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Maternal Contribution (maternal + contribution)
Selected AbstractsSocial dynamics and individual plasticity of infant care behavior in cooperatively breeding cotton-top tamarinsAMERICAN JOURNAL OF PRIMATOLOGY, Issue 4 2010Sofia Refetoff Zahed Abstract Individual variation in infant caretaking behavior is prevalent among marmoset and tamarin monkeys. Although most group members participate in infant care, the timing and amount provided differs greatly. In this study, we quantified general trends in infant carrying behavior by using a longitudinal database that included 11 years of instantaneous scan observations following 80 births of cotton-top tamarins. Using detailed focal observations on a subset of the same families (10 births) we identified influences that affected expression of infant care at the group and individual levels. Fathers were the primary carriers and paternal carry time gradually decreased with increasing infant age. Paternal carry time also decreased significantly with an increasing number of older sibling helpers. Most fathers began to carry on the first day postpartum. However, we report circumstances in which fathers delayed carrying until almost a month postpartum. Fathers retrieved infants the most, although adult brothers' rates of retrievals peaked and surpassed fathers' rates during week 4 postpartum. Fathers delayed rejection of infants until week 4, whereas mothers rejected infants immediately and throughout the eight weeks. Nonetheless, infants climbed onto their mothers more than onto any other family member. Mothers showed a high initial investment in carrying during the first two weeks, decreasing quickly thereafter. Maternal contributions to infant carrying remained low and relatively consistent regardless of group size. However, mothers dramatically increased their infant carrying behavior in families in which fathers were absent. Older siblings cared for infants more than did younger siblings, and brothers retrieved and carried infants more than did sisters. Individual expression of infant care changed to accommodate infant needs and changed according to varying social dynamics and circumstances across litters. Am. J. Primatol. 72:296,306, 2010. © 2009 Wiley-Liss, Inc. [source] Evolution of a novel function: nutritive milk in the viviparous cockroach, Diploptera punctataEVOLUTION AND DEVELOPMENT, Issue 2 2004Anna Williford Summary Cockroach species show different degrees of maternal contribution to the developing offspring. In this study, we identify a multigene family that encodes water-soluble proteins that are a major component of nutritive "Milk" in the cockroach, Diploptera punctata. This gene family is associated with the evolution of a new trait, viviparity, in which the offspring receive nutrition during the gestation period. Twenty-five distinct Milk complementary DNAs were cloned and partially characterized. These complementary DNAs encode 22 distinct Milk peptides, each of length 171 amino acids, including a 16-amino acid signal peptide sequence. Southern blot analysis confirms the presence of multiple copies of Milk genes in D. punctata. Northern analysis indicates tissue- and stage-specific Milk gene expression. Examination of the deduced amino acid sequences identifies the presence of structurally conserved regions diagnostic of the lipocalin protein family. The shared exon/intron structure of one of the Milk loci with lipocalin genes further supports a close evolutionary relationship between these sequences. [source] Genetic diversity of two haploid markers in the Udegey population from southeastern SiberiaAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 2 2010Han-Jun Jin Abstract The Udegeys are a small ethnic group who live along the tributaries of the Amur River Basin of southeastern Siberia in Russia. They are thought to speak a language belonging to a subdivision of the Tungusic-Manchu branch of the Altaic family. To understand the genetic features and genetic history of the Udegeys, we analyzed two haploid markers, mitochondrial DNA (mtDNA), and Y-chromosomal variation, in 51 individuals (including 21 males) from the Udegey population. In general, the Udegeys' mtDNA profiles revealed similarities to Siberians and other northeastern Asian populations, although a moderate European contribution was also detected. Interestingly, pairwise values of FST and the MDS plots based on the mtDNA variation showed that the Orok and Nivkh inhabiting the very same region of the Udegey were significantly different from the Udegey, implying that they may have been isolated and undergone substantial genetic drift. The Udegeys were characterized by a high frequency (66.7%) of Y chromosome haplogroup C, indicating a close genetic relationship with Mongolians and Siberians. On the paternal side, however, very little admixture was observed between the Udegeys and Europeans. Thus, the combined haploid genetic markers of both mtDNA and the Y chromosome imply that the Udegeys are overall closest to Siberians and northeast Asians of the Altaic linguistic family, with a minor maternal contribution from the European part of the continent. Am J Phys Anthropol, 2010. © 2009 Wiley-Liss, Inc. [source] Mitochondrial DNA HVRI variation in Balearic populationsAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 1 2005A. Picornell Abstract The Balearic archipelago (Majorca, Minorca, and Ibiza islands and the Chuetas, a small and inbred community of descendants of Sephardic Jews) and Valencia were studied by means of the sequencing of a 404-bp segment of hypervariable region I (HVRI) mtDNA in 231 individuals. In total, 127 different haplotypes defined by 92 variable positions were identified. The incidence of unique haplotypes was very low, especially in Ibiza and the Chuetas. A remarkable observation in the Chueta community was the high frequency (23%) of preHV-1, a Middle Eastern lineage that is closely related, though not identical, to many others found at high frequencies in different Jewish populations. The presence of this haplogroup convincingly supported the Jewish origin of the Chueta community. The studied populations showed a reduced African contribution, and no individuals were detected with North African haplogroup U6, indicating a lack of maternal contribution from the Moslem settlement to these populations. Only Ibiza showed a lower diversity, indicating a possible genetic drift effect, also supported by the historical information known about this island. The variability in the sequence of mtDNA hypervariable region I correlated well with the existing information from the populations, with the exception of that of the Y-chromosome, which could indicate a differential contribution of the maternal and paternal lineages to the genetic pool of the Balearic Islands. The phylogenetic trees showed the intermediate position of the Chueta population between the Middle Eastern and Majorcan samples, confirming the Jewish origin of this population and their Spanish admixture. Am J Phys Anthropol 128:119-130, 2005. © 2005 Wiley-Liss, Inc. [source] Diversity and phylogeny of mitochondrial DNA isolated from mithun Bos frontalis located in BhutanANIMAL GENETICS, Issue 5 2010T. Dorji Summary We sequenced the 16S rRNA gene in mitochondrial DNA to characterize mithun located in Bhutan and to increase our understanding of its origin. We compared mithun with yak, European cattle, Bhutanese zebu and Indian zebu. Sequencing revealed low nucleotide diversity within the mithun population and their phylogenetic proximity to gaur. A close relationship between Bhutanese mithun and gaur was confirmed by an additional comparison with wild gaur specimens from three locations in Bhutan. Direct domestication of mithun from gaur was supported, while maternal contribution from the cattle lineage during domestication was not supported. [source] Investigation of hatching and early post-embryonic life of freshwater crayfish by in vitro culture, behavioral analysis, and light and electron microscopyJOURNAL OF MORPHOLOGY, Issue 7 2008Günter Vogt Abstract The late embryonic and early post-embryonic life period of freshwater crayfish, which is the main time period of organogenesis, is poorly investigated because of the protective brooding behavior of crayfish mothers. A combination of in vitro culture, behavioral observations, and microscopic investigations of organs involved in hatching, attachment, exploration of the environment, and searching and processing of food yielded deeper insights in this important period of life. Experiments were performed with the robust parthenogenetic marbled crayfish. The following results were obtained: (1) Marbled crayfish can be raised in simple in vitro systems from 80% embryonic development to juvenile Stage 4 with up to 100% survival; (2) Hatching is prepared by chemical weakening of the egg shell and completed by levering actions of the hatchling's appendages; (3) The telson thread, a safety line that keeps the hatchling secured to the mother, is formed by secretions from the telson and the detaching inner layer of the egg case; (4) Molting Stage-1 juveniles are secured by an anal thread that results from delayed molting of the hindgut; (5) Active attachment of the hatchlings to the maternal pleopods with their 1st pereiopods is achieved by an innate fixed action pattern; (6) In vitro, juveniles are motile from Stage 2 despite incomplete development of their balance controlling statocysts. Movement pattern and social behavior vary greatly among individuals; and (7) Feeding starts in Stage 3, when the mouthparts and the gastric mill are fully developed. Onset of feeding is innate and does not require maternal contributions. In vitro culture of the isogenic marbled crayfish is recommended for broader use in research because it enables not only time and stage-specific sampling but also precisely timed experimental manipulations. J. Morphol., 2008. © 2008 Wiley-Liss, Inc. [source] The consequences of differential family survival rates and equalizing maternal contributions on the effective population size (Ne) of cultured silver-lipped pearl oysters, Pinctada maximaAQUACULTURE RESEARCH, Issue 8 2010Curtis E Lind Abstract The effective population size (Ne) is a critical gauge of how efficiently an aquaculture operation is capturing or maintaining genetic diversity and can govern the long-term success of genetic selection programmes. In communally reared pearl oysters (Pinctada maxima), high variance in family sizes is a significant contributor towards low Ne and its severity may be compounded by differential survival rates of individual families. To determine the effect of variable survival on Ne in cultured P. maxima, families from two commercial populations were analysed using DNA parentage analyses to monitor survival and changes in relative contributions. Significant shifts in relative contributions were observed between 72 days and 18 months of age in both commercial cohorts (P<0.001). Survival rates were found to be highly variable among families (ranging from 2.5% to 49.5%) when reared in a common environment. Additionally, we investigated whether equalizing maternal family sizes before communal rearing will reduce family size variance, and increase Ne, compared with stocking at naturally produced proportions. Family equalization (E) significantly improved Ne (P=0.013) compared with rearing at natural (N) proportions (E: Ne=7.18±0.34; N: Ne=5.60±0.15); however, this practice may unintentionally magnify negative influences of poor performing families if survival is correlated with other commercially important traits. It is concluded that highly variable family survival will affect Ne in communally reared P. maxima, and the practice of equalizing family sizes in order to maximize Ne may only become consistently beneficial once further progress is made towards understanding, and then reducing variation in family survival rates. [source] | ||||||||||