Slimy brown algae not only survived a wild ride into the stratosphere via a volcanic ash cloud, they landed on distant islands looking flawless, a new study finds.
"There’s a crazy contrast between these delicate, glass-shelled organisms and one of the most powerful eruptions in Earth’s history," said lead study author Alexa Van Eaton, a postdoctoral scholar at both the Cascades Volcano Observatory in Washington and Arizona State University.
The diatoms were launched by the Taupo super-eruption on New Zealand’s North Island 25,000 years ago. More than 600 million cubic meters (20 billion cubic feet) of diatoms from a lake flew into the air, Van Eaton reported Sept. 6 in the journal Geology. Lumped together, the microscopic cells speckled throughout Taupo’s ash layers would make a pile as big as Hawaii’s famed Diamond Head volcanic cone.
At a time when life as we know it was just getting its start on Earth, Martian clay may have harbored a key component for one of life’s molecular building blocks, researchers say.
Boron found in a Martian meteorite suggests the Red Planet may once have had the right chemistry to give rise to RNA, according to a new study.
“In early life RNA is thought to have been the informational precursor to DNA,” study researcher James Stephenson, an evolutionary biologist, said in a statement.
Billions of years ago, RNA may have been the first molecule to program information and pass it on to the next generation. Today, that task is DNA’s domain. RNA, meanwhile, is responsible for carrying genetic information from DNA to proteins. Researchers believe the RNA sugar component, ribose, relies on borates (the oxidized form of boron) to form spontaneously.
“Borates may have been important for the origin of life on Earth because they can stabilize ribose, a crucial component of RNA,” added Stephenson, who is a postdoctoral fellow at the University of Hawaii at Manoa NASA Astrobiology Institute (UHNAI).
Read more: [x]
Image: Electron microscope image showing the 700-million-year-old Martian clay veins containing boron. CREDIT: UHNAI
Confocal micrograph showing the expression of different fluorescent proteins in the stem of a thale cress seedling (Arabidopsis thaliana). Arabidopsis was the first plant to have its entire genome sequenced and is an important model for studying plant biology. The middle of the image shows a region of high cell proliferation, which drives the growth and branching of the seedling.
Stunning shots from the 2013 ATCC Photo Contest:
1. Mouse muscle cell (myoblast) 8 days after differentiation - The University of Iowa
2. Human cervix epithelial cells under multiphoton fluorescence - National Center for Microscopy and Imaging Research @ UCSD
SEM image (9,379x magnification) of a Zebrafish neuromast taken near the ear. Katie Kindt false-colored the image taken by Greg Baty.
Katie’s main interest in taking the SEM image was to examine the stereocilia and correlate the result with confocal studies that were performed while the zebra fish was alive. Katie and Gabe Finch at OHSU had a difficult time preparing the fish for SEM, due to the variability in a rapidly growing fish that is three days old. It took an interdisciplinary team effort to produce an image of this quality on a high vacuum XL30 Sirion.
Image courtesy of Greg Baty, Portland State University, Portland, Oregon
Chalk under a microscope.
“Chalk is composed of extremely small white globules. They look, up close, like snowballs made from brittle paper plates. Those plates, it turns out, are part of ancient skeletons that once belonged to roundish little critters that lived and floated in the sea, captured a little sunshine and carbon, then died and sank to the bottom… Scientists call these ancient plates ‘coccoliths.’”
Since Crick and Watson’s historic discovery of DNA, our investigation into coding DNA has gone a long way towards unravelling the key to life—but coding DNA only makes up just a few percent of the human genome. The rest is termed “Junk DNA” or “Non-coding DNA” because it doesn’t appear to have any function. However, new research suggests that this Junk DNA might actually play an important role in evolutionary history. Huge “ultraconserved” sections of it have remained the same for millions of years and are identical in many organisms—when you hear that humans and chimps share 98% of DNA, it’s mostly due to this. Increasing evidence suggests that Junk DNA influences coding DNA by acting as a kind of genetic “switch” in gene regulation, and it may also play a role in inheritance, but our knowledge is incomplete. If Junk DNA were really junk, then its sequence of “syllables” should be completely random, but it’s not random—leading scientists to believe it contains some kind of coded information. It’s been suggested that specific repetitive patterns are associated with susceptibility to cancer and other diseases, so understanding Junk DNA might be the key to understanding, diagnosing and curing disease.
Captured by Swiss photographer Fabian Oefner in his project Millefiori, the iron particles start to rearrange, forming black channels and separating the watercolours from the ferrofluid, creating these technicolour structures that look like psychedelic planets or trippy cells under a microscope.