Spider Art and Bioluminescent “Bombs”: Extreme Animal Mimicry

by Jan Thornhill

Exciting news for the world’s arachnophiles (spider lovers) broke late last year – a spider was discovered in the Peruvian Amazon that constructs a much larger fake spider in the center of its web. The as-yet-unnamed arachnid, likely belonging to the genus Cyclosa, creates its faux-spider masterpieces (some of which have eight legs!) out of leafy debris and dead insect parts. To further enhance the big-spider illusion, the real spider hides at the head of its creation and plucks strands of the web to make it vibrate.

The decoy spider's elaborate fake spider (Phil Torres)

So, does this spider make art? Nope, sorry – it’s not art. Creating a larger decoy of itself to frighten off potential predators is a form of self-protective mimicry that’s hardwired into the spider’s genes.

The most common form of mimicry is camouflage. Such visual mimicry can be as basic as a lion’s tawny coat blending in with the African savannah, or a gray-patterned moth disappearing when it lands on a similarly colored tree. More complex examples include caterpillars that pose as twigs, or leafy seadragons that are almost indistinguishable from seaweed, or spiders that, along with their webs, can be mistaken for bird droppings in both color and shape.

In Batesian mimicry, harmless species evolve to visually impersonate poisonous or distasteful species, which makes it much less likely that they, themselves, will be eaten. A master of this particular adaptation is the Indonesian mimic octopus.

The mimic octopus impersonates a flatfish, a scorpionfish, and a sea snake.

Octopuses are masters of disguise and can change color and pattern, and even texture, to match their surroundings. The mimic octopus’s self-defense strategy goes one step further – it’s a shape-shifter. This diminutive cephalopod has evolved an elaborate collection of behaviors that allow it to ape other marine animals. It stretches out its arms to imitate a scorpionfish flaring its poisonous spines, or hunkers down with only two legs extended in either direction to impersonate a venomous sea snake, or swims flattened out to mimic the shape of a flatfish. To date, this little octopus has been observed posing as fifteen other marine creatures! A fun twist to this amazing story is that scientists have recently witnessed a timid little black-marble jawfish, whose markings are strikingly similar to those of the mimic octopus, swimming perfectly disguised among the arms of one of these octopuses. A mimic mimics a mimic!

Australian chameleon gecko (Stewart MacDonald)

Decoy mimicry is yet another variation, in which animals have developed a means to either divert the attention of a predator or, conversely, to attract the attention of a potential meal.

One of the most radical practitioners of decoy mimicry is the gecko who, when threatened, is capable of discarding its own tail. The cast-off tails of some geckos flop around and writhe, offering a tantalizing alternative meal to predators while the geckos themselves escape. In Australia, the writhing, discarded tail of the chameleon gecko is made even more irresistible – it actually squeaks! Though self-amputation may sound like an extreme adaptation for survival, geckos are capable of growing replacement tails within a few months.

The adaptation of decoy mimicry isn’t confined to land animals. While studying life in the ocean’s depths aided by remote-controlled submarines, a group of scientists led by research zoologist Karen Osborn discovered seven new marine worms (annelids), some of which have developed a novel form of decoy mimicry – we just don’t know exactly what they’re mimicking.

Deep-sea marine worms release bioluminescent "bombs" (Karen Osborn)

These small bristly worms, the biggest no longer than a finger, come equipped with tiny balloons attached to their bodies near their heads. When one of these worms, which have been dubbed “green bombers,” is touched, it releases one or more of these bioluminescent “bombs” that give off intense green light for several seconds. It’s likely that a would-be predator, searching for a tasty morsel in the darkness, would be distracted by these mini floating lights while the worm is able to avoid being eaten by quickly swimming backwards out of harm’s way.

Update

August 21, 2018

I have to add this guy I came across in Chile. It's a fabulous example of automimicry – the kind where part of an animal's body looks like a more vulnerable part. 

Here's the first view I had of this insect:

"What a character!" I thought.  Kinda cute, and kinda homely at the same time, like an old shoe. 

Then I changed my camera angle... 

...and saw that what I'd thought was a face was actually the insect's rear end. 

How fabulous – it's abdomen was pretty much a replica of its head, complete with bulging red eyeballs! (If anyone knows anything about this beetle(?), I'd love to hear from you!!)

Here’s a link that has a video showing forward and backward movement of one of the newly discovered marine worms (genus Swima): http://news.sciencemag.org/sciencenow/2009/08/20-02.html

Here’s another that shows the mimic octopus in action: http://www.youtube.com/watch?v=H8oQBYw6xxc

More info about the decoy spider: http://blog.perunature.com/2012/12/new-species-of-decoy-spider-likely.html

And a delightful recording of the moment the decoy spider was discovered!: http://www.youtube.com/watch?v=RrWnZ7VySac

What Simon Cowell has taught me about writing

Okay, I confess (but don't tell anyone). I really like reality TV talent shows, particularly Britain's Got Talent and the X Factor. American Idol also has its moments. Over the last couple of years, I've been struck with the notion that there are equivalents between me and my writing and those would-be singers. Plugging away at my craft, facing the judgment of literary journals, agents, granting bodies and publishers, and dealing with the mostly rejections and occasion encouragement or minor success, I think I've learned from the successes and failures of the likes of Susan Boyle and Chris Maloney and the countless others whose names I have forgotten or never knew. Amid all the strutting and crooning and crying, I've gleaned a think or two. Here's my attempt at summarizing what Simon Cowell and his friends have taught me:

1 There are many reasons that people with talent don’t make it. These reasons might include:

·         Someone judging had a fight with their girlfriend/boyfriend/hairdresser

·         Someone judging is drunk or under the influence of narcotics

·         Someone, like a producer, gave bad advice

·         The person with talent chose the wrong song/genre/medium, etc.

·         The person with talent has the personality of a wet noodle.

2  There are many differences in opinion; don’t trust what any one person says, but if lots of people say the same thing, they are more likely to be right.

3  Just because you think you have talent doesn’t mean you actually do. We can delude ourselves.

4 Just because you don’t think you have much talent, doesn’t mean you don’t. We can underestimate ourselves.

5 Sometimes you should listen to no, and sometimes you shouldn’t. (See 2,3, and 4 above.)

6 Young people are capable of a great deal, not just in terms of raw talent, but drive, dedication and maturity.

7  Humans like surprises, in art as well as in people.

8  Everyone likes a good rags to riches story, but especially the rags part.

9 People considered strange in everyday life are often fascinating and attractive if put on a stage. Big personalities need distance to be most appreciated. NOTE: there is such a thing as being too weird (see below).

 10.   Talent in restraint with the occasional burst of brilliance is ideal. A wild streak is great, as long as it is just a streak and not a full immersion.

  11.   Humility is appealing. So is authenticity.

 12.   Hard work and determination are essential, but not enough on their own.

  

 13. There is a big difference between good and great.

The Science of Snow

I live in Regina, Saskatchewan. We joke that weather is more than small-talk here. Too often, it's what everyone is talking about.

This winter, it's a topic with a vengeance. According to Environment Canada, we've been setting snow records this year:

- a new daily record of 24 cm November 9
- more snow in the first three weeks of November than we had all last winter
- the snowiest November since the 1880s

In December, the snow continued. And with another 20+ cm dump yesterday, January just seems like more of the same.

As you can probably tell, I'm not a fan of snow. But if you can't get away from it, you might as well dig into it. So I'm digging out a copy of Snowflake Bentley by Jacqueline Briggs Martin, searching on the Internet, and turning to science to help me beat the winter blahs.

Snowflake Bentley tells the story of Vermont farmer Wilson Bentley, who studied snow and took pictures of snow crystals. In the book, someone tells Bentley that "snow in Vermont is as common as dust." I laughed when I read those lines. Did you know that snowflakes start out as tiny crystals no larger than a speck of dirt or dust, and join with other crystals when they fall? Most snowflakes are six-sided, and the size of one flake depends on the number of crystals forming it. When I was a child, I remember catching snowflakes on a mitten. An individual snowflake can be quite beautiful.

That's hard to believe when you look at the pile of snow in my front yard these days. Thank goodness for neighbours with snowploughs! Lately I haven't been looking at the individual snowflakes, like Bentley did, because there's just been too much of it. Some of it is packed hard; some is powdery; some has already melted and frozen often enough to form ice underneath.

The National Snow and Ice Data Centre (NSIDC) has collected a whole database of types of snow. The NSIDC site talks about blizzards, flurries, and snowbursts like the ones we've experienced this winter. We're too familiar with blowing snow and drifting snow. That's all we seem to see on the roads lately. The site lists some unusual types too, like "névé" (refrozen and compacted) and "graupel" (rounded snowflakes or snow pellets).

My favorite is hoarfrost. We've certainly had what feels like record amounts of hoarfrost on the trees this winter, but I haven't taken the time to enjoy the beauty of it. I think I'll go out and take some more pictures, as soon as it warms up.

Meanwhile, I thought I'd share some of the snow sites I found:

National Snow and Ice Data Centre

http://nsidc.org/cryosphere/snow/science/index.html

Science of snow: FamilyEducation.com

Snow Day by L L Melton

http://fun.familyeducation.com/childrens-science-activities/winter/35037.html

Study snow science: University of Montana

http://www.montana.edu/wwwes/programs/snow.htm

Please leave a comment and share interesting facts about snow or snow science with us.

By Marie Powell

Notes from a Low Country

 

     I was born and raised in The Netherlands. Not Holland. ‘Holland’ refers only to two of the twelve provinces. The Netherlands is a small country in Europe. It is a little over 41 thousand square kilometers (or 16 thousand miles). That means that you can get almost 17 times its size out of the state of Texas!
    A few hundred years ago the country was even smaller. It lies at the  western edge of Europe, where big rivers flow into the sea. Much of the country is very low land and has often flooded. In fact, most of the country is under sea level and the lowest point in The Netherlands is an amazing 7 meters (20 feet) below sea level! 

Even its name tells you a lot: ‘Nether’ means ‘low’: low lands.
    Some 700 years ago people decided to use windmills to help drain the land. Not only did they use windmills to pump water away from flooded lands, they also started using them to reclaim land. They built dikes around a low lying area and then used the windmills to pump the water to the other side of the dike, into a river.
    Only twenty years ago, the country added a whole new province to its size by reclaiming land from the sea. There used to be a large bay, the Zuiderzee. People built a huge dike to dam it off from the sea, and then started pumping water out of the bay until the land laid dry. The new province, called Flevoland, added 1,400 square kilometers to the little country!

    Many windmills are still standing throughout the country. Some are used for pumping water while others use the power of the wind to grind grain and other crops. There are many different types of mills. Sometimes the miller even lives inside the windmill. Can you image living in a house that is round or octagonal, that shakes and creaks in the wind?
    One spot in The Netherlands is especially famous for its beautifully preserved windmills. On a sunny day you can sometimes see 19 windmills happily turning their huge arms in the breeze. Not only do they still pump water away from the low-lying polder land, they also attract thousands of visitors who come to see the spectacular sight!

Nowadays, new wind mills generate power by harnessing the wind. The new type of windmill is altering the landscape but helping to generate power from a renewable resource. The amount of power generated by a new windmill depends on the strength of the wind and the number of days of wind per year. The average Dutch household uses 3.400 kWh per year. A smal 'wind park' (several windmill turbines together) produces 21.900 MWh, enough electricy for some 6,000 households!

BTW: Wooden shoes have been used in The Netherlands for hundreds of years. You can best compare them to rubber boots: they are handy to use when it is muddy in your yard, they keep your feet dry and they come off much easier than boots!
It is not true that everyone in The Netherlands wears wooden shoes: just some farmers or gardeners choose to use them. But they have become a tourism symbol for the small country!

Margriet Ruurs is the author of 27 books for children. Her book Children Around the World will be published by Kids Can Press in 2014.

Crunchy Science

There are a lot of bugs in Hawaii. Most of them make loud, crunchy sounds as you ride over them with your bike, or accidentally squish them with your sandals. Not once have I ever thought to collect them and serve them up for dinner. The local term for delicious, "broke da' mouth", would certainly not apply to these oreo cookie sized cockroaches.
Which brings me around to the pictures above taken at a recent dinner party at our home as part of the Celebrate Science annual dinner with the authors. Each year we try to have a themed dinner for our illustrious guests. One year it was a trip to the Wine Research Centre at UBC. Another year it was the Science of Wine and Cheese where we learned that the perfect cheese to pair with Ice Wine was oddly stinky blue cheese.
It was with great trepidation and a serious amount of alcohol that a somewhat reluctant group of science lovers enjoyed some unusual appetizers or pupus as we call them on the big island.
Professor Murray Isman, Dean of Land and Food Systems fried up a pan of juvenile and mature locusts and baked a tray of meal worms for our enjoyment. The Dean's wife, Susie gave it a wide pass as she is allergic to shellfish and much to her glee, the locusts have outer coatings which contain chiton, the same material that is found in shrimp and lobster. As for taste, anything with enough garlic, butter and a dash of liqueur is pretty good. The locusts were crunchy and quite good, while the meal worms were somewhat like peanuts. They were an acquired taste.
While I might not want to serve these on a regular basis, about half the world includes insects as part of their diet. Bugs, as it turns out are the perfect food.
The average beef burger contains only 18% protein and 18% fat; the same amount of grasshopper would give you 60% protein and only 6% fat. The fat in insects is unsaturated, making them a healthier alternative to meat. Beef contains 9 mg of iron- while there is 2 mg for the same weight in grasshoppers.
Now getting into the eat locally trend, locusts can be home grown. They have a very small carbon footprint . If you raise your own they don't have to be transported over any distance by truck, train or plane. No machines are used to harvest them and obviously pesticides can't be used in raising them. They don't need steroids or additives. No questions about ethically raising these bugs and killing is done in the pan. Grasshoppers and their like are not GMO as who in their right mind would want to create cow sized bugs?
There is no shortage of these creatures around the world. Earthworms, meal bugs, locusts and other edible creepy crawlies are found in abundance everywhere. Before you get too self righteous about eating bugs, don't be so smug. Ground up bits of bugs find their way into processed foods every day. In fact you would be surprised just how many you are eating each time to have a something powdered, baked or floured.
Next year instead of carving up a roasted turkey for the holiday, try making an entree of sautéed locusts with a side of meal worms. The earth will thank you for it.
Mele Kalikimaka (Hawaiian for "Merry Christmas". The language hasn't anything for Happy Chanukah)

Location:Hawaii

Fuel Spills

Do science and outdoor sports go together for you? They do for me! I do a lot of thinking when out in my kayak. Sometimes the things I see when kayaking remind me of birdwatching and climate change science. But most recently, while out in my kayak I passed a floating plastic bag that might have blown off a boat, and a sunken tin pie pan that was probably frisbee-ed from shore. Seeing human trash reminded me of why I had to get to my computer and write this post. There have been a series of fuel spills locally, where I live in Saanich, part of Victoria.
You can read about one of the first recent spills in the Saanich News in their article appropriately titled "Oil spill stains urban miracle." It's on the front page, with a sub-heading "Catastrophe strikes Coho-laden creek." I hadn't thought of an urban creek being the subject of study for working biologists, but it is. And there are school visits to the creek as well, so that students can learn about Nature in their own home neighbourhood.

My friend John Herbert took this photo of Colquitz Creek. That's the salmon stream that we've written about here, the one that runs from Beaver Lake through Panama Flats to Portage Inlet.

This spill was from a home heating oil tank that leaked. It happened when a fuel delivery was made to the wrong address, and the wrong home's unused tank was filled with home heating oil. A pipe leading from the fuel tank sprung a leak, and over a few days released an estimated 1,000 litres of heating oil into Swan Creek, which drains into Colquitz Creek. Once the oily sheen on the stream was pointed out to Saanich municipal workers, they traced the fuel up to the source of the leak. Other leaks have since been traced back to other tanks.


These fuel tanks weren't mine or in my own neighbourhood, but I must have walked within a hundred yards of them several times before eating and relaxing at a nearby home of friends or family. That's it, for me. Not in my back yard. Not in my friends' and families' back yards. Accidents happen, but fuel tanks are owned by people who can look after them. No excuses. When I walked back from the beach, I put the kayak away and looked at my landlady's fuel tank. No visible leaks. Not in my yard.
I'm no fuel-servicing expert. I'm not a marine biologist, or a fresh-water biologist either, but I do get out on the water often in my kayak. Every small boat user interacts hands-on with the water in a personal way. We can understand the effects of fuel spills on waterways, effects that some people don't easily understand because they don't see the plants and animals like we do. Now I'm trying to put that understanding to use.
Another recent spill of home heating fuel into the watershed in Greater Victoria can be read about here at the Times-Colonist newspaper website. The Times-Colonist article noted that:
A fact sheet from the provincial Environment Ministry says homeowners are potentially liable for cleanup costs whether they are aware of the existence of an oil tank or not.
Scary thought, eh? And home insurance doesn't cover fuel spills. One of the recent cleanups cost the homeowners $35,000.
Apparently, an old fuel tank can go from "looks ok" to "leaking" pretty darned fast... even when it's been checked by an expert from the fuel oil company. As one homeowner with an unexpected leak said to the Saanich News:
“We had a platinum protection plan where (our oil company) would do sonic testing of the tank to check the thickness of the walls. We were also using their oil that’s supposed to have additives in it that retards corrosion,” Keith says. “We were sort of relying on that plan, to some extent, to give us a head’s up if something was up. At the end of the day that didn’t help us out. We’re kicking ourselves now – it was an old tank, why didn’t we just replace it? For $2,000 we could’ve avoided a ton of grief.”

It seems that tank leaks can happen suddenly and aren't as obvious as the crack along the coaming in my second-hand Pamlico kayak from Wilderness Systems.
So I will remember the statements by experts in the local newspapers: twenty-year-old fuel tanks can and do fail suddenly. I don't have to be a fuel expert to help my landlady make a proper plan for the fuel tank at her house! That's practical science we can put to good use. With planning, this home heating system will never be the cause for an expensive and environmentally damaging spill.
We can't stop all the fuel spills in the world, but we can each look after our own equipment. And if you see any fuel spilled on the ground or water in BC, in town or out in the boonies, call the 24-Hour Spill Line toll-free at 1-800-663-3456.

Talking to Your Dog is Not As Crazy As You Think

by L E Carmichael

Any dog owner will tell you that their pet understands them - recognizes words, follows commands, and somehow knows when they need a sympathetic snuggle.  Scientists call this communicative skill and intelligence "social cognition."  It's the set of knowledge and behaviours that animals - including humans - need in order to survive in social groups.  In the case of the dog, humans are a natural part of that social group, and language is one of the major ways humans communicate.  Use of human language by dogs is a developing field of study.

Thanks to Othal via Wikimedia Commons for this
gorgeous border collie photo!

Take Rico, for example.  Rico's owners claimed that the border collie knew the names of 200 objects, and would retrieve each item on request.  Scientists were skeptical at first - after all, a horse known as "Clever Hans" wasn't actually counting, but reading his trainer's body language.  However, when Rico had to go into a separate room to find the toy his owner asked for, where he couldn't receive any additional clues, he still got it right 37 out of 40 times.  

Rico's vocabulary, though on par with trained apes, dolphins, and parrots, wasn't that interesting to scientists.  What they wanted to understand was how Rico learned the names of new objects.  They placed unfamiliar items in the room with toys that he knew, then asked him to retrieve using a brand new word.  Seven out of 10 times, Rico brought the new object.  He was using exclusion learning - "I know the names of all of these things, but mom used a different word, and therefore...."  This "fast mapping" is the same technique human children use during language learning, and Rico's success rate was comparable to that of an average 3-year-old.

Scientists have shown that when humans generalize new words to categories of objects, they do so based on shape, rather than size or texture.  For example, if shown a ball for the first time, kids will extend that label to other spherical objects.  Similarities in size and texture are less important - a golf ball and a whiffle ball are both balls.  Would the same true for dogs?

A second border collie, Gable, was taught that the word "dax" represented a small, fuzzy, U-shaped object.  He was then asked to identify the dax among objects with different sizes, shapes or textures.  Unlike people, Gable generalized the word dax to objects the same size, not shape, as the original.  He also used texture as an indicator.  

Scientists believe that humans rely on shape because, in general, vision is our dominant sense.  It's less clear why dogs may be relying on different indicators, but the results suggest that there could be fundamental differences in the way dogs and people learn and understand language.  Which makes it even more incredible that we manage to communicate at all!

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The video of Gable is from: van der Zee et al (2012) Word Generalization by a Dog (Canis familiaris): Is Shape Important? PLOS ONE: e49382.  You can find more videos at the article's home page.