Fishes saving coral


This video says about itself:

BBC ‘Blue Planet – Deep Trouble’ team explain the environmental dangers facing the world’s shallow waters. With high demands for rare species of fish, coral reefs are in danger of being fished out and deserted.

From Discover Magazine:

Coral Call for Help and Fish Swim to the Rescue

When coral are threatened by encroaching toxic algae, they do not have the luxury of running from their enemy. That is not to say these stationary creatures are defenseless, though. Acropora coral has evolved to emit a chemical call for help, and within minutes, a goby fish will show up on the scene, ready to nibble off the algae. Researchers recently discovered this underwater partnership in the waters near Fiji. They say this symbiotic relationship is the first known example of a species chemically signaling another in order to remove a competitor species.

The fish’s response time is short because the goby fish are never far away from the coral. Nestled in the crevices of the reef, protected from predators, goby fish feast on a smörgåsbord of local fares: coral mucus, algae and zooplankton. In return, the goby is available for minor coral maintenance issues like mowing the toxic algae lawn. This task is pretty simple for the fish—one species of goby observed in this study ate the stuff and another just trimmed it off—and important for the coral.

For a tenant-landlord-style relationship, this one’s pretty amicable.

See also here.

New reef coral discovery


This is the new coral species living on the ceilings of caves in tropical coral reefs. Credit: Dr. Bert W. Hoeksema / Naturalis

From EurekAlert!:

A new cave-dwelling reef coral discovered in the Indo-Pacific

Coral named Leptoseris troglodyta sheds light on coral-algal symbiosis

Coral specialist Dr. Bert W. Hoeksema of Naturalis Biodiversity Center in Leiden, The Netherlands, recently published the description of a new coral species that lives on the ceilings of caves in Indo-Pacific coral reefs. It differs from its closest relatives by its small polyp size and by the absence of symbiotic algae, so-called zooxanthellae. Its distribution range overlaps with the Coral Triangle, an area that is famous for its high marine species richness. Marine zoologists of Naturalis visit this area frequently to explore its marine biodiversity.

Reef corals in shallow tropical seas normally need the symbiotic algae for their survival and growth. Without these algae, many coral reefs would not exist. During periods of elevated seawater temperature, most reef corals lose their algae, which is visible as a dramatic whitening of the reefs, a coral disease known as bleaching.

Most reef corals generally do not occur over 40 m depth, a twilight zone where sunlight is not bright anymore, but some species of the genus Leptoseris are exceptional and may even occur much deeper. At greater depths, seawater is generally colder and corals here may be less susceptible to bleaching than those at shallower depths. Despite the lack of zooxanthellae and its small size, the skeleton structures of the new species indicate that it is closely related to these Leptoseris corals, although it has not been found deeper than 35 m so far.

The species is named Leptoseris troglodyta. The word troglodyta is derived from ancient Greek and means “one who dwells in holes”, a cave dweller. The discovery sheds new light on the relation of reef corals with symbiotic algae. The new species has adapted to a life without them. Consequently, it may not grow fast, which would be convenient because space is limited on cave ceilings. The species description is published in the open access journal ZooKeys.

See also here.

NEW YORK (October 11, 2012)— A new study by the Wildlife Conservation Society and James Cook University says that coral reefs in Aceh, Indonesia are benefiting from a decidedly low-tech, traditional management system that dates back to the 17th century: here.

Scientists from Hebrew University and Technion discover why soft corals have unique pulsating motion: here.

Unique Norwegian protozoan discovery


This video says about itself:

The microscopic life in an Italian lake (Lago di Candia).

Algae and Protozoa are a vital part of the aquatic ecosystem, providing food and shelter for other organisms. As a major part of the world’s biodiversity, they contain a vast array of different biochemistries, morphologies and life cycles. What is more, they are often spectacularly beautiful under the microscope.

From the University of Oslo in Norway:

Mankind’s remotest relative found in Norway

26 April 2012 Oslo, University of

Mankind’s remotest relative is a very rare micro-organism from south-Norway. The discovery may provide an insight into what life looked like on earth almost one thousand million years ago.

Biologists all over the world have been eagerly awaiting the results of the genetic analysis of one of the world’s smallest known species, hereafter called the protozoan, from a little lake 30 kilometer south of Oslo in Norway.

When researchers from the University of Oslo, Norway compared its genes with all other known species in the world, they saw that the protozoan did not fit on any of the main branches of the tree of life. The protozoan is not a fungus, alga, parasite, plant or animal.

“We have found an unknown branch of the tree of life that lives in this lake. It is unique! So far we know of no other group of organisms that descend from closer to the roots of the tree of life than this species. It can be used as a telescope into the primordial micro-cosmos,” says an enthusiastic associate professor, Kamran Shalchian-Tabrizi, head of the Microbial Evolution Research Group (MERG) at the University of Oslo.

His research group studies tiny organisms hoping to find answers to large, biological questions within ecology and evolutionary biology, and works across such different fields as biology, genetics, bioinformatics, molecular biology and statistics.

World’s oldest creature.

Life on Earth can be divided up into two main groups of species, prokaryotes and eukaryotes. The prokaryote species, such as bacteria, are the simplest form of living organisms on Earth. They have no membrane inside their cell and therefore no real cell nucleus. Eukaryote species, such as animals and mankind, plants, fungi and algae, on the other hand do.

The family tree of the protozoan from Ås starts at the root of the eukaryote species.

“The micro-organism is among the oldest, currently living eukaryote organisms we know of. It evolved around one billion years ago, plus or minus a few hundred million years. It gives us a better understanding of what early life on Earth looked like.”, Kamran says to the research magazine Apollon.

How they move.

The tree of life can be divided into organisms with one or two flagella. Flagella are important when it comes to a cell’s ability to move. Just like all other mammals, human sperm cells have only one flagellum. Therefore, mankind belongs to the same single flagellum group as fungi and amoebae.

On the other hand it is believed that our distant relatives from the family branches of plants, algae and excavates (single-celled parasites) originally had two flagella.

The protozoan from Ås has four flagella. The family it belongs to is somewhere between excavates, the oldest group with two flagella, and some amoebae, which is the oldest group with only one flagellum.

“Were we to reconstruct the oldest, eukaryote cell in the world, we believe it would resemble our species. To calculate how much our species has changed since primordial times, we have to compare its genes with its nearest relatives, amoebae and excavates,” says Shalchian-Tabrizi.

Caught with a tasty morsel.

The protozoan is not easy to spot. It lives down in the sludge at the bottom of a lake.

It is 30 to 50 micrometres long and can only be seen with a microscope. When Professor Dag Klaveness of MERG wants to catch the protozoan he sticks a pipe down into the lakebed, removes a column of sludge and pours a bile green algae mixture over it.

The algae are such tempting morsels for the small protozoa that they swim up.

“We can then pick them out, one by one, with a pipette,” says Klaveness.

There are not many of them. And the University of Oslo biologists have not found them anywhere else other than in this lake-

“We are surprised. Enormous quantities of environmental samples are taken all over the world. We have searched for the species in every existing DNA database, but have only found a partial match with a gene sequence in Tibet. So it is conceivable that only a few other species exist in this family branch of the tree of life, which has survived all the many hundreds of millions of years since the eukaryote species appeared on Earth for the first time.”

Not very sociable.

The protozoan lives off algae, but the researchers still do not know what eats the protozoan. Nor do they know anything about its life cycle. But one thing is certain:

“They are not sociable creatures. They flourish best alone. Once they have eaten the food, cannibalism is the order of the day,” notes Klaveness.

The protozoan has a special cell indentation. It looks like a groove.

“The species has the same intracellular structure as excavates. And it uses the same protuberances as amoebae to catch its food. This means that the species combines two characteristics from each family branch of the main eukaryote groups. This further supports the hypothesis that the species from this lake belongs to a primordial group. Perhaps it descended from the antecedents of both the excavates and amoeba?” asks Shalchian-Tabrizi.

The protozoan was discovered as early as 1865, but it is only now that, thanks to very advanced genetic analyses, researchers understand how important the species is to the history of life on Earth.

Breeding enormous quantities of the protozoan.

Dag Klaveness has, together with research fellow Jon Bråte, managed to breed large quantities of the species. No one has done this before. Klaveness has spent the last 40 years specialising in breeding organisms that are difficult to breed or that are difficult to isolate from other species.

Breeding is important if we want to analyse the creature’s genes. More than just a few are needed for a genetic test. Researchers have needed to breed large quantities. The work is demanding and has taken many months.

The protozoan’s favourite food is green algae, but since both the protozoan and the green algae are eukaryote species, i.e. species with real cell nuclei, it is easy to confuse the genes of the protozoan with those of its food in the gene sequencing. Therefore, Klaveness has chosen to feed the protozoan with blue green bacteria, which are genetically very different to the protozoan. Blue green bacteria are not exactly its favourite dish, but the protozoan can only choose between eating or dying.

Blue green bacteria are prokaryotes, i.e. species without membranes or real cell nuclei. This allows the researchers to differentiate between the genes of the protozoan and its food in the gene sequencing.

Klaveness has a number of vats of the protozoan in the laboratory. The algae mixture sinks to the bottom. The protozoan dives down when it wants to eat.

In optimum conditions they divide every second day. However, with blue green bacteria on the menu, which is just as boring as if you only got carrots for several months and nothing else, the protozoan grows much more slowly.

When the protozoa have reproduced enough, they are centrifuged out and gene sequenced. The genes are then compared with equivalent gene sequences from other species. “We have gene sequenced 300,000 parts of the genome (the total genetic material), but we still do not know how large the genome is. We are currently only looking for the most important parts,” explains Kamran Shalchian-Tabrizi.

Traces from primordial times.

The problem is that DNA sequences change a lot over time. Parts of the DNA may have been wiped away during the passing of the years. Since the protozoan is a very old species, an extra large amount of gene information is required.

“It is often the case with such ancient organisms that features they share in common with other known species have been wiped away from the DNA sequence because of long-term mutations. You can compare it with tarmacing. If you tarmac a road enough times, you will no longer see the cobblestones. Therefore, you have to collect large gene sequences to find common traces from prehistoric times.”

Research fellow Sen Zhao was responsible for the extensive, statistical calculations. In order to calculate the family link they have used information from the research group’s own Bioportal in cooperation with the high performance computing group at the University of Oslo.

Resolving evolutionary mysteries.

Kamran Shalchian-Tabrizi explains that the tree of life can provide fundamental answers to great evolutionary mysteries.

“In order to understand what a species is today, we have to understand how they have changed genetically. The tree of life allows us to explain cellular change processes by connecting the genome and morphology (appearance) with its way of life.”

Among other things, Shalchian-Tabrizi wants to use the protozoan to investigate when photosynthesis arose among eukaryote organisms. Photosynthesis takes place in chloroplast.

Chloroplasts were originally free-living, blue green bacteria. If the researchers find genetic residues of these bacteria in the protozoan from Ås, this may indicate that photosynthesis arose earlier than supposed.

“There are many likely scenarios, but we still do not know the answer,” acknowledges Shalchian-Tabrizi.

The researchers also want to question when other characteristics arose, e.g. mitochondria, which are the energy motors of our cells.

Purifying drinking water in Japan.

In recent years researchers have found some apparently matching examples of the protozoan from Ås in Japan and South East Asia. A researcher from Japan arrived in Oslo with a glass of the species solely so that Klaveness could breed them.

“We are now going to gene sequence these organisms, because it is not certain that the genes are the same, even if the morphology is similar,” says Klaveness.

The Japanese hope that the protozoan can be used to purify drinking water by removing toxic, blue green bacteria.

http://www.apollon.uio.no/english/articles/2012/microorganism.html

One-celled life possessed tools for going multicellular. Amoeba uses some of same molecular machinery as more complex organisms. By Laurel Hamers, 12:00pm, October 13, 2016: here.

See also here.

Plant, new for the Netherlands, discovered


This video is about Kampina nature reserve.

Translated from Natuurmonumenten in the Netherlands:

Natuurmonumenten discovers new species

Posted on September 15, 2010

The Netherlands has a new plant species. It is a rare throughout Europe. It is the charales algae species Nitella confervacea which was discovered in the shallow waters of the Winkelsven lake in the Kampina nature reserve in Noord-Brabant province.

Inconspicuous plant

The inconspicuous little plant is about 5 cm and does not have a Dutch name. This particular finding is yet another success story of the big Winkelsven restoration project which started in 2007. …

Meanwhile there are 20 so-called Red List species, including shoreweed and bog pimpernel. On that list are species seriously threatened in our country.

20 million pollution-fighting fish released in Chinese lake


This video from the USA says about itself:

Wild Jumping Carp On Illinois River

Asian Silver Carp have infested the Illinois River. The fish are migrating up the Mississippi River and can’t be stopped.

From British daily The Independent:

China to release 20 million pollution-fighting fish in lake

Saturday, 27 February 2010

Authorities in eastern China have said they will release 20 million algae-eating fish into one of the nation’s most scenic lakes that has been ravaged by pollution.

Taihu Lake, which straddles Zhejiang and Jiangsu provinces, has been severely polluted by sewage as well as industrial and agricultural waste, triggering a blue-green algae plague.

Authorities started using fish to try to clean up the lake in February last year when they released 10 million mostly green and silver carp into the water, after the algae tainted the drinking supply of millions of residents.

Over the next few days, around 20 million more algae-eating fish will be released into the water, the Taihu Lake Fisheries Management Committee said in a statement Monday.

The campaign, funded by the government and public donations, cost a total of 8.6 million yuan (1.3 million dollars), according to the statement.

A silver carp can consume 50 kilogrammes (110 pounds) of algae and other plankton in its lifetime while gaining only one kilogramme in weight, authorities have said.

Millions of algae-eating fish have been used in the past to clean up Taihu and other lakes, with previous efforts hailed as a boon for the local fishing industry despite concerns over consumption of fish that have feasted on toxins.

Algae blooms, which are common on freshwater lakes in China, are chiefly caused by the presence of untreated sewage containing high concentrations of nitrogen, a main ingredient in detergents and fertilisers.

China’s environment has suffered severely amid the nation’s breakneck economic growth over the past three decades.

See also here.

How algae ‘enslavement’ threatens freshwater bodies: How toxic, blue-green algae out-compete other organisms: here.

‘Dancing’ algae discovered


From New Scientist:

‘Dancing’ algae can waltz and minuet

* 17:35 20 April 2009 by Michael Marshall and Sandrine Ceurstemont

Freshwater algae can dance around each other in stable groups, held together only by fluid flows in the surrounding water.

Raymond Goldstein of the University of Cambridge and colleagues studied a well-known alga called Volvox. This species lives in colonies of cells around a thousand strong: the individual cells live on the surfaces of spheres of jelly.

Each cell has a pair of flagella: thin flexible rods that extend out into the surrounding water and function as outboard motors, propelling the colonies around – as well as causing them to spin like tops.

When the colonies swim near the surface of the water, they can get together in one of two formations.

The first is called the “waltz”: the two colonies orbit around each other, like a planet circling the sun. The second is the “minuet”, in which the colonies oscillate back and forth, as if held together by an elastic band.

Goldstein’s team have developed a mathematical analysis that explains the two dances – they are caused by the unusual behaviour of the water near its surface.

Journal reference: Physical Review Letters, in press (pdf)

These videos are about human waltzing and minuet.

Coralline Algae In The Mediterranean Lost Their Tropical Element Between 5 And 7 Million Years Ago: here.

Vampire Algae Suck on Salad: here.

Vanishing Marine Algae Can Be Monitored From a Boat With Your Smartphone: here.

Spring Rain, Then Foul Algae in Ailing Lake Erie: here.

New algae and sea anemone species discovered in Aleutians


This video is called Killer Sea Anemone attacks poor crab.

From the University of Alaska Fairbanks:

Divers find new species in Aleutians

Fairbanks, ALASKA– There are unknown creatures lurking under the windswept islands of the Aleutians, according to a team of scientific divers from the University of Alaska Fairbanks.

This summer, while completing the second phase of a two-year broad scientific survey of the waters around the Aleutian Islands, scientists have discovered what may be three new marine organisms. This year’s dives surveyed the western region of the Aleutians, from Attu to Amila Island, while last year’s assessment covered the eastern region.

During the dives, two potentially new species of sea anemones have been discovered. Stephen Jewett, a professor of marine biology and the dive leader on the expedition, says that these are “walking” or “swimming” anemones because they move across the seafloor as they feed. While most sea anemones are anchored to the seabed, a “swimming” anemone can detach and drift with ocean currents. The size of these anemones ranges from the size of a softball to the size of a basketball.

Another new species is a kelp or brown algae that scientists have named the “Golden V Kelp” or Aureophycus aleuticus. According to Mandy Lindeberg, an algae expert with NOAA’s National Marine Fisheries Service and a member of the expedition, the kelp may represent a new genus, or even family, of the seaweed. Up to ten feet long, the kelp was discovered near thermal vents in the region of the Islands of the Four Mountains.

“Since the underwater world of the Aleutian Islands has been studied so little, new species are being discovered, even today,” said Jewett. He adds that even more new species may be revealed as samples collected during the dives continue to be analyzed.

From Deep Sea News:

An enormous sea anemone from 2500m depth on the East Pacific Rise was reported in the journal Marine Biology. The monstrous actiniarian Boloceroides daphneae is abundant on boulders, cliffs, and rocky outcrops near hydrothermal vent sites but not on them, writes author Marymegan Daly from Ohio State University. The largest living specimen she found had a column diameter of 1m, a tentacle crown of 2m diameter, and tentacles trailing an estimated 3m and more. That’s just downright dangerous. B. daphneae’s closest living relative is the comparatively diminutive Cerianthid anemone found in warmer coastal waters.

The new species has been known since 1990, but it was tough to collect, and it provides a good example of commonly encountered but largely unstudied species in the deep sea environment.

The middle of the South Pacific is as far away from land as you can possibly get. Solar irradiance is dangerously high, reaching a UV-index that is labelled ‘extreme’. There are no dust particles or inflows from the land and as a result these waters have extremely low nutrient concentrations, and thus are termed ‘ultraoligotrophic’. Chlorophyll-containing phytoplankton (minute algae) are found only at depths greater than a hundred meters, making surface South Pacific waters the clearest in the world. Due to its remoteness and enormous size — the South Pacific Gyre covers 37 million km2 (for comparison, the US cover less than 10 million km2) -, it is also one of the least studied regions on our planet: here.

New algae discovered in Arctic ocean


Arctic oceanFrom Biology News Net:

An international team of scientists including Université Laval biologist Connie Lovejoy has discovered new life forms in the Arctic Ocean.

The team’s findings are reported in the January 12 edition of the journal Science.

The researchers have discovered a new group of microscopic organisms, which they have baptized “picobiliphytes”: pico because of their extremely small size, measured in millionths of a meter, bili because they contain biliproteins, highly fluorescent substances that transform light into biomass, and phyte meaning they are plants.

The discovery came from carefully analyzing DNA sequences belonging to vast communities of micro-organisms living in the ocean.

“There was one group of sequences that just didn’t line up with any of the known groups,” explains Dr. Lovejoy.

“In fact, the divergence of this group from known organisms is as great as the difference between land plants and animals,” adds the scientist.

Over this last year the team has been scouring data bases, verifying their results and applying new techniques to their samples.

They can now confirm that these new life forms are abundantly distributed throughout northern seas.

They have yet to be brought into culture, but can be seen using advanced microscopy techniques.

See also here.

It is to be hoped that global warming will not wipe out these small newly discovered life forms, as it also threatens bigger Arctic life forms, like polar bears (see also here).

Well … ExxonMobil and George W Bush deny that there is global warming [sarcasm off] …

Wildlife of Baffin island and high Arctic: here.