Category Archives for Peacock Spider

I travelled Australia looking for peacock spiders, and collected 7 new species (and named one after the starry night sky)



Heath Warwick, Author provided

Joseph Schubert, Museums Victoria

After I found my first peacock spider in the wild in 2016, I was hooked. Three years later, I was travelling across Australia on a month-long expedition to document and name new species of peacock spiders.

Peacock spiders are a unique group of tiny, colourful, dancing spiders native to Australia. They’re roughly between 2.5 and 6 millimetres, depending on the species. Adult male peacock spiders are usually colourful, while female and juvenile peacock spiders are usually dull brown or grey.



Read more:
The spectacular peacock spider dance and its strange evolutionary roots

Like peacocks, the mature male peacock spiders display their vibrant colours in elegant courtship displays to impress females. They often elevate and wave their third pair of legs and lift their brilliantly coloured abdomens – like dancing.

Maratus laurenae. Male peacock spiders have brilliant colours on their abdomen to attract females.
Author provided

Up until 2011, there were only seven known species of them. But since then, the rate of scientific discovery has skyrocketed with upwards of 80 species being discovered in the last decade.

Thanks to my trip across Australia and the help from citizen scientists, I’ve recently scientifically described and named seven more species from Western Australia, South Australia and Victoria. This brings the total number of peacock spider species known to science up to 86.

Spider hunting: a game of luck

Citizen scientists – other peacock spider enthusiasts – shared photographs and locations of potentially undocumented species with me. I pulled these together to create a list of places in Australia to visit.

I usually find spider hunting to be a relaxing pastime, but this trip was incredibly stressful (albeit amazing).

The thing about peacock spiders is they’re mainly active during spring, which is when they breed. Colourful adult males are difficult – if not impossible – to find at other times of year, as they usually die shortly after the mating season. This meant I had a very short window to find what I needed to, or I had to wait another year.

Classic.

Even when they’re active, they can be difficult to come across unless weather conditions are ideal. Not too cold. Not too rainy. Not too hot. Not too sunny. Not too shady. Not too windy. As you can imagine, it’s largely a game of luck.

The wild west

I arrived in Perth, picked up my hire car and bought a foam mattress that fitted in the back of my car – my bed for half of the trip. I stocked up on tinned food, bread and water, and I headed north in search of these tiny eight-legged gems.

My first destination: Jurien Bay. I spent the whole day under the hot sun searching for a peculiar, scientifically unknown species that Western Australian photographer Su RamMohan had sent me photographs of. I was in the exact spot it had been photographed, but I just couldn’t find it!

I travelled across Denmark, Western Australia.
Author provided

The sun began to lower and I was using up precious time. I made what I now believe was the right decision and abandoned the Jurien Bay species for another time.

I spent days travelling between dramatic coastal landscapes, the rugged inland outback, and old, mysterious woodlands.

Kalbarri Gorge, Western Australia, where Maratus constellatus was found.
Author provided

I hunted tirelessly with my eyes fixed on the ground searching for movement. In a massive change of luck from the beginning of my trip, it seemed conditions were (mostly) on my side.

With the much-appreciated help of some of my field companions from the University of Hamburg and volunteers from the public, a total of five new species were discovered and scientifically named from Western Australia.

The Little Desert

Two days after returning from Western Australia, I headed to the Little Desert National Park in Victoria on a Bush Blitz expedition, joined by several of my colleagues from Museums Victoria.

I’d thought the landscape’s harsh, dry conditions were unsuitable for peacock spiders, as most described species are known to live in temperate regions.

Capturing spiders in a bug net.
Heath Warwick, Author provided

To my surprise, we found a massive diversity of them, including two species with a bigger range than we thought, and the discovery of another species unknown to science.

This is the first time two known species – Maratus robinsoni and Maratus vultus – had been found in Victoria. Previously, they had only been known to live in eastern New South Wales and southern Western Australia respectively.



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Our findings suggest other known species may have much bigger geographic ranges than we previously thought, and may occur in a much larger variety of habitats.

And our discovery of the unknown species (Maratus inaquosus), along with another collected by another wildlife photographer Nick Volpe from South Australia (Maratus volpei) brought the tally of discoveries to seven.

What’s in a name?

Writing scientific descriptions, documenting, and naming species is a crucial part in conserving our wildlife.



Read more:
Spiders are a treasure trove of scientific wonder

With global extinction rates at an unprecedented high, species conservation is more important than ever. But the only way we can know if we’re losing species is to show and understand they exist in the first place.

  • Maratus azureus: “Deep blue” in Latin, referring to the colour of the male.
Maratus azureus.
Author provided
  • Maratus constellatus: “Starry” in Latin, referring to the markings on the male’s abdomen which look like a starry night sky.
Maratus constellatus.
Author provided
  • Maratus inaquosus: “Dry” or “arid” in Latin, for the dry landscape in Little Desert National Park this species was found in.
Maratus inaquosus
Author provided
  • Maratus laurenae: Named in honour of my partner, Lauren Marcianti, who has supported my research with enthusiasm over the past few years.
Maratus laurenae
Author provided
  • Maratus noggerup: Named after the location where this species was found: Noggerup, Western Australia.
Maratus noggerup
Author provided
  • Maratus suae: Named in honour of photographer Su RamMohan who discovered this species and provided useful information about their locations in Western Australia.
Maratus suae
Author provided
  • Maratus volpei: Named in honour of photographer Nick Volpe who discovered and collected specimens of this species to be examined in my paper.
Maratus volpei
Nick Volpe, Author provided

These names allow us to communicate important information about these animals to other scientists, as well as to build legislation around them in the case there are risks to their conservation status.

I plan on visiting some more remote parts of Australia in hopes of finding more new peacock spider species. I strongly suspect there’s more work to be done, and more peacock spiders to discover.The Conversation

Joseph Schubert, Entomology/Arachnology Registration Officer, Museums Victoria

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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The spectacular peacock spider dance and its strange evolutionary roots


Michael Kasumovic, UNSW Australia; Damian Elias, University of California, Berkeley, and Madeline Girard, University of California, Berkeley

With their flamboyant dress, and fabulous song and dance routines, tiny peacock spiders have captivated the hearts of the internet.

Many species have courtship displays, but few are as complex as that of the peacock spider. But why does this little Casanova put on such a spectacular show, particularly when we’d expect evolution to favour simplicity?

We set up an elaborate experiment to find out. But before we raise the curtain on that, we need to set the scene.

What’s in a signal?

Imagine a high school suitor picking up his date for the prom, and we might picture him exiting a limousine wearing a tux with bouquet in hand. We’d argue (and he’d likely agree) that each of these things improves his chances of impressing his date.

But what kind of information is his date gleaning from these signals? Is he trying to make sure that his date notices that he can afford extravagance, and therefore, he’s signalling his wealth and success? Or does the car signal his wealth, his tux his desire to look good, and his flowers his love for nature? If so, then these aspects work together to signal his overall suitability as a mate.

Regardless of what motivated his signals, we’d probably all agree that that this wide-eyed youngster is trying to impress his date. But is this true? Isn’t it just as likely that this extravagance is signalling to other males that they should stay away? Or is it just the social norm to appear in a limo with a tux and flowers, otherwise he’d look out of place?

This is the problem biologists have faced when trying to explain the existence of complex courtship that uses multiple traits: what is driving a male’s improved dress and his desire to impress?

The answer has escaped biologists because single, simple traits are generally the norm. Sometimes we have species that use multiple traits, like the colourful plumage and elaborate dances of some birds, but the use of multiple traits is very rare.

Biologists’ favourite example of courtship complexity is the birds of paradise.

With 39 different species, there is a diversity of vocal signalling, extreme variation in colouration and dances that accompany both. But despite our desire to explain this diversity as a result of female preference, there is no such evidence. Until now.

The extreme variation in courtship found in birds of paradise, and the difficulty in observing them.

Along came a spider

Peacock spiders (Maratus volans) are a group that is unique to Australia. With more than 40 documented species, and likely many more to discover, it is an example where citizen science is helping us understand the diversity in this group.

It is this diversity, abundance and their extroverted courtship behaviour in the lab that really allows us to explore why such complexity exists and what it means.

You can see the camera above the mating arena surrounded with acetate to provide a safe habitat for them to court. The laser virbrometer is just behind Maddie Girard.
Maddie Girard

So to explore peacock spider courtship, we collected 128 male and female spiders from around Sydney and brought them back into the lab. Then by creating a courtship arena consisting of nylon stretched over a wooden frame and naturalising it with some leaves, we were able to record the behaviours using a video camera and the vibrational songs that males produce using a laser vibrometer.

What we found was rather interesting. We discovered that males use several different aspects to court a female.

A video of a different components of the courtship males use to court a female.

Males use vibrations early on to gain a females attention. When they are sure she’s watching, they begin to escalate courtship by waving their front legs and showing off their fan. If the female begins ignoring the male, they change their strategy and begin vibrating more.

We found that there was a very low success rate: only 16 of the 64 males were successful! And it was visual signalling effort that best predicted success – so the tux was more effective than the serenade. It was the males that were best able to show off their fans while ensuring that females were constantly watching.

Our other interesting finding was that females were very clear about what they didn’t like. During courtship, if a female signalled her displeasure by waving their abdomen back and forth, there was a low chance of success. Males therefore received feedback to their performance. So it seems that being attentive pays off.

The low success rate when courting virgin females (and potential death), coupled with the fact that none of our mated females re-mated suggests that success is very low in nature and only the males that best show off their stuff succeed.

A displeased female Maratus volans that’s taken it out on her suitor.
Maddie Girard

What we can learn from little spiders

Female peacock spiders are picky, and it’s this scrupulous behaviour that has likely led to the strong selection for the complexity of male courtship.

Understanding this is important because it provides us with insight into the evolution of traits as signals and the situations necessary for such complexity to evolve. These answers have eluded biologists so far because natural variation in the success of courting males is extremely difficult to observe.

The next step is to explore whether the species that show increased complexity have even pickier females.

But for know, we can learn from these little Aussie wonders and say that if you’re strutting your stuff on the dance floor or through virtual interactions on the internet, pay attention to what the female has to say. Perhaps you may increase your chances as you’ll know where to put your effort.

Check out the video below to learn more about Maddie and some of the diversity in courtship from other species.

The diversity of courtship from other species of Maratus produced by SciFri.

The Conversation

Michael Kasumovic, Evolutionary Biologist, ARC Future Fellow, UNSW Australia; Damian Elias, Assistant Professor in Evolutionary Biology, University of California, Berkeley, and Madeline Girard, PhD student in evolutionary biology, University of California, Berkeley

This article was originally published on The Conversation. Read the original article.