Spiders hear better than expected, new research

This video says about itself:

13 October 2016

In a test of hearing airborne noises, a small dark jumping spider stops moving abruptly (red pointer appears) when researchers broadcast a tone similar to the scary droning of the wings of a predatory wasp.

Video: G. Menda, Hoy Lab at Cornell

From Science News:

Be careful what you say around jumping spiders

Arachnids hear airborne sounds over greater distances than thought

By Susan Milius

8:00am, October 15, 2016

Accidental chair squeaks in a lab have tipped off researchers to a new world of eavesdroppers.

Spiders don’t have eardrums, though their exquisitely sensitive leg hairs pick up vibrations humming through solids like web silk and leaves. Biologists thought that any airborne sounds more than a few centimeters away would be inaudible. But the first recordings of auditory nerve cells firing inside a spider brain suggest that the tiny Phidippus audax jumping spider can pick up airborne sounds from at least three meters away, says Ronald Hoy of Cornell University.

During early sessions of brain recordings, Hoy’s colleagues saw bursts of nerve cell, or neuron, activity when a chair moved. Systematic experiments then showed that from several meters away, spiders were able to detect relatively quiet tones at levels comparable to human conversation. In a hearing test based on behavior, the spiders also clearly noticed when researchers broadcast a low droning like the wing sound of an approaching predatory wasp. In an instant, the spiders hunkered down motionless, the researchers report online October 13 in Current Biology.

Jumping spiders have brains about the size of a poppy seed, and Hoy credits the success of probing even tinier spots inside these (anesthetized) brains to Cornell coauthor Gil Menda and his rock-steady hands. “I close my eyes,” Menda says. He listens his way along, one slight nudge of the probe at a time toward the auditory regions, as the probe monitor’s faint popping sounds grow louder.

When Menda first realized the spider brain reacted to a chair squeak, he and Paul Shamble, a study coauthor now at Harvard University, started clapping hands, backing away from the spider and clapping again. The claps didn’t seem earthshaking, but the spider’s brain registered clapping even when they had backed out into the hallway, laughing with surprise.

Clapping or other test sounds in theory might confound the experiment by sending vibrations not just through the air but through equipment holding the spider. So the researchers did their Cornell neuron observations on a table protected from vibrations. They even took the setup for the scary wasp trials on a trip to the lab of coauthor Ronald Miles at State University of New York at Binghamton. There, they could conduct vibration testing in a highly controlled, echo-dampened chamber. Soundwise, Hoy says, “it’s really eerie.”

Neuron tests in the hushed chamber and at Cornell revealed a relatively narrow, low-pitched range of sensitivity for these spiders, Hoy says. That lets the spiders pick up rumbly tones pitched around 70 to 200 hertz; in comparison, he says, people hear best between 500 and 1,000 Hz and can detect tones from 50 Hz to 15 kilohertz.

Spiders may hear low rumbles much as they do web vibes: with specialized leg hairs, Hoy and his colleagues propose. They found that making a hair twitch could cause a sound-responsive neuron to fire.

“There seems to be no physical reason why a hair could not listen,” says Jérôme Casas of the University of Tours in France. When monitoring nerve response from hairs on cricket legs, he’s tracked airplanes flying overhead. Hoy’s team calculates that an 80 Hz tone the spiders responded to would cause air velocities of only 0.13 millimeters a second if broadcast at 65 decibels three meters away. That’s hardly a sigh of a breeze. Yet it’s above the threshold for leg hair response, says Friedrich Barth of the University of Vienna, who studies spider senses.

An evolutionary pressure favoring such sensitivity might have been eons of attacks from wasps, such as those that carry off jumping spiders and immobilize them with venom, Hoy says. A mother wasp then tucks an inert, still-alive spider into each cell of her nest where a wasp egg will eventually hatch to feed on fresh spider flesh. Wasps are major predators of many kinds of spiders, says Ximena Nelson of the University of Canterbury in Christchurch, New Zealand. If detecting their wing drone turns out to have been important in the evolution of hearing, other spiders might do long-distance eavesdropping, too.

Marbled orb-weaver spider couple asleep

This video from the USA says about itself:

26 September 2016

These attractive male and female Marbled Orb Weavers are taking a daytime nap together. The male has attached his “mating thread” across her web and I anticipated much spider action later, but alas other than a few tosses and turns as they slept in their webs when nighttime came they did not mate for at least a few hours and I was denied the chance to see Ms. Orb Weaver partake of Mr Orb Weaver – his last meal. I may lack the patience required for this video task.

How do they reproduce?

There is little information about the mating habits of marbled orb-weavers, although they may behave similarly to other members of their genus (Araneus). Females of these species emit pheromones to attract mates. To court mates, males spin a “mating-thread” across the female’s web. The male moves towards the female across this thread, plucking and vibrating it, and the female approaches him. The male touches the front of the female’s body with his legs, stroking her, until she hangs from the mating thread. Mating takes place in late summer and males mate several times. In some species of orb-weaving spiders, females eat their mates after breeding, this includes European garden spiders, which are closely related and live in the same area. Marbled orb-weavers may also do this; however, males mate multiple times and often survive mating, so cannibalism may not be as common in this species.

Spiders of Dutch Veluwe region, videos

This 8 July 2016 video shows a cross spider in its web in the Dutch Veluwe region.

This 12 July 2016 video shows spider’s eggs in the Dutch Veluwe region. The eggs are empty, as the spiderlings have hatched.

This 12 July 2016 video shows a spider which has caught a blue butterfly in the Dutch Veluwe region. In the background, a blackbird sings.

Seven new peacock spider species discovered in Australia

This video says about itself:

2 May 2016

Maratus splendens, a species of peacock spider that can be found in moister habitats in the southeast corner of Australia (New South Wales, Victoria) but has been reported also from Western Australia.

This spider was named in 1896 but no further individuals were noted in the literature until I rediscovered this species in 2009 and David Hill and I reported on it in Peckhamia 89.1. As far as I am aware this is the only footage ever published of this spider.

Maratus splendens is one of the smaller species of Maratus, about 3 mm in length. Its “target” pattern is similar to that of Maratus pavonis, but both species can be easily distinguished. The most conspicuous difference is the presence of a silvery black area on the “head” in Maratus splendens which Maratus pavonis lacks.

For still images of this spider, including some that show its size, see my flickr collection.

Music credit: birds, crickets and frogs of the Sydney suburb of St. Ives.

If you want to learn more about peacock spiders I have bad news, there is no book about them. However, you may find my facebook page sufficiently interesting and entertaining.

Otto, J. C. and D. E. Hill. 2016. Seven new peacock spiders from Western Australia and South Australia (Araneae: Salticidae: Euophryini: Maratus). Peckhamia 141.1: 1-101: here.

Tiny structures give a peacock spider its radiant rump. Pigments produce reds and creamy yellows, while nanostructures reflect blue hues: here.

Rare species of Dutch Veluwe region

This is a video about a strawberry spider.

Translated from Dutch NOS TV today:

Many rare plants and animals in the Veluwe

by Maino Remmers

The carrion beetle, the true lover’s knot moth, the Alcon Blue butterfly and certainly the wart-biter: all rare animals to be found plentifully in Hoge Veluwe National Park. The biodiversity is many times higher than expected. Plant and animal species which worldwide are on the red list are doing well in this central Dutch park. …

Ranger Henk Ruseler says that even species are found which were thought to no longer occur in our country. “The strawberry spider is said to be very rare, but it was during the last count found in various places,” he says.

During the annual census by volunteers … reptiles, butterflies and unusual mosses were also found.

29 species of dragonflies

Ruseler drives the pickup through a stream which originates from the ice age. Just around the stream are 29 different species of dragonflies and damselflies.

Surinamese Anansi stories, now part of Dutch heritage

This video from Jamaica says about itself:

Anansi and the Pot of Beans

19 October 2006

Anansi loves his grandma’s beans.

Translated from Dutch NOS TV:

Stories about spider Anansi on heritage list

Today, 02:27

The stories about the spider Anansi are from now on recognized on the National Inventory of Intangible Cultural Heritage in the Netherlands. This Caribbean storytelling tradition has its roots in slavery.

The Anansi stories have been told for centuries in West Africa. The slave trade spread them to Suriname and the Netherlands Antilles. The postwar migration brought them also to the Netherlands.

The Knowledge Centre of Intangible Heritage says the stories have a positive connotation, despite the dark past. They “contribute to strengthening the awareness and pride in heritage and culture.”

Dutch as frogs

The main character is a savvy spider which likes to fool other animals. Anansi is an ambivalent figure, a trickster, who also regularly harms his own wife or children.

In the days of slavery the narrators could also use the stories to embarrass the plantation owners. Dutch did not realize they were ridiculed in the fairy tales as frogs.

The stories were formerly told from parent to child, but now also through theater, schools and libraries. One of the most famous books about Anansi was written by the Surinamese former President Johan Ferrier.


The Anansi stories are an exotic addition to the heritage list, because nearly all have a European origin …

Of the 93 traditions 6 have a multicultural background, like the Surinamese koto and angisa costumes and tambú drums from the Antilles.

The non-Western traditions in the list:

Indies rijsttafel: Indonesia
Maroon culture: Suriname
Anansi: Suriname
Angisa and koto clothes: Suriname
Henna art: Turkey, Morocco
Tambú: Antilles

The addition of the Anansi stories to the heritage list will be celebrated today at the new Anansi tree in the Open Air Museum in Arnhem. Twenty storytellers will keep the stories alive for the visitors the coming time.

This video from the Netherlands says about itself:

The Power of Stories – Performance Wijnand Stomp (official trailer English)

1 October 2014

Theatre maker Wijnand Stomp and documentary maker Jean Hellwig present a stand-up storytelling show for people from 10 to 110 years old. In a mix of theatre, comedy and documentary they bring the audience in a cheerful way in contact with stories about the history of slavery.

The flamboyant Mister Anansi (Wijnand Stomp) sits on his porch in what he calls his “Anansi Tree”. From the branches hang old shoes. The window of his house is a television. It reveals in mini documentaries the special encounters during his journey along the Transatlantic triangle of the slave trade: Zeeland – Ghana – St. Eustatius. Mister Anansi tells about the new stories he created and his energetic Aunt Jewel drops by for a game of domino. With her hilarious First National Slavery Quiz she confronts the audience in a humorous way with the traces of slavery, under the motto ‘Hats off to slavery’.

In The Power of Stories Stomp and Hellwig weave a web of slavery in the Netherlands with personal stories from overseas. At the end of the show Mister Anansi lets his audience in notes write about their personal links with slavery. He keeps these stories in the shoes on his Anansi tree and lets the wind take them traveling.

SUITABLE for theaters, festivals, schools, libraries and cultural heritage institutions.

Wolf spider video

This video is about the Hygrolycosa rubrofasciata wolf spider. Males of this species drum with their bodies on old fallen leaves to attract females.

Erik Korsten in the Netherlands made this video.