Newcastle Researchers Leapfrog Ahead in World-First
University of Newcastle researchers have successfully developed a method to freeze frog embryonic cells in a world-first breakthrough that could slow the threat of extinction to hundreds of frog species.
The researchers have separated, isolated and frozen the embryonic cells of an Australian Ground Frog (the Striped Marsh Frog, Limnodynastes peronii), using cryopreservation techniques that will now allow for cloning.
This is the first time anyone in the world has successfully used slow-freezing techniques on amphibian cells, project leader at the University of Newcastle, Professor Michael Mahony, said.
“Almost 200 frog species have been lost in the past 30 years due to disease and a further 200 species face imminent threat – this is the worst rate of extinction of any vertebrate group,” he said.
“Amphibian eggs and early embryos, unlike human eggs and embryos, are large in size and have traditionally presented a challenge to researchers attempting to cryo-preserve and store frog genomes, as they would shatter during the freezing process.
“The new technique, developed by our University of Newcastle researchers, will act as an insurance policy to buy us time for species on the edge of extinction, as we search for answers to diseases and other threats.”
Professor Mahony said the development would have wider implications for other species facing extinction.
“Not only will it help us preserve the genetic diversity of frogs, but this discovery could also help in the conservation of other species with large embryonic cells, such as fish.”
The University of Newcastle is leading the world on research into amphibian protection. This latest discovery follows on from recent work with other universities on the Lazarus project, which generated live embryos using cells from an extinct Australian frog.
The technical work was led by Dr John Clulow and Professor Michael Mahony, alongside Ms Bianca Lawson and Mr Simon Clulow.
Photograph courtesy of the Journal of Comparative Psychology.
Researchers Document Sea Lion’s Synchronized Head Bobbing to ‘Boogie Wonderland’
Newswise — WASHINGTON – Move over dancing bears, Ronan the sea lion really does know how to boogie to the beat.
Video Credit: Pinniped Lab
A California sea lion who bobs her head in time with music has given scientists the first empirical evidence of an animal that is not capable of vocal mimicry but can keep the beat, according to new research published by the American Psychological Association.
The study’s authors suggest that their findings challenge current scientific theories that an animal’s ability to synchronize its movements with sound are associated with the same brain mechanisms that allow for vocal mimicry in humans and some birds such as cockatoos, parrots, and budgerigars. The findings were published online April 1 in APA’s Journal of Comparative Psychology.
“Understanding the cognitive capabilities of animals requires carefully controlled, well-designed experiments,” said study co-author Colleen Reichmuth, PhD, with the Institute of Marine Sciences at the University of California at Santa Cruz. “This study is particularly rigorous because it examines, step-by-step, the learning conditions that supported the emergence of this complex behavior.”
Ronan, a 3-year-old sea lion, demonstrated her ability to bob to the beat in six experiments led by doctoral candidate Peter Cook at the Long Marine Lab at UCSC.
“Dancing is universal among humans, and until recently, it was thought to be unique to humans as well,” said Cook. “When some species of birds were found to have a similar capability for rhythmic movement, it was linked to their ability to mimic sound. Now we’re seeing that even mammals with limited vocal ability can move in time with a beat over a broad range of sounds and tempos.”
Ronan’s first musical “dance” lesson was to the tune of a simplified section of John Fogerty’s “Down on the Corner,” the study said. Once Ronan was trained to bob her head to music, the researchers tested her with two pop songs, “Everybody” by the Backstreet Boys, and “Boogie Wonderland” by Earth, Wind and Fire. Without any prior exposure to the songs, Ronan was able to bob to the beat of both songs over the course of multiple trials, according to the study. She then showed that she could follow along to five different tempos of “Boogie Wonderland.”
Ronan’s bobbing skills markedly improved over the course of the trials and apparently endured, the study found. The researchers gave her a follow-up test a few weeks after the final session and she was successful in keeping the beat with each of the sounds previously used, maintaining a minimum of 60 consecutive bobs to each of the various beats.
At the beginning of the experiments, Ronan was first trained to move in time to a hand signal, which was replaced by a simple non-musical sound signal. When she successfully completed tests by bobbing her head to various rhythmic sounds, she was rewarded with a fish, the study said.
The researchers varied the types and speed of the sounds to verify that she was actually following the rhythm by bobbing her head. To rule out that she wasn’t simply bobbing her head in response to the previous beat, they tested her using two computer-generated, metronome-like ticks – one that did not miss a beat and the other that did. Ronan kept the beat going even when the metronome missed a beat, according to the study.
Most kindergarteners can tell you that an animal eats with its mouth, not its butt. One species of sea cucumber, however, didn’t appear to get the memo: Scientists have discovered that the giant California sea cucumber (Parastichopus californicus) actually uses its anus as a second mouth. Scientists already knew that the marine invertebrate, which lives in the shallow ocean waters off the Pacific coast of North America, breathes with its butt. Because they don’t have lungs, sea cucumbers rely on respiratory trees, a set of long tubes running down either side of the body with a lot of different branches. P. californicus is shaped like a hollow tube, with a mouth at one end and its anus at the other.
Two weeks ago, a group of sailors off the coast of New Zealand leaned over the side of their boat, dropped a contraption into the Pacific Ocean and watched it disappear. Using an app they’d downloaded to a smartphone, they logged a reading from the underwater device, along with their GPS location and the water temperature. In just a few minutes’ time, they had become the first participants in a new program launched by the UK’s Plymouth University Marine Institute which allows citizen scientists to help climatologists study the effects of climate change on the oceans.
Researchers writing in the Proceedings of the Royal Society A say they have developed a new robotic fish that has lateral line sensing capabilities.
The FILOSE team members have spent four years investigating fish lateral line sensing, which is a sensing organ found in aquatic vertebrates used to detect movement and vibration in the surrounding water. This organ essentially helps a fish’s orientation in the water. The team set out to understanding how a fish detects and exploits flow features in water, and then use their findings to develop efficient underwater robots based on biological principles.
Flow can be measured and characterized on many salient features that do not change. This “flowscape” is a flow landscape that helps fish and robots orient themselves, navigate, and control their movements in water.
Photo: Prof. Maarja Kruusmaa and FILOSE fish robot. Credit: Jelena Pijonkina
Citizen science surveys compare well with traditional scientific methods when it comes to monitoring species biodiversity – according to new research from the University of East Anglia.
Research published today in the journal Methods in Ecology and Evolution shows that methods to record marine diversity used by amateurs returned results consistent with techniques favoured by peer-reviewed science.
The findings give weight to the growing phenomenon of citizen science, which sees data crowd-sourced from an army of avid twitchers, divers, walkers and other wildlife enthusiasts.
The field study compared methods used by ‘citizen’ SCUBA divers with those used by professional scientists, to measure the variety of fish species in three Caribbean sites.
The divers surveyed the sites using two methods – the ‘belt transect’, used in peer reviewed fish diversity studies, and the ‘roving diver technique’, used by the Reef Environmental Education Foundation (REEF) volunteer fish survey project.
Two teams of 12 divers made 144 separate underwater surveys across the sites over four weeks.
While the traditional scientific survey revealed sightings of 106 different types of fish, the volunteer technique detected greater marine diversity with a total of 137 in the same waters.
Dr Ben Holt, from UEA’s school of Biological Sciences, led the research in partnership with the Centre for Marine Resource Studies in the Caribbean and the University of Copenhagen, Denmark.
He said: “The results of this study are important for the future of citizen science and the use of data collected by these programs. Allowing volunteers to use flexible and less standardised methods has important consequences for the long term success of citizen science programs. Amateur enthusiasts typically do not have the resources or training to use professional methodology. Our study demonstrates the quality of data collected using a volunteer method can match, and in some respects exceed, protocols used by professional scientists.
“Enlisting the help of a large pool of volunteers helps professional researchers collect valuable data across many ecosystems.
“The popularity of SCUBA diving has resulted in monitoring of the underwater environment on a scale that was previously impossible. For example, the REEF method has been used by volunteers in more than 160,000 underwater surveys across the world. It would have cost many millions of pounds for professionals to have undertaken the same work.
“Very few, if any, scientific groups can collect data on the scale that volunteer groups can, so our proof that both methods return consistent results is very encouraging for citizen science in general.
“I think we will really see the value of volunteer schemes increase in future. We’re living in a world that’s changing very significantly. Environmental changes are having a big impact on ecosystems around us so we need to harness new ways of measuring the effect.
“For example Lion fish is an invasive species which was not in the Caribbean until roughly 10 years ago. They have now become a real problem in many areas and this invasion has been tracked using volunteer data. Following our study, scientists can have more confidence when using these data to consider the impact of threats, such as invasive species, on the wider natural communities.
“It is important to note that our study does not consider the abilities of the individuals performing the surveys and this is also an important consideration for any large scale biodiversity program. By addressing these issues we can make important steps towards enabling the large pool of volunteer enthusiasts to help professional researchers by collecting valuable data across many ecosystems.”
The research was carried out in under water sites close to South Caicos in the Turks and Caicos Islands.
Mysterious glow of light found to correlate with coral stress prior to bleaching
Coral reefs not only provide the world with rich, productive ecosystems and photogenic undersea settings, they also contribute an economic boost valued at hundreds of billions of dollars. But their decline in recent years due to a variety of threats—from pollution to climate warming—has lent urgency to the search for new ways to evaluate their health.
A new study by Scripps Institution of Oceanography at UC San Diego scientists has revealed that fluorescence, the dazzling but poorly understood light produced by corals, can be an effective tool for gauging their health.
As described in the March 12 edition of Scientific Reports (a publication of the Nature Publishing Group), marine biologists Melissa Roth and Dimitri Deheyn describe groundbreaking research using fluorescence to test coral stress prompted from cold and heat exposures.
In experimental studies conducted at Scripps, Roth and Deheyn tested the common Indo-Pacific reef-building branching coral Acropora yongei under various temperatures. Branching corals are susceptible to temperature stress and often one of the first to show signs of distress on a reef. Roth and Deheyn found, at the induction of both cold and heat stress, corals rapidly display a decline in fluorescence levels. If the corals are able to adapt to the new conditions, such as to the cold settings in the experiment, then the fluorescence returns to normal levels upon acclimation.
While the corals recovered from cold stress, the heat-treated corals eventually bleached and remained so until the conclusion of the experiment. Coral bleaching, the loss of tiny symbiotic algae that are critical for coral survival, is a primary threat to coral reefs and has been increasing in severity and scale due to climate change. In this study, the very onset of bleaching caused fluorescence to spike to levels that remained high until the end of the experiment. The researchers noted that the initial spike was caused by the loss of “shading” from the symbiotic algae.
“This is the first study to quantify fluorescence before, during, and after stress,” said Deheyn. “Through these results we have demonstrated that changes in coral fluorescence can be a good proxy for coral health.”
Deheyn said the new method improves upon current technologies for testing coral health, which include conducting molecular analyses in which coral must be collected from their habitat, as opposed to fluorescence that can be tested non-invasively directly in the field.
Corals are known to produce fluorescence through green fluorescent proteins, but little is known about the emitted light’s function or purpose. Scientists believe fluorescence could offer protection from damaging sunlight or be used as a biochemical defense generated during times of stress.
“This study is novel because it follows the dynamics of both fluorescent protein levels and coral fluorescence during temperature stress, and shows how coral fluorescence can be utilized as an early indicator of coral stress” said Roth, a Scripps alumna who is now a postdoctoral scientist at Lawrence Berkeley National Laboratory and UC Berkeley.
Alburnoides manyasensis. Photograph courtesy of Davut Turan; CC-BY 3.0
The newly described species Alburnoides manyasensis, belongs the large carp family Cyprinidae that includes freshwater fishes such as he carps, the minnows, and their relatives. This is the largest fish family, and more notably the largest family of vertebrate animals, with the remarkable numbers of over 2,400 species. Cyprinids are highly important food fish because they make the largest part of biomass in most water types except for fast-flowing rivers.
The genus Alburnoides is widely distributed in Turkey in rivers and streams of basins of the Marmara, Black and Aegean seas, being absent only from the Mediterranean Sea basin. It is distinguished by small black spots located on each side of the fish, especially prominent on the anterior of the body. The description was published in the open access journal Zookeys.
Alburnoides manyasensisis is described from the Koca Stream drainage of Lake Manyas, Marmara Sea basin in Anatolia and is currently only associated with this specific locality. The name of the species is an adjective that is derived from the name of Lake Manyas to which the new species is possibly endemic. The new species inhabits clear fast running water with cobble and pebble substrates. It is a comparatively small representative of the family with maximum known body length of only 92 cm while the largest representative of the family, the giant barb (Catlocarpio siamensis) can reach up to the astonishing 3 m in length.
Setting up home in the stinging tentacles of a sea anemone might seem like a risky option, but anemonefish – popularly known as clownfish – are perfectly content in their unlikely abode. Fending off peckish anemone predators in return for refuge, plucky clownfish have achieved a satisfactory arrangement with their deadly partners. Yet Joe Szczebak from Auburn University, USA, wondered whether there might be more to the unconventional collaboration than met the eye. According to Szczeback, coral reefs are awash with oxygen during the day, but levels can plummet overnight when photosynthesis has ceased. Adding that some damselfish waft oxygen-rich water over corals at night to supplement their oxygen supply, Szczebak wondered whether clownfish might have struck a similar deal with their anemone hosts. ‘There had been almost no research done on the clownfish–anemone mutualism at night’, explains Szczebak, so he and his Master’s thesis advisor, Nanette Chadwick, decided to find out whether clownfish fan their anemone hosts to supplement their meagre nocturnal oxygen supply (p. 970).
Szczebak and Chadwick travelled to Fuad Al-Horani’s physiology lab at the Marine Science Station in Aqaba, Jordan, and went SCUBA diving in the Red Sea to find the diminutive fish and their anemone partners. Then the team isolated each fish from its anemone and measured their individual oxygen consumption rates before reuniting the partners. They discovered that the fish and anemone consumed 1.4 times more oxygen when they were together than when they were apart. Something was happening when the fish and its anemone were together to increase their oxygen consumption, but Szczebak wasn’t sure what.
Having successfully returned the fish to their Red Sea home before flying back to the United States, Szczebak repeated the experiments with Ray Henry’s help in Chadwick’s Auburn lab. However, this time he tried an additional test. Separating the clownfish from its anemone with plastic mesh – so that the clownfish could still see its partner and they could smell each other – Szczebak remeasured their oxygen consumption, but it was still lower than when they were in contact. ‘There was something about the physical contact between them that was the source of the increase’, says Szczebak.
Spending long nights filming the clownfish as they nestled in amongst their anemone’s tentacles, Szczebak realised that the fish were much more active than had been thought previously. He frequently saw the fish fanning the anemone with their rapidly weaving fins and the fish often burrowed deep into their host, sometimes making a 180 deg turn deep within the mass of tentacles to open up the collapsed anemone and apparently circulate water through it. However, when Szczebak measured the oxygen consumption of isolated anemones as he flowed water through them at speeds ranging from 0.5 to 8.0 cm s−1, their oxygen consumption never increased by as much as it did when paired with a clownfish, suggesting that the clownfish also contribute the partnership’s increased oxygen consumption.
‘I think that I have found foundational evidence that, like similar symbioses on coral reefs, anemonefish may actively modulate flow conditions surrounding their host to benefit them under low oxygen scenarios’, says Szczebak. He adds that Chadwick’s group is continuing to investigate whether the fish indulge in their nocturnal antics purely to supplement the anemone’s oxygen supply or for an as-yet-undetermined reason with the additional benefit of improved circulation.
Szczebak, J. T.,
Henry, R. P.,
Al-Horani, F. A. and
Chadwick, N. E.
(2013). Anemonefish oxygenate their anemone hosts at night. J. Exp. Biol.216, 970-976.
Using underwater video cameras to record fish feeding on South Pacific coral reefs, scientists have found that herbivorous fish can be picky eaters – a trait that could spell trouble for endangered reef systems.
In a study done at the Fiji Islands, the researchers learned that just four species of herbivorous fish were primarily responsible for removing common and potentially harmful seaweeds on reefs – and that each type of seaweed is eaten by a different fish species. The research demonstrates that particular species, and certain mixes of species, are potentially critical to the health of reef systems.
Related research also showed that even small marine protected areas – locations where fishing is forbidden – can encourage reef recovery.
“Of the nearly 30 species of bigger herbivores on the reef, there were four that were doing almost all of the feeding on the seven species of seaweeds that we studied,” said Mark Hay, a professor in the School of Biology at the Georgia Institute of Technology. “We did not see much overlap in the types of seaweed that each herbivore ate. Therefore, if any one of these four species was removed, that would potentially allow some macroalgae to proliferate.”
The research has been published online ahead of print by the journal Ecology and will be included in a future print edition. The study was supported by the National Science Foundation (NSF), the National Institutes of Health (NIH) and the Teasley Endowment to Georgia Tech.
Macroalgae – known as seaweeds – pose a major threat to endangered coral reefs. Some seaweeds emit chemicals that are toxic to corals, while others smother or abrade corals. If seaweed growth is not kept in check by herbivorous fish, the reefs can experience rapid decline. Overfishing of coral reef ecosystems has decimated fish populations in many areas, contributing to overgrowth by seaweed, along with the loss of corals and their ability to recover from disturbance.
To determine which fish were most important – information potentially useful for protecting them – Hay and Georgia Tech graduate student Douglas Rasher moved samples of seven species of seaweed into healthy reef systems that had large populations of fish.
They set up three video cameras to watch the reef areas, then left the area to allow the fish to feed. They repeated the experiment over a period of five days in three different marine protected areas located off the Fiji Islands. In all, Rasher watched more than 45 hours of video to carefully record which species of fish ate which species of seaweed.
“The patterns were remarkably consistent among the reefs in terms of which fish were responsible for removing the seaweed,” said Rasher. “Because different seaweeds use different defense strategies to deter herbivores from eating them, a particular mix of fish – each adapted to a particular type of seaweed – is needed to keep seaweeds off the reef.”
Among the most important were two species of unicornfish, which removed numerous types of brown algae. A species of parrotfish consumed red seaweeds, while a rabbitfish ate a type of green seaweed that is particularly toxic to coral. Those four fish species were responsible for 97 percent of the bites taken from all the seaweeds.
“It’s not enough to have herbivorous fish on the reef,” said Hay, who holds the Harry and Linda Teasley Chair in Environmental Biology at Georgia Tech. “We need to have the right mix of herbivores.”
While just four fish species consumed the large seaweeds, Rasher observed a different set of species involved in what he termed “maintenance” – the removal of small algal growths before they have a chance to grow.
“Through our videos, we were able to observe both groups in action,” he said. “There was not only little overlap in which fishes ate the large seaweeds, but there was also little overlap between fishes that comprised the two groups.”
To help determine why certain fish ate certain seaweed, the researchers played a trick on the unicornfish. They removed chemicals from each seaweed species that the unicornfish avoided and coated them individually on a species of seaweed that the unicornfish were accustomed to eating. That caused the fish to stop eating the chemical-laced seaweed, suggesting that chemical defenses kept them from consuming some seaweeds.
The researchers also compared the quality of coral reefs in marine protected areas to those in areas where fishing has been allowed. There are an estimated 300 marine protected areas in the Fiji Islands, most governed by local villages that have considerable autonomy over reef management.
Surveying these larger areas, the researchers found strong negative associations between the abundance or diversity of seaweed on the reef and diversity of herbivorous fishes at the sites they studied.
They found that strict rules against fishing in certain protected areas had led to a regeneration of corals, and that the contrast to fished areas nearby – some just 500 meters apart – was dramatic. The protected reefs supported as much as 11 times more live coral cover, 17 times more herbivorous fish biomass and three times more species diversity among herbivorous fishes as the unprotected areas.
“What we noted in Fiji is that where reefs are fished, they look like the devastated reefs in the Caribbean,” said Hay. “There’s a lot of seaweed, there’s almost no coral and there aren’t many fish in these flattened areas. But right next to them, where fishing hasn’t been allowed for the past eight or ten years, the reefs have recovered and have high coral cover, almost no seaweed and lots of fish.”
Although both fished and protected areas had only seven percent coral cover ten years ago, today the protected areas have recovered.
“This really demonstrates the value of reef protection, even on small scales,” Rasher said. “There is a lot of debate about whether or not small reserves work. This seems to be a nice example of an instance where they do.”
Ultimately, the researchers hope to provide information to village leaders that could help them manage their reefs to ensure long-term health – while helping feed the local human population.
“Not fishing is really not an option for people in these communities,” Rasher said. “Giving the village leadership an idea of which species are essential to reef health and what they can do to manage fisheries effectively is something we can do to help them maintain a sustainable reef food system.”
Beyond the researchers already mentioned, the research also included Andrew Hoey from the ARC Centre of Excellence for Coral Reef Studies at James Cook University in Townsville, Australia.
This research was supported by the National Science Foundation (NSF) under grants OCE 0929119 and DGE 0114400, and by the National Institutes of Health (NIH) under grant U01-TW007401. The opinions expressed are those of the authors and do not necessarily represent the official views of the NSF or NIH.