Cover Story: A Modus Vivendi? Sex, Marriage and the Church

The article presents divergent views on an analysis by historian Eamon Duffy of the Catholic Church\u27s response to shifting attitude towards sex and marriage in the West. Duffy noted that the church is increasingly confronted with the need to evolve a modus vivendi with social trends. Many Catholics are said to have disregarded the church\u27s teachings on sex and marriage. Other topics tackled include the increasing rate of divorce, premarital sex, same-sex unions and sexual education

A Modus Vivendi? Sex, Marriage & the Church

During the 1960s, nearly 80 percent of adult Americans were married. A recent analysis of U.S. census data reported that only 52 percent of adult Americans were married in 2009. That is the lowest percentage reported in the 100 years the Census Bureau has collected such information. The reasons for this dramatic cultural shift are well known: high rates of divorce; changing attitudes toward premarital sex; social acceptability of cohabitation; the weakening of the stigma surrounding out-of-wedlock births and single parenting; the postponement of marriage and children for academic or professional reasons. Among those with only a high-school education or less, the data suggest that the decision to marry has been made more difficult by deteriorating economic conditions

Genetic Evidence for a Mitochondriate Ancestry in the ‘Amitochondriate’ Flagellate Trimastix pyriformis

Most modern eukaryotes diverged from a common ancestor that contained the α-proteobacterial endosymbiont that gave rise to mitochondria. The ‘amitochondriate’ anaerobic protist parasites that have been studied to date, such as Giardia and Trichomonas harbor mitochondrion-related organelles, such as mitosomes or hydrogenosomes. Yet there is one remaining group of mitochondrion-lacking flagellates known as the Preaxostyla that could represent a primitive ‘pre-mitochondrial’ lineage of eukaryotes. To test this hypothesis, we conducted an expressed sequence tag (EST) survey on the preaxostylid flagellate Trimastix pyriformis, a poorly-studied free-living anaerobe. Among the ESTs we detected 19 proteins that, in other eukaryotes, typically function in mitochondria, hydrogenosomes or mitosomes, 12 of which are found exclusively within these organelles. Interestingly, one of the proteins, aconitase, functions in the tricarboxylic acid cycle typical of aerobic mitochondria, whereas others, such as pyruvate:ferredoxin oxidoreductase and [FeFe] hydrogenase, are characteristic of anaerobic hydrogenosomes. Since Trimastix retains genetic evidence of a mitochondriate ancestry, we can now say definitively that all known living eukaryote lineages descend from a common ancestor that had mitochondria