Ancient Triassic woodlouse discovery in Dutch Winterswijk


Winterswijk quarry with reconstruction drawing of Gelrincola winterswijkensis.  © Photo: Herman Winkelhorst, drawing by Erik-Jan Bosch (Naturalis Biodiversity Center)

Gelrincola winterswijkensis, A: Light microscope photo. B: Fluorescence microscope photo. C: Interpretative drawing. © Mario Schädel & prof. dr. Joachim Haug, Bulletin of Geosciences

Translated from Utrecht University in the Netherlands today:

Oldest woodlouse in the Netherlands discovered in Winterswijk quarry

A fossil woodlouse from the Triassic age, aged between 247 and 242 million years, has been discovered in the Winterswijk quarry. Never before has such an old woodlouse fossil been found in the Netherlands. It also turns out to be a new species. The find is extra special because fossil woodlice are extremely rare: until recently only nine species from the Triassic were known worldwide. The special fossil can be admired from 8 June on in Naturalis Biodiversity Center.

Woodlice do not only live in dark places or under stones: about half of all woodlouse species live in the sea. This in itself is not remarkable since woodlice are closely related to crabs and lobsters. The Winterswijk woodlouse also lived in the sea. The researchers named the new species Gelrincola winterswijkensis after the fossil site.

Gelrincola means ‘inhabitant of Gelderland province’.

The first woodlice appeared about 300 million years ago, during the Carboniferous. There are not many remains as ancient as Gelrincola winterswijkensis. Only ten species of woodlice are known from before the Triassic. More woodlice species are known from the eras after the Triassic. Today, more than ten thousand species of these crustaceans live.

The Winterswijk animal originates from the middle Triassic, a period of 247 to 242 million years ago. Back then Winterswijk was located on the edge of a large inland sea, the so-called Muschelkalk Sea. Along the coast of this Muschelkalk Sea there were extensive tidal plains where many remains of animals have been preserved in the lime mud. In Winterswijk you will find fossils from the sea as well as remains of animals that lived on land.

This yields a wide variety of fossils, including marine reptiles (such as Nothosaurus), fish, seashells, snails, ammonites, lobsters, a horseshoe crab, plant remains, pollen grains, footprints of terrestrial reptiles, and even fossil insects. So now a marine woodlouse can be added to this fossil biodiversity. This creates an increasingly complete picture of the ecosystem of the time. …

In our country, rocks from that interesting period only occur in the Winterswijk quarry.

This summer Naturalis Biodiversity Center and Utrecht University will continue to search for fossils there. A new visitors centre will be built next to the quarry, where the most important fossils from the quarry will be exhibited.

European and American lobsters crossbreeding, new research


This 2016 video from Britain is about European lobsters.

From the University of Exeter in England:

New test identifies lobster hybrids

May 11, 2020

Scientists have developed a test that can identify hybrids resulting from crossbreeding between European and American lobsters.

The Klu Klux Klan in the USA will consider these lobsters ‘communists’. As they claim that ‘race mixing’ is ‘communism’. As these picture show. They also show that Donald Trump’s anti-coronavirus health ‘Flu Klux Klan‘ consider social distancing ‘communist.’

American lobsters have occasionally escaped or been released into European waters after being imported for the seafood market.

Experts have long feared they could threaten European lobsters by introducing disease or establishing as an invasive species.

Hybridisation — when a “pure” species is threatened at a genetic level via interbreeding with a different but related species — had been less of a concern because lab studies suggested European and American lobsters were reluctant to mate.

However, when an American lobster female was found bearing eggs in a fjord in Sweden, University of Exeter researchers tested the offspring and found they were “clearly distinct” from both European and American lobsters.

“We had just developed a genetic test for seafood traceability that could separate any American lobsters mislabelled as more expensive European equivalents once they’ve been cooked and shell colouration is no longer a useful indicator of the species,” said Dr Charlie Ellis, of the University of Exeter.

“What we found when we tested these offspring is that they came out exactly in the middle of this separation — half American and half European — so these lobsters were hybrids.”

This has potentially concerning implications for the lobster industry and conservation efforts, and Dr Ellis says further research is required to assess the extent of the threat.

“Until recently, it was thought that American and European lobsters would avoid crossbreeding, but this introduced American female has mated with a native European male, probably because she was unable to find an American male,” he said.

“We now need to check whether any mature adult hybrids are fertile, because if they are then they have the ability to spread these unwanted American genes far and wide across our native lobster stocks.”

Working with collaborators from the University of Gothenburg who originally found the hybrid egg clutch, the researchers say their study, published in the journal Scientific Reports, highlights the vital use of genetics to distinguish hybrid lobsters which might look almost identical to a pure strain.

“It is particularly concerning that we seem to have found American lobster genes in one of our lobster reserves,” said Linda Svanberg of the Gothenburg team.

“The better news is we now have this genetic tool to test lobsters or their eggs for hybridisation,” added Dr Jamie Stevens, leader of the research which was funded by an EU grant through the Agritech Cornwall scheme, “so we can use it track the spread of these ‘alien’ genes to assess how big a threat this presents to our native lobster species.”

The team advise that, for a range of conservation reasons including potential contact with American lobsters, it is important that the general public never release a marketed lobster back into the wild, even our native species.

Dr Tom Jenkins said: “Although we appreciate that all animal-lovers have concern for the fate of individual animals, in this case the rescue of one animal might endanger the health of the entire wild population, so once a lobster has entered the seafood supply chain that’s where it should stay.”

How barnacles survive, video


This 22 April 2020 video from the USA says about itself:

How do barnacles survive environmental changes? Long-term work by a Brown University research team, with funding from the National Science Foundation, has confirmed that a central metabolic protein Mpi and the gene encoding the protein is what helps the barnacle survive extreme environmental changes.

Different versions of the Mpi enzyme are present at different levels, depending on where the barnacles have settled in the rocky shoreline. One form performs well under high stress, like on a hot day at low tide; the other form does better under low stress. This allows barnacles to survive and prosper in fluctuating extremes and has prepared them for success in an ever-changing environment.

Miocene fossil crab discovery in New Zealand


This 8 April 2020 video says about itself:

Man finds 12-million-year-old fossil, then spends 15 hours to expose crab hidden in stone

This timelapse footage shows an amateur palaeontologist uncovering an ancient crab fossil that he says is “12-million-years-old.”

The fossil, found on a beach in Christchurch, is encased in rock and Morne (Mamlambo on YouTube) carefully picks it away revealing the crab’s claws and shell.

Morne told Newsflare: “I found a fossil crab on a beach in New Zealand and then used an air scribe to remove the rock to show the fossil crab. It took about 10 hours and I made a timelapse of it.

“It [the fossil] is dated by the age of the rock it is found in, Miocene era in this case. The rock layers have been dated by some geologists using a variety of techniques, I use that information to date it. It isn’t very specific, rather a range.

“The species is a Tumidocarcinus giganteus. Found in New Zealand.”

How mantis shrimp find their way home


This 29 May 2019 video says about itself:

Mantis Shrimp Packs a Punch | Predator in Paradise

Armed with the most sophisticated vision and fastest strike of any predator on Earth, the mantis shrimp is an unexpected threat.

From the University of Maryland Baltimore County in the USA:

How do mantis shrimp find their way home?

April 9, 2020

Summary: New research indicates mantis shrimp use path integration to find their way back to their burrows after leaving to seek food or mates. That means they can track their distance and direction from their starting point. A series of creative experiments revealed that to do that, they rely on a hierarchy of cues from the sun, polarized light patterns, and their internal senses.

Mantis shrimps have earned fame for their powerful punching limbs, incredibly unusual eyes, and vivid exoskeletons. And, it turns out, they’re also really good at finding their way home. Through a series of painstaking experiments with these often-uncooperative creatures, Rickesh Patel has produced new findings on mantis shrimp navigation, published this week in Current Biology.

Patel, a Ph.D. candidate in biological sciences at UMBC, found that the species of mantis shrimp he investigated relies on the sun, patterns in polarized light, and internal cues — in that order — to navigate directly back to their non-descript burrows. These straight-line returns often follow forays that meander and zig-zag as the shrimp looks for a meal or a mate. The ability to get home quickly comes in handy when seeking shelter in the presence of predators, or a perceived one, as Patel noted on his first research fieldwork expedition.

After his first year at UMBC, Patel traveled with Tom Cronin’s lab to Lizard Island in the Great Barrier Reef to collect mantis shrimp for study. “As soon as they notice you, they’ll turn around and zip straight to some sort of shelter,” Patel says. Like a true scientist, “That got me wondering how they go about finding their way home.”

A crucial starting point

Scientists have written a great deal on navigation in other species — primarily bees, ants, and mice — but Patel’s is the first work on navigation in mantis shrimp.

First, Patel had to find a behavior he could work with to test ideas about how mantis shrimp navigate. So he created a small arena with an artificial shrimp burrow buried in sand. He placed the shrimp in the arena, and to his delight, the mantis shrimp was happy to occupy the small section of PVC pipe. Then he placed a piece of food at a distance from the burrow. He watched as the shrimp left its burrow, meandered until it found the food, and then returned to its burrow in a fairly straight line.

From those initial observations, Patel hypothesized that mantis shrimps use a process called path integration to find their way home. In other words, they are somehow able to track both their distance and direction from their burrow.

“That was probably the most exciting part of the experiments for me, because I knew I had a really robust behavior that I could work with,” Patel says. “Everything I did really extended from that initial point.”

Sunshine surprise

After that first discovery, the challenging work began, to figure out what cues the animals were using to determine the path home.

Patel built eight much larger arenas, each about 1.5 meters in diameter, to run his experiments. The first question he asked was whether the shrimp were using internal or external cues to go home.

To test that, Patel created a setup that rotated the animal 180 degrees as it retrieved the food. If the shrimp was using external cues to remember its distance and direction from home, it would still head in the right direction. If it was using internal cues, based on the orientation of its own body, it would head in the opposite direction. In the first round of trials, the animals consistently headed in the exact opposite direction.

“That was really cool, but it didn’t make a lot of sense,” Patel says, “because an internal compass is going to be a lot less accurate than something that is tied to the environment.” Then it hit him: “We just happened to have a really overcast week when I did these experiments, so I waited until we had a clear day, and then every time, they went right back home.”

Putting together the puzzle

Patel realized that his experiment perfectly demonstrated the hierarchy of cues used by the animals. They used external cues first, but when those weren’t available, they used internal cues.

That was the beginning of a long series of creative experiments that further teased out how these animals navigate. When Patel used a mirror to trick the animals into thinking the sun was coming from the opposite direction, they went the wrong way. This indicated they use the sun as a primary cue. When it was cloudy but not totally dark, they used polarization patterns in light, which are still detectable when it’s overcast. And when the sky was completely covered, they reverted to their internal navigation system.

A varied skillset

For Patel, creating the experimental arenas — essentially, the shrimp obstacle course — was almost as fun as getting the results. “That’s something I really enjoy — building things, creating things,” he shares. Patel studied art and biology as an undergraduate at California State University, Long Beach. “I think those skills lent me a hand in designing my experiments.”

Other skills Patel needed were patience and perseverance. “The animals will only behave maybe once a day, so if you scare the animal, you’ve lost that day,” he says.

For example, one of the experiments involved putting the animals on a track that pulled them to a new position, and seeing where they headed from there. “If the track is too jerky or goes too fast, they get scared and just don’t behave,” Patel says. “So I had to design the experiment so that it was so gentle they didn’t realize they were being moved.”

New questions

All of Patel’s patience has paid off with new findings that open up an array of future questions to answer. While path integration is well-documented in other species, mantis shrimp are the first to demonstrate the technique underwater. Looking up at the sky through water is a very different view than doing so through air, so Patel is curious how the animals’ process is different from other species.

Patel is also ultimately interested in the neural basis of navigation behavior, but “before you can investigate what’s happening in the brain, you have to understand what the animal’s doing,” he says. “So that’s why I really focused on the behavior work, to figure out what the animal is doing and what kind of stimuli are appropriate to show the animal that we can use to investigate its neurology.”

So far, other work has demonstrated that a brain region called the central complex has uncanny similarities between insects and mantis shrimps. This is especially interesting considering how far apart bees and shrimp are on the tree of life. The central complex is known to contribute to navigation in bees, so Patel is intrigued to learn more about its function in mantis shrimp. Alice Chou, another graduate student in the Cronin lab, is also investigating the brain structures of mantis shrimp.

Cuban land crabs’ mass migration, videos


This 20 March 2020 video, recorded in Cuba, says about itself:

Swarm of Crab Mothers Cross Traffic to Lay Thousands of Eggs

An army of red land crabs migrates miles as some mothers prepare to lay up to 80,000 eggs apiece.

I saw migrating crabs in Cuba.

This May 2017 video says about itself:

Cuba: Crabs invade Bay of Pigs showing US how it’s done

Millions of crabs have invaded Cuba’s Bay of Pigs (Playa Giron), as shown by footage filmed on Wednesday.

The red, yellow and black crabs are undertaking their annual spring migration from the forest to the sea, where they aim to release their eggs.

Christmas Island crab steals expensive camera


This video says about itself:

Thursday, 12 March 2020

Robber crab‘ steals expensive research equipment

Western Sydney University Doctor of Philosophy candidate Annabel Dorrestein had been using the expensive camera as part of her research project on Christmas Island.

Dutch Ms Dorrestein used the camera for research on Christmas Island flying-foxes (Pteropus melanotus natalis).

Shrimps’, insects’ brains are similar


This 9 October 2017 video says about itself:

Insect like Brain Region Found in Crustacean Brain

Mushroom bodies are the iconic learning and memory centers of insects. No previously described crustacean possesses a mushroom body as defined by strict morphological criteria although crustacean centers called hemiellipsoid bodies, which serve functions in sensory integration, have been viewed as evolutionarily convergent with mushroom bodies. Here, using key identifiers to characterize neural arrangements, we demonstrate insect-like mushroom bodies in stomatopod crustaceans (mantis shrimps).

More than any other crustacean taxon, mantis shrimps display sophisticated behaviors relating to predation, spatial memory, and visual recognition comparable to those of insects. However, neuroanatomy-based cladistics suggesting close phylogenetic proximity of insects and stomatopod crustaceans conflicts with genomic evidence showing hexapods closely related to simple crustaceans called remipedes. We discuss whether corresponding anatomical phenotypes described here reflect the cerebral morphology of a common ancestor of Pancrustacea or an extraordinary example of convergent evolution.

From the University of Arizona in the USA:

The brains of shrimps and insects are more alike than we thought

March 3, 2020

New research shows that crustaceans such as shrimps, lobsters and crabs have more in common with their insect relatives than previously thought — when it comes to the structure of their brains.

Both insects and crustaceans possess mushroom-shaped brain structures known in insects to be required for learning, memory and possibly negotiating complex, three-dimensional environments, according to the study, led by University of Arizona neuroscientist Nicholas Strausfeld.

The research, published in the open-access journal eLife, challenges a widely held belief in the scientific community that these brain structures — called “mushroom bodies” — are conspicuously absent from crustacean brains.

In 2017, Strausfeld’s team reported a detailed analysis of mushroom bodies discovered in the brain of the mantis shrimp, Squilla mantis. In the current paper, the group provides evidence that neuro-anatomical features that define mushroom bodies — at one time thought to be an evolutionary feature proprietary to insects — are present across crustaceans, a group that includes more than 50,000 species.

Crustaceans and insects are known to descend from a common ancestor that lived about a half billion years ago and has long been extinct.

“The mushroom body is an incredibly ancient, fundamental brain structure,” said Strausfeld, Regents Professor of neuroscience and director of the University of Arizona’s Center for Insect Science. “When you look across the arthropods as a group, it’s everywhere.”

In addition to insects and crustaceans, other arthropods include arachnids, such as scorpions and spiders, and myriapods, such as millipedes and centipedes.

Characterized by their external skeletons and jointed appendages, arthropods make up the most species-rich group of animals known, populating almost every conceivable habitat. About 480 million years ago, the arthropod family tree split, with one lineage producing the arachnids and another the mandibulates. The second group split again to provide the lineage leading to modern crustaceans, including shrimps and lobsters, and six-legged creatures, including insects — the most diverse group of arthropods living today.

Decades of research have untangled arthropods’ evolutionary relationships using morphological, molecular and genetic data, as well as evidence from the structure of their brains.

Mushroom bodies in the brain have been shown to be the central processing units where sensory input converges. Vision, smell, taste and touch all are integrated here, as studies on honeybees have shown. Arranged in pairs, each mushroom body consists of a column-like portion, called the lobe, capped by a dome-like structure, called the calyx, where neurons that relay information sent from the animal’s sensory organs converge. This information is passed to neurons that supply thousands of intersecting nerve fibers in the lobes that are essential for computing and storing memories.

Recent research by other scientists has also shown that those circuits interact with other brain centers in strengthening or reducing the importance of a recollection as the animal gathers experiences from its environment.

“The mushroom bodies contain networks where interesting associations are being made that give rise to memory,” Strausfeld said. “It’s how the animal makes sense of its environment.”

A more evolutionarily “modern” group of crustaceans called Reptantia, which includes many lobsters and crabs, do indeed appear to have brain centers that don’t look at all like the insect mushroom body. This, the authors suggest, helped create the misconception crustaceans lack the structures altogether.

Brain analysis of crustaceans has revealed that while the mushroom bodies found in crustaceans appear more diverse than those of insects, their defining neuroanatomical and molecular elements are all there.

Using crustacean brain samples, the researchers applied tagged antibodies that act like probes, homing in on and highlighting proteins that have been shown to be essential for learning and memory in fruit flies. Sensitive tissue-staining techniques further enabled visualization of mushroom bodies’ intricate architecture.

“We know of several proteins that are necessary for the establishment of learning and memory in fruit flies,” Strausfeld said, “and if you use antibodies that detect those proteins across insect species, the mushroom bodies light up every time.”

Using this method revealed that the same proteins are not unique to insects; they show up in the brains of other arthropods, including centipedes, millipedes and some arachnids. Even vertebrates, including humans, have them in a brain structure called the hippocampus, a known center for memory and learning.

“Corresponding brain centers — the mushroom body in arthropods, marine worms, flatworms and, possibly, the hippocampus of vertebrates — appear to have a very ancient origin in the evolution of animal life,” Strausfeld said.

So why do the most commonly studied crustaceans have mushroom bodies that can appear so drastically different from their insect counterparts? Strausfeld and his co-authors have a theory: Crustacean species that inhabit environments that demand knowledge about elaborate, three-dimensional areas are precisely the ones whose mushroom bodies most closely resemble those in insects, a group that has also mastered the three-dimensional world by evolving to fly.

“We don’t think that’s a coincidence,” Strausfeld says. “We propose that the complexity of inhabiting a three-dimensional world may demand special neural networks that allow a sophisticated level of cognition for negotiating that space in three dimensions.”

Lobsters and crabs, on the other hand, spend their lives confined mostly to the seafloor, which may explain why they’ve historically been said to lack mushroom bodies.

“At the risk of offending colleagues who are partial to crabs and lobsters: I view many of these as flat-world inhabitants,” Strausfeld says. “Future studies will be able to tell us which are smarter: the reef-dwelling mantis shrimp, a top predator, or the reclusive lobster.”

Strausfeld co-authored the paper with two of his former students — Gabriella Wolff, now a post-doctoral fellow at the University of Washington, and Marcel Sayre, now a doctoral student at Lund University in Sweden. They hope that the study of mushroom bodies will further help in resolving how brains may have evolved and what environmental conditions shaped that process.

This research moves us closer to answering the ultimate question,” Strausfeld says. “We want to know: What was the earliest brain like?”