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Bartholomew Says Hello June 22, 2010

Posted by Mrs Weird Scientist in Animals, Brain Power, Deep Sea, Easy As Pie, Environment, Evolution, Ocean.
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If this blobfish could talk, I think it would ask for us humans to give it some space. Maybe then it would have reason to smile. Credit: Greenpeace

Okay well, I made up the name Bartholomew and this interesting creature can’t really speak.  But if it could, I imagine it might say something like “Please leave me alone!”  So, just what is this odd, slimy thing and why would it want us to stay away?

Meet A Blobfish

With the formal name of Psychrolutes marcidus, the blobfish is definitely not the world’s prettiest fish.  It is, however, on the verge of extinction according to researchers at the University of York in England.  For blobfish, home is 800 meters into the ocean, just off the southeastern coast of Australia.

But unfortunately, excessive fishing with nets along the bottom of the ocean has jeopardized the well-being of the blobfish.  It starts with overfishing at less deep and murky depths.  After reducing populations up there, not much is left.

To compensate, we do something called bottom trawling, which takes us even deeper into the ocean.  Here, we are fishing along the sea floor.  It’s bad news for Bartholomew and all the other blobfish down there.  No wonder poor Bartholomew looks so sad.

These blobfish may look like your grumpy Great Aunt Martha but they're probably unhappy for another reason. Overfishing is threatening their livelihood. Credit: NOAA Alaska Fisheries Science Center.

A Day In The Life Of Bartholomew

Just humour me here and let’s keep the name.  So what’s life like for Bartholomew?  You won’t see it for yourself because Bartholomew lives deep in the ocean, far away from our eyes.

That peculiar body serves a purpose, letting Bartholomew sort of float above the sea floor.  Instead of using a bunch of energy to move, Bartholomew keeps movement easy and light.

How big is this body?  A blobfish usually grows to approximately 12 inches (30 centimeters).  In fact, I just picked up a comic book I will soon be reviewing here on the blog, and it’s about the same length as a blobfish.

A Floating Feeder

And boy oh boy, feeding is an interesting activity for the blobfish.  While you or I take an active role in eating – we open our mouths and put food inside – the blobfish does it another way.  When Bartholomew feeds, it means just drifting along, swallowing food particles that float in its mouth.

Ugliness Comes In Many Forms

Bartholomew is yet another example of the consequences from overfishing.  Without adequate regulations around deep sea trawling, our ‘hello’ to Bartholomew may soon be a ‘goodbye’ instead.  While his appearance may be ugly, some might say that the actions of humans are far uglier.

The Return Of Bed Bugs – Smarter Ones January 13, 2010

Posted by Mrs Weird Scientist in Animals, Evolution, Insects, Tough Stuff.
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Your mattress may be home to more than your pillow or favorite stuffed animal. It could be the home of bed bugs!

The title reads like a horror movie but for those who have battled it out with bed bugs, it makes a lot of sense. Others might think that ‘don’t let the bed bugs bite’ was just some bedtime line their parents used as a cute joke.

In fact, let’s see now who knew that bed bugs really existed. Try out the poll below (be honest!).


Bed Bug Basics

Bed bugs are small, reddish brown insects that feed on human blood, which engorges them and makes them bigger. They are from the insect family Cimicidae and common bed bugs are formally called Cimex lectularius. They tend to be most active at night, coming out of the cracks in walls or bed frames and other hiding places to get their bloody grub. They can travel in suitcases, so hotels are a hot spot for bed bugs as well as other places that see plenty of people coming and going. Cornell University has an ace fact sheet to give you the lowdown on bed bugs. You can also have some fun playing around on Pest World for Kids, a website created by the National Pest Management Association (NPMA). But let’s get back to finding out why these wee pesky critters have returned and what makes them smarter today.

Gone But Not For Long

Here we have a bed bug hiding in a wood bed frame. The bed bug looks like it's having a Sunday snooze but I bet it's getting rest so it can hunt for fresh blood! Image credit: Thomas Oldani

Bed bugs were once nearly destroyed in our modern environment, where the use of chemicals such as dichlorodiphenyltrichloroethane – otherwise more easily known as DDT – kept these beasties at bay. DDT is a pesticide that is either very useful or very toxic, depending on who you ask or what journal study you read. Ultimately though, it was banned.

The Good And Bad Of DDT

DDT was used to keep mosquitoes under control, mostly because they spread malaria. It was used to keep lice numbers down too. So what happened when it was banned? As somewhat of a side effect of its use, DDT had kept bed bug numbers down. After it was banned, a bunch of other chemicals were used to treat bed bug infestations. The bed bugs, however, got smart and developed resistance to some of these chemicals. That resulted in a big UH OH for society as bed bug infestations are now on a major rise! Scientists from the University of Massachusetts Amherst and Korea’s Seoul National University decided that it would be important to find out more about resistant strains of bed bugs in New York. The work was published in the Journal of Entomology. Let’s see what they discovered, shall we?

When researchers got busy observing bed bugs in New York, they found these pests had mutations in their nerve cells. What does this mean? It means they are resistant to the chemicals used to kill them. Where the chemicals would previously have paralyzed and killed the bed bugs, the mutations mean that bed bugs are now outsmarting their opponents – us!

Let The Bed Bug Collecting Begin!

To get the scoop on bed bug resistance, researchers took a sample of easily controllable ones from Florida and compared these to ones from New York that were harder to deal with. So just how resistant were these little bugs?

Look at this partially engorged bed bug. It probably looks similar to the bed bugs in Milan after they feasted on my blood. Oh, and a fun fact of the day: the Italian word for bed bugs is cimice dei letti.

Researchers found that the bed bugs in New York had up to 264 times the resistance to the modern chemical used to kill bed bugs – deltamethrin. If we picture a nerve cell, it has these little sodium channels on the outer membrane bit. This is where the flurry of nerve impulses come to life. In the New York bed bugs, this nervous system mutation means they can keep feeding long after those Florida ones have been exterminated.

Grossaroo

When I was in grade 3, I made up the word ‘grossaroo’ to describe anything yucky. This word is fitting in the case of what happened to me recently when I was working at an agency in Milan. After a few nights at what seemed to be a nice corporate flat, I began to get loads of itchy, inflamed red bites. I awoke one night to find a flattened-looking bug moving across my otherwise clean, crisp white sheets.

I yelped and quickly squished it with my slipper, only to see it turn into a smattering of blood, which it just took from its recent feeding of my body! Just after, I saw another one. By morning, my bed looked like a crime scene with all those splats of blood and bugs. Eeek! Fortunately, I got moved to a new place and had everything washed. Hopefully, those Milan bed bugs weren’t too hard for the building owners to get rid of, unless they’re resistant beasts like those New York ones.

Bed Bug Warrior To The Rescue

So now you know (if you didn’t already!) that bed bugs do exist. Not only that, but they’re continually evolving to get smarter, doing so in ways that make it harder to get rid of them. For now, you can be smart by being extra cautious when traveling. Always check for signs of bed bugs around the mattress and furniture. Since not everyone shows bites from these little pests, prevention will remain the best line of defense. And while it’s not necessarily smart, it sure is fun when checking for bed bugs to yell “YOU’RE GOING DOWN!” If your parents ask what you’re doing, you can explain that you’re the self-appointed family warrior here to protect everyone from bed bugs.

Image credits: Unless otherwise specified, images courtesy of the National Pest Management Association.

Evolution Gets Colorful August 24, 2009

Posted by Mrs Weird Scientist in Brain Power, Environment, Evolution, Tough Stuff.
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Summer is still going strong but soon it will be fall – a time when we can enjoy the pretty autumn leaves. Or as I always like to do, throw leaves at my wee dog and race through the massive piles of foliage.

Unless you’ve traveled a bit and have a sharp eye for detail, you might not have noticed that autumn leaves are usually red in America but yellow in Europe. Seems strange, doesn’t it? If you’re wondering why, then you’re not the only one. Two professors thought about these differences too and they came up with a cool theory.

Prof. Simcha Lev-Yadun of the Department of Science Education at the University of Haifa-Oranim in Israel and Prof. Jarmo Holopainen of the University of Kuopio in Finland had their work published in New Phytologist.

Stepping Back In Time

Red leaves in America serve as a warning flag to ward off insects. But in Europe, none of these evolutionary 'tricks' are needed, which means leaves are yellow.

To find out more, we have to step back 35 million years to sort out the mystery. Up until that time, huge areas of the globe were rich in evergreen forests. Then, a bunch of ice ages and dry spells came into the picture. Lots of the tree species evolved to become deciduous – meaning they lose their leaves depending on the season. Some trees even started to produce red leaves to keep the pesky insects away. But, something else came into play and you might be surprised to learn just what it was!

Look To The Mountains

It’s true. We have to check out the orientation of the mountains to get the scoop on why the leaves evolved to be red in America but yellow in Europe. In North America, north-to-south mountain chains created a protected area, enabling the plants and animals to migrate south or north. Joining them were the insects. So, the leaves in America remained red to continue warding off these annoying bugs.

But in Europe, the mountains are oriented from east-to-west, leaving no protected areas as the ice and other environmental conditions came to visit. Loads of the tree species just couldn’t survive the extreme cold. When they died, so did those insects that needed the trees for their survival. By the time the ice ages were over, those trees that had managed to survive didn’t have to deal with the now-extinct insects. So, no need for red leaves to keep them away!

Curious Minds Want To Know

I asked Simcha Lev-Yadun how he ended up studying leaves. While my background is in the life sciences (medicine and nutrition), I always wonder how people end up in the many different, neat areas of science. He explained:

I wanted to be a biologist and archaeologist since I was ten years old. For me, science is a lifestyle, not a job. At the age of 57…I look backwards and see that I made the right decision.

He also shared his plans to meet up in Scandinavia with his colleague Jarmo Holopainen, where they hope to find out even more about why plants have such cool and different colors.

My Wishful Thinking

While my dog Tiko probably doesn’t care much about leaf color when he dashes through the crisp autumn leaves, I like to understand what makes one leaf a bright yellow and another a brilliant red. Now, if only leaves could somehow evolve to become fluorescent pink, my favorite color. Somehow though, I just don’t see it happening!

The Recipe For A Perfectly Sticky Web May 31, 2009

Posted by Mrs Weird Scientist in Animals, Brain Power, Evolution, Insects, Tough Stuff.
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Have you ever tried to bake a cake, only to find out that when it came out of the oven, it was dry and hard? Maybe you realized that you’d put in too much sugar. Or, maybe you cooked it for too long. Would you believe that spiders have a similar challenge when it comes to spinning their webs? Too much of a good thing can actually leave a web that’s far from perfect.

For this web to catch its prey, it needs to have just the right amount of stickiness and strength.  If all goes well for the spider, dinner will soon be served!

For this web to catch its prey, it needs to have just the right amount of stickiness and strength. If all goes well for the spider, dinner will soon be served!

For a spider to catch its prey, the web needs to be sticky but still remain strong. If the balance isn’t right, the web won’t catch a bug and it’ll be one hungry and grumpy spider!

A Killer Web Evolves

If you’re a spider, you’ve got your work cut out for you! To catch your prey, you want a web sticky enough that the bug gets caught inside but strong enough that the web doesn’t break from its struggles. With such a fine balance needed, spiders have evolved to get it just right.

Let the Construction Work Begin

To build those impressive webs we see, spiders start by putting down lines of dry silk. Then, they weave spirals of sticky silk to nab their prey. But, spiders of yesteryear didn’t build their webs in quite the same way.

Millions of years ago, spiders would lay down a coating of dry adhesive on these spirals. Rather than stick to the web, a bug would be entangled by these dry spirals. As a cool fact you can throw out at your friends, there are still some spiders today that weave their webs with this dry adhesive – we call them deinopoid spiders.

Yet things began to change, with orb weaving spiders evolving to make webs that were more effective at catching prey. Rather than continue to use this dry adhesive, spiders started to go the sticky route by using wet drops of a glue-like substance. When you think of glue, it seems that the sticker the glue, the better. Not for spiders though!

Curious Scientists Start Investigating

Some scientists started to wonder about these sticky webs – is stickier always better? To find out, Ingi Agnarsson of the University of Puerto Rico in San Juan and Todd Blackledge of the University of Akron in Ohio went on a mission to check out a lot of different spiders. They observed 17 species of orb weaving spiders. You’d have to like spiders quite a bit to watch so many different kinds! The full study results are in the Journal of Zoology.

It’s All About Force

The researchers tested the strength of the strands and the stickiness of them too. How’d they do that? Well, they stuck a piece of sandpaper in the web and then measured how much force was required to remove it.

To break a strand on the web, a specific amount of force is needed. When the researchers put the web to the test, they found that by using anywhere from 20% to 70% of this force needed to break the web, the sandpaper was released.

So, a stickier web might hold the insect but as it continues to struggle, the force would ultimately break strands of the web, causing the insect to be released. Yet, with the glue being a bit less sticky, the insect could pull away from a single strand, but it would get caught by the next one. Since the strands don’t break, they can continue to stick to the bug, making its fight a much harder one.

Spiders Are Impressive

It’s actually really impressive and cool when you think about the work that goes into creating a web with just the right balance of stickiness and strength. As for me, I’ll leave the bug-catching to those smart spiders. I think I’ll just stick to making cakes instead. Pun fully intended! Now if only there was a recipe for making good jokes…

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Secrets Of Climbing June 1, 2008

Posted by Mrs Weird Scientist in Animals, Environment, Evolution, Think About It.
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Treetops

Ever had a favorite tree in your yard that you liked to climb once in a while? You probably scurried up the tree and maybe hung out for a bit before carefully making your way down to your abode on the ground. We all know that some creatures like to live up in the trees but what makes the trees such a cool place to inhabit? Scientists may have found some clues as to why early primates liked to make their home in the forest canopy. It’s all about size!

Apes and monkeys – ancestors of humans – might have ended up in the trees because of their small size. Researchers have been curious for a while now about why early primates happily lived up in the trees. Why so curious? It’s because they thought that climbing used up more energy than walking. When it comes to walking, for example, smaller animals use up more energy in comparison with larger animals. Generally, we would expect the animals to live in a way that conserves energy. So, it has been somewhat of a confusing question as to why primates would make a transition to the trees if it meant that their energy efficiency was compromised.

Using A Treadmill To Investigate

Mongoose Lemur

You’re probably reading the word ‘treadmill,’ and wondering to yourself what I’m talking about! Well, treadmills can be useful for many things – not just for us humans to use as exercise equipment. In this case, researchers from Duke University in North Carolina observed primates as they walked and climbed on a special treadmill that was designed for the study. The results were surprising!

The researchers found that there was no difference in how much energy was consumed for small primates whether they walked or climbed the treadmill. This means that climbing didn’t have a higher energy consumption. In this way, the small primates could make good use of the treetop environment without compromising their energy. These early primates would have been approximately the size of a very big rat. The results were published in the journal Science and the information gives us some clues about how the ancestors of these primates ended up in the trees approximately 65 million years ago.

Yummy Food

You might be wondering what was so great about the trees? Well for early primates, moving into this new environment provided them with an abundance of tasty insects and fruits. On top of that, evolutionary changes then occurred, which means that the primates developed characteristics to help them better adapt to this new environment. For these mammals, the changes included the development of nails instead of claws. Jandy Hanna, a Duke graduate student at the time of the study, created the treadmill apparatus and measured primate activity and energy consumption. She explained:

We assumed it would be more energetically expensive for all of them to climb than to walk, so this finding was unexpected. What we have shown is that they could have made this shift into a rich environment with insects and fruits without increased energetic cost.

Ultimately, the small size of the primates meant that they could make the transition into the trees to enjoy the goodies up there. From the perspective of energy consumption, heavier animals had less incentive to climb than walk, so it was the smaller primates who had the competitive edge. Still, even if it does take more energy for humans to climb – that sure never stopped me when I was a kid and I liked climbing the tree to my playhouse.

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