World´s first animals, Greenland discovery


This 21 July 2020 video is called The Cambrian Explosion and the evolutionary origin of animals with Professor Paul Smith.

From Uppsala University in Sweden:

Half-a-billion year old microfossils may yield new knowledge of animal origins

November 9, 2020

When and how did the first animals appear? Science has long sought an answer. Uppsala University researchers and colleagues in Denmark have now jointly found, in Greenland, embryo-like microfossils up to 570 million years old, revealing that organisms of this type were dispersed throughout the world. The study is published in Communications Biology.

“We believe this discovery of ours improves our scope for understanding the period in Earth’s history when animals first appeared — and is likely to prompt many interesting discussions,” says Sebastian Willman, the study’s first author and a palaeontologist at Uppsala University.

The existence of animals on Earth around 540 million years ago (mya) is well substantiated. This was when the event in evolution known as the “Cambrian Explosion” took place. Fossils from a huge number of creatures from the Cambrian period, many of them shelled, exist. The first animals must have evolved earlier still; but there are divergent views in the research community on whether the extant fossils dating back to the Precambrian Era are genuinely classifiable as animals.

The new finds from the Portfjeld Formation in the north of Greenland may help to enhance understanding of the origin of animals. In rocks that are 570-560 mya, scientists from Uppsala University, the University of Copenhagen and the Geological Survey of Denmark and Greenland have found microfossils of what might be eggs and animal embryos. These are so well preserved that individual cells, and even intracellular structures, can be studied. The organisms concerned lived in the shallow coastal seas around Greenland during the Ediacaran period, 635-541 mya. The immense variability of microfossils has convinced the researchers that the complexity of life in that period must have been greater than has hitherto been known.

Similar finds were uncovered in southern China’s Doushantuo Formation, which is nearly 600 million years old, over three decades ago. Since then, researchers have been discussing what kinds of life form the microfossils represented, and some think they are eggs and embryos from primeval animals. The Greenland fossils are somewhat younger than, but largely identical to, those from China.

The new discovery means that the researchers can also say that these organisms were spread throughout the world. When they were alive, most continents were spaced out south of the Equator. Greenland lay where the expanse of the Southern Ocean (surrounding Antarctica) is now, and China was roughly at the same latitude as present-day Florida.

“The vast bedrock, essentially unexplored to date, of the north of Greenland offers opportunities to understand the evolution of the first multicellular organisms, which in turn developed into the first animals that, in their turn, led to us,” Sebastian Willman says.

Coral discovery in Great Barrier Reef


This 25 October 2020 video says about itself:

Join RV Falkor as we conduct ROV SuBastian’s 401st dive on a newly discovered 500 m tall reef.

This is the ninth dive of the ‘Northern Depths of the Great Barrier Reef’ expedition.

Today we are exploring this 500 m tall ‘detached’ reef, one of seven other detached reefs offshore of Cape York Peninsula, which lie upon a ~500 m deep ledge extending out from below the Great Barrier Reef shelf. The dive will cross the broader base, then climb the steep flanks of the reef to the summit at about 50 m depth – an underwater mountain climb to find out what is living on this newly discovered reef.

From the Schmidt Ocean Institute:

Scientists have discovered a massive detached coral reef in the Great Barrier Reef — the first to be discovered in over 120 years, Schmidt Ocean Institute announced. Measuring more than 500 meters high — taller than the Empire State Building, the Sydney Tower and the Petronas Twin Towers — the reef was discovered by Australian scientists aboard Schmidt Ocean Institute’s research vessel Falkor, currently on a 12-month exploration of the ocean surrounding Australia.

The reef was first found on Oct. 20, as a team of scientists led by Dr. Robin Beaman from James Cook University was conducting underwater mapping of the northern Great Barrier Reef seafloor. The team then conducted a dive on Oct. 25 using Schmidt Ocean Institute’s underwater robot SuBastian to explore the new reef. The dive was live-streamed, with the high-resolution footage viewed for the first time and broadcast on Schmidt Ocean Institute’s website and YouTube channel.

The base of the blade-like reef is 1.5km-wide, then rises 500m to its shallowest depth of only 40m below the sea surface. This newly discovered detached reef adds to the seven other tall detached reefs in the area, mapped since the late 1800s, including the reef at Raine Island — the world’s most important green sea turtle nesting area.

“This unexpected discovery affirms that we continue to find unknown structures and new species in our Ocean,” said Wendy Schmidt, co-founder of Schmidt Ocean Institute. “The state of our knowledge about what’s in the Ocean has long been so limited. Thanks to new technologies that work as our eyes, ears and hands in the deep ocean, we have the capacity to explore like never before. New oceanscapes are opening to us, revealing the ecosystems and diverse life forms that share the planet with us.”

“We are surprised and elated by what we have found,” said Dr. Beaman. “To not only 3D map the reef in detail, but also visually see this discovery with SuBastian is incredible. This has only been made possible by the commitment of Schmidt Ocean Institute to grant ship time to Australia’s scientists.”

The discovery of this new coral reef adds to a year of underwater discoveries by Schmidt Ocean Institute. In April, scientists discovered the longest recorded sea creature — a 45m siphonophore in Ningaloo Canyon, plus up to 30 new species. In August, scientists discovered five undescribed species of black coral and sponges and recorded Australia’s first observation of rare scorpionfish in the Coral Sea and Great Barrier Reef Marine Parks. And the year started with the discovery in February of deep sea coral gardens and graveyards in Bremer Canyon Marine Park.

“To find a new half-a-kilometer tall reef in the offshore Cape York area of the well-recognized Great Barrier Reef shows how mysterious the world is just beyond our coastline,” said Dr. Jyotika Virmani, executive director of Schmidt Ocean Institute. “This powerful combination of mapping data and underwater imagery will be used to understand this new reef and its role within the incredible Great Barrier Reef World Heritage Area.”

The Northern depths of the Great Barrier Reef voyage will continue until Nov. 17 as part of Schmidt Ocean Institute’s broader year-long Australia campaign. The maps created will be available through AusSeabed, a national Australian seabed mapping program, and will also contribute to the Nippon Foundation GEBCO Seabed 2030 Project.

New gall wasp species discovery


Allorhogas gallifolia is a new species of wasp discovered in live oak trees. First collected in 2014 by students in the lab of Rice evolutionary biologist Scott Egan, A. gallifolia is one of four new wasp species described in the study. (Credit: Ernesto Samacá-Sáenz/UNAM)

From Rice University in the USA:

Discovery adds new species a lab’s ghoulish insect menagerie

October 26, 2020

A horrifying insect soap opera with vampires, mummies and infant-eating parasites is playing out on the stems and leaves of live oak trees every day, and evolutionary biologist Scott Egan found the latest character — a new wasp species that may be a parasite of a parasite — within walking distance of his Rice University lab.

Egan, an associate professor of biosciences at Rice, studies gall wasps, tiny insects that cast a biochemical spell on live oaks. When gall wasps lay their eggs on oak leaves or stems, they chemically program the tree to unwittingly produce a tumor-like growth, or gall, which first shelters the egg and then feeds the larval wasp that hatches from it.

Egan describes the wasps as “ecosystem engineers,” because their galls are attractive morsels that harbor a supporting cast of opportunistic ne’er-do-wells, thieves and killers. It’s a great setting to study how competition for resources drives evolution, and Egan and his students have spent more than a decade documenting the eerie, interspecies who’s-eating-who drama.

The latest species they discovered at Rice, Allorhogas gallifolia (al-UHROH’-guhs GAHL’-ihf-ohl-eeuh), is one of four new wasp species from the genus Allorhogas that Egan and collaborators Ernesto Samaca-Saenz and Alejandro Zaldivar-Riveron at the National Autonomous University of Mexico (UNAM) in Mexico City described in a study this month in Insect Systematics and Diversity.

“They lay their egg in another wasp’s gall,” Egan said of A. gallifolia, which his group first hatched in 2014. “They’re using the gall as a resource, and we’re still not certain how, but I think they’re attacking herbivorous caterpillars that are feeding on the gall tissue, and the wasp larva are eating those caterpillars after they hatch.”

He said more than 50 species of Allorhogas have been found in Central America and Mexico, but only two species were previously documented in the United States, one at the University of Maryland campus in 1912 and another some years later in Arizona.

The A. gallifolia found at Rice was collected as part of an effort to describe the community of natural enemies for one species of gall wasp, Belonocnema treatae (behl-uh-NAHK’-nee-muh TREE’-tee). In that study and others like it that Egan’s lab has published for other gall species, thousands of galls are collected across the southeastern United States, and everything that emerges from the galls is studied and cataloged. Egan describes the operation, which runs almost 365 days per year, as a “factory of discovery,” and A. gallifolia was one of many mysterious specimens it has produced.

“It did not match any of the previously described species, so we documented that in our 2016 paper and raised the hypothesis that this might be a new species,” Egan said. “A year or two went by and lead author Ernesto Samaca-Saenz contacted us and offered to collaborate on determining if this lineage was, in fact, a new species.”

Samaca-Saenz is a graduate student in the UNAM lab of Zaldivar-Riveron, an expert in Allorhogas and similar predatory wasps, which can be used by farmers as biological controls for crop pests. By the time Samaca-Saenz reached out about the 2016 paper, Egan’s lab had collected a number of other undescribed specimens that they also suspected were new species of Allorhogas. The email kicked off a close collaboration that has taken Rice researchers on a number of trips to Mexico to conduct field work and science outreach in remote village schools.

While the jury is still out on exactly how A. gallifolia interacts with other species on the galls of B. treatae, Egan said he, Samaca-Saenz and Zaldivar-Riveron have discussed a number of hypotheses.

“They think it could be phytophagous, meaning it’s actually just eating plant material, or that it could be a gallmaker itself,” Egan said. “But I’m convinced that these guys are predators of caterpillars that live inside the Belonocnema galls and eat the gall plant material. I think the larval wasp eats the caterpillar and then emerges out of the side of the gall.”

Egan said it will take more research to determine whether that hypothesis is true. If it is, it would be “a whole new way of life that would be unknown to this entire genus.” But it would not be the first — or the creepiest — interaction between species that Egan and his colleagues have found.

Take 2018’s discovery, for example, that the parasitic vine Cassytha filiformis (kuh-SIHTH’-uh FIHL’-ih-form-ihs), commonly known as the love vine, targets B. treatae galls and sucks so many nutrients out of them that it mummifies the larval wasps inside. That marked the first observation of a parasitic plant attacking a gall-forming wasp, but it could not match the ghoulish weirdness of the crypt-keeper wasp they discovered in 2017.

Euderus set (yoo-DEHR’-uhs SEHT’) is so diabolical that it was named for Set, the Egyptian god who trapped, murdered and dismembered his brother in a crypt. E. set — which Egan discovered on a family vacation in Florida and later found on a tree in his front yard — lays its egg inside the gall of the Bassettia pallida (buh-SEHT’-eeuh PAL’-ih-duh) wasp. Both eggs hatch and the larvae live side by side, maturing inside the gall. When the pair are large enough to emerge as adults, E. set manipulates its step-sibling into trying to escape before its emergence hole is finished. When B. pallida’s head gets stuck in the undersized hole, E. set begins eating. Starting from the tail, it devours a tunnel through its roommate, emerging through the head to take its place in the world outside.

There are more than 1,400 known species of gall-forming wasps, and Egan said he believes there are many more species waiting to be discovered in their plant/bug-eat-bug-eat-plant corner of the world.

“We’ve focused on the gall former Belonocnema a lot, and that’s where we initially found this first Allorhogas,” he said. “When we reared out that entire community and tried to key out each of the members, A. gallifolia was one of those things where we could not narrow it down to a species. Nothing fit the description.

“Twenty-five percent of all the things we reared out of Belonocnema fit that same type of uncertainty,” Egan said. “We can’t find anything that’s ever been described like them before. Some of those, including one I have on my desk right now, are also mostly likely new species. Considering there are 90 oak species in the United States, and I have studied only three of them, this is the tip of the biodiversity iceberg.”

The research was supported by the UNAM Directorate General for Academic Personnel Affairs (IN201119) and the UNAM General Directorate of Computing and Information and Communication Technologies (LANCADUNAM-DGTIC-339).

Elkhorn coral fights for survival


This 2016 video says about itself:

9 Colonies of Elkhorn Coral (Acropora palmata). Study by ARC Reef (Atlantic Reef Conservation) searches for a more viable method of propagating hardy variations of this endangered coral. Increasing survival rates against multiple stressors may help to save this species.

From the University of Miami Rosenstiel School of Marine & Atmospheric Science in the USA:

Elkhorn coral actively fighting off diseases on reef

Findings showed coral has core immune response regardless of disease type

October 23, 2020

As the world enters a next wave of the ongoing COVID-19 pandemic, we are aware now more than ever of the importance of a healthy immune system to protect ourselves from disease. This is not only true for humans but corals too, which are in an ongoing battle to ward off deadly diseases spreading on a reef.

A new study led by researchers at the University of Miami (UM) Rosenstiel School of Marine and Atmospheric Science looked at the immune system of elkhorn coral (Acropora palmata), an important reef-building coral in the Caribbean, to better understand its response to diseases such as white band disease and rapid tissue loss.

In the experiment, healthy corals were grafted to diseased ones. After one week, the corals were analyzed to study the coral’s overall gene expression in response to disease, if they exhibited an immune response, and whether there were different signatures of gene expression for corals that didn’t show signs of disease transmission. The researchers found that A. palmata has a core immune response to disease regardless of the type of disease, indicating that this particular coral species mounts an immune response to disease exposure despite differences in the disease type and virulence.

“Our results show that elkhorn coral is not immunocompromised but instead is actually actively trying to fight off disease,” said Nikki Traylor-Knowles, an assistant professor of marine biology and ecology at the UM Rosenstiel School and senior author of the study. “This gives me hope that the corals are fighting back with their immune system.”

Based upon these findings, the researchers suggest that corals that did not get disease may have tougher epithelia, a protective layer of cells covering external surfaces of their body. And, that the symbiotic dinoflagellate, Symbiodiniaceae, that live inside corals did not have differences in gene expression in response to disease, but over the course of the two-year study did develop differences.

Coral disease is considered one of the major causes of coral mortality and disease outbreaks are expected to increase in frequency and severity due to climate change and other human-made stressors. The Caribbean branching coral Acropora palmata which has already seen an 80 percent decrease on reefs primarily due to disease, which has resulted in them being classified as threatened under the US Endangered Species Act.

“These corals are keystone species for Florida reefs, so understanding that their immune systems are active is an important component that can be useful for protecting reefs,” said Traylor-Knowles.

How diabolical ironclad beetles survive cars


This 21 October 2020 video is called Diabolical Ironclad Beetle: Unlocking the secrets of its super-tough design.

From Purdue University in the USA:

This beetle can survive getting run over by a car; Engineers are figuring out how

October 21, 2020

Getting run over by a car is not a near-death experience for the diabolical ironclad beetle.

How the beetle survives could inspire the development of new materials with the same herculean toughness, engineers show in a paper published Wednesday (Oct. 21) in Nature.

These materials would be stiff but ductile like a paper clip, making machinery such as aircraft gas turbines safer and longer-lasting, the researchers said.

The study, led by engineers at the University of California, Irvine (UCI) and Purdue University, found that the diabolical ironclad beetle’s super-toughness lies in its two armorlike “elytron” that meet at a line, called a suture, running the length of the abdomen.

In flying beetles, the elytra protect wings and facilitate flight. But the diabolical ironclad beetle doesn’t have wings. Instead, the elytra and connective suture help to distribute an applied force more evenly throughout its body.

“The suture kind of acts like a jigsaw puzzle. It connects various exoskeletal blades — puzzle pieces — in the abdomen under the elytra,” said Pablo Zavattieri, Purdue’s Jerry M. and Lynda T. Engelhardt Professor of Civil Engineering.

This jigsaw puzzle comes to the rescue in several different ways depending on the amount of force applied, Zavattieri said.

To uncover these strategies, a team led by UCI professor David Kisailus first tested the limits of the beetle’s exoskeleton and characterized the various structural components involved by looking at CT scans.

Using compressive steel plates, UCI researchers found that the diabolical ironclad beetle can take on an applied force of about 150 newtons — a load of at least 39,000 times its body weight — before the exoskeleton begins to fracture.

That’s more impressive than sounds: A car tire would apply a force of about 100 newtons if running over the beetle on a dirt surface, the researchers estimate. Other terrestrial beetles the team tested couldn’t handle even half the force that a diabolical ironclad can withstand.

Zavattieri’s lab followed up these experiments with extensive computer simulations and 3D-printed models that isolated certain structures to better understand their role in saving the beetle’s life.

All of these studies combined revealed that when under a compressive load such as a car tire, the diabolical ironclad beetle’s jigsaw-like suture offers two lines of defense.

First, the interconnecting blades lock to prevent themselves from pulling out of the suture like puzzle pieces. Second, the suture and blades delaminate, which leads to a more graceful deformation that mitigates catastrophic failure of the exoskeleton. Each strategy dissipates energy to circumvent a fatal impact at the neck, where the beetle’s exoskeleton is most likely to fracture.

Even if a maximum force is applied to the beetle’s exoskeleton, delamination allows the interconnecting blades to pull out from the suture more gently. If the blades were to interlock too much or too little, the sudden release of energy would cause the beetle’s neck to snap.

It’s not yet known if the diabolical ironclad beetle has a way to heal itself after surviving a car “accident.” But knowing about these strategies could already solve fatigue problems in various kinds of machinery.

“An active engineering challenge is joining together different materials without limiting their ability to support loads. The diabolical ironclad beetle has strategies to circumvent these limitations,” said David Restrepo, an assistant professor at the University of Texas at San Antonio who worked on this project as a postdoctoral researcher in Zavattieri’s group.

In the gas turbines of aircraft, for example, metals and composite materials are joined together with a mechanical fastener. This fastener adds weight and introduces stress that could lead to fractures and corrosion.

“These fasteners ultimately decrease the performance of the system and need to be replaced every so often. But the interfacial sutures of the diabolical ironclad beetle provide a robust and more predictable failure that could help solve these problems,” said Maryam Hosseini, who worked on this project as a Ph.D. student and postdoctoral researcher in Zavattieri’s group. Hosseini is now an engineering manager at Procter & Gamble Corp.

UCI researchers built a carbon fiber composite fastener mimicking a diabolical ironclad beetle’s suture. Purdue researchers found through loading tests that this fastener is just as strong as a standard aerospace fastener, but significantly tougher.

“This work shows that we may be able to shift from using strong, brittle materials to ones that can be both strong and tough by dissipating energy as they break. That’s what nature has enabled the diabolical ironclad beetle to do,” Zavattieri said.

This research is financially supported by the Air Force Office of Scientific Research and the Army Research Office through the Multi-University Research Initiative (award number FA9550-15-1-0009). The study used resources at the Advanced Light Source, a U.S. Department of Energy Office of Science User Facility.

Unique Australian spider silk


This 2018 video about food is called Spider Web Cake with Chocolate Ganache.

From the University of Melbourne:

Tapping secrets of Aussie spider’s unique silk

Silk so robust potential new genetic material touted

October 19, 2020

Summary: The basket-web spider, which is found only in Australia, has revealed it not only weaves a unique lobster pot web but that its silk has elasticity and a gluing substance, that creates a high degree of robustness.

An international collaboration has provided the first insights into a new type of silk produced by the very unusual Australian basket-web spider, which uses it to build a lobster pot web that protects its eggs and trap prey.

The basket-web spider weaves a silk that is uniquely rigid and so robust that the basket-web doesn’t need help from surrounding vegetation to maintain its structure.

“As far as we know, no other spider builds a web like this,” said Professor Mark Elgar from the School of BioSciences at the University of Melbourne.

“This silk retains its rigidity, allowing a rather exquisite silken basket or deadly ant trap.”

The collaboration between the University of Melbourne and the University of Bayreuth with the Australian Nuclear Science and Technology Organisation is likely to draw a lot of interest.

Entomologist William J Rainbow discovered the basket-spider in 1900 but made no mention of the nature of its silk, perhaps because he had only seen drawings of the web and imagined it to be more sack-like.

The recent study, just published in Scientific Reports, as Dimensional stability of a remarkable spider foraging web achieved by synergistic arrangement of silk fiber,” has found that the silk used to construct the basket web is similar to the silk that many species of spiders use to wrap around their eggs, to protect them from the elements and enemies.

“Our discovery may provide insights into the evolution of foraging webs,” said Professor Elgar. “It is widely thought that silk foraging webs, including the magnificent orb-webs, evolved from the habit of producing silk to protect egg cases. Perhaps the basket-web is an extension of the protective egg case and represents a rare contemporary example of an evolutionary ancestral process.”

The basket-web spider is found only in Australia. Its basket is approximately 11mm in diameter and 14 mm deep and has crosslinked threads of varying diameters. The nature of the silk was revealed by the Australian Synchrotron, a national facility of the Australian Nuclear Science and Technology Organisation in south east Melbourne.

Professor Thomas Scheibel from the University of Bayreuth said the rigidity of the silk appears to come from the synergistic arrangement of microfibres and submicron fibres.

“Nature has created a complex structure that, at first glance, resembles industrially produced composites,” said Professor Scheibel who headed the research from Germany.

“Further investigations have, however, shown that they are chemically different components and their respective properties together result in the thread’s extreme elasticity and toughness, thus creating a high degree of robustness. With today’s composite materials, on the other hand, it is mainly the fibres embedded in the matrix that establish the particular properties required, such as high stability.”

While more work needs to be done to understand the molecular details of the silk, Professor Scheibel said there is potential interest in a new genetic material that can be produced in a scalable manner.

“The interesting feature is the high lateral stiffness as well as the gluing substances, which could be useful in several types of applications but it will be some time before this becomes a possibility.”

Professor Elgar said “More generally the basket web, and the properties of its silk, highlight the importance of continuing to investigate obscure, unfamiliar species.

“There is increasing recognition that solutions to many of the complex challenges and puzzles we face today can be found from biological systems.

“This so-called ‘Bioinspiration’ draws on some 3.8 billion years of natural selection honing biological forms, processes and systems. The potential insights from that diversity of life, about which we still know rather little, is staggering.”

Coral reef decline in Hong Kong


This 2015 video is called Hong Kong coral reef thrives despite pollution.

From The University of Hong Kong:

Was Hong Kong once a coral reef paradise?

October 15, 2020

Researchers from The University of Hong Kong’s School of Biological Sciences and The Swire Institute of Marine Science, have for the first time investigated the historical presence of coral communities in the Greater Bay Area, revealing a catastrophic range collapse and loss of diversity that occurred in the last several decades.

The research, published in the journal Science Advances, looks at fossil corals collected from over 11 sites around Hong Kong, and creates the first palaeoecological baseline for coral communities in the Greater Bay Area. Led by PhD candidate and National Geographic Explorer Jonathan CYBULSKI, the team revealed what coral genera were present in the past well before major human impacts, and these include: Acropora, Montipora, Turbinaria, Psammacora, Pavona, Hydnophora, Porites, Platygyra, Goniopora and Faviids.

Every fossil tells a story

“The data we collect helps us to create a sort of fossil time machine,” said Cybulski. “As corals grow naturally, parts of them will break off and fall to seafloor becoming a part of the sediment. Over time, many different layers of these coral skeletons will stack on top of one another. With a bit of effort we can core through the sediments and collect the different layers and reveal what coral communities were like through time,” Cybulski explained. By using this method, the team was able to collect skeletons from over 5,000 years ago, which they determined thanks to radiocarbon dating by collaborator Dr Yusuke YOKOYAMA of the Atmosphere and Ocean Research Institute at The University of Tokyo.

When the team compared their fossil data to a modern-day dataset collected by collaborators at Baptist University — Dr Jian Wen QIU and Dr James XIE, several striking conclusions were revealed. First, there has been about a 40% decrease in the number of different corals living in Southern Hong Kong waters. Second, the greatest loss was of the ecologically important yet highly-sensitive staghorn corals (Acropora), which now only lives in an area about 50% smaller than its historic range. Finally, the greatest impact and losses of corals occurred in waters that are closest to the Pearl River Estuary in the southwest and Tolo Harbor in the Northeast. Based on the data, the teams best guess for the timing of this coral community change is conservatively within the last century, but likely within the past few decades. The overall conclusion: poor water quality driven by increased development and lack of proper treatment is presently the regions greatest threat to the survival of corals.

More hope for corals

“This trend we saw of a diversity decline and the loss of Acropora is consistent with other research in different areas of the world,” Cybulski continues: “It’s particularly bad news for this region, as Acropora represents the only type of coral that is complex, and creates physical space that promotes greater biodiversity. The loss of this coral is similar to losing all the big trees in a forest.” However, similar to trees in a forest, Cybulski continued by saying there is hope for Hong Kong’s corals through conservation efforts.

Indeed, this historical research has already played a critical role in protecting and restoring corals locally. In July earlier this year, PhD Candidate Ms Vriko YU, also of the Baker Lab at HKU, pioneered a coral restoration project in Hoi Ha Wan Marine Park (Note 1). This project aims to restore and better understand what it will take to save Hong Kong corals, and was made possible due to the water quality improvements in the bay by the local government.

Using Cybulski’s historical data to infer the appropriate steps needed, the team is now returning corals such as Acropora that previously thrived in Hoi Ha, back to their proper home. To date, 100% of the reintroduced coral have survived. Furthermore, the team has documented several coral-associated invertebrates at the site, showing that this restored habitat is indeed increasing biodiversity. The team feels this multi-faceted model — historical research that identifies major stress targets for local improvements — can be used by other researchers who hope to give corals their greatest chance for future survival.

Mysterious young sea stars, new research


Valvaster striatus sea stars

From the Smithsonian Tropical Research Institute in Panama, 13 October 2020:

Sea star’s ability to clone itself may empower this mystery globetrotter

October 13, 2020

Summary: The identity of wild cloning sea star larvae has been a mystery since they were first documented in the Caribbean. The most commonly collected cloning species was thought to belong to the Oreasteridae, on the basis of similarity with sequences from Oreaster reticulatus and Oreaster clavatus.

For decades, biologists have captured tiny sea star larvae in their nets that did not match the adults of any known species. A Smithsonian team recently discovered what these larvae grow up to be and how a special superpower may help them move around the world. Their results are published online in the Biological Bulletin.

“Thirty years ago, people noticed that these asteroid starfish larvae could clone themselves, and they wondered what the adult form was,” said staff scientist Rachel Collin at the Smithsonian Tropical Research Institute (STRI). “They assumed that because the larvae were in the Caribbean the adults must also be from the Caribbean.”

Scientists monitor larvae because the larvae can be more sensitive to physical conditions than the adults and larval dispersal has a large influence on the distribution of adult fishes and invertebrates. Collin’s team uses a technique called DNA barcoding to identify plankton. They determine the DNA sequence of an organism, then look for matches with a sequence from a known animal in a database.

“This mystery species was one of the most common in our samples from the Caribbean coast of Panama,” Collin said. “We knew from people’s studies that the DNA matched sequences from similar larvae across the Caribbean and it matched unidentified juvenile starfish caught in the Gulf of Mexico — but no one had found a match to any known adult organism in the Caribbean. So we decided to see if the DNA matched anything in the global ‘Barcode of Life’ data base.”

“That’s when we got a match with Valvaster striatus, a starfish that was thought to be found only in the Indo West Pacific,” Collin said. “The is the first-ever report of this species in the Atlantic Ocean. We could not have identifed it if Gustav Paulay from the University of Florida didn’t have DNA sequences from invertebrates on the other side of the world.”

But why are the larvae common in the Caribbean if adult Valvaster starfish have never been found here? Are the adult starfish hidden inside Caribbean reefs, or are the larvae arriving from the other side of the world?

V. striatus is widespread but rare in the western Pacific. The few reports from collectors and the confirmed photos on iNaturalist range from the Indian Ocean to Guam and Hawaii. These starfish live deep in the reef matrix, only coming out at night. So, it is possible that there are adults in the Caribbean that have never been seen. But the other possibility, that the ability to clone themselves may allow them to spread around the world, is also intriguing.

“It’s possible that the ability of the larvae to clone themselves is not just a clever way to stay forever young,” Collin said. “There’s a natural barrier that keeps organisms from the western Pacific and the Indian ocean from crossing the Atlantic to the Caribbean. After they make it around the tip of Africa, they are met by a cold current that presumably kills tropical species.”

“Just how cloning could help them get through the barrier is still not known, but it’s intriguing that another sea star species from the Indo West Pacific that was collected for the first time in the Caribbean in the 1980s also has cloning larvae,” Collin said.

Crabs, ecology and economy in Oman


This February 2019 video is about saving an Omani crab which had got caught in a fishing net.

From the Royal Netherlands Institute for Sea Research:

Crabs are key to ecology and economy in Oman

Importance of crabs should be considered when looking at increasing human pressure on Barr Al Hikman nature reserve

October 8, 2020

The intertidal mudflats of Barr Al Hikman, a nature reserve at the south-east coast of the Sultanate Oman, are crucial nursery grounds for numerous crab species. In return, these crabs are a vital element of the ecology, as well as the regional economy, a new publication in the scientific journal Hydrobiologia shows. ‘These important functions of the crabs should be considered when looking at the increasing human pressure on this nature reserve’, first author and NIOZ-researcher Roeland Bom says.

Blue swimming crab

The mudflats of Barr Al Hikman are home to almost thirty crab species. For his research, Bom, together with colleagues in The Netherlands and at the Sultan Qaboos University in Oman, looked at the ecology of the two most abundant species. Bom: ‘Barr Al Hikman is also home to the blue swimming crab Portunus segnis. That is the species caught by local fishermen. This crab uses the mudflats of Barr Al Hikman as nursery grounds.’

The counts of Bom and his colleagues show, that there are millions and millions of these crabs in Barr Al Hikman. They are food to hundreds of thousands of birds, both migrating species, as well as birds breeding in the area, such as crab plovers. The crabs live in holes in the ground. They forage on the seagrass beds that are still abundant in Barr Al Hikman. ‘Apart from the high primary production (algae) in Barr al Hikman, this reserve is also well suited for crabs because of the vastness of the area’, Bom assumes. ‘The slopes of the mudflats are very gentle, so at low tide, the crabs have an immense area at their disposition.’

Eco value

The value of the crabs is not just ecological, Bom stresses. “Local fishermen that catch the blue swimming crabs, distribute them not only through Oman, but also through the rest of the Arabian Peninsula and even to Japan. At approximately € 2,- per kilo, these crabs represent an important economic pillar, both under the region around Barr Al Hikman, as well as for the whole of Oman.’

Reserve

The protection of the reserve of Barr Al Hikman is limited to national legislation. Efforts to acknowledge this reserve under the international Ramsar-convention were never effectuated. There is, however, increasing human pressure on the mudflats of Barr Al Hikman, the authors describe, that would justify further protection. For example, there are well-developed plans to start shrimp farming around this intertidal area. ‘When looking at the cost and benefits of these activities, it is important to look at the role of this reserve in the local ecology, as well as in the broader ecology of the many migratory birds that use the area’, Bom says. ‘Moreover, our research shows that the unique ecosystem of Barr Al Hikman plays a key role in the economy as well.’