaustion" and "taking a break" are key constructs in the process. "Trusting parent and professional relationships" emerged only when a professional assisted in revealing secrets.
Standardized studies of living sperm whales Physeter macrocephalus were carried out in 3 areas with very different recent whaling intensities. These were off the Galapagos Islands, where there seems to have been little recent whaling, off the Seychelles and Amirantes Islands, where animals were regularly caught by passing Soviet whalers, and off mainland Ecuador, adjacent to the area whaled very heavily from Paita, Peru. Sperm whale densities off the Galapagos were about 4. 2 times higher than off the Seychelles and 2.4 times higher than off mainland Ecuador. Feeding success, as indicated by defecation rates, was significantly higher off the Seychelles than in the other 2 areas. Calving rates showed the same trend, but differences between areas were not significant. Length distributions of females and immatures were similar off the Galapagos and Seychelles but rather larger animals were found off mainland Ecuador. There were very low densities of large, mature males in all areas. Our results, with the exception of the low feeding success and calving rate found off mainland Ecuador, are consistent with general models of density-dependent processes. The discrepancies may be due to migration of whales to mainland Ecuador from less exploited regions.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.