Giant mouse lemur

A new population of rare giant mouse lemurs was discovered in southwestern Madagascar’s Ranobe forest, in an area threatened by mining concessions, WWF said today.

“Last year during a night survey monitoring biodiversity along the gallery forest of Ranobe near Toliara…Charlie Gardner and Louise Jasper came across a giant mouse lemur (Mirza) foraging within fruiting ficus” trees, WWF said in information released with this photograph.

Two species of giant mouse lemurs are known: Mirza coquereli and Mirza zaza.

Mirza coquereli (Coquerel’s mouse lemur) is found in the southwestern spiny forest eco-region, but has never been seen in the Toliara area before, WWF said.

Coquerel’s mouse lemurs are Near Threatened according to the International Union for Conservation of Nature (IUCN), which means that they might qualify for vulnerable, endangered or critically endangered in the near future.

“Their population trend is decreasing. The discovery of a new population is exciting as it raises hopes for the species’ survival,” said WWF, which is a Switzerland-based conservation organization.

New species?

The species seen in the Ranobe gallery forest exhibits “significant differences in the coloration of its coat from the other two species,” according to the researcher Charlie Gardner, who is from the University of Kent. He and Jasper were working on a project for WWF when they spotted the giant mouse lemur.

“The specimen that we observed appears to have a lighter dorsal coloration than is noted for M. coquereli, and has conspicuous reddish or rusty patches on the dorsal surface of the distal ends of both fore and hind-limbs. The ventral pelage is also conspicuously light in color, and the animal possesses a strikingly red tail, also becoming darker at the end.”

“This is to suggest that it may not only be a new population, but a new species or subspecies,” Gardner said. However, the animal has to be trapped, examined and tested before it can be officially described as a new species, he added.

“These findings not only highlight the biological importance of the area, but also emphasise how little we know about these rapidly disappearing forests.”

“These findings not only highlight the biological importance of the area, but also emphasise how little we know about these rapidly disappearing forests. Without the creation of new protected areas, we would risk losing species to extinction before they have even been discovered or described,” WWF said.

“These animals, in turn, can attract tourism and conservation revenue to the site which can help local communities to find less destructive ways to meet their development needs.”

This new lemur population is not the first exciting discovery from Ranobe in recent years, according to WWF.

In 2005 scientists described the rediscovery of Mungotictis decemlineata lineata, a subspecies of the narrow-striped mongoose that had not been observed since 1915, and which was only ever known from a single specimen. This subspecies may be entirely restricted to a protected area in Ranobe.

The representative of the new Mirza population was discovered just outside the limits of the protected area, WWF said. “It highlights the critical need to extend the limits of this protected area.”

The protected area, known as PK32-Ranobe[ML1] , is co-managed by WWF and the inter-communal association MITOIMAFI. It received temporary protection status in December 2008. “However, due to the presence of mining concessions, the limits of the protected area did not extend to include the gallery forests of Ranobe,” WWF said.

“It is a hotspot of biodiversity clamped on almost all sides by mining concessions.”

“It is a hotspot of biodiversity clamped on almost all sides by mining concessions. WWF is currently applying for the extension of the PA to include more key habitats within the decree of definitive protection,” Malika Virah-Sawmy, WWF’s Terrestrial Programme Coordinator in Madagascar said.

“Every year, large areas of Ranobe forests are felled by charcoal sellers, and in the past, much of the region was granted for mining concessions for the various minerals deposited in its rich sand soils. Meagre crops of maize are also planted on the calcareous soils, after felling and burning the forests,” WWF said.

The new protected area is part of a new philosophy promoted by WWF for the Durban Vision which aims to triple the surface area of Madagascar protected areas, the conservation group said. “WWF aims to empower communities to co-manage PA and to find ways for communities to benefit economically protecting their environment.”

Gardner’s research, based at the University of Kent, is focused on reconciling conservation and sustainable rural development within new protected areas. This research will inform the management of PK32-Ranobe, allowing the identification of win-win scenarios that benefit all stakeholders, WWF said.

“We hope the area will not only represent the single most important conservation area within the Spiny forest, but also a place where communities are benefiting from conservation through ecotourism and other sustainable livelihoods,” said Virah-Sawmy.

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Polar Algae Forests

The rarely seen creatures in Antarctica’s lush algae “forests” are the subjects of a University of Alabama at Birmingham search for potential new cancer medicines.

The cold waters near Antarctica are filled with lush forests of 4 main species of large algae plants, or seaweeds.

Researchers are comparing their pervasiveness to giant kelp forests of the more temperate Pacific coast of California.

SOUNDBITE: Chuck Amsler, Phycologist, Univ. of Alabama at Birmingham: “You enter these dense forests. They rise up 3 or 4 feet off the bottom just carpeting the bottom.”

Researchers have found the plants and invertebrates in this region produce defensive chemicals, and some are under study for the treatment of at least one type of cancer.

Researchers from the University of Alabama at Birmingham are in the midst of a 3-month diving expedition to the frozen continent.

The video, shot by lead researcher Chuck Amsler, shows lush growths below the ocean surface along the western side of Antarctica’s peninsula.

SOUNDBITE: Chuck Amsler, Phycologist, Univ. of Alabama at Birmingham: “You don’t think about there being forests in Antarctica. But there truly are these forests of giant seaweeds underneath the surface of the water.”

The large brown algae forest includes one species that can grow up to 50 feet in length and up to 4 feet wide. These lie on the bottom, at a depth of 100 feet and more, and cover the floor nearly 100 percent in some areas.

Another brown macroalgae, or seaweed, has small spherical gas-filled bladders to make it buoyant, and the 6 foot tall plants stay upright.

Smaller algae grows at shallower depths, but still, often covers the sea floor.

These lush Antarctic forests are different from their counterparts in warmer climates.

SOUNDBITE: Chuck Amsler, Phycologist, Univ. of Alabama at Birmingham: “And what’s unusual compared to other large forests of algae in other places in the world, is that these forests of algae are chemically defended. They are using compounds to make them taste bad.”

By tasting bad, large algae doesn’t get eaten by other organisms. They feast on smaller algae, and that in turn keeps the small algae from encroaching on the big algae.

Then, besides the forests, there is other thriving life in these cold waters.

SOUNDBITE: Chuck Amsler, Phycologist, Univ. of Alabama at Birmingham: “There are lots of very steep shores, where especially when we get down deep, we get to be on pretty much vertical walls. And when you’re on vertical walls, and there are overhangs and things, the big seaweeds don’t do as well. And that’s where we can start to find really lush and really diverse communities of sponges and colonial sea squirts or tunicates, soft corals, you don’t think about corals, and it’s not hard re-forming corals but gorgonian and soft corals. And they will cover nearly a 100 percent or certainly well over 60-70 percent of that surface.”

From some of the tunicates, the researchers discovered a compound that in the laboratory, in early studies, has been shown to combat some forms of melanoma in mice.

SOUNDBITE: Jim McClintock, Marine Chemical Ecologist, UAB: “We certainly have the potential of discovering a compound that could help fight cancer, or AIDS or a flu virus, these types of things.”

Because the water is so cold, the researchers’ dives are limited to 30-40 minutes at a time. They wear thick layers of underwear under dry suits, but their hands do get cold.

SOUNDBITE: Chuck Amsler, Phycologist, Univ. of Alabama at Birmingham: “Unfortunately, if we wore as much on our hands as we wore everywhere else, we’d be wearing boxing gloves and we wouldn’t get a lot of work done. So you’re hands get cold. We have some tricks, and chemical heater packs on the hands are nice.”

Their primary goal on these dive studies is to find out more about the ecosystems in these underwater forests, and learn about the relationships between the creatures and plants that live there.

The University of Alabama at Birmingham in Antarctica expedition is funded by the National Science Foundation.

http://video.nationalgeographic.com/video/player/flash/syndicatedVideoPlayer.swf?vid=antarctica-algae-forest-lb-vin

http://video.nationalgeographic.com/video/player/flash/syndicatedVideoPlayer.swf?vid=antarctica-algae-forest-lb-vinsource

Scientists find creatures beneath 600 feet of ice

In a surprising discovery about where higher life can thrive, scientists for the first time found a shrimp-like creature and a jellyfish frolicking beneath a massive Antarctic ice sheet.

Six hundred feet below the ice where no light shines, scientists had figured nothing much more than a few microbes could exist.

That’s why a NASA team was surprised when they lowered a video camera to get the first long look at the underbelly of an ice sheet in Antarctica. A curious shrimp-like creature came swimming by and then parked itself on the camera’s cable. Scientists also pulled up a tentacle they believe came from a foot-long jellyfish.

“We were operating on the presumption that nothing’s there,” said NASA ice scientist Robert Bindschadler, who will be presenting the initial findings and a video at an American Geophysical Union meeting Wednesday. “It was a shrimp you’d enjoy having on your plate.”

“We were just gaga over it,” he said of the 3-inch-long, orange critter starring in their two-minute video. Technically, it’s not a shrimp. It’s a Lyssianasid amphipod, which is distantly related to shrimp.

The video is likely to inspire experts to rethink what they know about life in harsh environments. And it has scientists musing that if shrimp-like creatures can frolic below 600 feet of Antarctic ice in subfreezing dark water, what about other hostile places? What about Europa, a frozen moon of Jupiter?

“They are looking at the equivalent of a drop of water in a swimming pool that you would expect nothing to be living in and they found not one animal but two,” said biologist Stacy Kim of the Moss Landing Marine Laboratories in California, who joined the NASA team later. “We have no idea what’s going on down there.”

Microbiologist Cynan Ellis-Evans of the British Antarctic Survey called the finding intriguing.

“This is a first for the sub-glacial environment with that level of sophistication,” Ellis-Evans said. He said there have been findings somewhat similar, showing complex life in retreating ice shelves, but nothing quite directly under the ice like this.

Ellis-Evans said it’s possible the creatures swam in from far away and don’t live there permanently.

But Kim, who is a co-author of the study, doubts it. The site in West Antarctica is at least 12 miles from open seas. Bindschadler drilled an 8-inch-wide hole and was looking at a tiny amount of water. That means it’s unlikely that that two critters swam from great distances and were captured randomly in that small of an area, she said.

Yet scientists were puzzled at what the food source would be for these critters. While some microbes can make their own food out of chemicals in the ocean, complex life like the amphipod can’t, Kim said.

So how do they survive? That’s the key question, Kim said.

“It’s pretty amazing when you find a huge puzzle like that on a planet where we thought we know everything,” Kim said.

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All-black penguin discovered

King Penguins are notorious for their prim, tuxedoed appearance — but a recently discovered all-black penguin seems unafraid to defy convention. In what has been described as a “one in a zillion kind of mutation,” biologists say that the animal has lost control of its pigmentation, an occurrence that is extremely rare. Other than the penguin’s monochromatic outfit, the animal appears to be perfectly healthy — and then some. “Look at the size of those legs,” said one scientist, “It’s an absolute monster.” The under-dressed penguin was photographed by Andrew Evans of National Geographic on the island of South Georgia near Antarctica. As the picture circulated, some biologists were taken aback — including Dr. Allan Baker of the University of Toronto.

His first response was disbelief:

Wow. That looks so bizarre I can’t even believe it. Wow.

While multicolored birds will often show some variation, Dr. Baker explains that what makes this all-black King Penguin so rare is that the bird’s melanin deposits have occurred where they are typically not present — enough so that no light feathers even checker the bird’s normally white chest.

Andrew Evans:

Melanism is merely the dark pigmentation of skin, fur — or in this case, feathers. The unique trait derives from increased melanin in the body. Genes may play a role, but so might other factors. While melanism is common in many different animal species (e.g., Washington D.C. is famous for its melanistic squirrels), the trait is extremely rare in penguins. All-black penguins are so rare there is practically no research on the subject — biologists guess that perhaps one in every quarter million of penguins shows evidence of at least partial melanism, whereas the penguin we saw appears to be almost entirely (if not entirely) melanistic.

Whether or not the all-black look catches on in the penguin fashion world, it’s nice to see someone dressing-down for once.

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Chinese grandmother grows mystery horn on forehead

An elderly Chinese woman has stunned her family and fellow villagers by growing from her forehead a horn than resembles a goat’s.

Grandmother Zhang Ruifang, 101, of Linlou village, Henan province, began developing the mysterious protrusion last year.

Since then it has grown 2.4in in length and another now appears to emerging on the other side of the mother of seven’s forehead.

Zhang Ruifang began growing a horn last year. It is now 2.4in long

The condition has left her family baffled and worried.

Her youngest of six sons, Zhang Guozheng, 60, said when a patch of rough skin formed on her forehead last year ‘we didn’t pay too much attention to it’.

‘But as time went on a horn grew out of her head and it is now 6cm long,’ added Mr Zhang, whose eldest brother and sibling is 82 years old.

‘Now something is also growing on the right side of her forehead. It’s quite possible that it’s another horn.’

Although, it is unknown what the protrusion is on Mrs Zhang’s head, it resembles a cutaneous horn.

This is a funnel-shaped growth and although most are only a few millimetres in length, some can extend a number of inches from the skin.

Cutaneous horns are made up of compacted keratin, which is the same protein we have in our hair and nails, and forms horns, wool and feathers in animals.

They usually develop in fair-skinned elderly adults who have a history of significant sun exposure but it is extremely unusual to see it form protrusions of this size.

The growths are most common in elderly people, aged between 60 and the mid-70s. They can sometimes be cancerous but more than half of cases are benign.

Common underlying causes of cutaneous horns are common warts, skin cancer and actinic keratoses, patches of scaly skin that develop on skin exposed to the sun, such as your face, scalp or forearms.

Cutaneous horns can be removed surgically but this does not treat the underlying cause.

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Great white sharks VS Giant squids

New studies suggest that great white sharks may migrate so they can dine on giant squids.

VS.

In what could be the ultimate marine smack-down, great white sharks off the California coast may be migrating 1,600 miles west to do battle with creatures that rival their star power: giant squids.

A series of studies tracking this mysterious migration has scientists rethinking not just what the big shark does with its time but also what sort of creature it is.

Few sea denizens match great white sharks and giant squids in primitive mystique. Both are the subject of popular mania; both are inscrutable. That these two mythic sea monsters might convene for epic battles in the stark expanses of the Pacific is enough to make a documentarian salivate.

For more reserved scientists, the possible link between sharks and squid, suggested by marine ecologist Michael Domeier of the Marine Conservation Science Institute in Fallbrook, is just one part of emerging research that has altered their understanding of the great whites.

The shift began eight years ago with the surprising discovery that great white sharks migrate, somewhat as humpback whales do. That and subsequent studies have demolished the iconic image of great whites lurking in relative shallows, ready to snatch an errant swimmer, as popularized in the movie “Jaws.”

Domeier said he believes the animals “are not a coastal shark that comes out to the middle of the ocean. They are an ocean shark that comes to the coast. It is a complete flip-flop.”

Picture them not as a dorsal fin off the beach but rather as an unseen leviathan swimming through black depths where the oxygen thins and fish glow in the dark, and maybe pouncing on a 30-foot squid.

The squid part is controversial. But Domeier’s work and that of other scientists increasingly suggests that great white sharks are not randomly roving eating machines.

Instead, they obey set migration patterns, have distinct populations and return to the same locales. They are not desperadoes but dutiful migrants: Nomads but not outlaws, they yearn for home.


But this new understanding raised a question: Why would an animal so large, that grows teeth as humans grow hair, bother to go so far when it can dine on just about anything in fin’s reach? The migration is especially puzzling because it means sharks miss out on coastal food supplies, said the University of Hawaii’s Kevin Weng, who also tracked sharks’ migration.

Determined to find the reason, Domeier and his team spent three years catching 22 great whites off Mexico’s Guadalupe Island, southwest of San Diego, and bolting high-tech tags to their fins. The area, like California’s Farallon Islands, is a hot spot for shark visits.

The team used hooks that could cradle a volleyball. They wrestled the sharks onto platforms, lifted them aboard their vessel and put towels over their eyes. The 4,000-pound predator is only a minor threat out of water, Domeier said. But after being thwacked off his feet, he learned to tie up their tails.

Funded by Newport Beach’s George T. Pfleger Foundation and others, Domeier arranged a voyage with a National Geographic Channel television crew to follow the sharks in a 126-foot boat. The crew used the tags to track the sharks to an area of the deep Pacific about 1,500 miles east of Kauai that scientists consider an ecological desert because it is so biologically unproductive.

There, the sharks abruptly ended their migration, and satellite tags showed them milling around and diving.

Despite hours of surveys and trolling during last spring’s monthlong voyage, members found barely any fish or other prey that the sharks might be eating.

But there was an exception: squids. Purple and neon flying squids were easy to find. There also were leaping sperm whales, a marine mammal known to feed in spawning areas for large squids. To Domeier, it was clear: The sharks had found a squid-based ecosystem with big enough prey to attract sperm whales.

Finally, the crew found a whitish carcass of a giant squid that had been chewed on, perhaps by various predators. Because of the lack of alternative food sources, and the pinging tags that traced deep and frequent dives, Domeier said, he formed a speculative conclusion: The sharks go to the area for the same reason as sperm whales: to feed on large squids, including the giant ones in the area, and on various predators the squids attract.

The weather turned bad, and the investigation ended early. The trip back was boring enough for the crew to form a band, then break up.

Domeier said he believes the sharks return to the coast to breed. His tags showed that some females stayed out at sea full-time.

The idea has set off robust debate. Some scientists argue it remains possible that the sharks mate offshore, and all agree that more research is needed to determine exactly what, and when, they eat. And it’s highly unlikely anyone will ever see a shark making an easy kill of giant squid.

But Oscar Sosa-Nishizaki, a fisheries biologist in Ensenada, said the tagging effort helps researchers count sharks and plan conservation efforts.

Shark scientists face a dilemma: There is intense popular interest in their work, but some fret that it may hinder conservation. Media interest in sharks tends to be “sparse on detail, high on testosterone,” said marine biologist Weng. “It’s as if aliens were to visit planet Earth, and the only thing they saw of human beings was ultimate fighting on TV.”

Though wary of pop biology, Domeier made the most of it. He used his time on camera to lobby against eating bluefin tuna and Chilean sea bass.

If mythic predator-mania gave him the chance, so be it, he said. “We are at a state of real disaster of our oceans,” he said. “Perhaps the scientific routine . . . doesn’t work.”

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Mysterious headless marine animal washes ashore

Neither local residents Warrick Lovell, Rich Park, Basil Park, or anyone else it seems, knows what the big creature found dead on a beach here this week might be.

The Department of Fisheries and Oceans in Corner Brook intends to check out the Lower Cove site today hoping to find some answers for the question of many curious onlookers who went there to see for themselves what Lovell found during a Wednesday afternoon walk on the beach.

“It would be nice to see if anyone knows what it is,” says Lovell. “First I thought it was a seal washed up (on the high tide earlier in the day), but when I went down to check on my boat that evening, I walked over to see and then I knew it wasn’t a seal.

“But, I don’t know what it is.”

Of unknown origin and species, so far, the odd-looking seaside carcass sits high and dry on the low tide, its approximately 15-foot length includes a pointed, 10-foot tail twisted in the sand, conjuring up Loch Ness monsters for some.

The animal, bearing a single flipper-like appendage on its right side, appears to have been decapitated and shows other signs of damage.

“I didn’t know what to think of it,” says Rich Park, also among the first to see it close up.

The long tapered tail on the squared torso of the carcass caused him to initially think the large hunk of flesh might be a tentacle off a giant squid Park said, but on closer inspection it became clearer what the protrusion was not that. It got hair on it in spots. I couldn’t (determine) what it was.”

“I’ve lived here all my life and never seen anything like it,” says Basil Park, who went Thursday went to take a look with friends and brothers Gilbert and Ernie Park, and neither one of them could say they knew what it was.

“There’s fishermen around here who fished all their lives and they couldn’t tell you.”

John Lubar with DFO says the Corner Brook office receives a number of calls from residents around the region each year reporting seals in brooks or to have rotting carcasses of whales or other dead things removed from a shoreline, but claims reports of unknown creatures from the deeps washing up are rare.

Common knowledge of the McIvers find spread by word of mouth over the past few days and at least one visitor to the site photographed the carcass and has posted it on Facebook.

DFO expects to have personnel in McIvers to do an inspection of Lower Cove by noon today.

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Killer whale Shamu kills trainer at SeaWorld

ORLANDO, FL – A trainer at SeaWorld in Orlando, Florida, was killed by a killer whale Wednesday afternoon, according to authorities.

The orca whale grabbed the trainer by the waist while she was talking about the whale, according to a witness. Another report had the trainer slipping or falling into the whale’s tank.

Emergency personnel pronounced the trainer dead at the scene. Her name has not been released.

The whale is Tilikum, a 12,300-pound bull orca.

The attack occurred in the park’s Shamu Stadium. The killer whale show has been indefinitely suspended and part of the park has been closed because of the attack.

Previous incident

According to The Associated Press, Wednesday’s incident was not the first time the nearly 30-year-old Tilikum has been linked to an attack.

In July 1999, the body of a naked man was found scratched, bruised and draped over 5-ton Tilikum. Daniel Dukes, 27, reportedly made his way past security at SeaWorld, remaining in the park after it had closed. Wearing only his underwear, Dukes either jumped, fell or was pulled into the frigid water of Tilikum’s huge tank.

An autopsy determined Dukes died of hypothermia in the 50-degree water. But the report also found it appeared Tilikum bit the man and tore off his swimming trunks, likely believing he was a toy to play with.

An investigation into what may have prompted Wednesday’s incident was beginning.

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Has the Cetacean Uprising of 2010 begun? With Shamu killing a trainer at SeaWorld this afternoon, we have to ask: was this merely an act of workplace violence, or was the whale a terrorist who was angry about being forced to pay his taxes even though he isn’t even a human? Or was Shamu talking to a Yemeni cleric on the Internet who convinced him that this was a good way to go to heaven as an Islamist martyr?

All joking aside, an Orca or killer whale killed an unnamed trainer at SeaWorld in Florida today, and all live killer whale shows have been suspended, according to the Orlando Sentinel. Of course, Shamu is not just one whale – it can be any number of male or female whales kept by the park.

And, it’s not the first time the trainers have had problems with ‘Shamu.’ Here is a video from the show Maximum Exposure that shows a whale wigging out during a training session:

The Orlando Sentinel described today’s attack in this manner:

“Park guest Victoria Biniak told Local 6 that the trainer was a veteran of SeaWorld and had just finished explaining to the audience what they would see during the performance.

At that point, Biniak said, the whale came up from the water and grabbed the woman.

The whale “took off really fast in the tank, and then he came back, shot up in the air, grabbed the trainer by the waist and started thrashing around, and one of her shoes flew off.”

I guess it’s necessary to remind everyone that killer whales are called ‘killers’ for a reason. They’re meat eaters, and it’s hard to know when they’re having a bad day. A pity for this trainer, and all the people watching the show, that this was one of them.

Also, can someone make sure the orcas are having a good day the next time Halle Berry decides to hang out with her close, personal friend Shamu, as she does in the picture below?

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400-Million-Year-Old Mystery: Giant Tree-like Object in Epoch Before Trees Existed

The giant fossil Prototaxites is a big 400-million year old mystery. The fossils resemble tree trunks, and yet they are from a time before trees existed. The stable carbon isotope values are similar to those of fungi, but the fossils do not display structures usually found in fungi. Hence, the enigma.

Prototaxites have sparked controversy for more than a century. Originally classified as a conifer, scientists later argued that it was instead a lichen, various types of algae or a fungus. Whatever it was, it stood in tree-like trunks more than 20 feet tall, making it the largest-known organism on land in its day.

“No matter what argument you put forth, people say, well, that’s crazy. That doesn’t make any sense,” said C. Kevin Boyce, Assistant Professor in Geophysical Sciences at the University of Chicago. “A 20-foot-tall fungus doesn’t make any sense. Neither does a 20-foot-tall algae make any sense, but here’s the fossil.”

Plant-like polymers have been found in the fossils, but nutritional evidence supports heterotrophy, which is not commonly found in plants. These are a few of the confounding factors surrounding the identification of Prototaxites fossils.
Prototaxites existed during the Late Silurian to Late Devonian periods– approximately 420-370 million years ago (ma). Prototaxites fossils have a consistent tubular anatomy, composed of primarily unbranched, non-septate tubes, arranged in concentric or eccentric rings, giving the fossils an appearance similar to that of a cross-section of a tree trunk. The fossil “trunks” vary in size and may be up to 8.8 m long and 1.37 m in diameter, making Prototaxites the largest organism on land during the Late Siluarian and Devonian periods.

Dr. Linda Graham, one of the world’s experts in the evolutionary origin of land plants at the University of Wisconsin, and her colleagues believe that they have resolved this long-standing mystery.

Their hypothesis is that Prototaxites fossils may be composed of partially degraded wind-, gravity-, or water-rolled mats of liverworts that are associated with fungi and cyanobacteria. This resembles the mats produced by the modern liverwort genus Marchantia. The authors tested their hypothesis by treating Marchantia polymorpha in a manner to reflect the volcanically-influenced, warm environments typical of the Devonian period and compared the resulting remains to Prototaxites fossils. Graham and her colleagues investigated the mixotrophic ability of M. polymorpha by assessing whether M. polymorpha grown in a glucose-based medium is capable of acquiring carbon from its substrate.

“For our structural comparative work,” Graham said, “we were extremely fortunate to have an amazing thin slice of the rocky fossil, made in 1954 by the eminent paleobotanist Chester A. Arnold.”

Their structural and physiological studies showed that the fossil Prototaxites and the modern liverwort Marchantia have many similarities in their external structure, internal anatomy, and nutrition. Despite being subjected to conditions that would promote decomposition and desiccation, the rhizoids of M. polymorpha survived degradation, and with the mat rolled, created the appearance of concentric circles. The fungal hyphae associated with living liverworts also survived treatment, suggesting that the branched tubes in fossils may be fungal hyphae. The very narrow tubes in the fossils resemble filamentous cyanobacteria that the researchers found wrapped around the rhizoids of the decaying M. polymorpha.

“We were really excited when we saw how similar the ultrastructure of our liverwort rhizoid walls was to images of Prototaxites tubes published in 1976 by Rudy Schmid,” Graham said.

In their investigations into the nutritional requirements of M. polymorpha, Graham and her colleagues found that the growth of M. polymorpha in a glucose-based medium was approximately 13 times that seen when the liverwort was grown in a medium without glucose. Stable carbon isotope analyses indicated that less than 20% of the carbon in the glucose-grown liverwort came from the atmosphere. The stable carbon isotope values obtained from M. polymorpha grown with varying amounts of cyanobacteria present span the range of values reported for Prototaxites fossils. Taken together, these results demonstrate that the liverworts have a capacity for mixotrophic nutrition when glucose is present and that mixotrophy and/or the presence of cyanobacteria could be responsible for the stable carbon isotope values obtained from Prototaxites.

Graham and her colleagues’ results demonstrate that liverworts were important components of Devonian ecosystems. Their results support previous hypotheses that microbial associations and mixotrophy are ancient plant traits, rather than ones that have evolved recently.

More information: The full article in the link mentioned is available for no charge for 30 days at http://www.amjbot.org/cgi/content/full/97/2/268

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Giant fish swam prehistoric seas

Prehistoric seas were filled with giant plankton-eating fish which died out at the same time as the dinosaurs, new fossil evidence suggests.

Scientists from Glasgow, Oxford and the United States have identified fossil evidence which shows the fish existed between 66 and 172 million years ago.

They believe it may be a “missing piece in the evolutionary story of fish, mammals and ocean ecosystems”.

The findings of the research are published in the journal, Science.

The international team which carried out the study included academics from Glasgow and Oxford Universities, DePaul University in Chicago, Fort Hays University in Kansas and the University of Kansas.

The project began in Glasgow, with a review of the remains of the giant Jurassic fish Leedsichthys, in conjunction with the excavation of a new specimen of this creature in Peterborough.

Scientists viewed Leedsichthys as an isolated example of a giant filter feeder in the oceans during the age of dinosaurs.

But there was a gap in the fossil record between it and the first appearance of modern filter-feeders, some 100 million years later.

Dr Jeff Liston, from Glasgow University, ran the excavation in Peterborough and found the new specimen to be an anomaly.

“The breakthrough came when we discovered additional fossils, similar to Leedsichthys, but from much younger rocks,” he said.

New fossils

“These specimens indicated that there were giant filter-feeding fishes for much longer than we thought.

“We then started to go back to museum collections, and we began finding suspension-feeding fish fossils from all round the world, often unstudied or misidentified.”

Several of the most important new fossils – all from the same extinct bony fish family as Leedsichthys – came from sites in Kansas.

Other remains originated as far afield as Dorset and Kent in the UK, and in Japan.

Dr Liston added: “The fact that creatures of this kind were missing from the fossil record for over 100 million years seemed peculiar.

“What we have demonstrated here is that a long dynasty of giant bony fish filled this space in time for more than 100 million years.

“It was only after these fish vanished from the ecosystem that mammals and cartilaginous fish such as manta rays, basking sharks, whale sharks began to adapt to that ecological role.”

Dr Liston said the findings had “implications for our understanding of biological productivity in modern oceans, and how that productivity has changed over time”.

One of the best preserved Kansas specimens had previously been interpreted as similar to a fanged predatory swordfish.

When members of the team began to clean the specimen, they found a toothless gaping mouth, with an extensive network of thin elongate bony plates to extract huge quantities of microscopic plankton.

The team named this four to five metre-long fish Bonnerichthys, in honour of the Kansas family who discovered the fossil.

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