Origin of life on land, not in the sea?


This video says about itself:

2 May 2017

3.5 billion year old fossils hint life evolved in pond, not sea

It’s the age-old question: where do we come from? New fossil evidence suggests the first spark of life may have occurred in a hot spring on land rather than a hydrothermal vent in the deep sea.

Charles Darwin proposed in 1871 that life originated in a “warm little pond”. But the dominant theory nowadays is that primitive microorganisms first assembled in hot, chemical-rich water at hydrothermal vents at the bottom of the ocean.

One reason for favouring this marine model is that fossil evidence of early land-based microbial life has been lacking. Until recently, the oldest evidence of life on land was only 2.8 billion years old, whereas the oldest evidence from the sea was 3.7 billion years old.

Now, a team led by Tara Djokic at the University of New South Wales in Australia has discovered fossils of land-based microorganisms. They were found in 3.5-billion-year-old rocks in an extinct volcano in the Dresser Formation in the hot, dry, remote Pilbara region of Western Australia.

The fossils include stromatolites – layered rock structures created by microorganisms – and circular holes left in the rock by gas bubbles that look like they were once trapped by sticky microbial substances. Both types of structures are preserved in geyserite, a type of rock that is only found in and around freshwater hot springs in volcanic areas on land.

Land-based launch pad?

The findings suggest that microbes were present on land and in the ocean around the same time, says Djokic. The question is – which came first?

“There are now a number of converging lines of evidence that point to terrestrial hot springs over hydrothermal vents for the origin of life,” says Djokic.

Small bodies of water like hot springs may have been more conducive to the formation of life because they can evaporate and concentrate the building blocks of life, says Djokic. “In hot springs, you’ve also got a nutritious concoction of elements because hot fluids circulate through the underlying rocks and bring up different minerals,” she says.

Recent research suggests that the element mix in ancient hot springs would have been more likely to give rise to life than that of deep sea vents.

Primitive microorganisms formed in the springs could have then spread to the sea, where they could have adapted and continued to evolve, Djokic says.

The findings are compelling, says Gregory Webb at the University of Queensland in Australia. “There are lots of microbes that live in terrestrial hot springs today, so it’s not a stretch to believe that an ancient hot spring could have accommodated life,” he says.

Then again, making assertions about life on early Earth is tricky, says Webb. “Microbial life isn’t easy to see, even today, so rocks that preserve evidence of ancient bacteria are hard to find and hard to study.” He is not ruling out the deep sea model of the origin of life.

Ancient life on Mars

Djokic and her colleagues believe the research could have implications for the search for ancient life on Mars. Earth and Mars both formed around 4.5 billion years ago and had volcanoes and hot springs dotted across their surfaces.

“If life can be preserved in hot springs so far back in Earth’s history, then there is a good chance it could be preserved in Martian hot springs too,” says Djokic.

One of the three potential landing sites for NASA’s Mars 2020 rover mission is Columbia Hills, a rocky formation that is thought to have once been a hot spring environment.

From the University of California – Santa Cruz in the USA:

Did life begin on land rather than in the sea?

A paradigm-shifting hypothesis could reshape our idea about the origin of life

July 18, 2017

Summary: A new discovery pushes back the time for the emergence of microbial life on land by 580 million years and also bolsters a paradigm-shifting hypothesis that life began, not in the sea, but on land.

For three years, Tara Djokic, a Ph.D. student at the University of New South Wales Sydney, scoured the forbidding landscape of the Pilbara region of Western Australia looking for clues to how ancient microbes could have produced the abundant stromatolites that were discovered there in the 1970s.

Stromatolites are round, multilayered mineral structures that range from the size of golf balls to weather balloons and represent the oldest evidence that there were living organisms on Earth 3.5 billion years ago.

Scientists who believed life began in the ocean thought these mineral formations had formed in shallow, salty seawater, just like living stromatolites in the World Heritage-listed area of Shark Bay, which is a two-day drive from the Pilbara.

But what Djokic discovered amid the strangling heat and blood-red rocks of the region was evidence that the stromatolites had not formed in salt water but instead in conditions more like the hot springs of Yellowstone.

The discovery pushed back the time for the emergence of microbial life on land by 580 million years and also bolstered a paradigm-shifting hypothesis laid out by UC Santa Cruz astrobiologists David Deamer and Bruce Damer: that life began, not in the sea, but on land.

Djokic’s discovery — together with research carried out by the UC Santa Cruz team, Djokic, and Martin Van Kranendonk, director of the Australian Centre for Astrobiology — is described in an eight-page cover story in the August issue of Scientific American.

“What she (Djokic) showed was that the oldest fossil evidence for life was in fresh water,” said Deamer, a lanky 78-year-old who explored the region with Djokic, Damer, and Van Kranendonk in 2015. “It’s a logical continuation to life beginning in a freshwater environment.”

The model for life beginning on land rather than in the sea could not only reshape our idea about the origin of life and where else it might be, but even change the way we view ourselves.

The right conditions for life

For four decades, ever since the research vessel Alvin discovered deep-sea hydrothermal vents that were habitats for specialized bacteria and worms that looked like something out of a science-fiction novel, scientists have theorized that these mineral- and gas-pumping vents were just what was needed for life to begin.

But Deamer, who describes himself as a scientist who loves playing with new ideas, thought the theory had flaws. For instance, molecules essential for the origin of life would be dispersed too quickly into a vast ocean, he thought, and salty seawater would inhibit some of the processes he knew are necessary for life to begin.

Deamer had spent the early part of his career studying the biophysics of membranes composed of soap-like molecules that form the microscopic boundaries of all living cells. Later, given a piece of the Murchison meteorite that had landed in Australia in 1969, Deamer found that the space rock also contained soap-like molecules nearly 5 billion years old that could form stable membranes. Still later, he demonstrated that membranes helped small molecules join together to form longer information-carrying molecules called polymers.

Trekking to volcanoes from Russia to Iceland and hiking through the Pilbara desert, Deamer and his colleagues observed volcanic activity that suggested the idea that hot springs provided the right environment for the beginning of life. Deamer even built a machine that simulated the heat, acidity, and wet-and-dry cycles of hot springs and installed it in his lab on the UC Santa Cruz campus.

“I think, every once in awhile, you have to be brave enough and bold enough to try new ideas,” Deamer said. “Of course, some of my colleagues think even ‘foolish enough.’ But that’s the chance you take.”

Rethinking the timeline

In Deamer’s vision, ancient Earth consisted of a huge ocean spotted with volcanic land masses. Rain would fall on the land, creating pools of fresh water that would be heated by geothermal energy and then cooled by runoff. Some of the key building blocks of life, created during the formation of our solar system, would have fallen to Earth and gathered in these pools, becoming concentrated enough to form more complex organic compounds.

The edges of the pools would go through periods of wetting and drying as water levels rose and fell. During these periods of wet and dry, lipid membranes would first help stitch together the organic compounds called polymers and then form compartments that encapsulated different sets of these polymers. The membranes would act like incubators for the functions of life.

Deamer and his team believe the first life emerged from the natural production of vast numbers of such membrane-encased “protocells.”

While there is still debate about whether life began on land or in the sea, the discovery of ancient microbial fossils in a place like the Pilbara shows that these geothermal areas — full of energy and rich in the minerals necessary for life — harbored living microorganisms far earlier than believed.

The search for life on other planets

According to Deamer and his colleagues, this discovery and their hot-springs-origins model also have implications for the search for life on other planets. If life began on land, then Mars, which was found to have a 3.65-billion-year-old hot spring deposits similar to those found in the Pilbara region of Australia, might be a good place to look.

For Damer, the new “end-to-end hypothesis” of how life began on land offers something else: that the origin of life was not just a simple story of individual, competing cells. Rather that a plausible new vision of life’s start could be a communal unit of protocells that survived and evolved through collaboration and sharing of innovation rather than strict competition.

“That,” he said, “is a fundamental shift that might impact how we think of our world, ourselves, and our future: as dependent on collaboration as much as being driven by competition.”

Sitting in his fourth-floor office on campus, Deamer smiled as he recounted the letter Charles Darwin wrote to a friend in 1871, which speculated that life might have begun in “some warm little pond.”

That’s not far off the mark, Deamer said, “except we call ours ‘hot little puddles.'”

Conventional scientific wisdom has it that plants and other creatures have only lived on land for about 500 million years, but a new study is pointing to evidence for life on land that is four times as old — at 2.2 billion years ago and almost half way back to the inception of the planet: here.

The earliest example of an organism living on land — an early type of fungus — has been identified. The organism, from 440 million years ago, likely kick-started the process of rot and soil formation, which encouraged the later growth and diversification of life on land: here.

Hydroplaning dolphins in Australia


This video says about itself:

Hydroplaning Dolphins – Planet Earth – BBC Earth

2 May 2017

These remarkable Dolphins in Western Australia display incredible ingenuity when hunting for fish in the shallows. With little room for error, it would appear fortune does indeed favour the brave.

Australian dinosaur tracks, world’s most diverse


This 27 March 2017 video is called Dinosaur tracks found at ‘Australia’s Jurassic Park‘ in Walmadany.

From the University of Queensland in Australia:

‘Australia’s Jurassic Park’ the world’s most diverse

March 27, 2017

Summary: An unprecedented 21 different types of dinosaur tracks have been identified on a 25-kilometer stretch of the Dampier Peninsula coastline dubbed ‘Australia’s Jurassic Park.’ A team of paleontologists has unveiled the most diverse assemblage of dinosaur tracks in the world in 127 to 140 million-year-old rocks in the remote Kimberley region of Western Australia.

An unprecedented 21 different types of dinosaur tracks have been identified on a 25-kilometre stretch of the Dampier Peninsula coastline dubbed “Australia’s Jurassic Park.”

A team of palaeontologists from The University of Queensland’s School of Biological Sciences and James Cook University‘s School of Earth and Environmental Sciences braved sharks, crocodiles, massive tides and the threat of development to unveil the most diverse assemblage of dinosaur tracks in the world in 127 to 140 million-year-old rocks in the remote Kimberley region of Western Australia.

Lead author Dr Steve Salisbury said the diversity of the tracks around Walmadany (James Price Point) was globally unparalleled and made the area the “Cretaceous equivalent of the Serengeti.”

“It is extremely significant, forming the primary record of non-avian dinosaurs in the western half the continent and providing the only glimpse of Australia’s dinosaur fauna during the first half of the Early Cretaceous Period,” Dr Salisbury said.

“It’s such a magical place — Australia’s own Jurassic Park, in a spectacular wilderness setting.”

In 2008, the Western Australian Government selected Walmadany as the preferred site for a $40 billion liquid natural gas processing precinct.

The area’s Traditional Custodians, the Goolarabooloo people, contacted Dr Salisbury and his team, who dedicated more than 400 hours to investigating and documenting the dinosaur tracks.

“We needed the world to see what was at stake,” Goolarabooloo Law Boss Phillip Roe said.

The dinosaur tracks form part of a song cycle that extends along the coast and then inland for 450 km, tracing the journey of a Dreamtime creator being called Marala, the Emu man.

“Marala was the Lawgiver. He gave country the rules we need to follow. How to behave, to keep things in balance,” Mr Roe said said.

“It’s great to work with UQ researchers. We learnt a lot from them and they learnt a lot from us.”

Dr Salisbury said the surrounding political issues made the project “particularly intense,” and he was relieved when National Heritage listing was granted to the area in 2011 and the gas project collapsed in 2013.

“There are thousands of tracks around Walmadany. Of these, 150 can confidently be assigned to 21 specific track types, representing four main groups of dinosaurs, ” Dr Salisbury said.

“There were five different types of predatory dinosaur tracks, at least six types of tracks from long-necked herbivorous sauropods, four types of tracks from two-legged herbivorous ornithopods, and six types of tracks from armoured dinosaurs.

“Among the tracks is the only confirmed evidence for stegosaurs in Australia. There are also some of the largest dinosaur tracks ever recorded. Some of the sauropod tracks are around 1.7 m long.”

“Most of Australia’s dinosaur fossils come from the eastern side of the continent, and are between 115 and 90 million years old. The tracks in Broome are considerably older.”

The research has been published as the 2016 Memoir of the Society of Vertebrate Paleontology.

Ruby seadragons, first ever video


This video says about itself:

12 January 2017

Researchers at Scripps Oceanography and the Western Australian Museum capture on video the first-ever field sighting of the newly discovered third species of seadragon. As they observed two Ruby Seadragons on video for nearly 30 minutes, the scientists uncovered new details about their anatomy, habitat, and behavior.

See also here.

Western Australian coral reef, unique new research


This 2013 video from the Great Barrier Reef in Australia is called Scuba Diving with an Amazing Sea Cucumber.

From the Science Network Western Australia:

Rare chance at never-before-studied Kimberley reef

January 4, 2016 by Samille Mitchell

The weather gods conspired to provide a rare chance to survey a remote and rarely visited section of north Kimberley reef recently, with footage that will inform the future study of reefs through climate change.

Department of Parks and Wildlife (DPAW) researchers and Wunambal Gaambera traditional owners took advantage of the rare weather conditions to visit East Holothuria Reef, about 30km from the tip of Bougainville Peninsula, to conduct coral surveys.

They uncovered a flourishing and extremely biodiverse reef system, resplendent with corals and fishes, in a spectacular and never-before-studied part of the Kimberley’s underwater world.

“It is right in the top corner of the Bougainville Peninsula where wind-against-tides creates very rough sea conditions for much of the time,” says DPAW research scientist Andrew Halford.

“But we lucked-in with glass-off weather during neap tides—it was like a good perfect storm.”

The team traversed multiple 100-metre transects of the reef placing a camera on the bottom every 10 metres, which took photos every five seconds to record the diversity of the coral community.

Such footage will be used as a benchmark at monitoring sites across the north Kimberley, to enable conservation managers to study how reefs change and respond to different circumstances such as storms or a changing climate.

“We will be establishing long-term monitoring sites in the Kimberley that we can go back to and keep track of over time,” Dr Halford says.

“We’ll be able to see whether healthy reef communities can adapt to changing conditions over time.”

The big picture

The DPAW survey was part of a much larger examination of Kimberley benthic communities conducted by the Australian Institute of Marine Science, CSIRO, and the WA Museum, under the WA Marine Science Institute-managed Kimberley Marine Research Program.

These organisations are using large research vessels to study the diversity of the Kimberley marine benthic environment. The DPAW survey complimented their work by assessing shallower near-shore areas that are inaccessible to the larger boats.

Dr Halford says traditional owners are also playing an important role in monitoring these remote marine systems.

“As well as providing traditional knowledge of these areas, the idea is that eventually traditional owner groups will go out and do the surveying themselves,” Dr Halford says.

“They can take the footage and then the images can be sent to experts for analysis.”

‘Extinct’ Australian sea snakes rediscovered


This August 2015 video is called Top 10 Rarest Snakes In The World (Endangered Snakes).

From ScienceDaily:

Scientists discover rare sea snakes, previously thought extinct, off Western Australia

Date:

December 21, 2015

Source:

ARC Centre of Excellence in Coral Reef Studies

Summary:

Scientists have discovered two critically endangered species of sea snakes, previously thought to be extinct, off the coast of Western Australia. It’s the first time the snakes have been spotted alive and healthy since disappearing from their only known habitat on Ashmore Reef in the Timor Sea more than fifteen years ago.

Scientists from James Cook University have discovered two critically endangered species of sea snakes, previously thought to be extinct, off the coast of Western Australia.

It’s the first time the snakes have been spotted alive and healthy since disappearing from their only known habitat on Ashmore Reef in the Timor Sea more than fifteen years ago.

“This discovery is really exciting, we get another chance to protect these two endemic Western Australian sea snake species,” says study lead author Blanche D’Anastasi from the ARC Centre of Excellence for Coral Reef Studies at JCU.

“But in order to succeed in protecting them, we will need to monitor populations as well as undertake research into understanding their biology and the threats they face.”

The discovery of the critically endangered short nose sea snake was confirmed after a Western Australia Parks and Wildlife Officer, Grant Griffin, sent a photo of a pair of snakes taken on Ningaloo Reef to Ms D’Anastasi for identification.

“We were blown away, these potentially extinct snakes were there in plain sight, living on one of Australia’s natural icons, Ningaloo Reef,” says Ms D’Anastasi.

“What is even more exciting is that they were courting, suggesting that they are members of a breeding population.”

The researchers also made another unexpected discovery, uncovering a significant population of the rare leaf scaled sea snake in the lush seagrass beds of Shark Bay.

The discovery was made 1700 kilometres south of the snakes only known habitat on Ashmore Reef.

“We had thought that this species of sea snake was only found on tropical coral reefs. Finding them in seagrass beds at Shark Bay was a real surprise,” says Ms D’Anastasi.

Both leaf scaled and short nosed sea snakes are listed as Critically Endangered under Australia’s threatened species legislation, which means they have special protection.

Despite the good news of the find, sea snake numbers have been declining in several marine parks, and scientists are at a loss to explain why.

“Many of the snakes in this study were collected from prawn trawl by-catch surveys, indicating that these species are vulnerable to trawling,” says Dr Vimoksalehi Lukoschek from the Centre of Excellence for Coral Reef Studies.

“But the disappearance of sea snakes from Ashmore Reef, could not be attributed to trawling and remains unexplained.

“Clearly we need to identify the key threats to their survival in order to implement effective conservation strategies if we are going to protect these newly discovered coastal populations,” Dr Lukoschek says.

Two striking sea snakes have been spotted drifting off the coast of Western Australia, more than 15 years after the species was declared extinct. These bright yellow short nosed sea snakes (Aipysurus apraefrontalis) vanished from their natural habitat in the Timor Sea between 1998 and 2002, only to reappear in full view of a park ranger this month: here.