There are many galaxies of different shapes and sizes around us today. Roughly half are gas-poor elliptical-shaped galaxies with little new star formation activity, and half are gas-rich spiral and irregular galaxies with high star formation activity. Observations have shown that gas-poor galaxies are most often found near the centre of crowded galaxy clusters, whereas spirals spend most of their lifetime in solitude.
An extended view of the Hubble image also shows the gravitational lensing effect -- an optical illusion -- caused by the cluster's gravitational tidal forces of the cluster and "ram pressure stripping" by the hot gas.
As we have seen, penis size matters to female mice
and sword size matters to female swordfish
but brain size in humans barely gets noticed at all. It's what you do with it that counts.
The ability to hit a baseball or play a piano well is part practice and part innate talent. One side of the equation required for skilled performances has its roots in the architecture of the brain genetically determined before birth, say scientists at the Salk Institute for Biological Studies.
While humans can survive large temperature fluctuations, such species as corals are only comfortable within a 12-degree temperature range. And rising global temperatures appear to be threatening their survival, according to Drew Harvell, Cornell professor of ecology and evolutionary biology.
However, she noted in presenting a paper at the annual meeting of the American Association for the Advancement of Science in San Francisco, Feb. 18, Caribbean gorgonian sea fan corals show surprising warm-weather tenacity -- they not only are somewhat temperature resilient but can also boost their cellular and enzymatic defenses to fight lethal microorganisms as temperatures rise. These abilities may someday be harnessed to help protect other fragile coral reefs, Harvell said.
It's essential to all life, and numerous research papers are published about it every year. Yet there are still secrets to reveal about water, that seemingly simple compound we know as H2O.
Equipped with high-speed computers and the laws of physics, scientists from the University of Delaware and Radboud University in the Netherlands have developed a new method to "flush out" the hidden properties of water--and without the need for painstaking laboratory experiments.
The secrets of water revealed: UD's computer simulation of water molecules is based exclusively on quantum physics laws. Credit: Figure by Omololu Akin-Ojo and David Barczak, University of Delaware.
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.
The French Intergovernmental Panel on Climate Change (IPPC, or GIEC in French) has just announced the conclusions of its 4th report, which restates that global warming has increased the average temperature by 0.74°C over the last century. However, there is very little information about some parts of the planet, such as central Asia.