Life Sciences and Chemistry

The first outbreak of the evolution of multicellular organisms falls on the Wend, the last period of the Proterozoic (Precambrian), about 620-550 million years ago. At that time, climate of our planet was rather cold, and glaciers that covered the single supercontinent nearly reached the equator. The cold is beneficial for the evolution of sea creatures.

In modern seas, significant concentrations of dissolved oxygen, phosphates, and the organic matter provide for a high biological productiv

The Johns Hopkins scientists who first discovered that knocking out a particular muscle gene results in “mighty mice” now report that it also softens the effects of a genetic mutation that causes muscular dystrophy.

The findings, scheduled for the December issue of the Annals of Neurology and currently online, build support for the idea that blocking the activity of that gene, known as myostatin, may one day help treat humans with degenerative muscle diseases.

Working with mice ca

Researchers at the University of Washington have discovered a cellular basis for what many have long suspected: Men, as well as women, have a reproductive clock that ticks down with age.

A recent study revealed that sperm in men older than 35 showed more DNA damage than that of men in the younger age group. In addition, the older men’s bodies appeared less efficient at eliminating the damaged cells, which could pass along problems to offspring.

“When you talk about having

A paper published today (26.11.02) in the December Issue of Journal of Applied Ecology by Cowgill et al describes the results of small-scale field trials that were used to assess the effect of PI-expressing potatoes on non-target soil organisms. The impact of a currently used PCN management option, the nematicide, aldicarb, on soil organisms was also studied.

The transgenic plants had an adverse effect on the fungal component of the soil microbial community, while the nematicide adversely

In the current crisis of global biodiversity loss, the discovery of new species is a welcome addition. But the recent finding that the mountain brushtail possum, an arboreal marsupial mammal of Australian wet forests, is actually made up of two species also poses new conservation challenges.

The new species is proposed in an article in the latest Australian Journal of Zoology (Volume 50, Issue 4), authored by Earthwatch-supported biologist Dr. David Lindenmayer (Australian National Universit

Phospholipid bilayers that mimic cell membranes in living organisms are of interest as substrates for biosensors and for the controlled release of pharmaceuticals. To better understand how these materials behave with embedded proteins, a necessary first step is to understand how the bilayers respond by themselves.

As will be reported in the Dec. 9 issue of Physical Review Letters (published online Nov. 21), scientists at the University of Illinois at Urbana-Champaign have studied the phase t