Leopard slug video


This 17 August 2017 video is about a leopard slug.

Marc Canton made this video near Arnhem city in Gelderland province in the Netherlands.

Dinosaur age damselfly named after David Attenborough


This video says about itself:

15 August 2017

Damselfly thought to be 100 MILLION years old named after Sir David Attenborough

TV naturalist Sir David Attenborough was last night said to be delighted after a prehistoric insect was named in his honour. Prof. Jarzembowski said: “Dragonflies in amber are extremely rare and the recent discoveries by my Chinese colleagues are a new window on the past. “It is tradition in taxonomy – the naming of a new species – to contact the person concerned. “Sir David was delighted because he is not only interested in the story of amber, but also a president of the British Dragonfly Society.”

Lead author Daran Zheng from the Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, commented: “Mesosticta davidattenboroughi is quite unique because we have uncovered a new species.” The naming of the species was revealed in the Journal of Systematic Palaeontology.

Mesosticta davidattenboroughi is just the latest species to be named after Sir David whose wildlife documentaries have enchanted the world. Others include a carnivorous plant, a butterfly, a tiny spider, a Peruvian frog and a Namibian lizard. Among the prehistoric species named after him are a Mesozoic reptile, a fossilised armoured fish and a 430 million-year-old crustacean.

From ScienceDaily:

David Attenborough gains new species namesake

August 16, 2017

A new species of damselfly from the Cretaceous period has been named after the iconic naturalist and TV presenter Sir David Attenborough.

The new discovery, described in detail in the Journal of Systematic Palaeontology, was made in the Hukawng Valley of Kachin Province in Myanmar. The fossil was found in a piece of mid-Cretaceous Burmese amber. The full scientific name for the new species, belonging to a group more commonly known as shadowdamsels, is Mesosticta davidattenboroughi. Researchers decided to name the new species after David Attenborough because of his long-standing appreciation of dragonflies, and to celebrate his recent 90th birthday.

The fossil itself is extremely well preserved as it is encased in yellow transparent amber and includes a complete set of wings. With the aid of photo technology, researchers were able to digitally enhance and build a clear three-dimensional picture of the new species, showing that it differed from previously described fossils, notably in the shorter wing length.

Lead author Daran Zheng from the Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, commented, “Mesosticta davidattenboroughi is quite unique because we have uncovered a new species and it confirms the previous attribution of Mesosticta to the Platystictidae. It is the first fossil group of modern platystictid damselflies and documents the appearance of Platystictidae as early as mid-Cretaceous.”

The discovery of insect remains in amber is not uncommon, however this particular family of damselflies are much less frequently found and their fossil record is poor compared to many other families making the discovery especially unusual.

Mesosticta davidattenboroughi joins a long list of animals which have been named after Sir David Attenborough, including a weevil and fossil species of a plesiosaur and a fish.

This research was supported by the National Natural Science Foundation of China, Youth Innovation Promotion Association of the Chinese Academy of Sciences and the HKU Seed Funding Program for Basic Research.

See also here. And here.

Prehistoric spider journey from Africa to Australia?


This video from Australia says about itself:

2 August 2017

This spider floated 6,000 miles across the Indian Ocean millions of years ago.

By Sarah Zielinski, 9:00am, August 15, 2017:

These spiders crossed an ocean to get to Australia

If you look at a map of the world, it’s easy to think that the vast oceans would be effective barriers to the movement of land animals. And while an elephant can’t swim across the Pacific, it turns out that plenty of plants and animals — and even people — have unintentionally floated across oceans from one continent to another. Now comes evidence that tiny, sedentary trapdoor spiders made such a journey millions of years ago, taking them from Africa all the way across the Indian Ocean to Australia.

Moggridgea rainbowi spiders from Kangaroo Island, off the south coast of Australia, are known as trapdoor spiders because they build a silk-lined burrow in the ground with a secure-fitting lid, notes Sophie Harrison of the University of Adelaide in Australia. The burrow and trapdoor provides the spiders with shelter and protection as well as a means for capturing prey. And it means that the spiders don’t really need to travel farther than a few meters over the course of a lifetime.

There was evidence, though, that the ancestors of these Australian spiders might have traveled millions of meters to get to Australia — from Africa. That isn’t as odd as it might seem, since Australia used to be connected to other continents long ago in the supercontinent Gondwana. And humans have been known to transport species all over the planet. But there’s a third option, too: The spiders might have floated their way across an ocean.

To figure out which story is most likely true, Harrison and her colleagues looked at the spider’s genes. They turned to six genes that have been well-studied by spider biologists seeking to understand relationships between species. The researchers looked at those genes in seven M. rainbowi specimens from Kangaroo Island, five species of Moggridgea spiders from South Africa and seven species of southwestern Australia spiders from the closely related genus Bertmainius.

Using that data, the researchers built a spider family tree that showed which species were most closely related and how long ago their most recent common ancestor lived. M. rainbowi was most closely related to the African Moggridgea spiders, the analysis revealed. And the species split off some 2 million to 16 million years ago, Harrison and her colleagues report August 2 in PLOS ONE.

The timing of the divergence was long after Gondwana split up. And it was long before either the ancestors of Australia’s aboriginal people or later Europeans showed up on the Australian continent. While it may be improbable that a colony of spiders survived a journey of 10,000 kilometers across the Indian Ocean, that is the most likely explanation for how the trapdoor spiders got to Kangaroo Island, the researchers conclude.

Such an ocean journey would not be unprecedented for spiders in this genus, Harrison and her colleagues note. There are three species of Moggridgea spiders that are known to live on islands off the shore of the African continent. Two live on islands that were once part of the mainland, and they may have diverged at the same time that their islands separated from Africa. But the third, M. nesiota, lives on the Comoros, which are volcanic islands. The spiders must have traveled across 340 kilometers of ocean to get there.

These types of spiders may be well-suited to ocean travel. If a large swatch of land washes into the sea, laden with arachnids, the spiders may be able to hide out in their nests for the journey. Plus, they don’t need a lot of food, can resist drowning and even “hold their breath” and survive on stored oxygen during periods of temporary flooding, the researchers note.

Brittle stars fossils discovery in Australia


This video says about itself:

13 August 2017

Australia was a different place 275 million years ago – wild storms surged through icy seas, and marine animals lived a tenuous existence. But brittle stars had a survival strategy.

From the University of Cambridge in England:

Meadow of dancing brittle stars shows evolution at work

August 14, 2017

Newly-described fossil shows how brittle stars evolved in response to pressure from predators, and how an ‘evolutionary hangover’ managed to escape them.

Researchers have described a new species of brittle star, which are closely related to starfish, and showed how these sea creatures evolved in response to the rise of shell-crushing predators during the late Palaeozoic Era. The results, reported in the Journal of Systematic Palaeontology, also suggest that brittle stars evolved new traits before the largest mass extinction event in Earth’s history, and not after, as was the case with many other forms of life.

A fossilised ‘meadow’ of dancing brittle stars — frozen in time in the very spot that they lived — was found in Western Australia and dates from 275 million years ago. It contains several remarkably preserved ‘archaic’ brittle stars, a newly-described genus and species called Teleosaster creasyi. They are the last known complete brittle stars of their kind, an evolutionary hangover pushed to the margins of the world’s oceans by the threat from predators.

The researchers, from the University of Cambridge, suggest that while other species of brittle stars evolved in response to predators such as early forms of rays and crabs, these archaic forms simply moved to where the predators weren’t — namely the seas around Australia, which during the Palaeozoic era was pushed up against Antarctica. In these cold, predator-free waters, the archaic forms were able to grow much larger, and lived at the same time as the modern forms of brittle star, which still exist today.

Brittle stars consist of a central disc and five whip-like appendages, which are used for locomotion. They first appear in the fossil record about 500 million years ago, in the Ordovician Period, and today there are about 2,100 different species, mostly found in the deep ocean.

Early brittle stars were just that: brittle. During the Palaeozoic Era, when early shell-crushing predators first appeared, brittle stars made for easy prey. At this point, a split in the evolutionary tree appears to have occurred: the archaic, clunky brittle stars moved south to polar waters, while the modern form first began to emerge in response to the threat from predators, and was able to continue to live in the warmer waters closer to the equator. Both forms existed at the same time, but in different parts of the ocean.

“The threat from predation is an under-appreciated driver of evolutionary change,” said study co-author Dr Kenneth McNamara of Cambridge’s Department of Earth Sciences. “As more predators began to appear, the brittle stars started to evolve more flexible bodies, which enabled them to either burrow into the sediment, or to move more rapidly to escape.”

About 250 million years ago, the greatest mass extinction in Earth’s history — the Permian-Triassic extinction event, or the “Great Dying” — occurred. More than 90% of marine species and 70% of terrestrial species went extinct, and as a result, most surviving species underwent major evolutionary changes as a result.

“Brittle stars appear to have bucked this trend, however,” said co-author Dr Aaron Hunter, a visiting postdoctoral researcher in the Department of Earth Sciences. “They seem to have evolved before the Great Dying, into a form which we still see today.”

Meadows of brittle stars and other invertebrates such as sea urchins and starfish can still be seen today in the seas around Antarctica. As was the case during the Palaeozoic, the threat from predators is fairly low, although the warming of the Antarctic seas due to climate change has been linked to the recent arrival of armies of king crabs, which represent a real threat to these star-filled meadows.

Butterflies in the USA


This video from the USA says about itself:

7 August 2017

Beautiful Clouded Sulfur Butterflies, Swallowtail Butterflies and other pollinators set to relaxing ambient music.