The Monterey Bay Aquarium Research Institute (MBARI) have developed an aquatic robot capable of collecting algal cells from the ocean and extracting the genetic information needed to identify them. The robot, which can accurately be described as a seafaring mobile analytical laboratory, can also extract toxins from the algae samples, thereby allowing scientists to assess the risk to humans and wildlife.

The MBARI-designed robot, formally known as the Environmental Sample Processor, or ‘ESP,’ for short, has now been successfully used by scientists from NOAA’s National Centers for Coastal Ocean Science to conduct the first remote detection of an algal species and its toxin below the ocean’s surface.

The global distribution, frequency, duration and severity of harmful algal blooms are believed to be on the increase and the new robot will make it much easier for scientists to assess the situation and relay accurate information to coastal managers and public health officials.

“Our public health monitoring program is one of the many groups that can benefit directly from the ESP technology and ability to provide an early warning of impending bloom activity and toxicity,” said Gregg Langlois, director of the state of California’s Marine Biotoxin Monitoring Program. “This is critical information for coastal managers and public health officials in mitigating impacts on the coastal ecosystem, since the toxicity of these algae can vary widely from little or no toxicity to highly toxic.”

The information obtained by ESP is transmitted to the laboratory via radio signals.

More details about the project can be found in the June issue of the journal Oceanography.

Pictures by mbari

Two species of Asian mouse-deer have been observed utilizing a very interesting technique to get away from predators; they jump into the water and stay there until its safe to come up. By carefully swimming up to the surface to breathe now and then they can stay submerged for long periods of time.

People living in the Indonesian country side have always claimed that deer hide in the water when chased by their dogs, but it wasn’t until the behaviour was observed by a team of scientists doing a biodiversity survey that it caught the attention of the larger scientific community.

In June 2008, the team visited the northern Central Kalimantan Province in Borneo, Indonesia where they suddenly spotted a mouse-deer swimming in a forest stream. When the deer understood that it was being watched by humans, it went below the surface and remained hidden. Over the next hour, team members could see it come to the surface four or five times. Although it probably went up for air a few more times without being noticed, it could clearly remain submerged for more than five minutes at a time.

Eventually, the researchers caught the animal and photographed it before releasing it back into the wild unharmed. It was a pregnant female deer.

One of the members of the team is the wife of Erik Meijaard, a senior ecologist working with the Nature Conservancy in Balikpapan, Indonesia. When she showed her husband the photograph, he identified it as a Greater mouse-deer (Tragulus napu).

That same years, another group of observers witnessed a Mountain mouse-deer (Moschiola spp) throwing itself into pond and swimming under water to get a way from a hungry mongoose in Sri Lanka. The mongoose followed it into the pond, but eventually retreated as the deer continued to stay submerged.

“It came running again and dived into the water and swam underwater. I photographed this clearly and it became clear to me at this stage that swimming was an established part of its escape repertoire,” says Gehan de Silva Wijeyeratne, who saw the incident.

“Seeing it swim underwater was a shock”, he says. “Many mammals can swim in water. But other than those which are adapted for an aquatic existence, swimming is clumsy. The mouse-deer seemed comfortable, it seemed adapted.”

Both incidents have now been described in the journal “Mammalian Biology”.

“This is the first time that this behaviour has been described for Asian mouse-deer species,” says Meijaard. “I was very excited when I heard the mouse-deer stories because it resolved one of those mysteries that local people had told me about but that had remained hidden to science.”

What is a mouse deer?

Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Artiodactyla
Family: Tragulidae

Mouse deer are small deer-like animals with large upper canine teeth. In male specimens you can even see the teeth project down either side of the lower jaw. Ten different species of mouse-deer have been described by science and all except one live in South-East Asia. The Water Chevrotain (Hyemoschus aquaticus) is the only mouse deer native to the African continent and it is also the largest member of the family.

The Water Chevrotain (Hyemoschus aquaticus) lives in swampy habitats and is known to dash into the nearest river as soon as it is spooked by something. Until recently, this was the only mouse deer in which the habit of swimming under water and staying submerged for long periods of time had been described and all the Asian members of the family Tragulidae were thought to be strictly dry-land animals.

One of the most controversial environmental issues of the past decade now seems to have been solved thanks to the consolidated efforts of one U.S. and one U.K. researcher.

In the late 1980s and early 1990s, researchers started getting reports of numerous deformed wild frogs and toads. Many of them missed a limb partly or completely, while others – even more strikingly – had extra legs or extra arms.

The reason behind the deformities became a hot-potato, with some people suspecting chemical pollution or increased UV-B radiation (brought on by the thinning of the ozone layers), while others leaned towards predators or parasites.

“There was a veritable media firestorm, with millions of dollars of grant money at stake,” says Stanley Sessions, an amphibian specialist and professor of biology at Hartwick College, in Oneonta, New York.
Eventually, professor Sessions and other researchers managed to show that many amphibians with extra limbs were actually infected by small parasitic flatworms called Riberoria trematodes. These nematodes burrow into the hindquarters of tadpoles and rearrange the limb bud cells. This interferes with limb development, and in some cases the result is an extra arm or leg.

While these findings explained the conspicuous presences of additional limbs, it wasn’t enough to solve the mystery of the leg- and armless amphibians.

“Frogs with extra limbs may have been the most dramatic-looking deformities, but they are by far the least common deformities found,” Sessions explains. “The most commonly found deformities are frogs or toads found with missing or truncated limbs, and although parasites occasionally cause limblessness in a frog, these deformities are almost never associated with the trematode species known to cause extra limbs.”

To investigate the conundrum, Sessions teamed up with UK researcher Brandon Ballengee of the University of Plymouth. As a part of a larger research project, the two scientists placed tadpoles in aquariums and added various predators to see if any of them could be responsible for this type of injuries.

As it turned out, three different species of dragonfly nymph happily attacked and nicked of the hind legs of the tadpoles; feasting on the tasty legs without actually killing the tadpoles.

“Once they grab the tadpole, they use their front legs to turn it around, searching for the tender bits, in this case the hind limb buds, which they then snip off with their mandibles,” says Sessions. “Often the tadpole is released […],” says Sessions. “If it survives it metamorphoses into a toad with missing or deformed hind limbs, depending on the developmental stage of the tadpole.”

Eating just a leg instead of trying to kill the entire tadpole is beneficial for the dragonfly, since tadpoles develop poison glands in their skin much earlier than those in their hind legs.

Through surgical experiments, Sessions and Ballengee confirmed that losing a limb at a certain stage of a tadpole’s life can lead to missing or deformed limbs in the adult animal. Really young tadpoles are capable of growing a new limb, but they loose this ability with age.

Sessions stresses that the results of his study doesn’t completely rule out chemicals as the cause of some missing limbs, but says that this type of “selective predation” by dragonfly nymphs is now by far the leading explanation.

“Are parasites sufficient to cause extra limbs?,” he asks. “Yes. Is selective predation by dragonfly nymphs sufficient to cause loss or reduction of limbs. Yes. Are chemical pollutants necessary to understand either of these phenomena? No.”

You can find Sessions and Ballengee’s study in the Journal of Experimental Zoology Part B: Molecular and Developmental Evolution.

You have probably noticed it if you’ve ever tried to catch a fish using your bare hands or a small net: the uncanny ability of these creatures to escape, sometimes even before you make a move. Most fish species are incredibly fast and seem to be virtual mind-readers when it comes to predicting when and where you will make your next attempt.

The reason behind this remarkable talent is a special circuit present in the brains of many species of fish. Fish ears constantly sense the sound pressure on each side of the body and if the ear on one side detects a disturbance, the muscles of the fish will automatically bend the body into a c-shape facing the opposite direction. This involuntary reaction makes it possible for the fish to start swimming way from harms way as quickly as possible. Scientists call it C-start and it is highly advantageous when escaping from predators. That is, until you venture upon the Tentacled snake (Erpeton tentaculatum) of South-East Asia.

While studying the Tentacled snake, Kenneth Catania, associate professor of biological sciences at Vanderbilt University, realized that this snake has found a way of exploiting the C-start reflex to its advantage.

Using video recordings of snake (see below) and prey Catania was able to slow down the chain of events enough to make them noticeable for a human eye, and what he saw amazed him. Instead of fleeing from the snake, fish would swim right into the mouth of the predator nearly four times out of five. How could this be?

When hunting, the Tentacled snake forms its body into a peculiar J-shape with its head at the bottom of the “J”. It then remains absolutely still until suitable prey ventures close enough to the “hook”-area of the J. When it finally strikes, it rarely misses since the fish seem to be magically drawn to the jaws of their attacker. In 120 attacks carried out by four different snakes, Catania observed no less than 78 percent of the fish turning toward the snake’s head instead of swimming away from it.

Catania also noticed something else: before the snakes moved their head to strike, they always flexed a point midway down the body. A hydrophone placed in the aquarium unveiled that by flexing its body, the snake produces sound waves intense enough to trigger the fish’s C-start reflex, and since the sound comes from a spot opposite the head of the hungry snake, the C-start reflex forces the fish to turn and swim directly towards the snake’s mouth.

“Once the C-start begins, the fish can’t turn back,” Catania explained. “The snake has found a way to use the fish’s escape reflex to its advantage. I haven’t been able to find reports of any other predators that exhibit a similar ability to influence and predict the future behavior of their prey,”

The C-start behaviour is actually so predictable that the snake doesn’t even bother to aim for the initial position of its prey and then adjust its direction as most predators would. Instead, it goes directly for the spot where it knows the fish will be heading.

“The best evidence for this is the cases when the snake misses,” says Catania. “Not all the targeted fish react with a C-start and the snake almost always misses those that don’t react reflexively.”

Kenneth Catania studies the brains and behaviour of species with extreme specializations. His new snake study is published this week in the online early edition of the journal Proceedings of the National Academy of Sciences.

“Small fish may have small brains but they still have some surprising cognitive abilities”, says Dr Jeremy Kendal* from Durham University’s Anthropology Department.

Dr Kendal is the lead author of a new study showing that Nine-spined stickleback fish (Pungitius pungitius) can compare the behaviour of other sticklebacks with their own experience and make choices that lead to better food supplies.

“‘Hill-climbing’ strategies are widely seen in human society whereby advances in technology are down to people choosing the best technique through social learning and improving on it, resulting in cumulative culture”, says Dr Kendal. “But our results suggest brain size isn’t everything when it comes to the capacity for social learning.”

Around 270 Nine-spined sticklebacks were caught from Melton Brook in Leicester using dip nets. After being divided into three experimental groups and one control group, the fish were housed in different aquariums and the fish in the experimental groups were subjected to two different learning experiences and two preference tests in a tank with a feeder placed at each end.

1.) The fish were free to investigate both feeders during a number of training trials. One feeder (dubbed “rich feeder”) always handed out more worms than the other one (dubbed “poor feeder”). The fish were then tested to see which feeder they preferred.
2.) In the second training trail, those fish that come to prefer the rich feeder could see other fish feeding. During this stage, the rich and poor feeders were swapped around and the rich feeder either gave even more worms than before or roughly the same or less. During the second test, the fish were once again free to explore the tank and both feeders. Around 75 per cent of the Nine-spined sticklebacks had learned from watching the other fish that the rich feeder, previously experienced first hand themselves as the poor feeder, gave them more worms. In comparison, significantly fewer sticklebacks favoured the feeder that appeared to be rich from watching other sticklebacks if they themselves had experience that the alternative feeder would hand out roughly the same or more worms.

Further testing showed that the sticklebacks were more likely to copy the behaviour of fast feeding fish.

“Lots of animals observe more experienced peers and that way gain foraging skills, develop
food preferences, and learn how to evade predators”, Dr Kendal explained. “But it is not always a recipe for success to simply copy someone. Animals are often better off being selective about when and who they copy. These fish are obviously not at all closely related to humans, yet they have this human ability to only copy when the pay off is better than their own.”

The study, which has been published in the journal Behavioral Ecology, was carried out by scientists from St Andrews and Durham universities and funded by the Biotechnology and Biological Sciences Research Council. The lead author of the study, Dr Kendal, is a Research Council UK Fellow.

In an effort to end the country’s reliance on imported uranium, Dr Masao Tanada of the Japan Atomic Energy Agency has developed a fabric capable of absorbing uranium directly from seawater.

“At the moment, Japan has to rely on imports of uranium from Canada and Australia, but this technology could be commercially deployed in as little as five years,” says Tanada.

In Canada and Australia, the uranium is extracted in conventional mining operations which are expensive and damaging to the environment.

Dr Tanada is now hoping to secure funding to set up a 400 square mile underwater “uranium farm” consisting of anchored sponges made from the new material; a fabric composed primarily of irradiated polyethylene.

The world’s oceans contain an estimated 4.5 billion tons of uranium; roughly 3.3 parts per billion. Japan uses 8,000 tons of uranium per annum; an amount that Dr Tanada says could be harvested from the Kuroshio Current that flows along Japan’s eastern seaboard. His proposed 400 square mile farm would on its own supply Japan with roughly one-sixth of what it needs to run its nuclear power stations.

The famous Sharktooth Hill Bone Bed near Bakersfield has tantalized the imagination of scientists and laymen alike since it was first discovered in the 1850s. How did a six-to-20-inch-thick layer of fossil bones, gigantic shark teeth and turtle shells three times the size of today’s leatherbacks come to be?

Was this a killing ground for C. megalodon, a 40-foot long shark that roamed the seas until 1.5 million years ago? Perhaps a great catastrophe like a red tide or volcanic eruption led to animal mass-death in the region? Or is this simply the result of Sharktooth Hill being used as a breeding ground for generations of marine mammals throughout the millennia?

A research team consisting of palaeontologists from the United States and Canada are now offering their take on the Bone Bed, suggesting it is not the result of a sudden die-off or a certain predator. Instead, the North American team sees it as a 700,000-year record of normal life and death, kept free of sediment by unusual climatic conditions between 15 million and 16 million years ago.

The research team bases its hypothesis on a new and extensive study of the fossils and the geology of Sharktooth Hill. Roughly 3,000 fossilized bone and teeth specimens found in various museums, including the Natural History Museum of Los Angeles County (NHM) and UC Berkeley’s Museum of Paleontology (UCMP), have been scrutinized, and the researchers also cut out a meter-square section of the bone bed, complete with the rock layers above and below.

“If you look at the geology of this fossil bed, it’s not intuitive how it formed,” says Nicholas Pyenson, a former UC Berkeley graduate student who is now a post-doctoral fellow at the University of British Columbia. “We really put together all lines of evidence, with the fossil evidence being a big part of it, to obtain a snapshot of that period of time.”

The existence of a 700,000-year window through which we can catch a glimpse of the past is naturally magnificent news for anyone interested in evolution and Earth’s history.

When the Central Valley was a sea

When the Sharktooth Hill Bone Bed formed between 15,900,000 and 15,200,000 years ago, the climate was warming up, ice was melting and the sea level was much higher than today. What is today California’s Central Valley was an inland sea with the emerging Sierra Nevada as its shoreline.

After closely examining the geology of the Sharktooth Hill area, the research team was able to confirm that it had once been a submerged shelf inside a large embayment, directly opposite a wide opening to the sea.

Several feet of mudstone interlaced with shrimp burrows is present under the bone bed, which is typical of ocean floor sediment several hundred to several thousand feet below the surface. Inside the bone bed, most of the bones have separated joints, indicating that they have been scattered by currents.

“The bones look a bit rotten, as if they lay on the seafloor for a long time and were

abraded by water with sand in it“, says UC Berkeley integrative biology professor Jere Lipps.

Many bones also had manganese nodules and growths on them, something which can form when bones sit in sea water for a long time before they are covered by sediment. According to the team, the most likely explanation for this is that the bones have lain exposed on the ocean floor for 100,000 to 700,000 years while currents have carried sediment around the bone bed. The prevailing climatic conditions at the time have made it possible for the bones to accumulate in a big and shifting pile at the bottom of the sea.

“These animals were dying over the whole area, but no sediment deposition was going on, possibly related to rising sea levels that snuffed out silt and sand deposition or restricted it to the very near-shore environment,” says Pyenson. “Once sea level started going down, then more sediment began to erode from near shore.”

The team discards the breeding-ground hypothesis due to the scarcity of remains from young and juvenile animals. Hungry Megalodon sharks being the main contributors to the bone pile is also unlikely, since few bones bear any marks of shark bites. If the bone bed was the result of mass-death caused by an erupting volcano the absence of volcanic ash in the bed would be very difficult to explain, and the presence of land animals like horses and tapirs that must have washed out to sea make the red-tide hypothesis equally thin.

Amazing remains from the past

The Sharktooth Hill Bone Bed covers nearly 50 square miles just outside and northeast of Bakersfield in California and is one of the richest and most extensive marine deposits of bones in the world. Studied parts of the bone bed average 200 bones per square meter, most of them larger bones. Ten miles of the bed is exposed, and the uppermost part of the bed contains complete, articulated skeletons of whales and seals.

Within the bone bed, scientists have found bones from many species that are now extinct and the bed provides us with invaluable information about the evolutionary history of whales, seals, dolphins, and other marine mammals, as well as of turtles, seabirds and fish. Sharktooth Hill is naturally the sight of some impressive shark findings too, including shark teeth as big as a hand and weighing a pound each.

A small portion of the bone bed was added to the National Natural Landmark registry in 1976 but the rest is in dire need of protection.

A collaborative effort

The research team, who’s study will be published in the June 2009 issue of the journal

Geology, consisted of:

– UC Berkeley integrative biology professor Jere Lipps, who is also a faculty curator in UC Berkeley’s Museum of Paleontology.

– Nicholas Pyenson, a UC Berkeley Ph.D who is now a post-doctoral fellow at the University of British Columbia.

– Randall B. Irmis, a UC Berkeley Ph.D who is now an assistant professor of geology and geophysics at the University of Utah.

– Lawrence G. Barnes, Samuel A. McLeod, and Edward D. Mitchell Jr., three UC Berkeley Ph.D’s who are now with the Department of Vertebrate Paleontology at the Natural History Museum of Los Angeles County.

The intricate symbiotic relationship between reef building corals and algae seem to rely on a delicate communication process between the algae and the coral, where the algae is constantly telling the coral that the algae belongs inside it, and that everything is fine. Without this communication, the algae would be treated as any other invader, e.g. a parasite, and be expelled by the coral’s immune system.

Researchers now fear that increased water temperature will impair this communication system, something which might prove to be the final blow for corals already threatened by pollution, acidification, overfishing, dynamite fishing, and sedimentation caused by deforestation.

According to a new report, a lack of communication is likely to be the underlying cause of coral bleaching and the collapse of coral reef ecosystems around the world.

Reef building corals can defend themselves and kill plankton for food, but despite this they can not survive without the tiny algae living inside them. Algae, which are a type of plants, can do what corals can’t – use sunlight to produce sugars and fix carbon through photosynthesis.

“Some of these algae that live within corals are amazingly productive, and in some cases give 95 percent of the sugars they produce to the coral to use for energy,” said Virginia Weis, a professor of zoology at Oregon State University. “In return the algae gain nitrogen, a limiting nutrient in the ocean, by feeding off the waste from the coral. It’s a finely developed symbiotic relationship.

If this relationship were to collapse, it would be death sentence for the reef building corals.

Even though the coral depends on the algae for much of its food, it may be largely unaware of its presence, said Weis. We now believe that this is what’s happening when the water warms or something else stresses the coral – the communication from the algae to the coral breaks down, the all-is-well message doesn’t get through, the algae essentially comes out of hiding and faces an immune response from the coral.”

This internal communication process, Weis said, is not unlike some of the biological processes found in humans and other animals.

Researchers now hope that some of the numerous species of reef building corals found globally and their algae will be more apt at handling change.

“With some of the new findings about coral symbiosis and calcification, and how it works, coral biologists are now starting to think more outside the box,” Weis said. “Maybe there’s something we could do to help identify and protect coral species that can survive in different conditions. Perhaps we won’t have to just stand by as the coral reefs of the world die and disappear.”

The new research has been published in the most recent issue of the journal Science and was funded in part by the U.S. National Science Foundation.

For the first time in history, scientists* have succeeded in measuring the physiology of marine phytoplankton through satellite measurements of its fluorescence. With this new tool, it will become possible for researchers to continuously keep an eye on the ocean’s health and productivity. Since it is based on satellite images the method works all over the world.

“Until now we’ve really struggled to make this technology work and give us the information we need,” says Michael Behrenfeld, an Oregon State University professor of botany. “The fluorescence measurements allow us to see from outer space the faint red glow of tiny marine plants, all over the world, and tell whether or not they are healthy. That’s pretty cool.”

Knowing how the world’s phytoplankton populations are doing doesn’t only tell us about the plankton it self; it also provides us with valuable clues that can help us assess a long row of other processes on the planet. By studying phytoplankton, it is for instance possible to learn about climate change and desertification.

* The break through is the result of the successful collaboration of Oregon State University, the NASA Ocean Biology and Biogeochemistry Program, the NASA Goddard Space Flight Center, University of Maine/Orono, University of California/Santa Barbara, University of Southern Mississippi, Woods Hole Oceanographic Institution, Cornell University, and the University of California/Irvine.

North Carolina State University engineers have created a non-toxic ship hull coating that resists the build up of barnacles.

Barnacles that colonize the hull of a ship augment the vessel’s drag which in turn increases fuel consumption. After no more than six months in salt water, the fuel consumption of a ship has normally swelled substantially, forcing the ship owner to either spend more money on fuel or to remove the ship from the water and place it in a dry dock where it can be cleaned. Both alternatives are naturally costly, and for many years ship owners fought barnacles by regularly coating ship hulls with substances toxic to barnacles. Unsurprisingly, these substances turned out to be toxic to a wide range of other marine life as well, including fish, which caused most countries to ban their use.

Ships are not the only ones colonized by barnacles. In the wild, it is common to see barnacles attached to a wide range of marine species, such as whales and sea turtles. One type of animal is however usually free of barnacles: the sharks. Unlike the smooth-skinned whales, sharks tend to have rough and uneven skin, and this might prove to be the salutation for ships as well.

The new hull coating created by Dr. Kirill Efimenko, research assistant professor in the Department of Chemical and Biomolecular Engineering, and Dr. Jan Genzer, professor in the same department, contains nests of different-sized “wrinkles” which makes the surface rough and uneven, just like the skin of a shark.

The wrinkly material was tested in Wilmington, N.C and remained free of barnacles after 18 months of exposure to seawater. Flat coatings made of the same material were on the other hand colonized by barnacles within a month.

“The results are very promising,” says Efimenko. “We

are dealing with a very complex phenomenon. Living

organisms are very adaptable to the environment, so

we need to find their weakness. And this hierarchical

wrinkled topography seems to do the trick.”

Efimenko and Genzer created the wrinkles by stretching a rubber sheet, exposing it to ultra-violet ozone, and then relieving the tension, causing five generations of “wrinkles” to form concurrently. After that, the coating was covered in an ultra-thin layer of semifluorinated material.