Regional differences in death rates among postneonatal infants in Kentucky, 1982-1985.

Our objective was to analyze differences in postneonatal mortality rates between the southeastern (Appalachian) region of Kentucky and the remainder of the state to identify factors associated with increased mortality in the Appalachian (AP) region. The relative risk of postneonatal deaths in the AP region when compared with the remainder of Kentucky (KY) was 1.38 (95% confidence interval = 1.15-1.65). Adjustment for birth weight, maternal age, and marital status of the parents had no appreciable effect on the risk ratio; however, adjustment for maternal education negated the increased risk of postneonatal death among the AP region births. When causes of postneonatal death were compared, three specific disease groupings were disproportionately represented among AP infants: Sudden Infant Death Syndrome (SIDS); congenital malformations; and infections. Most striking was the excess risk of infection-related death because it represents a preventable component in the postneonatal mortality excess of the AP region; and, because of the apparent association with maternal "under education." These findings are discussed within a public health intervention context.

Mammal teeth from the Cretaceous of Africa.

We report here the discovery of two mammal teeth from the early Cretaceous of Cameroon. These, and some jaw fragments, all from Cameroon, are the only fossil evidence of mammalian evolution from Africa between late Jurassic and Paleocene, a span of at least 85 million years. A triangular upper tooth lacks the principal internal cusp of marsupials and placentals and is therefore of a similar evolutionary grade to most Jurassic and early Cretaceous therian mammals, but more primitive than the metatherian-eutherian grade. Early Cretaceous, or older, therian mammals are now known from all southern continents except Antarctica. The new find from Cameroon is consistent with the hypothesis that marsupials, the dominant living mammals of South America and Australia, were not present on any Gondwana continents until after the early Cretaceous separation of Africa by the opening of the South Atlantic.