Ancient tulip-shaped marine creature uncovered in Canada

Tulip Fossil

Burgess Shale found in the Canadian Rockies is an ancient fossil bed that has helped professionals unearth several primitive species. Well, this study by scientists from the University of Toronto examines a new marine creature found in Burgess Shale that apparently lived in the oceans approximately 500 million years ago.

The bizarre creature in question seemed to resemble a tulip flower and was as long as 20cm. It has been named officially as Siphusauctum gregarium. Notably, this marine animal appeared to have possessed a unique filter feeding system. It had a long stem with a bulbous cup-like structure called calyx, around the upper surface that enfolds a different kind of gut and filter feeding system.

This animal would presumably have filtered out substances from water that reached its calyx via small holes. A small disc present at the end of the stem would have secured the critter to the seabed. Moreover, this being seemingly lived in big groups, as indicated by the presence of over 65 individual samples.

“Most interesting is that this feeding system appears to be unique among animals. Recent advances have linked many bizarre Burgess Shale animals as primitive members of many animal groups that are found today, but Siphusauctum defies this trend. We do not know where it fits in relation to other organisms,” commented lead author, O’Brien.

The team unraveled these fossils from a new Burgess Shale location in Canada, which is currently carrying the nickname, ‘The Tulip Beds.’ According to the researchers, this discovery has shed light on the complex form of animals which were prevalent during that time span.

The findings are published in the January 18 issue of the journal, PLoS ONE.

Carbon dioxide may harm brains of fish

Seawater Fish

The harmful effects of carbon dioxide are well known by all, but are they restricted to just human beings? Answering this question, scientists from the University of Oslo have revealed that carbon dioxide emissions are apparently harming the central nervous system of fishes in seawater and this is threatening their survival.

The scientists found that higher levels of carbon dioxide in the water appeared to interfere with the GABA-A receptor, which is a principal molecule in the brain. This receptor is supposedly responsible for the sensory and behavioral capabilities of fishes.

“CO2 concentrations predicted to occur in the ocean by the end of this century will interfere with fishes’ ability to hear, smell, orient and evade predators,” cited Professor Goran Nilsson from the Department of Molecular Biosciences.

Previous studies have shown that higher proportions of carbon dioxide in the sea may expose fishes to predators, as they are not able to locate a reef and smell the peril awaiting them properly. Considering that the aforesaid receptor is universally present, the findings should be a cause for concern.

The involved team is of the opinion that fishes which breathe more of oxygen in the water are at greater risk, as a larger portion of their gills are exposed to the sea. Fishes like tuna and mackerel fall under this category. Also, fishes with dysfunctional GABA-A receptors appeared to lose their innate intuition to keep to the left or right, which could easily bring them to the notice of predators.

By far, the assumption that acidification alone leads to destruction of marine wealth may not be true. This study suggests that the mere presence of carbon dioxide could harm the nervous systems of fishes. The article titled, ‘Near-future CO2 levels alter fish behavior by interfering with neurotransmitter function’ is published in the journal, Nature Climate.

Fishes first started walking on woodlands, says research

Flooded Woodland

The constraints of nature may be capable of altering even deeply hardwired attributes of creatures. Signifying this aspect, experts from the University of Oregon have disclosed a unique theory which suggests how certain fishes got transformed into amphibians.

An extensive trial conducted at various sites indicated that the transitional fossils of fishes were not related to dried ponds or desert locations. Rather, they were found near humid woodland soils which implied that our remote ancestors evolved in an ambience which was moist and warm.

“Judging from where their fossils were found, transitional forms between fish and amphibians lived in wooded floodplains. Our distant ancestors were not so much foolhardy, as opportunistic, taking advantage of floodplains and lakes choked with roots and logs for the first time in geological history,” remarked Gregory J. Retallack, professor of geological sciences.

Gregory Retallack

The scientists believed that limbs were essential to overcome woody barriers while a flexible neck helped the fishes stay in shallow water. However, according to this new hypothesis, the limbs and neck that appear distinctive in salamanders and fish may not have been formed from hardcore adventures in deserts. These body parts would have been nurtured steadily in humid air covering wooded floodplains.

However, detailed scrutiny of transitional fossils across the globe is vital to get an insight into the atmosphere and settings when fishes first showcased their tryst with walking. Similar to this scenario is the Darwin fish of chrome clothed in car trunks which implicated a specific period and location in the lengthy evolutionary history of life on the planet.

The research is published in the Journal of Geology.

Sandeels do not swim if there is no food around: Research

Sandeels

Sandeels are an interesting species of fish which swarm the North Sea during spring and early sunny days. During day time, they are all active searching for copepods, but as the day progresses and darkness sets in, they seemed to be out of sight. A team of scientists from the Technical University of Denmark, have unraveled the mystery surrounding the sudden disappearance of these sandeels.

The scientists found that when sandeels complete their task of foraging, the huge schools were severed and they buried themselves within the sandy seabed. They apparently spent the entire day there and so remained well protected from attackers. In winters, most of the species of sandeels get buried in the sand permanently.

“We make stock assessments based on a combination of how many fish are caught per day in the sandeel fishery and data from our own surveys. The problem is, that catch rates vary heavily from week to week because it is only possible to catch the sandeels that have left the sand, and we do not know how many that is,” remarked postdoc Mikael van Deurs from the National Institute of Aquatic Resources (DTU Aqua) in Denmark.

The findings revealed that sandeels seemingly buried themselves in the sediments based on the availability of food. In some instances, if the sandeels are gifted with foodstuffs, they were ready to even face the risk of being devoured by predators.

Notably, these marine creatures did not supposedly swim when there was no food around. Therefore, when the fish starved for many days, it did not presumably rise from its sandy bottom. This is one of the important findings in the realm of fisheries taking place worldwide.

The research is published in the journal, Marine Biology.

Mystery of disappearing squid solved

Humboldt Squid

The sudden disappearance of the Humboldt squid has been hard to pin down for professionals ever since it happened. A research conducted by biologists at the Stanford University has put forward that the Humboldt squid apparently migrated to different locations in search of food.

The team explored the Sea of Cortez thoroughly and found that there were considerably less squid than those which are present normally. They also seemed to be sexually mature and were spawning at extremely small sizes.

The analysis began when the squid which exists in large numbers were not found in the places they frequent. The experts assumed that the squid were trapped in an adverse situation.

Another mechanism where warm nutrient-poor tropical water from the open ocean flows into the Sea of Cortez and causes the cooler water to move deeper by 150 feet or more underneath the surface, looked like the causal factor for the squid’s migration. This phenomenon is called El Nino.

“Squid can move to an area of tidal upwelling, which remains productive during an El Niño, and continue on their merry, giant-squid lifestyle and live to spawn when they are a year and a half old. Or they can move away from land into an open-ocean environment, where food is less abundant but the supply is steady, as its availability doesn’t depend on upwelling,” commented marine biologist William Gilly.

The cool breeze in the sea areas doesn’t seem to be sufficient for the nutritious water to reach the surface level. Thus, the upwelling instigated by the wind possibly just manages to reuse the warmer water leading all species and creatures depending on the water to death.

El Nino seemingly caused the squid to migrate for better foodstuffs which may have brought them to Midriff islands. In this place, upwelling is driven by tough tides which stays untouched by the warm tropical water.

This research is particularly of interest to fishermen who have been overly concerned about the maintenance of squid fishery.

Fishes save Pacific coral reefs from dying?

Surgeonfish Parrotfish

In the past few years, there has been increasing awareness on the depletion of coral reefs. In yet another example of nature’s interlacing, scientists from the University of California Santa Barbara (UCSB) have found a specific case where fishes have aided coral reefs in recovering from cyclones and predators.

This research was unfolded in the backdrop of the coral reefs in the South Pacific island of Moorea, in French Polynesia. The team found that the health of the latter is apparently shielded by the parrotfish and surgeonfish which consume algae.

“We wanted to know why Moorea’s reefs seem to act differently than other reefs. Specifically, we wanted to know what ecological factors might be responsible for the dramatic patterns of recovery observed in Moorea,” commented Tom Adam, first author, research associate with MCR LTER, and postdoctoral fellow at UCSB’s Marine Science Institute.

Crown Of Thorns Sea Star

Baby fishes, especially herbivores fishes thrived in shrinking reefs as more food is available by means of algae. Thus the survival rate of juvenile parrotfishes and surgeonfishes appeared to rise which regulated the amount of algae found on the fore reef.

Cumulatively, the fishes acted as a multitude of fishy lawnmowers which seemingly crop the algae to optimum levels sufficient for new baby corals to reside onto the reef and develop. This could be one reason why coral reefs in Caribbean that do not have these protective fishes, may not be on the road to recovery.

Coral reefs need healthy populations of parrotfishes and surgeonfishes to maintain the right proportion of algae on the reefs. In the absence of these types of fishes, there is an overgrowth of algae in the reefs that possibly make it tough for corals to re-build themselves.

The analysis is published in the journal, PLoS ONE.

Soaring temperatures threaten marine species: Research

Marine Species

Adaptation holds the key to nature’s bliss, but unfortunately, not everyone appears to be experiencing it. In a research by scientists at Scottish Marine Institute, it has been unraveled that growing heat will apparently cause many species of plants and animals to migrate to different areas and some marine creatures could be left homeless.

The investigators analyzed altering temperatures for land as well as sea of various places spanning from 1960 to 2009. They comprehended the relocation of both terrestrial and marine species to cope with the changing climate. Very meager differences were seen in movement rates at both the surroundings.

Dr Mike Burrows from the Scottish Association for Marine Science elaborated, “When temperatures rise, plants and animals that need a cooler environment move to new regions. The land is warming about three times faster than the ocean so you might simply expect species to move three times faster on land, but that’s not the case.”

In case land temperatures spike, terrestrial creatures have an option to shift to other areas with cooler climatic conditions. But, this seems to be impossible for some marine species which live along the surface of water. Nevertheless, fishes seem to move deep inside the water to find a suitable cooler location, but some marine plants and slow-moving corals may have to go ahead hunting for suitable habitats and could also be snared in a situation where there is absolutely no place to go.

Moreover, warmer temperatures presumably impede growth, reproduction and survival of vital progenies such as fish, corals and sea birds that add to the ecology and economy of the planet. The analysis also outlined that the areas where the species relocate to are important biodiversity hotspots like the coral triangle in South-eastern Asia.

This study will help conservationists be ready for varying temperatures and safeguard coral habitats in the future. It is published in the journal, Science.

Toxic seaweed presumably harms corals

Fijian Coral Reef Every organism on earth struggles for survival and is remotely associated with creatures dwelling in the same location. Extending this view, scientists at Georgia Institute of Technology in Atlanta have spotted and mapped the chemical construct of molecules utilized by a particular species of marine seaweed that apparently restrains the development of reef-building coral.

Experts believe that competition with this macroalgae could be a major contributing factor in the global decline and absence of recovery of coral reefs. Seaweed growth in coral reefs is seemingly resisted by plant-eating fish but has become less in number owing to overfishing in many areas.

Comprehending these hazardous chemicals and the seaweeds that synthesize them may help in developing new strategies to protect the fishes which feed on the most damaging seaweed. Keeping such herbivores safe will help cut the pressure on coral and allow recovery of certain endangered reefs.

“We were able to isolate some of the key molecules responsible for the harmful interactions between seaweed and coral. These molecules are active at very low concentrations, suggesting that they need only to be expressed on the surfaces of the seaweed in minute concentrations to have damaging effects when they are in contact with the coral,” commented Douglas Rasher, a graduate student in the School of Biology at Georgia Tech.

In an initial study, scientists showed that chemicals existing on the surface of seaweed may harm coral. As a follow-up of this research, the team analyzed interactions between 8 distinct species of seaweed and 3 types of corals growing near Fiji Islands. In almost, 79% of the interactions, the seaweed chemicals seemed to have a negative effect on the coral.

Though some of the corals appeared to combat the chemicals, the study essentially reveals that seaweed chemicals are disadvantageous for corals. In the 2010 study, the team found that the seaweed impeded the coral only when their surfaces came in contact with each other.

Therefore, the team inferred that these chemicals were supposedly hydrophobic that dissolved in oil instead of water. After extensive analysis, the investigators selected 4 poisonous molecules for thorough scrutiny. These were namely two from a green alga known as Chlorodesmis fastigiata and two from a red alga known as Galaxaura filamentosa.

Further researches will explore the evolution of such chemicals in seaweeds. The findings are published in the journal Proceedings of the National Academy of Sciences (PNAS).

Sharks were presumably innocent fishes living in freshwaters

Shark Fossils Could the predatory sharks be innocent creatures by any chance? A team of German paleontologists have stumbled upon 230 million-year old fossil egg capsules and tiny teeth from Kyrgyztan which has led them to believe that primitive sharks were harmless fishes living in shallows of freshwater lakes and formed nurseries of their hatchlings.

The research team found the frames of many tiny teeth along with egg capsules that embodied 2 distinct species of shark. One of the species called hybodontids, is related to both teeth and egg capsules while the second species known as xenacanthid is linked to just the egg capsules. The hybodontids are known to have been extinct 65 million years ago like the dinosaurs while the xenacanthids survived till the Triassic, nearly 200 million years back.

“Today, this amazing fossil site is one of the farthest points on land from any sea – quite similar to the situation during the Late Triassic. It was therefore something of a surprise when fossil shark eggs and babies were recently discovered in this area,” commented Sebastian Voigt, one of the authors of the study.

As per the lead author, Jan Fischer, the chemical composition of the tooth enamel apparently shows that the Madygen nursery was unequivocally built in freshwater. This is something not found in modern egg laying sharks which are known to reproduce specifically in the sea.

Fossil sharks are seemingly uncommon. This is partially due to their cartilaginous skeleton which is not conserved in fossil form. The scientists in this research found a spine, tooth, three denticles from a 10kg specimen. Nearly all the miniscule teeth presented tiny juveniles. The team found very few adult teeth. This reveals that recent day sharks like the freshwater ancestors bred in shallow waters. These young ones seemingly lived in these secure regions before they migrated away from the lake shores as they grew.

What remains a mystery for the scientists is the place where the adults moved after spawning. Voigt wishes to know if adult sharks continually lived in freshwaters or transited many kilometers from the sea for expanding their family. If it is true than this may make them similar to the modern day salmon which are known to do the same for the purpose of breeding. This is something which cannot be revealed even by the Madygen deposits.

The research is published in the Journal of Vertebrate Paleontology.

Innovative fishing technique supposedly spreading through dolphins

Dolphin With ConchCan dolphins undertake fishing as well for satisfying their own purposes? Scientists from Murdoch University have revealed that a technique of fishing believed to have been recently documented is apparently spreading among dolphin populations.

These dolphins namely Indo-Pacific bottlenose dolphins found in Shark Bay seemingly engage in what is known as ‘conching’. They ensnare small fishes in large conch shells with their beaks and then get the shells to the surface. They are then known to shake them so that the water filters out and the fishes drop right into their mouths.

“In the last four months alone, the research team have seen and photographed the behaviour no less than six times, possibly even seven. If – and that is a big if – we are witnessing the horizontal spread of this behaviour, then I would assume that it spreads by an associate of a ‘conching’ dolphin closely observing the behaviour and then imitating it,” commented Murdoch Cetacean Research Unit Researcher Simon Allen.

He added that it is a thought-provoking possibility that this action could spread just in front of our eyes in a matter of a field season or two. This suggests that we can also detect the spread. Though observing a specific behavior in dolphins sounds intriguing it also poses questions on how the process of conching happens exactly.The scientists are yet not clear if dolphins track fishes into the protection of the large, empty conch shells or whether they purposely make the shell look big enough for the fishes to find a safe haven and escape from death.

As per Allen, if the team comes across images or videos depicting how the dolphins turn the shells upside down, it would be priceless as it apparently affirms premeditation on their part. He wittingly puts it that such a devilish behavior can be expected from Shark Bay’s bottlenose dolphins. However, he concludes that without any sort of clear-cut evidence it would be too early to reach any inferences.

Florida reefs seemingly unable to bear a chilly episode

Florida Coral Reefs Florida’s 2010 cold snap that surpassed all records had a subsequent effect on the flora and fauna as well and seems to be a matter of concern. A new study by University of Miami Rosenstiel School of Marine & Atmospheric Science scientists reveals that Florida’s corals have also reduced in number due to the cold atmosphere.

The falling temperatures in January apparently led to the most unfortunate loss of corals in the Florida Reef Tract. It runs across 160 miles from Miami to the Dry Tortugas. It seemingly is the lone living barrier reef in the continental U.S.

“It was a major setback. Centuries-old coral colonies were lost in a matter of days,” commented Diego Lirman, associate professor at the UM Rosenstiel School and lead author of the study.

The team undertook a survey of 76 reef sites from Martin County to Key West for a span of 1 month during and shortly after the chilly climate. The investigators compared the death rates of corals due to cold events to the warm-water instances such as the bleaching event in 2005. They found that the cold-water event seemed to cause more mortality than the warm-water issues. The findings revealed that over 40% of many essential reef-building species were apparently killed. Also, huge colony reefs that were shallow and near the banks were seemingly the most severely hit. Contrarily, there appeared to be just 1 percent tissue mortality due to warm-water incidence since the year 2005. Coral species that showed their adaptability to higher-than-normal ocean temperatures probably faced the greatest effect of the cold-water event.

Lirman says that it is undeniably a single worst event on record for Florida corals. Waves of Ice-cold Arctic air slashed into Florida at the onset of the year 2010, when air temperatures touched the bottom to 1°C, while ocean temperatures dropped to 11°C. As per the authors this cold climate apparently caused coral mortality but it also took away their resistance and fighting abilities that will take a series of decades to come back. Florida’s reefs are situated in a marginal location at the northernmost area for coral development. Corals have adjusted to a particular temperature range and normally may not be seen in areas where water temperatures fall below 16°C. Weather alterations, coastal development, pollution, overfishing and diseases have supposedly resulted in stressful surroundings for coral reefs across the globe. The authors cite the importance of ways to enhance the ecosystem like reef restoration, efforts to curb pollution and utility of management tools like marine protected areas. All this would help survival of coral reefs during the forthcoming large-scale upheavals.

Lirman believes that though corals can’t be shielded from drastic conditions, lessening other stresses is much within our scope that will subsequently help them reach normalcy. The paper is titled ‘Severe 2010 Cold-Water Event Caused Unprecedented Mortality to Corals of the Florida Reef Tract and Reversed Previous Survivorship Patterns,’ and is published in the journal PloS One.

Most primal living eel supposedly found

Protoanguilla Palau Eel

Eels that sometimes resemble snakes in appearance are one of the most fascinating creatures of the marine world. And to add to it, researchers at the Smithsonian and partnering organizations have uncovered a prominently primitive eel in a fringing reef away from the coast of the Republic of Palau.

This fish shows up many age-old anatomical attributes that are not known in the other 19 families and above 800 species of existing eels. This apparently sets up another clan evolving from a new genus and family. The species, termed Protoanguilla palau, seemingly replicates most of the physical features of the 19 families of Anguiliformes that are presently living. Some more physical qualities reflecting the primitive age like second upper jaw bone and nearly 90 vertebrae have also been discovered. These were apparently only found in the form of fossils from the Cretaceous era. Other points of observation such as a full set of bony toothed ‘rakers’ in the gill arches are a usual trait in bony fishes. However, they are seemingly not found in fossils or living eels.

Further analysis of the complete mitochondrial DNA show that the aforesaid species embody a primal independent lineage whose evolutionary past seems to be relative to the whole set of living and fossil eel species.

“The equivalent of this primitive eel, in fishes, has perhaps not been seen since the discovery of the coelacanth in the late 1930s. We believe that such a long, independent evolutionary history, dating back to the early Mesozoic (about 200 million years ago), retention of several primitive anatomical features and apparently restricted distribution, warrant its recognition as a living fossil,” remarked Dave Johnson, ichthyologist at the Smithsonian’s National Museum of Natural History and lead author of the team’s research.

Anguilliformes are a separate set of bony fishes that debuted in the fossil record around 100 million years ago. As time passed, they lost their pelvic fins while their dorsal, anal and caudal fins prolonged. Living eels are apparently found in diversified locations ranging from shallow coastal waters to the deep open ocean. This analysis was conducted from just 10 samples gathered from a cave in Palau highlighting the importance of conservation of the species. Johnson concludes that this enthralling new species outlines that there is so much more to explore on Earth.

The research is published in the August 17 issue of the Proceedings of the Royal Society B.

Gray whales presumably survived the glaciers by altering their diet

Gray Whale Feeding

After we saw the homecoming of the South Right whale, fresh data about the gray whale has stepped in. According to a research by University of California, Berkeley, and Smithsonian Institution paleontologists, gray whales that have faced many cycles of global cooling and warming over millions of years have done so apparently due to their varied diet that differs from what they consume now.

The researchers analyzed the California gray whale in the study. Scientists believe that there were larger numbers of whales in the past, which was apparently because they consumed a broad range of foodstuffs that whales in today’s world have just begun to feed on. Gray whales seem to consume bottom-dwelling benthic organisms by sucking sediments and eliminating the worms and crustaceans. Presently some whales also seem to consume herring and krill much like their baleen ancestors like humpback and blue. Some whales have seemingly given up on the migratory race as well. One set moves around year-round off Vancouver Island in Canada, where they catch herring and krill.

“There almost certainly were higher gray whale populations in the past. We propose that gray whales survived the disappearance of their primary feeding ground by employing generalist filter-feeding modes, similar to the resident gray whales found between northern Washington State and Vancouver Island. A combination of low population numbers and a species migrating between places where humans didn’t bother them gave us the impression that gray whales have a stereotypical migratory and feeding behavior that may not be historically correct,” remarked evolutionary biologist David Lindberg, a UC Berkeley professor of integrative biology who coauthored the paper with his former student, Nicholas D. Pyenson, now curator of fossil marine mammals at the Smithsonian in Washington, D.C.

As per a 2007 estimate, the California gray whale population was supposedly 76,000 to 120,000 before humans began killing them. Scientists claim that the gray whales are survivors. They apparently have high levels of evolutionary plasticity that will make them live in the climate change which is bound to happen in the following few centuries. The weather conditions may also raise the sea levels to certain meters.

The researchers wished to inspect a period called the Pleistocene that might help them comprehend their adaptability to climate change in present days. According to Lindberg, just the marine arena survived the last glacial cold spell that affected all flora and fauna years ago. Their objective was to study the eastern and the California gray whale along with its 120.000 year old past when there was a climate shift from warm to glacial and finally the warm climate that we experience today. Almost 60percent of the Bering Sea platform was crushed during the transition. It seems surprising how the gray whale managed to refrain from extinction if they were essentially living on the Bering platform.

By measuring the proportion of food lost because of falling sea levels, and adding it to the estimates of the food required to keep a whale alive, researchers gauged the effect of global cooling on the gray whales. Scientists believe that the population may have had to utilize alternative feeding modes enough to carry on a populace of nearly 70,000 in the warm periods so that the depletion in the glacial periods wouldn’t be less below 5000-10,000 whales. Lower levels would indicate bottleneck in the DNA of whales which has not been possibly found. Finally, the investigators conclude that when surroundings disappear in glacial maxima, ecological past of all the organisms dwelling in the Bering Sea may be a matter well thought over.

The findings appear online in the open-access journal PLoS ONE.

Fishes and mammals chew in seemingly different ways with tongue muscles

Jaw, Tongue And Teeth

Chewing techniques in mammals and fishes have evolved differently from each other according to a new study conducted by Brown University. The scientists studied the muscles which controlled the jaw and tongue movement of fishes and mammals. They said that the difference in chewing showed that animals have seemingly changed their manner of chewing and digesting and that evolution may have a role to play in this change.

They discovered that mammals employed their tongue muscles to position food in such a way that jaw muscles used the teeth in the best manner to chew on food. While fishes used the same to mainly funnel the food farther inside their mouths for processing.

Nicolai Konow, a postdoctoral researcher at Brown and the lead author on the study, published in the journal of Integrative and Comparative Biology states, “It’s pretty clear that all these animals chew, but the involvement of the tongue in chewing differs. And that brings up the question of what the muscles associated with the tongue and the jaw are doing.”

Nicolai Konow along with his colleagues published papers last year as well as in 2008, which illustrated the chewing methods of pike, bowfin and fish with tiny teeth on their tongues like salmon and osteoglossomorphs. These researchers showed that in some species, the chewing process began with the tongue positioned in the upper mouth. Following this, the fish fires a muscle called sternohyoid downward, retracting the tongue inward, and then moving it forward and upward again to its first position in the upper mouth. From the left side of a fish, this cycle looks like an ellipse tilted at an angle with its tongue moving in a clockwise direction.

This discovery was boosted by previous researchers’ studies which showed a similar cycle of chewing in other fishes like gar, bichir and lungfish. The muscles of pigs, alpacas and goats were studied by Konow and his team to determine the chewing techniques of mammals. The animals had electrodes attached inside their jaw and tongue muscles. It was found that as they started chewing, their tongues were pushed forward and upward, and then went back to their first position. With the animals facing left, the tongue makes an ellipse in an anti-clockwise direction per cycle.

Konow opined that in fishes, the tongue send the food quickly in and through the mouth, although in many species an extra set of jaws would have grinded the food. Also their tongue aids the fishes in breathing by transferring oxygenated water via their mouth to their gills. “That’s why you want to constantly have that inward movement with the tongue.” explained Konow.

On the other hand mammals utilize their tongues to enhance chewing by setting their food on the right spot in their mouth. However distinction between closely related species was also discovered. Goats, alpacas and such herbivores were less coordinated in their chewing than omnivores like pigs. Defying popular belief, the cud-chewing animals weren’t as monotonously rhythmic in their chewing.

Konow, expressing surprise commented, “It is a puzzling finding. We think the herbivore needs the bolus (the soft mass of chewed food) to be in a precise place between each chew. So the tongue may be constantly moving around to make sure the bolus is in the right place between chews.”

To find out where, when and with which species the distinction in chewing emerged was the next task. A study conducted by Anthony Herrel, a Belgian biologist, previously showed that similar to mammals, lizards thrust their tongues forward and upward as they started chewing. The researchers felt that the transition is likely to have happened among amphibians. According to Konow though amphibians still reproduce in water, there are some which have become completely terrestrial. He plans to study amphibian chewing systems next.

Plastic found in more than 9% north Pacific fishes, says Scripps study

Scripps Study Garbage Patch

A study conducted by two graduate students of the Scripps Environmental Accumulation of Plastic Expedition (SEAPLEX) revealed the extent of water and environment pollution caused by man. According to the study, during the voyage undertaken to the North Pacific Subtropical Gyre, more than nine percent of fishes collected had plastic waste in their stomach. That area of the ocean has been named as the ‘Great Pacific Garbage Patch.’

The graduate students, Rebecca Asch and Peter Davison, deduced through their study that every year fishes of the north area of the Pacific Ocean swallow plastic at a rate of about 12,000 -to 24,000 tons. For this research, a group of graduate students travelled aboard the Scripps research vessel-New Horizon, to more than 1,000 miles west of California to the eastern area of the North Pacific Subtropical Gyre. The voyage lasted for roughly more than 20 days and was undertaken in August 2009. During this time, water samples, marine debris and specimens of fish were gathered ranging from the surface, to thousands of feet deep within the sea.

Approximately 9.2 percent of the 141 fishes spanning 27 species which were dissected for the study had plastic debris in their stomachs. The researchers say that the debris found inside the mid-water fishes were broken down into tiny pieces which were smaller than a fingernail. They were so small that their source could not be identified.

“About nine percent of examined fishes contained plastic in their stomach. That is an underestimate of the true ingestion rate because a fish may regurgitate or pass a plastic item, or even die from eating it. We didn’t measure those rates, so our nine percent figure is too low by an unknown amount,” stated Davison.

The author says that, studies conducted on fish and plastic ingestion previously may have featured “net-feeding” biases. Net feeding can result in artificially high cases of plastic consumption by fishes while they are confined to a net which has large amounts of debris. But this study by Scripps was apparently modeled to steer clear of such biases. A surface collecting device called manta net, which sampled for fifteen minutes at one time, collected the highest amount of plastic. Because of the short sampling time, the risk of net feeding is almost eliminated since the amount of time that a fish spends in the net is decreased and plastic does not accumulate in huge numbers.

Explained James Leichter, a Scripps associate professor of biological oceanography who participated in the SEAPLEX expedition, “This study clearly emphasizes the importance of directly sampling in the environment where the impacts may be occurring. We are seeing that most of our prior predictions and expectations about potential impacts have been based on speculation rather than evidence and in many cases we have in fact underestimated the magnitude of effects. SEAPLEX also clearly illustrates how relatively small amounts of funding directed for novel field sampling and work in remote places can vastly increase our knowledge and understanding of environmental problems.”

Since this research only concentrated on the prevalence of plastic ingestion, topics like the composition of plastic or the toxicological impacts on fishes were not included. Out of the 141 fishes, most of them were myctophids which are more commonly known as lanternfish owing to their luminescent tissue. At daytime these fishes stay between 200-1,000meters below the surface of the sea while at night they come up to the surface.

Asch commented, “These fish have an important role in the food chain because they connect plankton at the base of the food chain with higher levels. We have estimated the incidence at which plastic is entering the food chain and I think there are potential impacts, but what those impacts are will take more research.”

The marine debris are scattered across thousands of miles of the North Pacific Subtropical Gyre. For obtaining dimensions and boundaries of the garbage patch, researchers gathered samples in 132 net tows (of which 130 contained plastic) spanning a distance of more than 2,375 kilometers. This was done because it is not possible to map the debris from either air or space. This patch or region full of waste congregations is normally shunned by mariners because of its calm winds and mild currents. Since the North Pacific Subtropical Gyre hasn’t been examined in detail, several questions regarding the marine debris in the area and its effects in the long run on the marine environment remain unanswered as of today.

The results of this study were printed in a journal called the Marine Ecology Progress Series.