Ecology & Zoology

Plant and animal diseases can play a major and poorly appreciated role in allowing the invasion of exotic species, which in turn often threatens biodiversity, ecological function and the world economy, researchers say in a new report.

In particular, a plant pathogen appears to have opened the gate for the successful invasion of non-native grasses into much of California, one of the world's largest documented cases of invading species and one that dramatically changed the history and ecology of a vast grassland ecosystem.


Global air network showing hotspots for invasion of foreign species. Credit: University of Oxford.

Two Iowa State University botanists and their colleague at the University of North Carolina have discovered a new species of North American bamboo in the hills of Appalachia. It is the third known native species of the hardy grass. The other two were discovered more than 200 years ago.

Lynn Clark, Iowa State professor of ecology, evolution and organismal biology, and Ph.D. student Jimmy Triplett study bamboo diversity and evolution. They first heard about "hill cane" from Alan Weakley, a botanist at the University of North Carolina. Although the plant was known to the people in the area, its distinctiveness was not recognized.


Fig. 2. Arundinaria appalachiana. A.

Whip spiders, considered by many to be creepy-crawly, are giving new meaning to the term touchy-feely.

In two species of whip spiders, or amblypygids, mothers caress their young with long feelers, siblings stick together until they reach sexual maturity, and all mix in social groups. This is surprising behavior for these arachnids long-thought to be purely aggressive and anti-social, according to a Cornell researcher.


A mother amblypygid with several of her 7-month-old offspring. Their whips are touching one another.

Genetically modified crops were supposed to improve efficiency and make life easier for farmers in poor countries. The opposite may be true, according to a Washington University in St. Louis study. Technology may be racing too fast for farmers to keep up. It may even be linked to higher suicide rates.

The arrival of genetically modified crops has added another level of complexity to farming in the developing world, says a sociocultural anthropologist at Washington University in St. Louis.

Glenn D. Stone, Ph.D., professor of anthropology and of environmental studies, both in Arts & Sciences, at Washington University in St. Louis, has completed the first detailed anthropological fieldwork on these crops and the way they impact — and are impacted by — local culture.

 

 Soprano syndrome in the mousehouse?

One of the first things my mice did when introduced to their new Chinese-made home (details on that to come later) was to seek out their new boundaries. Then, almost as a herd, they sought out the little clear red mouse house in the center of the cage. Boundary, then home. I note this same basic instinct in the ethology of the three categories of mammals I observe the most: my nephews, my horse, and, now, my four black6 lab mice.

My mouse farm!

Today,after endless finessing, I finally got word that I will be getting my own mice. My own lab mice. To observe. At home.

Something about normal, run-of-the-mill plants limits their reach upward. There's been no way to create that magical beanstalk in the fairy tales but no one knows why. For more than a century, scientists have tried to find out which part of the plant both drives and curbs growth: is it a shoot's outer waxy layer? Its inner layer studded with chloroplasts? Or the vascular system that moves nutrients and water? The answer could have great implications for modern agriculture, which desires a modern magical bean or two.

Now, in the March 8 issue of the journal Nature, researchers in the Plant Biology Laboratory at the Salk Institute for Biological Studies provide the answer.

The fact that female wasp spiders have numerous sexual contacts is something which their male partners cannot prevent. What they can do, however, is ensure that no offspring ensue from these tête à têtes with their rivals: the male spiders simply place a chastity belt on their partner while copulating. The tip of their genital breaks off during intercourse, blocking the sexual orifice of the lady spider. Biologists from the universities of Bonn and Hamburg report on this amazing mechanism in the journal ‘Behavioral Ecology’ (vol. 18, pages 174-181, 2007).

When a male wasp spider discovers a potential partner, he turns her on by shaking her web. The female thereupon supports herself on her long legs on the web so that the male, who is much smaller, can then creep under her body.

A new genus of millipede was recently discovered by a Northern Arizona University doctoral student and a Bureau of Land Management researcher.

J. Judson Wynne, with the Department of Biological Sciences at NAU and cave research scientist with the U.S. Geological Survey's Southwest Biological Center, and Kyle Voyles, Arizona State Cave Coordinator for the Bureau of Land Management (BLM), collected specimens leading to the discovery of two new millipede species in caves on opposite sides of the Grand Canyon.

Wynne and Voyles, known for their cave research, also discovered a new genus of cricket last spring.

"We knew the millipedes likely represented two distinct species because the two populations were separated by the Grand Canyon," Wynne said.

A new study suggests that the iron-rich winter runoff from Pacific Northwest streams and rivers, combined with the wide continental shelf, form a potent mechanism for fertilizing the nearshore Pacific Ocean, leading to robust phytoplankton production and fisheries.

The study, by three Oregon State University oceanographers, was just published by the American Geophysical Union in its journal, Geophysical Research Letters.

West coast scientists have observed that ocean chlorophyll levels, phytoplankton production and fish populations generally increase in the Pacific Ocean the farther north you go (from southern California to northern Washington).