A trace fossil assemblage from fluvial Old Red deposits (Wood Bay Formation; Lower to Middle Devonian) of NW-Spitsbergen, Svalbard

From the fluvial Old Red Sandstone (ORS) of the Lower to Middle Devonian Wood Bay Formation (NW-Spitsbergen), a diverse trace fossil assemblage, including two new ichnotaxa, is described: Svalbardichnus trilobus igen. n., isp. n. is interpreted as the three-lobed resting trace of an early phyllocarid crustacean (Rhinocarididae). Cruziana polaris isp. n. yields morphological details that point towards a trilobite origin. This occurence of presumably marine trace makers in a fluvial red bed sequence raises the question of whether we are dealing with marine ingressions that are not sedimentologically expressed, with homeomorphy, or with an adaptation of marine groups to non-marine environments.     

The social organization of non-breeding Magpies Pica pica

The social behaviour of non-breeding individuals in a colour-marked population of Magpies was studied. In early autumn most non-breeders began to forage in a common area, the 'Non-breeding Flock Area'. A few individuals remained on their natal territories away from the flock area as solitary non-breeders. Most non-breeders were first-year birds, but some were second years or adults which no longer held a territory. Birds foraged in groups, their food intake rate differing with both group size and location. It appeared that the area in which birds foraged had a significant effect on food intake rate; foraging groups tended to form at sites rich in food. There was a dominance hierarchy amongst non-breeders; an individual's foraging behaviour, survivorship and chances of breeding were status dependent, with subordinates feeding less in groups and being less likely to survive and breed. Solitary individuals' chances of breeding were similar to those of high status birds, although their survivorship to breeding age may have been lower. Non-breeding Magpies are compared with non-breeders of other species and the factors which may influence their social behaviour are discussed. It is suggested that remaining as a solitary non-breeder is a viable alternative to becoming a low-status flock member for some birds.     

Effects of Antenatal Maternal Depression and Anxiety on Children’s Early Cognitive Development: A Prospective Cohort Study

Introduction

Studies have shown that depression or anxiety occur in 10–20% of pregnant women. These disorders are often undertreated and may affect mothers and children’s health. This study investigates the relation between antenatal maternal depression, anxiety and children’s early cognitive development among 1380 two-year-old children and 1227 three-year-old children.

Methods

In the French EDEN Mother-Child Cohort Study, language ability was assessed with the Communicative Development Inventory at 2 years of age and overall development with the Ages and Stages Questionnaire at 3 years of age. Multiple regressions and structural equation modeling were used to examine links between depression, anxiety during pregnancy and child cognitive development.

Results

We found strong significant associations between maternal antenatal anxiety and poorer children’s cognitive development at 2 and 3 years. Antenatal maternal depression was not associated with child development, except when antenatal maternal anxiety was also present. Both postnatal maternal depression and parental stimulation appeared to play mediating roles in the relation between antenatal maternal anxiety and children’s cognitive development. At 3 years, parental stimulation mediated 13.2% of the effect of antenatal maternal anxiety while postnatal maternal depression mediated 26.5%.

Discussion

The partial nature of these effects suggests that other mediators may play a role. Implications for theory and research on child development are discussed.