Archives de catégorie : sciences-general

Low oxygen levels could temporarily blind marine invertebrates

by Scripps Institution of Oceanography at the University of California San Diego, May 8, 2019 in ScienceDaily

These results, published recently in the Journal of Experimental Biology, are the first demonstration that vision in marine invertebrates is highly sensitive to the amount of available oxygen in the water.

Oxygen levels in the ocean are changing globally from natural and human-induced processes. Many marine invertebrates depend on vision to find food, shelter, and avoid predators, particularly in their early life stages when many are planktonic. This is especially true for crustaceans and cephalopods, which are common prey items for other animals and whose larvae are highly migratory in the water column.

Research on terrestrial animals has shown that low oxygen levels can affect vision. In fact, humans can lose visual function in low oxygen conditions. Pilots flying at high altitude, for instance, have been shown to experience vision impairment if aircraft fail to supplement cockpits with additional oxygen. Additionally, health problems such as high blood pressure and strokes, both associated with oxygen loss, can damage vision.

What would happen to Earth’s Climate and Weather if we had no Moon?

by A. Watts, February 15, 2019 in WUWT

A provocative hypothetical question: What if the Moon was not there? Video follows.

This giant rock lights up the night and can even change colors. So what would we do without it? Would we all need night vision goggles? How would it affect the ocean tides? Our seasons? Or our sleep cycles? Or would the consequences be far more drastic?

As the closest celestial body to our planet, the moon exerts a gravitational pull that governs much of what happens here on Earth Take the sea, for example. If you like surfing, you can thank the moon when the moon’s gravitational pull tugs on our spinning Earth, the oceans respond, giving us high tides in some parts of the world, and low tides elsewhere.

New islands, happy feet: Study reveals island formation a key driver of penguin speciation

by Molecular Biology and Evolution (Oxford University Press), February 5, 201 in ScienceDaily

Ever since Darwin first set foot on the Galapagos, evolutionary biologists have long known that the geographic isolation of archipelogos has helped spur the formation of new species.

Now, an international research team led by Theresa Cole at the University of Otago, New Zealand, has found the same holds true for penguins. They have found the first compelling evidence that modern penguin diversity is driven by islands, despite spending the majority of their lives at sea.

“We propose that this diversification pulse was tied to the emergence of islands, which created new opportunities for isolation and speciation,” said Cole.

Over the last 5 million years, during the Miocene period, (particularly within the last 2 million years), island emergence in the Southern Hemisphere has driven several branches on the penguin evolutionary tree, and also drove the more recent influence of human-caused extinctions of two recently extinct penguin species from New Zealand’s Chatham Islands.

German Scientists To More Closely Investigate Cloud Formation, A Vital Component In Climate

by P. Gosselin, January 27, 2019 in NoTricksZone

Leipzig, 20 December 2018

Researchers from Leipzig cooperate with scientists from Punta Arenas (Chile) to learn more about the relationship between air pollution, clouds and precipitation.

Leipzig/Punta Arenas. How do airborne particles, so-called aerosols, affect the formation and life cycle of clouds and precipitation? In order to come one step closer to solving this question, atmospheric scientists from the Leibniz Institute for Tropospheric Research (TROPOS) and the Leipzig Institute for Meteorology (LIM) at Leipzig University will observe the atmosphere at one of the cleanest places in the world for at least a year. The choice fell on Punta Arenas because the city is located on a comparable geographical latitude as Germany and will thus enable comparisons between the northern and southern hemispheres. The measurement campaign is part of the International Year of Polar Prediction (YOPP), which aims to improve weather and climate forecasts for the polar regions through intensive measurements.

Meteoroid Hits the Moon During Recent Lunar Eclipse

by Anthony Watts, January 22, 2019 in WUWT

This is a treat. On Jan. 21st, a meteoroid slammed into the Moon. We know this because many amateur astronomers witnessed the explosion and recorded video and photos. The fireball was visible against the shadowy backdrop of a total lunar eclipse. Video of the event follows.

We know this because many amateur astronomers witnessed or photographed the explosion. Petr Horálek was one of them; he captured the fireball from Boa Vista, one of the islands of Cape Verde …

Scientists identify two new species of fungi in retreating Arctic glacier

by Research Organization of Information and Systems, January 15, 2019 in ScienceDaily

Two new species of fungi have made an appearance in a rapidly melting glacier on Ellesmere Island in the Canadian Arctic, just west of Greenland. A collaborative team of researchers from Japan’s National Institute of Polar Research, The Graduate University for Advanced Studies in Tokyo, Japan, and Laval University in Québec, Canada made the discovery.

The scientists published their results on DATE in two separate papers, one for each new species, in the International Journal of Systematic and Evolutionary Microbiology.

“The knowledge of fungi inhabiting the Arctic is still fragmentary. We set out to survey the fungal diversity in the Canadian High Arctic,” said Masaharu Tsuji, a project researcher at the National Institute of Polar Research in Japan and first author on both papers. “We found two new fungal species in the same investigation on Ellesmere Island.”

Bacterial origin of the red pigmentation of Phanerozoic carbonate rocks: an integrated study of geology-biology-chemistry

by A. Préat et  al., December 2018 in GeologicaBelgica (with .pdf)


Explaining the color of rocks is still a complex problem. This question was raised long ago in the community of geologists, particularly for the pigmentation of the ‘red marbles’ of the Frasnian of Belgium at the beginning of the last century, with many unsatisfactory hypotheses. Our recent analysis of different red carbonate rocks in Europe and North Africa (Morocco) may provide an alternative explanation for the color of these rocks. For this it was necessary to bring together diverse and complementary skills involving geologists, microbiologists and chemists. We present here a synthesis of these works. It is suggested that the red pigmentation of our studied Phanerozoic carbonate rocks, encompassing a time range from Pragian to Oxfordian, may be related to the activity of iron bacteria living in microaerophilic environments. A major conclusion is that this red color is only related to particular microenvironments and has no paleogeographic or climatic significance. All red carbonates have not necessarily acquired their pigmentation through the process established in this review. Each geological series must be analyzed in the light of a possible contribution of iron bacteria and Fungi.

Mars: Oxygen-rich, life-supporting liquid water?

by California Institute of Technology, October 22, 2018 in ScienceDaily

A team led by scientists at Caltech and the Jet Propulsion Laboratory (JPL), which Caltech manages for NASA, has calculated that if liquid water exists on Mars, it could — under specific conditions — contain more oxygen than previously thought possible. According to the model, the levels could even theoretically exceed the threshold needed to support simple aerobic life.

That finding runs contrary to the current, accepted view of Mars and its potential for hosting habitable environments. The existence of liquid water on Mars is not a given. Even if it is there, researchers have long dismissed the idea that it might be oxygenated, given that Mars’s atmosphere is about 160 times thinner than that of Earth and is mostly carbon dioxide.

Ancient Mars had right conditions for underground life, new research suggests

by Brown University, September 24, 2018 in ScienceDaily/EPSL

A new study shows evidence that ancient Mars probably had an ample supply of chemical energy for microbes to thrive underground.

“We showed, based on basic physics and chemistry calculations, that the ancient Martian subsurface likely had enough dissolved hydrogen to power a global subsurface biosphere,” said Jesse Tarnas, a graduate student at Brown University and lead author of a study published in Earth and Planetary Science Letters. “Conditions in this habitable zone would have been similar to places on Earth where underground life exists.”

New research shows that ancient Mars likely had ample chemical energy to support the kinds of underground microbial colonies that exist on Earth.
Credit: NASA / JPL

BBC tells journalists that IPCC is God, can not be wrong –”No debate allowed”

by JoNova, September 8, 2018

Lets all bow to the IPCC — a modern God that shalt not be questioned. The Holy Sacred Climate Cow!

The IPCC is an unaudited and unaccountable foreign committee. Not only are no scientists paid to check its findings, now the publicly mandated BBC is making sure none of their journalists will check its findings either.

Carbonbrief has a copy of the BBC new internal guidance on how to report climate change.

In April, the UK regulator, Ofcom, found the BBC was guilty of not sufficiently challenging Lord Lawson, a skeptic. So in response the BBC now promises they will never sufficiently challenge the IPCC. That’s “false balance” for you.

Direct evidence of surface exposed water ice in the lunar polar regions

by Shaui Li et al., August 20, 2018 PNAS

We found direct and definitive evidence for surface-exposed water ice in the lunar polar regions. The abundance and distribution of ice on the Moon are distinct from those on other airless bodies in the inner solar system such as Mercury and Ceres, which may be associated with the unique formation and evolution process of our Moon. These ice deposits might be utilized as an in situ resource in future exploration of the Moon.

Integrated genomic and fossil evidence illuminates life’s early evolution and eukaryote origin

by Holly C. Betts et al., August 20, 2018 in NatureEcology&Evolution

We derive a timescale of life, combining a reappraisal of the fossil material with new molecular clock analyses. We find the last universal common ancestor of cellular life to have predated the end of late heavy bombardment (>3.9 billion years ago (Ga)). The crown clades of the two primary divisions of life, Eubacteria and Archaebacteria, emerged much later (<3.4 Ga), relegating the oldest fossil evidence for life to their stem lineages. The Great Oxidation Event significantly predates the origin of modern Cyanobacteria, indicating that oxygenic photosynthesis evolved within the cyanobacterial stem lineage. Modern eukaryotes do not constitute a primary lineage of life and emerged late in Earth’s history (<1.84 Ga), falsifying the hypothesis that the Great Oxidation Event facilitated their radiation…

The Medusae Fossae Formation as the single largest source of dust on Mars

by L. Ojha et al., July 20, 2018 in NatureCommunications (open access)

Transport of fine-grained dust is one of the most widespread sedimentary processes occurring on Mars today. In the present climate, eolian abrasion and deflation of rocks are likely the most pervasive and active dust-forming mechanism. Martian dust is globally enriched in S and Cl and has a distinct mean S:Cl ratio. Here we identify a potential source region for Martian dust based on analysis of elemental abundance data …

Invisible Scientific Debates Accomplish Nothing

by Donna Laframboise, April 23, 2018 in ClimateChangeDispatch

SPOTLIGHT: After the Intergovernmental Panel on Climate Change (IPCC) report was released in 2007, its dramatic findings of species extinction were repeatedly emphasized by chairman Rajendra Pachauri.

BIG PICTURE: When it examined the question of species extinction, the 2007 IPCC report relied heavily on a single piece of research – a Nature cover storypublished early in 2004. Written by Chris Thomas and 18 others, this was the source of Pachauri’s claim that climate change threatened 20 to 30% of the world’s species.