Dragonflies, other insects in city center


This video is called [Female] Green-eyed Hawker – Aeshna isoceles – Vroege glazenmaker / Schoten – Belgium / June 2015.

According to Leids Nieuwsblad weekly, 21 June 2018, green-eyed hawker dragonflies are among insect species seen in the Kruidentuin garden in Leiden city center. Others are hummingbird hawk-moth, European wool carder bee and hornet mimic hoverfly.

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New Sri Lankan spiders get Enid Blyton names


This video says about itself:

Science Bulletins: Seeking Spiders—Biodiversity on a Different Scale

4 October 2012

Recognizing the tiny species of any ecosystem is hugely important for defining its overall diversity. But miniscule forms of life are often invisible to conservation efforts because they have yet to be described in detail. Dr. Norman Platnick of the American Museum of Natural History is leading an important initiative to discover biodiversity on a smaller scale. Having devoted decades to the study of spiders, Dr. Platnick now leads a team of 45 investigators from 10 countries in the largest-ever research project on spiders, identifying members of the goblin spider family. This group of spiders is widely distributed but largely unknown, primarily due to their small size—at 1.2-3mm, they measure one-half to one-third the length of the average spider. This video follows Dr. Platnick’s team into the Ecuadorian jungle as they collect and identify scores of unrecognized goblin spiders, showing how little we know about the full breadth of global biodiversity.

From ScienceDaily:

Six new species of goblin spiders named after famous goblins and brownies

June 21, 2018

Summary: A remarkably high diversity of goblin spiders is reported from the Sri Lankan forests. Nine new species are described in a recent paper, where six are named after goblins and brownies from Enid Blyton‘s children’s books. There are now 45 goblin spider species belonging to 13 genera known to inhabit the island country.

Fictional characters originally ‘described’ by famous English children’s writer Enid Blyton have given their names to six new species of minute goblin spiders discovered in the diminishing forests of Sri Lanka.

The goblins Bom, Snooky and Tumpy and the brownies Chippy, Snippy and Tiggy made their way from the pages of: “The Goblins Looking-Glass” (1947), “Billy’s Little Boats” (1971) and “The Firework Goblins” (1971) to the scientific literature in a quest to shed light on the remarkable biodiversity of the island country of Sri Lanka, Indian Ocean.

As a result of their own adventure, which included sifting through the leaf litter of the local forests, scientists Prof. Suresh P. Benjamin and Ms. Sasanka Ranasinghe of the National Institute of Fundamental Studies, Sri Lanka, described a total of nine goblin spider species in six genera as new to science. Two of these genera are reported for the very first time from outside Australia.

Their paper is published in the open access journal Evolutionary Systematics.

With a total of 45 species in 13 genera, the goblin spider fauna in Sri Lanka — a country taking up merely 65,610 km2 — is already remarkably abundant. Moreover, apart from their diversity, these spiders amaze with their extreme endemism. While some of the six-eyed goblins can only be found at a few sites, other species can be seen nowhere outside a single forest patch.

“Being short-range endemics with very restricted distributions, these species may prove to be very important when it comes to monitoring the effects of climate change and other threats for the forest habitats in Sri Lanka”, explain the researchers.

In European folklore, goblins and brownies are known as closely related small and often mischievous fairy-like creatures, which live in human homes and even do chores while the family is asleep, since they avoid being seen. In exchange, they expect from their ‘hosts’ to leave food for them.

Similarly, at size of a few millimetres, goblin spiders are extremely tough to notice on the forest floors they call home. Further, taking into consideration the anthropogenic factors affecting their habitat, the arachnids also turn out to be heavily dependent on humans.

Sponge-like Cambrian fossil discovery


Allonia nuda. Credit: Derek Siveter/Tom Harvey/Peiyun Cong

From the University of Leicester in England:

Strange sponge-like fossil creature from half a billion years ago

June 19, 2018

Summary: A discovery of a new species of sponge-like fossil from the Cambrian Period sheds light on early animal evolution.

Scientists have discovered the fossil of an unusual large-bodied sponge-like sea-creature from half a billion years ago.

The creature belongs to an obscure and mysterious group of animals known as the chancelloriids, and scientists are unclear about where they fit in the tree of life.

They represent a lineage of spiny tube-shaped animals that arose during the Cambrian evolutionary “explosion” but went extinct soon afterwards. In some ways they resemble sponges, a group of simple filter-feeding animals, but many scientists have dismissed the similarities as superficial.

The new discovery by a team of scientists from the University of Leicester, the University of Oxford and Yunnan University, China, adds new evidence that could help solve the mystery.

The researchers have published their findings in the Royal Society journal Proceedings of the Royal Society B. The Leicester authors are Tom Harvey, Mark Williams, David Siveter & Sarah Gabbott.

The new species, named Allonnia nuda, was discovered in the Chengjiang deposits of Yunnan Province, China. It was surprisingly large in life (perhaps up to 50 cm or more) but had only a few very tiny spines. Its unusual “naked” appearance suggests that further specimens may be “hiding in plain sight” in fossil collections, and shows that this group was more diverse than previously thought.

Furthermore, the new species holds clues about the pattern of body growth, with clear links to modern sponges. It is too soon to say the mystery has been solved, but the discovery highlights the central role of sponge-like fossils in the debate over earliest animal evolution.

Dr Tom Harvey, from the University of Leicester’s School of Geography, Geology and the Environment, explained: “Fossil chancelloriids were first described around 100 years ago, but have resisted attempts to place them in the tree of life. We argue that their pattern of body growth supports a link to sponges, reinvigorating an old hypothesis. We’re not suggesting that it’s “case closed” for chancelloriids, but we hope our results will inspire new research into the nature of the earliest animals.”

Dr Peiyun Cong, from the Yunnan Key Laboratory for Palaeobiology, Kunming, China, and The Natural History Museum, UK, added: “The Chengjiang deposits of Yunnan Province continue to reveal surprising new fossils we could hardly have imagined. Together, they provide a crucial snapshot of life in the oceans during the Cambrian explosion.”

Rusty tussock moth lays eggs, video


This 19 June 2018 video shows a female rusty tussock moth laying eggs. The females of this species don’t have wings, so they don’t move much. Often, they lay their eggs on the cocoons of their chrysalis days; like in this video.

Toon Gevers in the Netherlands made this video.

Ancient Precambrian animals named after Attenborough, Obama


This 14 November 2014 video says about itself:

The fossils of the first animal can be found in the Ediacara Hills in South Australia. This animal is called Dickinsonia. It was a cushion like creature that lay on the seafloor. Its size ranged from a penny to a bath mat. It crept around very slowly to look for food.

From the University of California Riverside in the USA:

Two new creatures discovered from dawn of animal life

June 18, 2018

Earth’s first complex animals were an eclectic bunch that lived in the shallow oceans between 580-540 million years ago.

The iconic Dickinsonia — large flat animals with a quilt-like appearance — were joined by tube-shaped organisms, frond-like creatures that looked more like plants, and several dozen other varieties already characterized by scientists.

Add to that list two new animals discovered by a UC Riverside-led team of researchers:

Obamus coronatus, a name that honors President Barack Obama’s passion for science. This disc-shaped creature was between 0.5-2 cm across with raised spiral grooves on its surface. Obamus coronatus did not seem to move around, rather it was embedded to the ocean mat, a thick layer of organic matter that covered the early ocean floor.

Attenborites janeae, named after the English naturalist and broadcaster Sir David Attenborough for his science advocacy and support of paleontology. This tiny ovoid, less than a centimeter across, was adorned with internal grooves and ridges giving it a raisin-like appearance.

The discovery of Obamus coronatus was published online June 14 in the Australian Journal of Earth Sciences, or AJES, and the Attenborites janeae paper is forthcoming in the same journal. The studies were led by Mary Droser, a professor of paleontology in UCR’s Department of Earth Sciences. Both papers will be included in print in a 2019 thematic AJES issue focusing on South Australia’s Flinders Ranges region, where the discoveries were made.

Part of the Ediacara Biota, the soft-bodied animals are visible as fossils cast in fine-grained sandstone that have been preserved for hundreds of millions of years. These Precambrian lifeforms represent the dawn of animal life and are named after the Ediacara Hills in the Flinders Ranges, the first of several areas in the world where they have been found.

In the hierarchical taxonomic classification system, the Ediacara Biota are not yet organized into families, and little is known about how they relate to modern animals. About 50 genera have been described, which often have only one species.

“The two genera that we identified are a new body plan, unlike anything else that has been described”, Droser said. “We have been seeing evidence for these animals for quite a long time, but it took us a while to verify that they are animals within their own rights and not part of another animal.”

The animals were glimpsed in a particularly well-preserved fossil bed described in another paper published by Droser’s group that will be included in the Flinders Ranges issue of AJES. The researchers dubbed this fossil bed “Alice’s Restaurant Bed”, a tribute to the Arlo Guthrie song and its lyric, “You can get anything you want at Alice’s Restaurant.”

“I’ve been working in this region for 30 years, and I’ve never seen such a beautifully preserved bed with so many high quality and rare specimens, including Obamus and Attenborites”, Droser said. “The AJES issue on the Flinders Ranges will support South Australia’s effort to obtain World Heritage Site status for this area, and this new bed demonstrates the importance of protecting it.”

How spiders fly


This 1977 music video is called Flyin’ Spiderz – City Boy.

The Flyin’ Spiderz were a Dutch punk rock band.

However, there are also real flying spiders.

This 2015 video says about itself:

Flying Spiders: See Them in Action | National Geographic

Some say that flying is just falling with style. But for the Selenops spider it’s an important defense mechanism. Researchers recently discovered that this arachnid is able to flip itself over and steer quickly back to the safety of its home base when it needs to elude an approaching predator.

From PLOS:

Flying spiders sense meteorological conditions, use nanoscale fibers to float on the wind

The crab spider spins out tens of fine silk fibers for its aerial dispersal

June 14, 2018

Spiders take flight on the smallest of breezes by first sensing the wind, and then spinning out dozens of nanoscale fibers up to seven meters long, according to a study publishing June 14 in the open-access journal PLOS Biology by Moonsung Cho, Ingo Rechenberg, Peter Neubauer, and Christoph Fahrenson at the Technische Universität in Berlin. The study provides an unprecedentedly detailed look at the “ballooning” behavior that allows certain spiders to travel on the wind for hundreds of kilometers.

Many kinds of spiders engage in ballooning, either to disperse from their birth site, to search for food or mates, or to find new sites for colonization. While most ballooning spiders are juveniles or small adults, under 3 millimeters in length, some larger adults also balloon. Although the behavior has been studied before, these authors are the first to make detailed measurements of both the sensing behavior and the silk fibers that are used to catch the wind.

Through a combination of field observations and wind tunnel experiments, they found that large crab spiders (Xysticus species), about 5 mm long and weighing up to 25 milligrams, actively evaluated wind conditions by repeatedly raising one or both front legs and orienting to the wind direction. At wind speeds under 3.0 m/sec (7 mph), with relatively light updrafts, the spiders spun out multiple ballooning silks averaging 3 meters long, before releasing themselves from a separate silk line anchoring them to the blade of grass from which they launched. A single spider released up to 60 fibers, most of them as thin as 200 nanometers. These fibers differed from a drag line, which has been known as a ballooning line, and were produced by a separate silk gland.

This video says about itself:

3 April 2018

An Observational Study of Ballooning in Large Spiders: Nanoscale Multi-Fibres Enable Large Spiders’ Soaring Flight

The PLOS article continues:

The authors concluded that ballooning spiders actively sense wind characteristics and launch only when the wind speed and updraft are within relatively narrow ranges, increasing the odds of a productive flight. According to the fluid dynamic calculations the authors performed using their wind tunnel data, the spider relies on updrafts that form in the light winds into which they launch, further ensuring a successful flight.

“The pre-flight behaviors we observed suggest that crab spiders are evaluating meteorological conditions before their takeoff,” Cho said. “Ballooning is likely not just a random launch into the wind, but one that occurs when conditions most favor a productive journey.”