Speciation without Species: A Final Word

Gene transfer in bacteria: speciation without species?

Although Bacteria and Archaea reproduce by binary fission, exchange of genes among lineages has shaped the diversity of their populations and the diversification of their lineages. Gene exchange can occur by two distinct routes, each differentially impacting the recipient genome. First, homologous recombination mediates the exchange of DNA between closely related individuals (those whose sequen...

A Final Word about Stories

I STARTED THIS series talking about stories—how we learn best from hearing what others like us have experienced. I often rail at our community for not encouraging a more scienti c approach to decisionmaking. A question I commonly ask is, “How many of you looked at the randomized, double-blind, controlled experiments that clearly show that is better than <whatever you were...

Sympatric speciation without borders?

The biogeography of speciation remains a controversial issue and the process of allopatric speciation reigns. Sympatric speciation differs from allopatric speciation in terms of geographic setting and the role of selection in bringing about reproductive isolating mechanisms, making it a particularly fascinating and controversial subject for evolutionary biologists. Mayr (1947) explained the dif...

Speciation without Isolation

Microsoft Word - Final Knittle

Objectives: To determine whether the integrity of motivational interviewing (MI) delivery relates to short-term changes in physical activity (PA) and regulatory style within a sample of patients with rheumatoid arthritis, and to examine whether therapist proficiency in MI improves over time. Methods: During a randomized controlled trial to promote PA, 27 patients received a motivational intervi...