Through a series of Scanning Electron Microscopy images, Kellogg and colleagues show that inflorescences of most cool-season grasses grow in a "distichous" pattern, that is, in two opposite ranks of flower-bearing branches. Furthermore, this branching is oddly asymmetrical, with most branches forming on one side of the inflorescence. In contrast, inflorescences of most other grasses retain the ancestral arrangement of branches in a spiral, which is likewise retained in the inflorescences of the most basal genus of the cool-season grasses. The evolutionary innovation identified by Kellogg and colleagues helps to explain the great evolutionary success of this group, with contains approximately 3800 species spread across the Northern hemisphere, including important crops like wheat, barley, and oats.
Prof Elizabeth A. Kellogg
Department of Biology
University of Missouri, USA
Frontiers in Psychology
An inborn deficit causes children with dyscalculia to have an imprecise representation of numbers
Dyscalculia is a severe and persistent disability in learning arithmetic that is often highly selective, in that it can affect children with normal intellectual ability. Karin Landerl and her team at the University of Graz, Austria, investigated the development of numerical processing in elementary school children with dyscalculia and a control group with good arithmetic skills. Ch
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