Sealion

It seems that sea lions have once again pulled the wool over the eyes of researchers. We all know it’s a rough world, and no less is true of those poor orphaned sea lion pups. However, decades of painstaking research has proven that the sea lion females shun any sea lion pups which aren’t there own.. Or do they?

A new bit of genetic research of the populations of Californian sea lions, published this past Monday in the online journal PloS ONE, now sheds some new light on the subject, and states that sea lions are not as cold as they are made out to be.

Up to seventeen percent of the females in the California sea lions populations off of Mexico’s coast will actually take on an orphaned pup as one of their own offspring, according to the new research. What is even more amazing, is that the researchers were able to watch the females care for these pups year after year.
“Females are incredibly aggressive toward pups that aren’t theirs. They’ll bare teeth and bark, sometimes grab and toss pups that aren’t their own away,” explains a marine biologist at Arizona State University who made the discovery through an unrelated research effort, Ramona Flatz. “That they adopt at all really surprised us. We didn’t think it happened.”

So, while the chances are not that high that an orphaned pup can find an adoptive mother, the chance still exists, so like people, there are some decent sea lions out there…

Yucatan peninsula

A Mexican skeleton which was ritually laid to rest in a cave that was once devoid of water, lends clues as to first Americans.

The skeleton which was discovered was supposedly laid to rest more than ten thousand years ago. It is one of the oldest such skeletons in the Americas, and was found in an undersea cave along the Yucatan Peninsula in Mexico.

Back when the skeleton was laid to its final resting place, the region was mostly desert, and the skeleton could lend clues which may shed some light on how he first Americans arrived, and just who they were.

Just about eighty miles south of Cancun, the intricate system of caverns of Chan Hol, which means “little hole”, is like a deep valley along the coast of the Caribbean.

German cave divers back in 2006, swam a remarkable 1,800 feet into the dark treacherous underwater tunnels and, quite by accident, happened across the Ice Age human’s remains ad sent notice to the archaeologists located in the surrounding state of Quintana Roo.

Over the past three years scientists under the guidance of the director of the Desert Museum in Saltillo, Mexico, Arturo Gonzalez, have been poking around and documenting the bones in place, so as not to disturb the scene and lose any vital things which might be offered by the surroundings.

It’s really astounding to think of all the ancient marvels which lie in wait for us under the ocean waves, if only we strap on a scuba tank.

A brand new kind of filament barb has been discovered and described which is from India’s southern tip. This new discovery was released in the newest edition of the Journal of Threatened Taxa. This is really quite an astonishing discovery, and it leads one to wonder what other marvels may be hiding themselves away in the depths of the sea, far from the prying hands of us humans.

Puntius Rohani - Picture from report

Authors, TJ Indra, K Rema, and JD Marcus Knight have dubbed the new barb discovered Puntius rohani, after Rohan Pethiyagoda, an accomplished Ichthyologist, for his contributions on both Sri Lankan and Indian fish.

This new filament barb is distinguished by others of its species by the fact that this particular barb has a black club-shaped blotch by the caudal peduncle. It also seems to lack any other colors or patterns other than this blotch, and it also doesn’t have the black bands near the tip of its caudal fin lobes.

The actual report is really quite riveting, and tells a great deal more about the new filament barb, other differences, discovery, and notations.

If you would like to hear more on this subject, you will need to refer to the paper itself: Devi, KR, TJ Indra and JDM Knight (2010) Puntius rohani (Teleostei: Cyprinidae), a new species of barb in the Puntius filamentosus group from the southern Western Ghats of India. Journal of Threatened Taxa 2(9): 1121-1129. Read the papper (pdf)

Old drawing of dragonfish

The conundrum of why a particular group of deep sea fish have a gap between their skull and spinal columns has finally been solved by a crack team of researchers, which include representatives from the Natural History Museum.

It appears that the Barbeled Dragonfish also have a number of bones missing which would normally connect their skulls to their spine, and this has been puzzling researcher for quite some time.

There are a total of 28 genera of these fish, which represent over 270 species, and all of them have this same gap. However, are these missing bones always the cause?

An international group of scientists including Dr. Nalani Schnell, of the University of Tubingen; Dr Ralf Britz, of the Natural History Museum; and Dr. David Johnson, of the smithsonian Institution in Washington DC.

Together they performed the most in depth and comprehensive study for this group.

They stained the fish so that their bones and nerves would show up in different colors, so they could discern them properly.

The researchers discovered that the bones were one missing in 2 of the different genera of barbeled dragonshish, Chauliodus, and Eustomias and in the Leptostomias gladiator as well. The loss of these bones occurred naturally as they evolved.
Dr Britz explains, ‘In stomiids [barbeled dragonfishes are in the Family Stomiidae], vertebrae develop in an unusual fashion from back to front, which facilitated the loss of front vertebrae. They have failed to form in development leaving a gap between the skull and backbone.

However, the gap in the spine of the other barbeled dragonfish is caused by a lengthening of the notochord.

There you have it… Mystery solved.

diatoms, the most common type of photoplankton.

A recent study has revealed that the previously accepted theor of how and phytoplankton appear in the worlds’ oceans is in fact not correct.

The results of the study have overturned over 50 years of common knowledge about the growth of phytoplankton, which is the foundation of almost all life in the ocean as well as many major fisheries. These results also bring to light new concerns that global warming may actually be stunting the growth of phytoplankton, rather than increasing it.

The study was published in the journal Ecology by a professor of botany at the Oregon State University, Michael Behrenfeld, who just happens to be one of the leading experts in the world when it comes to using remote sensors to take a gander at the productivity in the ocean. This study was also backed up by NASA, it’s good to see they still have an interest in what goes on down here, and not just in what goes on in space.

The new study has concluded that the theory developed in 1953, the “critical depth hypothesis”, is not only incomplete, but also inaccurate in explaining summer phytoplankton appearances which have been observed for the last few centuries in the North Atlantic Ocean. These appearances are the foundation of many of the worlds’ fisheries.

The old theory stated that due to increased light in the spring, the phytoplankton bloomed more, however its been discovered that the production actually goes up in the middle of winter, effectively blowing that theory out of the water.

The new theory is that the winter storms churn the water, and make it more difficult for the organisms that eat the phytoplankton to find them, hence the phytoplankton is more abundant in those months.

The sea holds many mysteries for us, one of which was the mating habits of the deep sea squid. This mystery has now been unraveled, as scientists have discovered a male squid with a humongous elongated penis.

The male squid’s penis is almost as long as its entire body, making it one of the oceans’ studliest creatures…

With this discovery, it really comes as no surprise to learn how the male deep-sea squid impregnates females of the species. He simply uses his well hung penis to shoot out blobs of sperm, which then make their way into the female’s body.

This discovery may also shed some light on just exactly why these giant squid mate in the depths of the ocean.

Dr. Alexander Arkhipkin, a deep-water fisheries expert of the Falkland Islands Government Fisheries Department, has explained how he and his team made this momentous discovery, “The mature male squid was caught during a deep-water research cruise on the Patagonian slope. We took the animal from the catch, and it was moribund with arms and tentacles still moving, and chromatophores on the skin contracting and expanding. When the mantle of the squid was opened for maturity assessment, we witnessed an unusual event. The penis of the squid, which had extended only slightly over the mantle margin, suddenly started to erect, and elongated quickly to 67cm total length, almost the same length as the whole animal.”

This sudden arousal of the deep-sea squid specimen really took the scientific team by surprise, however, it did help us solve the age old mystery of just how exactly deep-sea squid procreate.

All cephlapods are hard put to actually “get down to business” as their bodies are comprised of a closed hood-type feature, which forms a cephalopods body and head.

The creatures utilize this hood-type feature to move about in the water, and they need to ventilate to breathe, to top it off, they also hide their sexual organs inside this structure!

Shallow water cephalopods got around this problem by developing an arm to go about the task.

Their penises are short and produce smaller blobs of sperm, and then one of their available appendages is then used to transfer this sperm into receptacles located on the female of the species.

The actual location of these receptacles varies, and is either on their skin, or internal.

However, the deep-water male squid have a much more direct method, which was just injecting the sperm right into the waiting female. This was the giant mystery, as up until now, the general assumption was that these deep-sea squid had penis sizes comparable to other squid.

However, it appears that not all squid are created equal, and unlike their small penis bearing brethren, they have developed a huge cannon for the job of impregnating the females.

The squid uses his impressive member to actually reach inside the female, and inject the sperm directly to where it needs to go, to prevent it from being washed away.

However, how the sperm actually gets to the female’s reproductive organs, is still shrouded in mystery.

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.

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.

Scientists from the U.S. Geological Survey (USGS) have revealed that largemouth bass injected with oestrogen produces less hepcidin than normally. Hepcidin is an important iron-regulating hormone in fish, amphibians and mammals, and researchers also suspect that hepcidin may act as an antimicrobial peptide. In vertebrate animals, antimicrobial peptides are the body’s first line of defence against unwelcome bacteria and some fungi and viruses, so if there’re right, a lowered amount of these compounds is certainly not good news.

“Our research suggests that estrogen-mimicking compounds may make fish more susceptible to disease by blocking production of hepcidin and other immune-related proteins that help protect fish against disease-causing bacteria,” says lead author Dr. Laura Robertson.

You can find more info in the study “Identification of centrarchid hepcidins and evidence that 17β-estradiol disrupts constitutive expression of hepcidin-1 and inducible expression of hepcidin-2 in largemouth bass (Micropterus salmoides)” by Laura Robertson, Luke Iwanowicz and Jamie Marie Marranca in the latest issue of the journal Fish & Shellfish Immunology. It is the first published study demonstrating control of hepcidin by estrogen in any animal.

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.