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Scientists Just Discovered 3 New Kinds of Carnivorous Sponge in The Deep Ocean

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Even though we know the deep sea is weird, ‘carnivorous sea sponges’ still sound like something from a sci-fi movie. And yet, researchers just announced the discovery of three new such species off the coast of Australia.

 

Go a few hundred metres deep into the ocean, and it starts to look like you’re in a whole new world: From a creature that looks like a sea star crossed with an octopus, to shark-devouring fish, to carnivorous sponges we’ve never seen before.

“It just goes to show how much of our deep oceans are yet to be explored – these particular sponges are quite unique in that they are only found in this particular region of The Great Australian Bight – a region that was slated for deep sea oil exploration,” said one of the researchers, Queensland Museum Sessile Marine Invertebrates Collection manager Merrick Ekins.

Typically, sea sponges are multicellular filter feeders – they have holey tissues for flowing water, from which their cells extract oxygen and food. They’re pretty simple creatures, with no nervous, digestive, or circulatory system, but have existed in some form for over 500 million years.

SAM S2599 MOD 2Scanning electron microscope image of Abyssocladia oxyasters. (Ekins et al., Zootaxa, 2020)

But carnivorous sponges are a bit different. Some carnivorous sponges still use the water flow system, while others (like the three newly discovered species) have lost this ability altogether, and nab small crustaceans and other prey using filaments or hooks.

The researchers in this study found three new species of carnivorous sponges – Nullarbora heptaxia, Abyssocladia oxyasters and Lycopodina hystrix, which are also all new genera, as well as a closely related species of sponge that isn’t carnivorous, Guitarra davidconryi. All these species were found at depths of between 163 and over 3,000 metres (535 to 9,842 feet) deep.

 

“Here we report on an additional four new species of sponges discovered from the Great Australian Bight, South Australia. This area has recently been surveyed, using a Smith-McIntyre Grab and a Remotely Operated Vehicle (ROV) to photograph and harvest the marine biota,” the researchers write in their new paper.

“These new species are the first recorded carnivorous species from South Australia and increase the number of species recorded from around Australia to 25.”

The sponges are also prettier than you would imagine, looking a little like flowers with their spiky protrusions, but not a lot like sponges. 

SAM S2599 MOD 3Close up of A. oxyaster. (Ekins et al., Zootaxa, 2020)

Carnivorous sponges are having a bit of a moment. We’ve known about them since 1995, but many more have recently been discovered around the world.

“Over the past two decades, our knowledge of carnivorous sponge diversity has almost doubled,” the same team explains in an earlier paper, where they described their discovery of 17 new species of carnivorous sponges.

“[This is] due in part to rapid advances in deep sea technology including ROVs and submersibles able to photograph and harvest carnivorous sponges intact, and also to the herculean efforts of a number of contemporary taxonomists redescribing many of the older species described in the 19th and 20th centuries.”

Nearly every species of carnivorous sponge found in Australia was discovered during a CSIRO RV Investigator Voyage in 2017, showing just how important these deep-sea investigations are.

With the bottom of the ocean still mostly unexplored, we imagine we’ll see plenty more species of carnivorous sponges, and other weird and wonderful sea creatures. 

The research has been published in Zootaxa.

 



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Octopuses May Be Adapting to The Rising Acidity of Our Oceans, Study Suggests

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We know that all the excess CO2 we’re pumping into the air – alongside a host of other damaging effects – is driving up the acidity of the oceans as it sinks and dissolves into the water, but it seems as though the hardy octopus can find ways to adapt to its rapidly changing environment.

 

Previous research into the impact of ocean acidification on cephalopods such as octopuses, cuttlefish, and squid has shown some indication increased carbon dioxide in the water could negatively impact this type of marine life.

However, in a new study, a group of Octopus rubescens – a species of octopus common to the west coast of North America – were observed adjusting their routine metabolic rate (RMR) over a series of weeks in response to lowering pH levels in the surrounding water.

“Challenges to an organism’s physiology are often reflected in changes in energy use and therefore can be observed as changes in aerobic metabolic rate,” write the researchers in their paper.

A total of 10 octopuses were studied under controlled lab conditions, with RMR measured immediately after exposure to acidic water, after one week, and after five weeks. Critical oxygen pressure – a measure of whether not not animals are getting enough oxygen – was monitored at the same time.

To begin with, high levels of metabolic change were detected in the creatures – a sort of shock reaction that actually conflicts with earlier research into cephalopods, which had recorded a reduction in metabolic change in similar scenarios.

 

However, RMR had returned to normal after one week, and remained the same five weeks later, suggesting some adaptation had occurred. The increased acidity did have an impact on the ability of the octopuses to function at low oxygen levels, however.

“This response in RMR suggests that O. rubescens is able to acclimate to elevated CO2 over time,” write the researchers. “The observed increase in RMR may be the result of multiple acute responses to hypercapnia [increased CO2 in the blood], possibly including both behavioural and physiological strategies.”

Those strategies could include preparing to move to find a new stretch of water to inhabit, for example, the researchers suggest (something that wasn’t possible here). The short RMR boost might also reflect the octopuses making quick adjustments to their biological processes to suit the new acid level.

The study is the first to look at both short-term (one week) and longer-term (five week) changes in metabolism rates in cephalopods in response to ocean acidification. We know these creatures are tough, and it seems they even have coping strategies that might allow them to adapt to humans destroying the natural environment all around them.

None of this means that we should be okay with the current climate crisis though, or not be trying to make major changes to reverse it. When we don’t take proper care of the planet, it’s not just ourselves that we’re potentially dooming to extinction.

Also, these tests were done in controlled laboratory conditions that don’t take into account many other interlinking factors in the animals’ natural environment. For instance, even if the octopus themselves are able to adjust, what about their food supply?

“While this species may be able to acclimate to near-term ocean acidification, compounding environmental effects of acidification and hypoxia may present a physiological challenge for this species,” write the researchers.

The research has been published in Physiological and Biochemical Zoology.

 



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We Need to Talk About The Rapid Decline in Insects Around The World

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Apocalypse or revolution? Depending on the study making headlines, insect numbers around the world are either in dramatic freefall or simply an alarming state of flux, with some species even benefiting from changes in climate.

 

While researchers debate the details, most are in agreement that our existing lifestyle is fundamentally linked with insect numbers, and unless we act fast, we can expect trouble in the future.

In a series of papers published in the latest Proceedings of the National Academy of Sciences (PNAS), experts sum up the state of insect numbers as a measure of biomass, individual numbers, and species. And no matter which way we cut it, it’s an issue we really need to get on top of.  

Saul Cunningham from the Australian National University wasn’t one of the 56 authors contributing to the commentary. But as Director of the Fenner School of Environment & Society at the university, he’s aware of just how important insects are to our communal wellbeing.  

“Insects are hugely important to ecological processes that humans rely on, including the provision of food and recycling of nutrients into the soil,” says Cunnigham.

“That is why they have been described as the little things that run the world.”

Those ‘little things’ have been running vital ecological processes for hundreds of millions of years, diversifying into more than a million extant species. And that’s just the ones we’ve counted. It’s hard to imagine a world without them.

 

Yet in recent decades the ranges and proportions of many species have dipped significantly, most likely due to factors such as changing temperatures, rainfall, habitat loss, and pesticide use.

Most commonly cited statistics put estimates of insect biomass loss at around 1 to 2 percent per annum – a shocking figure made all the more alarming when local variations are taken into account, with some areas seeing losses of 10 percent or more every year.

“They also show that insect declines are not universal, with losses not apparent for some other regions,” says Cunnigham.

“The studies add significant urgency to the case that we need to develop agricultural practices that support healthy and diverse insect populations.”

Not only is the decline not universal, in some parts of the globe insects are having a hey-day. Especially in temperate climates, many species are booming, most likely due to rising temperatures pushing ranges of habitat out towards the poles.

It’s a great time to be alive if you’re a southern British species of moth, for example. With environmental protection laws cleaning up waterways, populations of aquatic bugs and beetles are on the rise.

 

But just because the big picture is complicated, it doesn’t mean we ought to be complacent. For one thing, the loss of even a few less robust species in the midst of global climate change could be a sign that worse is to come.

As to thriving insect populations, a surplus of moths, water-striders and cockroaches won’t mean much when crops fail in the wake of lost pollinators, or garbage overflows for want of specialist detritivores.

Entomologist Akito Kawahara from the Florida Museum of Natural History co-authored one of the journal’s opinion pieces, urging communities to do more to ensure there are plenty of creepy-crawlies around to continue their hard work.

“In the US alone, wild insects contribute an estimated US$70 billion to the economy every year through free services such as pollination and waste disposal. That’s incredible, and most people have no idea,” says Kawahara.

He and his team outlined a handful of simple actions we can all undertake to do our bit to ensure local biodiversity remains strong.

For example, keeping outside lights off at night, or switching bulbs to avoid luring insects away from habitats where they’re doing more good; washing your car and driveway with biodegradable soaps, and using soy-based driveway sealants.

 

Some of the suggestions don’t even require lifting a hand. Got a lawn? Hold off on mowing for a few weeks. Better still, rip up a portion of it and replace with some natives. Kawahara recommends reserving a chunk of your yard space for insects, which means no pesticide and plenty of choice in vegetation.

“If every home, school and local park in the US converted 10 percent of lawn into natural habitat, this would give insects an extra 4 million acres of habitat,” he advises.

Hopefully, 2021 will see even more studies on insect numbers in flux around our planet, painting a complex scene of species in freefall and others breaking new ground. We’re going to need all the information we can get.

“We can learn from those places that are not witnessing dramatic insect declines,” says Cunnigham.

“Globally we are not monitoring insect populations in a widespread or systematic way, which limits our power to respond.”

This research was published in PNAS.

 



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Why Some of Darwin’s Finches Evolved to Become Vampire Finches

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For most people, the word “vampire” brings to mind Dracula or perhaps slayers such as Blade or Buffy; or maybe even the vampire bats of South America. Few will think of a small and rather lovely bird – the finch.

 

But there are indeed “vampire finches” that feast on the blood of much larger birds, and they were introduced to the world in a fantastic segment of Perfect Planet, the new series narrated by David Attenborough for the BBC. For us, these finches needed no introduction as we have studied them closely.

These birds are found on the Galápagos Islands, a volcanic archipelago located about 1,000 kilometres (600 miles) off the coast of Ecuador. The islands are a biodiversity hotspot in part because of their isolation. Organisms that somehow make it to the Galápagos must adapt to the harsh conditions or go extinct.

One such group of organisms is the Darwin’s finches. Named after the naturalist Charles Darwin, who collected examples on his famous voyage aboard the HMS Beagle, this group of finches consists of several species that have evolved from a common ancestor.

Each species has evolved a different bill size and shape which allows it to exploit different food items. For example, the cactus finch has a long thin bill that allows it to consume the nectar from of cactus flowers. Some species have bills that are better at crushing seeds, while others are better at consuming insects or plants.

It makes sense that different species of finches evolved to feed on different types of food items on the Galápagos, but where did blood-feeding come from?

 

How blood-sucking evolved

The vampire finches are found only on Wolf and Darwin, the two northernmost islands of the archipelago and remote even by Galápagos standards. Both islands are tiny, each less than a square mile, and are separated from the larger islands by 100 miles of open ocean. Freshwater is extremely rare and some food can disappear entirely during the dry season.

At some point in the last half-million years – recent in evolutionary terms – finches arrived on Wolf and Darwin and began to co-exist with large seabirds which nest on the islands, such as red-footed and Nazca boobies.

Over time, it seems the finches likely evolved to eat parasites found in the feathers and on the skin of the boobies. This was “mutualism” in action: the boobies benefited from parasite removal, and the finches benefited by having an alternative to their usual diet of nectar, seeds, and insects which can disappear during the dry season.

Eventually, however, the removal of parasites led to open skin lesions on the boobies, allowing the finches to consume blood.

 

The finches even learned to pierce skin at the base of young feathers to access the blood directly, no longer needing the insect parasites anymore. Thus, the finches capitalised on an alternative food resource, blood from the boobies, and earned themselves the nickname “vampire finches”.

It’s hard to know exactly how much of the finch’s diet is booby blood, but our unpublished data suggests it’s about a tenth.

Natural selection appears to have fine-tuned the vampire finch beak for skin-piercing and blood-sucking, as the birds have evolved particularly long and pointy beaks compared to non-blood-feeding populations on other islands. And once a blood-feeder pierces the skin, it still needs a way to consume and digest the blood.

When we studied the microbes found in the guts of these vampire finches in search of adaptations we found a very different microbiome from any other species of Darwin’s finches, presumably caused by the blood diet.

What it’s like to see in person

Two of us, Daniel and Jaime, visited Darwin and Wolf to study these fascinating finches on islands that are very rarely visited, even by researchers.

Getting there was extremely challenging as there are no beaches for landing a boat. We had to approach the cliffs in a small dinghy and then wait for a brief gap in the waves before jumping onto sharp, black lava rocks.

 

But this isolation means the vampire finches are plentiful, and the dense breeding colonies of boobies made it easy to envision how this strange blood-sucking behaviour could have evolved.

The boobies are incredibly vulnerable when tending to nests and chicks, as they are reluctant to abandon them, even temporarily.

We observed scores of vampire finches clamouring all over the backs, tails, and wings of boobies, opening up substantial wounds with their sharp beaks, and drinking their fill of blood.

Interestingly, the finches seem to act like a true parasite, inflicting enough damage to secure a meal without excessively harming the host.

For the boobies, the whole experience really is very similar to a human being attacked by mosquitos. Though they can tolerate the finches, the small bloodsuckers are a nuisance that the boobies do try to get rid of. And when it all gets too much, they can be forced to fly away.

And who can blame them? When we captured finches to collect samples, and found gullets full of blood, and beaks stained red. It was evident that the little vampires were not merely lapping up a few drops of blood. The Conversation

Kiyoko Gotanda, Postdoctoral Research Fellow, Université de Sherbrooke and, University of Cambridge; Daniel Baldassarre, Assistant Professor of Zoology, State University of New York Oswego, and Jaime Chaves, Assistant Professor, Ecology and Evolution, San Francisco State University.

This article is republished from The Conversation under a Creative Commons license. Read the original article.

 





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How a Science Fight Finally Led to World’s First Global Species List in 2020

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Taxonomy, or the naming of species, is the foundation of modern biology.

It might sound like a fairly straightforward exercise, but in fact it’s complicated and often controversial. Why? Because there’s no one agreed list of all the world’s species.

 

Competing lists exist for organisms such as mammals and birds, while other less well-known groups have none. And there are more than 30 definitions of what constitutes a species. This can make life difficult for biodiversity researchers and those working in areas such as conservation, biosecurity and regulation of the wildlife trade.

In the past few years, a public debate erupted among global taxonomists, including those who authored and contributed to this article, about whether the rules of taxonomy should be changed. Strongly worded ripostes were exchanged. A comparison to Stalin was floated.

But eventually, we all came together to resolve the dispute amicably. In a paper published in July, we proposed a new set of principles to guide what one day, we hope, will be a single authoritative list of the world’s species. This would help manage and conserve them for future generations.

In the process, we’ve shown how a scientific stoush can be overcome when those involved try to find common ground.

How it all began

In May 2017 two of the authors, Stephen Garnett and Les Christidis, published an article in Nature. They argued taxonomy needed rules around what should be called a species, because currently there are none. They wrote:

for a discipline aiming to impose order on the natural world, taxonomy (the classification of complex organisms) is remarkably anarchic […] There is reasonable agreement among taxonomists that a species should represent a distinct evolutionary lineage. But there is none about how a lineage should be defined.

‘Species’ are often created or dismissed arbitrarily, according to the individual taxonomist’s adherence to one of at least 30 definitions. Crucially, there is no global oversight of taxonomic decisions — researchers can ‘split or lump’ species with no consideration of the consequences.

Garnett and Christidis proposed that any changes to the taxonomy of complex organisms be overseen by the highest body in the global governance of biology, the International Union of Biological Sciences (IUBS), which would “restrict […] freedom of taxonomic action.”

 

An animated response

Garnett and Christidis’ article raised hackles in some corners of the taxonomy world – including coauthors of this article.

These critics rejected the description of taxonomy as “anarchic”. In fact, they argued there are detailed rules around the naming of species administered by groups such as the International Commission on Zoological Nomenclature and the International Code of Nomenclature for algae, fungi, and plants. For 125 years, the codes have been almost universally adopted by scientists.

So in March 2018, 183 researchers – led by Scott Thomson and Richard Pyle – wrote an animated response to the Nature article, published in PLOS Biology.

They wrote that Garnett and Christidis’ IUBS proposal was “flawed in terms of scientific integrity […] but is also untenable in practice”. They argued:

Through taxonomic research, our understanding of biodiversity and classifications of living organisms will continue to progress. Any system that restricts such progress runs counter to basic scientific principles, which rely on peer review and subsequent acceptance or rejection by the community, rather than third-party regulation.

In a separate paper, another group of taxonomists accused Garnett and Christidis of trying to suppress freedom of scientific thought, likening them to Stalin’s science advisor Trofim Lysenko.

 

Finding common ground

This might have been the end of it. But the editor at PLOS Biology, Roli Roberts, wanted to turn consternation into constructive debate, and invited a response from Garnett and Christidis. In the to and fro of articles, we all found common ground.

We recognised the powerful need for a global list of species – representing a consensus view of the world’s taxonomists at a particular time.

Such lists do exist. The Catalogue of Life, for example, has done a remarkable job in assembling lists of almost all the world’s species. But there are no rules on how to choose between competing lists of validly named species. What was needed, we agreed, was principles governing what can be included on lists.

As it stands now, anyone can name a species, or decide which to recognise as valid and which not. This creates chaos. It means international agreements on biodiversity conservation, such as the Convention on International Trade in Endangered Species (CITES) and the Convention on the Conservation of Migratory Species of Wild Animals (CMS), take different taxonomic approaches to species they aim to protect.

 

We decided to work together. With funding from the IUBS, we held a workshop in February [2020] at Charles Darwin University to determine principles for devising a single, agreed global list of species.

Participants came from around the world. They included taxonomists, science governance experts, science philosophers, administrators of the nomenclatural (naming) codes, and taxonomic users such as the creators of national species lists.

The result is a draft set of ten principles that to us, represent the ideals of global science governance. They include that:

  • the species list be based on science and free from “non-taxonomic” interference
  • all decisions about composition of the list be transparent
  • governance of the list aim for community support and use
  • the listing process encompasses global diversity while accommodating local knowledge.

The principles will now be discussed at international workshops of taxonomists and the users of taxonomy. We’ve also formed a working group to discuss how a global list might come together and the type of institution needed to look after it.

We hope by 2030, a scientific debate that began with claims of anarchy might lead to a clear governance system – and finally, the world’s first endorsed global list of species.

The following people provided editorial comment for this article: Aaron M Lien, Frank Zachos, John Buckeridge, Kevin Thiele, Svetlana Nikolaeva, Zhi-Qiang Zhang, Donald Hobern, Olaf Banki, Peter Paul van Dijk, Saroj Kanta Barik and Stijn Conix. The Conversation

Stephen Garnett, Professor of Conservation and Sustainable Livelihoods, Charles Darwin University; Les Christidis, Professor, Southern Cross University; Richard L. Pyle, Associate lecturer, University of Hawaii, and Scott Thomson, Research associate, Universidade de São Paulo.

This article is republished from The Conversation under a Creative Commons license. Read the original article.

 



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Prehistoric ‘Hell Ant’ Stuck in Amber Has Been Biting Its Prey For 99 Million Years

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A long-extinct lineage of insect, known fondly as the ‘hell ant’, has been discovered frozen in 99-million-year-old amber, with its scythe-like jaw still pinning its prey.

According to scientists, this fierce predator is a newly identified species of prehistoric ant, known as Ceratomyrmex ellenbergeri, and it’s the first time we’ve ever seen a hell ant actively feeding. Its meal is an extinct relative of the cockroach.

 

“Fossilised behaviour is exceedingly rare, predation especially so,” says Phillip Barden, who studies social insect evolution at the New Jersey Institute of Technology (NJIT).

“As palaeontologists, we speculate about the function of ancient adaptations using available evidence, but to see an extinct predator caught in the act of capturing its prey is invaluable.”

Ants are some of the most diverse creatures on planet Earth. To date, scientists have identified over 12,500 different species and they think there are probably another 10,000 or so out there, just waiting to be discovered underfoot.

That’s quite the selection. And yet of all the ants marching today, none of them look anything like what scientists have found in amber deposits from Myanmar, Canada, and France

In fact, Barden says the mouthparts of these haidomyrmecine hell ants are unlike that of nearly all insects alive today. This newly-identified hell ant used its lower mandible to move upwards and pin its prey to the horn-like paddle above. 

Other hell ants discovered in the past also have this horn, and while scientists thought it might be a sort of clamp, this 99-million-year-old fossil is the first real evidence that can back that up. 

 

Contrary to these ancient bugs, modern ants and almost all other living hexapods have mandibles that only move on a horizontal axis.

“Since the first hell ant was unearthed about a hundred years ago, it’s been a mystery as to why these extinct animals are so distinct from the ants we have today,” Barden says.

“This fossil reveals the mechanism behind what we might call an ‘evolutionary experiment,’ and although we see numerous such experiments in the fossil record, we often don’t have a clear picture of the evolutionary pathway that led to them.”

Fossilized Predation (Barden et al., Current Biology, 2020)

Above: The hell ant Ceratomyrmex ellenbergeri grasping a nymph of Caputoraptor elegans (Alienoptera) preserved in amber dated to roughly 99 million years.

Hell ants actually precede the most common ancestor of all living ants, and even then, they were incredibly diverse.

Other species trapped in amber have been found equipped with spiky mouthparts, most probably used to drink their victims’ blood.

Modern ants, on the other hand, look remarkably different. They have mouths facing forward, which keeps their heads relatively parallel to the ground, although they can look up and around.

Hell ants couldn’t move their heads nearly as well, and they likely captured prey with their mouths facing downwards.

illustrationhellantA simplified reconstruction of the hell ant eating from a lateral view. (Barden et al., Current Biology, 2020)

“Despite staggering anatomical diversity of insects, larval dytiscid beetles and hell ants together appear to represent the only two known instances of mandible-on-head contact used in prey capture, both appearing with vertically articulating mouthparts,” the authors write.

Why exactly hell ants died out as a lineage after nearly 20 million years of existence is still unknown, but it might have to do with their specialised predatory behaviour.

Barden says it just goes to show that even the most diverse and ubiquitous species on Earth can go extinct. Even something as familiar as an ant.

The study was published in Current Biology.

A version of this article was first published in August 2020.

 



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A New Species of Bat Has Been Found, And It Flapped Around 16 Million Years Ago

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There are a lot of bat species in the world today. Like, a ton of bats. We know of at least 1,400 species, and they make up around 20 percent of all current mammal species. It’s the bats’ world, we just live in it.

 

However, despite bats seemingly exploding onto the scene during the Eocene (the earliest bat fossil dates back to 52 million years ago), in a rapid diversification that has been described as “unprecedented”, the bat fossil record is notoriously poor.

Any new find is incredibly valuable, helping to fill in the gaps in our understanding of their wild evolution. That’s what a team of scientists led by palaeontologist Vicente Crespo of the La Plata Museum in Argentina has just found.

From the Ribesalbes-Alcora Basin in the Castellón province of Spain, the researchers have recovered the remains of ten bats – including those of a new species previously unknown to science.

“This constitutes, thus far, the first and largest collection of fossil bats from the early Miocene of the Iberian Peninsula,” the team wrote in their paper.

They have named their new species Cuvierimops penalveri, in honour of palaeontologist Enrique Peñalver of the University of Valencia.

The fossil assemblage in which the bats were found dates back to over 16 million years ago, during the height of the Miocene, which ran from around 23 million to 5 million years ago. By the time the Miocene rolled around, mammals were already fairly well established; the fossil site once resembled a tropical forest, and numerous species of animals – including shrews, squirrels, dormice, hamsters and crocodiles – have been found fossilised there.

But the newly found bats are incredibly interesting, the researchers said.

new bat teethFossilised teeth used to identify some of the bats. (Crespo et al., Earth Environ Sci Trans R Soc Edinb, 2020)

That’s because, of the 10, five belong to the Molossid, or free-tailed, bat family. Today, these are abundant and highly diverse; in the Oligocene epoch, from around 34 million to 23 million years ago, they dominated the European bat scene. But from the Miocene, molossid fossils are scarce.

The new kid, C. penalveri, is one of these molossids. Its presence is even more intriguing. Of its genus, Cuvierimops, only one other species has been identified, dating back to the Oligocene at the latest. Palaeontologists thought that it must have gone extinct not long after.

 

Another of the molossids, Rhizomops cf. brasiliensis, marks the first recorded appearance of its genus in the Early Miocene.

And there was another special recovery – an individual of the genus Chaerephon. A number of Chaerephon species are alive today, but previously, no remains had been recovered older than about 12,000 years. Finding an individual dating back to 16 million years ago places the genus in the Lazarus bucket – species that disappear from the fossil record for a long time, only to reappear later alive and well.

The presence of so many molossids, the researchers note, confirms the ancient tropical forest interpretation of the region. Today, molossids are the most abundant and diverse in densely forested tropical areas that are also rich in squirrels, dormice, and insectivores.

Together, the new discoveries are helping us piece together a very incomplete puzzle about the history of bats.

“The richness of molossids recorded in this material reveals the high diversity attained by this group in the Miocene of Europe, which had been largely unrecognised as a result of such fossils being typically underrepresented in the .. fossil record,” the researchers wrote.

“The abundance of these bats in the Ribesalbes-Alcora Basin is consistent with the presence of a tropical forest surrounding a paleolake, as suggested also by the presence of other mammal taxa such as eomyids, certain types of dormouse, and insectivores.”

The research has been published in Earth and Environmental Science Transactions of the Royal Society of Edinburgh.

 



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Scientists Confirm Entirely New Species of Gelatinous Blob From The Deep, Dark Sea

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For the first time, scientists with the National Oceanic and Atmospheric Administration (NOAA) have formally identified a new species of undersea creature based solely on high-definition video footage captured at the bottom of the ocean.

 

And what an undersea creature it is. Meet Duobrachium sparksae – a strange, gelatinous species of ctenophore, encountered by the remotely operated vehicle (ROV) Deep Discoverer during a dive off the coast of Puerto Rico.

That encounter took place back in 2015, but when you’re laying claim to discovering a wholly new species – based solely on video evidence, for that matter, with no physical specimens to help make your case – it helps to do your due diligence.

010 ctenophore 2Duobrachium sparksae. (NOAA)

Luckily, Deep Discoverer‘s cameras – the footage of which you can see here – were up to the job, capable of picking up subtle details on D. sparksae‘s body less than a millimetre long.

Subsequent analysis of the organism – now detailed in a new paper – indicates it’s easily distinguishable from all other known ctenophore species, the researchers say.

“It’s unique because we were able to describe a new species based entirely on high-definition video,” explains NOAA marine biologist Allen Collins.

“We don’t have the same microscopes as we would in a lab, but the video can give us enough information to understand the morphology in detail, such as the location of their reproductive parts and other aspects.”

Those aspects are manifold. From a distance, D. sparksae‘s most notable feature is its bulbous, balloon-like body, but it also features two prominent tentacle arms.

In total, three different individuals were filmed by the ROV at depths of around 3,900 metres (almost 2.5 miles down), with one of the animals appearing to perhaps be using its tentacles to anchor itself to the seabed.

“It was a beautiful and unique organism,” says oceanographer Mike Ford.

 

“It moved like a hot air balloon attached to the seafloor on two lines, maintaining a specific altitude above the seafloor. Whether it’s attached to the seabed, we’re not sure. We did not observe direct attachment during the dive, but it seems like the organism touches the seafloor.”

The other specimens might not have been touching the seabed, but all three of the animals were spotted within two metres of it, in a feature called the Arecibo Amphitheater, which lies within an underwater trench known as the Guajataca Canyon.

It’s in these very deep parts of the ocean where ctenophores are found, but the extreme depth of their natural habitat means we don’t encounter these mysterious animals – let alone new species – very often.

Ctenophores go by a number of common names, many of which seem almost comical: comb jellies (named after their ‘combs’ of fine cilia) is the most popular, but they have also been referred to as sea gooseberries, sea walnuts, and Venus’s girdles.

010 ctenophore 2Digital illustrations of Duobrachium sparksae. (Nicholas Bezio).

While the animals can superficially resemble jellyfish, they are not closely related. Ctenophores, which are carnivorous, subsist on small arthropods and various kinds of larvae.

Up to about 200 species have been described to date, with about one new species being found each year on average, and most discoveries rely on video capture methods for the basis of physical descriptions, given the difficulties of collecting specimens.

 

“This presents somewhat of a conundrum because taxonomy relies heavily upon physical type specimens preserved in museums to serve as references to which other material can be compared,” the researchers explain in their paper.

“Indeed, the idea of using photographic evidence to establish new species has been highly contentious in recent decades.”

Luckily, given the high-definition footage the team got of these three fine specimens of D. sparksae, the researchers say they didn’t get “any pushback” about their species discovery.

While the team hopes to collect specimens on future dives for physical analysis, they say it might be decades before they have the chance to run into the comb jelly again.

For D. sparksae‘s sake, that might be for the best: bringing a gelatinous blob up to sea level, when it normally resides about 4 kilometres under the ocean’s surface, can be a messy affair.

“Even if we had the equipment, there would have been very little time to process the animal because gelatinous animals don’t preserve very well,” Collins says.

“Ctenophores are even worse than jellyfish in this regard.”

The findings are reported in Plankton and Benthos Research.

 



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Stop Everything – It Turns Out Wombats Also Have Biofluorescent Fur

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First we discovered platypus would look great at a rave, now wombats, bilbies and other marsupials can join the blacklight party – with scientists unexpectedly finding they all glow wonderfully fluorescent greens, blues and pinks beneath UV light.

 

Over the last few years scientists have found biofluorescence is more common across mammals than we realised – with flying squirrels that glow a bubblegum pink, prompting researchers to see how far back this trait exists in our mammalian heritage by checking out monotremes like the platypus (Ornithorhynchus anatinus) – the most ancient still living mammalian lineage.

Naturally, once the platypus’s glow was revealed, other researchers like Western Australian Museum curator of Mammalogy, Kenny Travouillon and biologist Linette Umbrello, started shining UV down on different species. 

And so far their findings have been far from disappointing, with revelations of neon wombats and bright-eared bilbies.

“We have only tried it on maybe two dozen mammals, so it wasn’t a thorough search.” Travouillon told ScienceAlert. “Probably around a third of them did glow.”

These included platypus (which they double checked), echidna, bandicoots and bilbies, possums and some bats. The Australian creatures join a host of other living things that biofluoresce, including insects, frogs, fish and fungi.

 

Biofluorescence occurs when a living thing absorbs high energy radiation such as ultraviolet and then emits light back out at a lower frequency. Many proteins have been identified that can do this in skin or in other animal tissues – including bones and teeth, Australian Museum wildlife forensic scientist Greta Frankham explained to ScienceAlert.

“There are chemical compounds in lots of different animal body parts that do seem to fluoresce, so it’s not surprising to find there may be other chemical compounds in other things like fur that fluoresce,” Frankham said.

Scientists have isolated some of these molecules and used them for scientific imaging, like the jellyfish’s green fluorescent protein.

The exact details of how and why biofluorescence occurs in these mammals is still to be determined. But however it’s achieved, it certainly produces some startlingly bright results under UV light, like the ears and tail of this Bilby (Macrotis leucura).

Bilbies are a nocturnal and endangered desert dwelling species that happens to like eating another animal that glows under UV – scorpions

Wombats and the endangered eastern barred bandicoot (Perameles gunnii) are also nocturnal species. Many of the biofluorescent mammals identified so far are either nocturnal or crepuscular (most active at dawn and dusk), but biofluorescence requires a light source for the glow to then re-emit from and there’s less of UV light around at night. 

“Perhaps they are able to see much more than we are able to see,” Travouillon hypothesised. 

 

“Predators don’t seem to glow. I think this is because if predators could be seen, they would lose all chance of catching their prey.”

Frankham pointed out however, that many marsupials are nocturnal, so this may not necessarily be a driving factor in evolution of this trait.

While there’s now much speculation about why some mammals glow under UV, we’ve only just realised how wide-spread the phenomenon is. So there’s a lot to do before we can glean any answers.

In response to the fuss over the glowing animals on social media, Lund University evolutionary biologist Michael Bok cautioned:

Field studies are required to examine if there even are any advantages or disadvantages of this ability within these animals’ natural environment – but given how vulnerable many of these Australian species are, it’s likely worth checking to see if this trait does impact their ecology or not.

“At this stage, we are all guessing why this is happening, so additional testing will be required to really understand what is going on,” Travouillon said. He’s planning to test more mammals with different lights and see if there really is a pattern with nocturnal mammals.

 





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Giant Search Confirms Charles Darwin’s Notebooks Are Missing, Presumed Stolen

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Two of Charles Darwin’s notebooks containing his pioneering ideas on evolution and his famous “Tree of Life” sketch are missing, believed stolen, the Cambridge University Library said on Tuesday.

 

The British scientist filled the leather notebooks in 1837 after returning from his voyage on the HMS Beagle. The library said they were worth millions of pounds.

In one book, he drew a diagram showing several possibilities for the evolution of a species and later published a more developed illustration in his 1859 book On the Origin of Species.

The University of Cambridge’s vast library first listed the notebooks as missing in 2001 after they were moved out of the Special Collections Strong Rooms for photography to be carried out there.

010 darwin books 1Close-up of Darwin’s iconic ‘Tree of Life’ sketch. (Charles Darwin/University of Cambridge)

They were long believed to have been incorrectly filed within the building, which contains around 10 million books, maps and manuscripts and has one of the world’s most significant Darwin archives.

However a major search this year – the largest in the library’s history – failed to turn up the notebooks.

“Curators have concluded the notebooks… have likely been stolen,” the library said in a statement.

It said it had informed local police and the books had been listed on Interpol’s database of stolen artworks, called Psyche.

 

The University Librarian, Jessica Gardner, released a video statement appealing to the public to help.

“It is deeply regretful to me that these notebooks remain missing despite numerous wide-scale searches over the last 20 years,” she said, adding that the library has since massively improved its security systems.

The librarian suggested that former or current library staff, those working in the book trade or researchers could have information.

“I would ask anyone who thinks they know of the notebooks’ whereabouts to get in touch. Please help,” she said.

The appeal was launched on November 24, known as Evolution Day since it marks the date of the publication of On the Origin of Species.

© Agence France-Presse

 



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