Ancient worms, new study


This 22 January 2018 video is called A 508 million year old worm sheds light on an evolutionary enigma.

From the Royal Ontario Museum in Canada:

Kicking an old can of worms — the origin of the head in annelids

New 508-million-year-old bristle worm species from British Columbia’s Burgess Shale wiggles into evolutionary history

January 22, 2018

Summary: Researchers have described an exceptionally well-preserved new fossil species of bristle worm called Kootenayscolex barbarensis. Discovered from the 508-million-year-old Marble Canyon fossil site in the Burgess Shale in Kootenay National Park, the new species helps rewrite our understanding of the origin of the head in annelids, a highly diverse group of animals which includes today’s leeches and earthworms.

Researchers at the Royal Ontario Museum and the University of Toronto have described an exceptionally well-preserved new fossil species of bristle worm called Kootenayscolex barbarensis. Discovered from the 508-million-year-old Marble Canyon fossil site in the Burgess Shale in Kootenay National Park, British Columbia, the new species helps rewrite our understanding of the origin of the head in annelids, a highly diverse group of animals which includes today’s leeches and earthworms. This research was published today in the journal Current Biology in the article “A New Burgess Shale Polychaete and the Origin of the Annelid Head Revisited.”

“Annelids are a hugely diverse group of animals in both their anatomies and lifestyles,” said Karma Nanglu, a University of Toronto PhD candidate, and a researcher at the Royal Ontario Museum, as well as the study’s lead author. “While this diversity makes them ecologically important and an evolutionarily interesting group to study, it also makes it difficult to piece together what the ancestral annelid may have looked like.”

Annelids are found in nearly all marine environments from hydrothermal vents to coral reefs to the open ocean, and also include more evolutionary derived species living on land today. Although quite abundant in modern environments, their early evolutionary history, in particular the origin of their heads, is confounded by a relatively poor fossil record, with few species described from well-preserved body fossils near the evolutionary origins of the group.

Co-author Dr. Jean-Bernard Caron, Senior Curator of Invertebrate Palaeontology at the Royal Ontario Museum, Associate Professor in the departments of Ecology & Evolutionary Biology and Earth Sciences at U of T, and Nanglu’s PhD supervisor, said: “While isolated pieces of annelid jaws and some annelid tubes are well known in the fossil record, preservation of their soft tissues is exceedingly rare. You need to look to truly exceptional fossil deposits like those found in the 508-million-year-old Burgess Shale locality in British Columbia to find well preserved body fossils. Even then, they’re quite uncommon and many of the currently described species there are still poorly understood.”

One key feature of the new Burgess Shale worm Kootenayscolex barbarensis is the presence of hair-sized bristles called chaetae on the head which led Nanglu and Caron to propose a new hypothesis regarding the early evolution of the head in annelids. “Like other bristle worms, Kootenayscolex possesses paired bundles of hair-sized bristles spread along the body; this is in fact one of the diagnostic features of this group of animals”, Nanglu added. “However, unlike any living forms, these bristles were also partially covering the head, more specifically surrounding the mouth. This new fossil species seems to suggest that the annelid head evolved from posterior body segments which had pair bundles of bristles, a hypothesis supported by the developmental biology of many modern annelid species.”

The Cambrian Period (541-485 million years ago) represents the first time that most animal groups appear in the fossil record, however, many species often possessed morphologies that were very unlike their modern relatives. “Coupling new fossil discoveries, such as Kootenayscolex, with a deeper understanding of developmental processes presents a powerful tool for investigating these unique morphologies and, ultimately, the origin of modern animal diversity”, added Dr. Caron.

The description of Kootenayscolex is one of many new discoveries from the Burgess Shale site called Marble Canyon (Kootenay National Park) which are changing the way we think about the evolution of a wide array of animal groups. Dr. Caron led the ROM research team that uncovered this new locality in 2012, 40 km southeast of the original Burgess Shale site (Yoho National Park) in the Canadian Rockies. This new bristle worm is not only the most abundant species of annelid throughout the entire fossil record with more than 500 specimens recovered, but also the best preserved so far. “Some specimens preserved remnants of internal tissues, including possible nervous tissues, which is the first time we see evidence of such delicate features in a fossil annelid. This exceptional preservation opens a new chapter in the study of these ancient worms” added Caron.

“508 million years ago, the Marble Canyon would have been teeming with annelids,” said Nanglu. “The fine anatomical details preserved in Kootenayscolex allow us to infer not only its evolutionary position, but also its lifestyle. Sediment preserved inside their guts suggest that, much as their relatives do in modern ecosystems, these worms served an important role in the food chain by recycling organic material from the sediment back to other animals that preyed on them.”

The new annelid’s species name, barbarensis, was chosen to honour Barbara Polk Milstein, who is a Royal Ontario Museum volunteer and longtime supporter of Burgess Shale research. Kootenayscolex barbarensis is brought to life by ROM visual artist and scientific illustrator Danielle Dufault.

A dying worm experiences rigor mortis early in the death process, rather than after the main event as it is for humans, according to a new study: here.

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Can earthworms survive on Mars?


This 6 October 2017 video from the Netherlands is called Earthworm in Mars soil simulant.

From Wageningen University & Research in the Netherlands:

Earthworms can reproduce in Mars soil simulant

November 27, 2017

Two young worms are the first offspring in a Mars soil experiment at Wageningen University & Research. Biologist Wieger Wamelink found them in a Mars soil simulant that he obtained from NASA. At the start he only added adult worms. The experiments are crucial in the study that aims to determine whether people can keep themselves alive at the red planet by growing their own crops on Mars soils.

To feed future humans on Mars a sustainable closed agricultural ecosystem is a necessity. Worms will play a crucial role in this system as they break down and recycle dead organic matter. The poop and pee of the (human) Martian will also have to be used to fertilise the soil, but for practical and safety reasons we are presently using pig slurry. We have since been observing the growth of rucola (rocket) in Mars soil simulant provided by NASA to which worms and slurry have been added. ‘Clearly the manure stimulated growth, especially in the Mars soil simulant, and we saw that the worms were active. However, the best surprise came at the end of the experiment when we found two young worms in the Mars soil simulant’, said Wieger Wamelink of Wageningen University & Research.

‘The positive effect of adding manure was not unexpected’, added Wamelink, ‘but we were surprised that it makes Mars soil simulant outperform Earth silver sand’. We added organic matter from earlier experiments to both sands. We added the manure to a sample of the pots and then, after germination of the rucola, we added the worms. We therefore ended up with pots with all possible combinations with the exception of organic matter which was added to all of the pots.

Worms are very important for a healthy soil, not only on Earth but also in future indoor gardens on Mars or the moon. They thrive on dead organic matter such as old plant remains, which they eat, chew and mix with soil before they excrete it. This poo still contains organic matter that is broken down further by bacteria, thus releasing nutrients such as nitrogen, phosphorus and potassium for use by the plants. By digging burrows the worms also aerate and improve the structure of the soil, making watering the plants more effective. The latter proved to be very important in earlier experiments where water would not easily penetrate the soil. Wamelink confirmed that: ‘the application of worms will solve this problem’.

To feed the future humans living on Mars or the moon the project Food for Mars and Moon aims to set up a sustainable agricultural system. It is based on the presence of soils and water (in the form of ice) on both Mars and the moon, and for Earth-based research we are using soil simulants delivered by NASA. The simulants originate from a volcano in Hawaii (Mars) and a desert in Arizona (moon). The experiments started in 2013. Nowadays we are able to grow over a dozen crops, the only species that has resisted our efforts so far is spinach. However crops such as green beans, peas, radish, tomato, potato, rucola, carrot and garden cress all seem possible. The crops were analysed for heavy metals and also alkaloids to check their safety for human consumption. After passing these tests we organized a dinner based on the harvested crops for the people that supported our research via the crowdfunding campaign.

For the first time, researchers have seen life rebounding in the world’s driest [Atacama] desert, demonstrating that it could also be lurking in the soils of Mars: here.

Herring gull and worms video


This 28 March 2017 video is about a herring gull trying to catch worms by trampling on the ground.

Cor Huijgens in the Netherlands made this video.

Three new flatworm species discovered in Brazil


This video says about itself:

Huge flatworm (Platyhelminthes) on the move

16 August 2009

We discovered this flatworm on one of our nightly walks in the jungle of Itatiaia National Park in Brazil.

From Phys.org:

Hidden diversity: 3 new species of land flatworms from the Brazilian Araucaria forest

January 9, 2017

A huge invertebrate diversity is hidden on the forest floor in areas of the Araucaria moist forest, Brazil. Land flatworms constitute a numerous group among these invertebrates occurring in the Neotropical region. Flatworms are considered to be top predators within the soil ecosystem, preying on other invertebrates.

The Araucaria moist forest is part of the Brazilian Atlantic Rain Forest and is considered a hotspot of land flatworm diversity, harboring many yet undescribed species. A study recently published in the open access journal ZooKeys describes three new species from areas covered by Araucaria moist forest in South Brazil, which belong to the Neotropical genus Cratera.

Land flatworms lack a water retention mechanism and have a low tolerance to intense changes in temperature and humidity. Their low vagility leads to the existence of a high number of endemic species. Thus, they are considered good bioindicators of the degree of impact on their habitat.

The new species are named after characteristics of their color pattern and are probably endemic for the study areas. Besides differing from each other, as well as from other species of the genus, by their characteristic color pattern, they also show other distinguishing features in the reproductive system. The study provides an identification key to the species of the genus.

The work was conducted by the south Brazilian research group on triclads, led by Dr. Ana Leal-Zanchet, of the Universidade do Vale do Rio dos Sinos (UNISINOS), in southern Brazil. The study was supported by the Brazilian Research Council (CNPq).

Flatworms in the Netherlands: here.

Flatworms that spent five weeks aboard the International Space Station are helping researchers scientists study how an absence of normal gravity and geomagnetic fields can have anatomical, behavioral, and bacteriological consequences, according to a paper. The research has implications for human and animal space travelers and for regenerative and bioengineering science: here.

Acorn worms, new research


This video says about itself:

29 November 2016

What if humans could regrow an amputated arm or leg, or completely restore nervous system function after a spinal cord injury?

A new study of one of our closest invertebrate relatives, the acorn worm, reveals that this feat might one day be possible. Acorn worms burrow in the sand around coral reefs, but their ancestral relationship to chordates means they have a genetic makeup and body plan surprisingly similar to ours.

Read more here.

From Science News in the USA:

These acorn worms have a head for swimming

Putting off trunk development may make catching prey easier, researchers say

By Emily DeMarco

10:00am, January 3, 2017

Certain marine worms spend their larval phase as little more than a tiny, transparent “swimming head.” A new study explores the genes involved in that headfirst approach to life.

A mud flat in Morro Bay, Calif., is the only known place where this one species of acorn worm, Schizocardium californicum, is found. After digging up the creatures, Paul Gonzalez, an evolutionary developmental biologist at Stanford University, raised hordes of the larvae at Stanford’s Hopkins Marine Station in Pacific Grove, Calif.

Because a larva and an adult worm look so different, scientists wondered if the same genes and molecular machinery were involved in both phases of development. To find out, Gonzalez and colleagues analyzed the worm’s genetic blueprint during each phase, they report online December 8 in Current Biology.

Genes linked to trunk development were switched off during the larval phase until just before metamorphosis. Instead, most of the genes switched on were associated with head development, Gonzalez says.

The larvae hatch from eggs laid on the mud. When tides flood the area, the squishy, gel-filled animals use hairlike cilia to swim upwards to devour bits of algae. “They’re feeding machines,” Gonzalez says. He speculates that being balloon-shaped noggins, rather than wriggling noodles, may help the organisms float and feed more efficiently.

After about two months of gorging at the algae buffet, the larvae, which grow to roughly 2 millimeters across, transform and sink back into the muck. There, they eventually grow a body that can stretch up to about 40 centimeters.

Kestrel eats worm, video


In this 30 January 2016 video from Biesbosch national park in the Netherlands, a female kestrel eats a worm.

More on this is here.

Giant worms discovery on Scottish island


This video from Scotland says about itself:

Giant worms the size of SNAKES are discovered by scientists on abandoned Scottish island

18 January 2016

Researchers says the creatures are three to four times bigger than the average worm and ‘slightly spooky’.

From Wildlife Extra:

Giant worms discovered on remote Scottish island

It sounds like the stuff of nightmares – giant earthworms that, if left alone, keep growing and growing to the size of a baby snake. But this is no bad dream – scientists working on the Isle of Rum, off the coast of Scotland, have found the biggest specimens ever seen in the UK, more than three times the length and weight of a normal worm.

The exceptionally large invertebrates measure up 40 cm (1.3 ft) long, having blossomed due to rich soil and a lack of predators. They’re similar in size to a newly-hatched adder.

In an interview on the BBC Radio 4 Today programme, Dr Kevin Butt, lead researcher on the earthworm study, carried out by the University of Central Lancashire, said: “These things weigh about twelve and a half grams – but the normal size for these things is about four to five grams.”

The worms, Latin name Lumbricus terrestris, were found at Papadil, an abandoned settlement on Rum, which is home to a tiny population of around 30 people.

“When these things came out of their burrows they were like small snakes,” he said.

However, far from being the stuff of nightmares, Dr Butt told the Telegraph the existence of the worms was “a delight” to discover as they are crucial to the ecosystem, and help lessen the risk of flooding.

“Without their activities we’d be a lot worse off. They’re just as important as bees are in pollinating plants. They help aerate the soil and drain away water and stop surface erosion,” he explained.

Dr Butt believes the Rum worms are bigger than average due to their remote, undisturbed location, with good quality soil. Rum also lacks predators such as badgers, moles, hedgehogs and foxes which would usually gobble the worms before they had chance to grow into monsters. Unlike most animals, which stop growing once they reach an adult size, earthworms keep on growing if left alone.

“These things have just have been left and have grown bigger and bigger,” explained Dr Butt, who has been studying earthworms for around 30 years.

Asked if an enthusiastic schoolboy might be able to achieve a similarly giant specimen by looking after it at home, he confirmed this is possible.

“In the laboratory we can keep them and feed them well and in a matter of a couple of years you can grow them to 15, even 20 grams,” he said.

However, those spooked by the idea of giant worms have little to fear if they visit Rum.

“If they feel footsteps they will just go down deeper into the earth. They’re not going to jump out and grab people,” he said.

News of the Papadil worms is contained in a paper recently published in The Glasgow Naturalist journal.

From giant rats to dwarf elephants, island living changes mammals. Island mammals evolve differently from those on the mainland – which can be clearly seen in fossils such as the giant ‘terror shrew’ or dwarf hippopotamus: here.