21 Aug 2015

What Goes Around Comes Around - Undersea Carousel Style!

Photo: http://www.seaglasscarousel.nyc/the-seaglass-story/ 

Post by Helaine Becker

A fantastic new carousel  called Seaglass opened in New York City yesterday. According to Show Canada, the group that fabricated the structure, "visitors find themselves within a musical seashell structure of 30 illuminated fish of different changing sparkling colors and species." 

The fish are up to 4.5 m tall, made of translucent fibreglass "reminiscent of frosted colored pebbles of sea glass." They rise, fall and swirl about in invisible 'currents' much like real fish do in the ocean.  (See a video of the carousel in operation here) It looks totally spectacular, and I can't wait to get to New York so I can ride it myself!
Photo: http://www.seaglasscarousel.nyc/the-seaglass-story/ 
My friend Stephen Sywak was part of the engineering team (McLaren Engineering Group) that helped make the carousel come to life. He has very kindly answered my questions about the engineering challenges involved in making this complicated and gorgeous work of art. This is what he told me, in short:

Can you describe the carousel for me?
It's a multi-axis carousel.  There's a main turntable, but within the main turntable are three smaller turntables.  And on THOSE turntables, there are a number of "fish," like the horses on an old-timey carousel, except for a few things....

Photo: http://www.seaglasscarousel.nyc/the-seaglass-story/ 
* You ride INSIDE the fish, not on top of them
* The post that the fish move up and down on only goes BELOW the fish.  On a carousel horse, it goes THROUGH the horse, from the floor to the canopy.  Structurally, and  from a control point  of view, it's a lot harder to do it THIS way.
* The fish not only move round on the large carousel, but they swing back and forth because of the smaller carousel.  And then they swing back and forth AGAIN, on their own poles.  AND they move up and down on their own poles (There are a few fish on  the MAIN carousel that only move a little or not all; some of these are designed to accommodate wheelchairs.).

So how do you make it all go "swish?" 

The main carousel and the smaller carousels are driven by industrial motors.  The motors run gearboxes, and the gearboxes run "ring bearings" (large, geared bearings--like you would see on a tank turret).  They provide about 20-30 HP for the main carousel, and 8-10 HP each for the small ones.

The fish are mounted to custom hydraulic cylinders.  But we didn't use hydraulics to run them up and down.  The hydraulic cylinders are perfect for guiding and positioning the rods beneath the fish, and holding them stable.  They are designed to handle linear and rotary motion.  Why reinvent, when it's cheaper to buy an existing product?  (That was my idea, by the way!)  Instead, we used two standard electrical motors (and gearboxes) to do the local lifting and the local turning. 

If I recall correctly,  a giant "slip ring" at the center of the table brings in all the power and control signals.  It allows the central turntable to rotate round and round without winding up a bunch of cables.  The inner (smaller) turntables, and the fish themselves, only spin partially around.  We used "Cable Chains" to bring power and signal to them.

We used industrial control systems both for safety, and to allow us to simplify and reduce the number of signals crossing the main, central slip ring.  Basically, it's running on a network, like computers in an office, or a network you might have at home.  But it's got layers of security on it, so that it can't be "hacked."

I never ever considered the possibility that someone would hack a merry-go-round. Go figure. 


What were the key challenges in  taking this idea from the drawing board to Battery Park?

One key challenge was was that we had to work very closely with the artists to make sure that we could implement their vision.  There were a few occasions where the "artist" types even took their lead from our designers and engineers! 

On the physical side, there was the fact that the structure on which the Carousel's turntables sit is all below ground. It's about 8-10 feet "tall," but it's all under foot!   

Photo: http://www.seaglasscarousel.nyc/the-seaglass-story/ 
We also had to make sure that all the various motions of the fish (large turntable, small turntable, fish "wag" and fish "heave" up and down) didn't make the riders heave their respective breakfasts and lunches. 

Thanks for that image. What's your next coolio project?

I'm currently working on a test set-up for an actuator (motor, gears, sensors, etc.) that rotates the solar arrays  on geo-synchronous satellites. If it turns out I know what I'm doing, then I hope I get to work on some of the actuator designs for the next Curiosity mission, slated for 2020.   

WOW! From undersea to outer space! An engineer's life is full of thrills! But now the most important question of all: Do you get to ride on the Seaglass Carousel for free?

Unfortunately, no.  But it's only $5!

Ok then. I'll book my ticket to New York and get in line. 

14 Aug 2015

Citizen Scientists Sampling Seawater Radiation

By Paula Johanson

If you've ever worried whether radiation from Fukushima after the tsunami in 2011 might be washing up in the ocean along Canada's west coast, there is a website for you at Fukushima inFORM. And the news is good!

There are trained scientists monitoring seawater samples from offshore, and test samples from marine life. They're working together with the Department of Fisheries and Oceans, and with Health Canada. As well, citizen scientists assist with collecting water samples at several places along the shoreline. The samples are processed by the Fukushima inFORM team of scientists at the University of Victoria, and their partners across Canada and the USA.

Regular updates from Fukushima inFORM show that they are looking for two radioactive elements in particular, Cesium 134 and Cesium 137. Their test results so far show that while they are able to find in the samples small traces of Cesium 137 radiation from Chernobyl and from the nuclear testing in the 1950s and 1960s, they are not finding any from Fukushima. Also, they are not finding any Cesium 134 radiation from Fukushima, which has a much shorter half-life than 137. This is very good news.

Citizen scientists are a valuable part of the sampling process. These ordinary people are trained by a scientist to gather seawater samples for testing. Many of these people bring their friends or grandchildren along when collecting seawater samples. It's a good way to be part of the process of monitoring our environment!

7 Aug 2015

Chimeras, Heterochromatism, and Halfsider Parakeets

by L. E. Carmichael

Cool bird, right? I did some research on chimerism while working on Fuzzy Forensics and Forensic Science: In Pursuit of Justice. A couple of different kinds have been found in humans. The type described in the video, where two embryos with different sets of DNA merge during early development, is thought to be the rarest. There's not a lot of data on chimeras in humans (and even less in animals), because the condition is undetectable unless it causes health problems... or, as in the CSI episode Bloodlines (S4E23), a criminal's blood and hair have different sets of chromosomes. Every forensic scientist's nightmare!

Coming back to the birds, though, there may be another explanation. I haven't done any research, so this is pure speculation. But the process of going from a single-celled embryo to a fully-formed animal with billions of cells involves (surprise!) cell division, the process whereby one cell produces two daughter cells. Each daughter cell has to have a complete set of DNA, meaning the chromosomes get copied billions of times. Occasionally, the copying machinery makes a mistake, and a gene mutates during development. Every cell that descends from that cell carries the mutation. In many cases, the mutation has no effect on the cell or its characteristics. But in other cases, the change in the DNA causes a detectable change - like the cell's colour. The most familiar example of this is heterochromatic eyes - one eye of each colour, or one eye with multiple colours, like one of my family's sheltie Deacon used to have.

Puppy Deacon - his eye was half blue, half brown

Sometimes, the mutation happens in a gene that's involved in cell determination - a gene that helps tell the cell whether it's going to be a liver cell or a lung cell or a hair cell. Or, in the case of this totally awesome tulip that grew in my yard one year, a leaf or a petal!

The same bulb produced an ordinary tulip the following year.  That's how you can tell that the mutation was not in the original "embryo," but happened during the plant's development.

Stuff like this is one of the reasons I spent 11 years in university studying genetics. DNA is just SO darn cool.

Thanks to Paula Morrow for the video! And for more about chimeras, check out one of my books on forensics.

30 Jul 2015

Canadian Biodiversity Facility

This week while volunteering as a naturalist in Elk/Beaver Lake Nature Centre, I met a family that is having a Puffin Summer. Every day they go to Puffin Cam and then look up a new fact about puffins on the internet.

It used to be that you had to go to the library and find a book in order to learn about nature. How else could you identify what kind of butterfly you saw or what plant is growing behind your grandparents' woodshed? Now there are terrific online resources for people who love learning about the biological sciences! Of particular interest to Canadians is the Canadian Biodiversity Information Facility. The CBIF operates in support of the Global Biodiversity Facility, which has information on over a million and a half species.

Are you trying to find information on sapsuckers or ladyslippers, or other animals and plants? The CBIF is working to improve access to data on living things of interest to Canadians. On their website there are three tools to help users find the information they need:
  • Integrated Taxonomic Information System (ITIS) is a catalogue of common and scientific names and their synonyms that will eventually include all species found in Canada, the United States and Mexico. I clicked on Search ITIS, then entered the common name "oystercatcher" into their simple form, and it came up with links to pages on many kinds of oystercatcher birds, and the scientific names for each kind. Here's a photo of this striking bird, with its bright eyes and bill and pink feet.

"Black Oystercatcher HMB RWD4" by DickDaniels (http://carolinabirds.org/) - Own work. Licensed under CC BY-SA 3.0 via Wikimedia Commons - https://commons.wikimedia.org/wiki/File:Black_Oystercatcher_HMB_RWD4.jpg#/media/File:Black_Oystercatcher_HMB_RWD4.jpg

For the other two tools, you'll need the species name for the living thing you want to find.
  • Species Access Network is the Canadian component of a global project to provide Internet access to information associated with the billions of specimens housed in the world's natural history collections.Users can search these collections by species name, source collection, collector, or location.
  • Species Bank includes a collection of electronic resources that provide detailed information to support the identification of Canadian species including descriptive information, photographs, distribution maps, and more.

Now that it's summer, I hope you'll enjoy being out in the wide world, finding plants and animals in towns and in wild places. When you come back indoors, the CBIF website is a good place to learn about what you've found -- but no computer can substitute for breathing the same air as our animal and plant neighbours.

24 Jul 2015

Longing for the Giants

By Claire Eamer

In the long and complex story of evolution, organisms emerge and then disappear, never to be seen again. I understand and accept that. Honest. But, fair or not, I regret the loss of some organisms more than others.

I admit it. I miss giant ground sloths.

Don’t get me wrong. I’m not old enough to have met a giant ground sloth face to face. None of us is. The last lingering remnants of a great bunch of animals perished about 5,000 years ago, probably on a small Caribbean island.

Fossil foot of a Jefferson's ground sloth beside my shoe. C. Eamer photo.

While they were here, though, they were amazing. And really, really big. Well, some of them were big. Some species were as small as house-cats, but the largest ground sloths – Megatherium and Eremotherium – were the size of elephants. Hairy elephants, with thick hides dotted with bony plates, claws the size of bananas, and a propensity to stand up on their hind legs and maul substantial trees.

If it’s any comfort, they were vegetarian. Mostly. Some scientists think that Megatherium, at least, might have used those giant claws to grab a bite of meat to go with the veggies, especially when climate change dried the local landscape and thinned out the forests it relied on.

Greg McDonald, senior curator of natural history for the US National Park Service, is another sloth enthusiast. He recently delivered a talk on ground sloths, via Skype, to an appreciative audience in Whitehorse, Yukon.

The Yukon is, surprisingly, ground sloth territory. It’s actually where I first met a ground sloth – if not face to face, then at least face to skull. It was a Jefferson ground sloth, a member of the genus Megalonyx, and its ox-sized skeleton looms over visitors to the Beringia Interpretive Centre in Whitehorse.

For hundreds of thousands of years, Megalonyx ranged from southern Mexico to as far as Alaska and the northern Yukon. Megalonyx was unique, McDonald said, in being a wholly North American sloth. Although its ancestors came from South America, Megalonyx itself evolved in North America and never spread south of Mexico.
A sloth skeleton towers over visitors to the Beringia Interpretive Centre. C. Eamer photo.

That made it a late-comer in the sloth world. Like many other strange and wonderful mammals, sloths evolved in South America, in splendid isolation.

“For most of the age of mammals,” said McDonald, “South America was an island continent, much as we think of Australia today.”

The giant Megatherium roamed the ancient forests of South America in those days. And it had a curious assortment of cousins: anteaters, giant armadillos, and a bizarre creature called a glyptodont that looked like an ambulatory bone igloo. They all belonged to a group called Xenarthrans, which evolved exclusively in South America.

Once thought to be an odd evolutionary offshoot, Xenarthrans are now recognized as one of the major subdivisions in mammalian evolution, McDonald said. They prospered for tens of millions of years in South America and moved on to North America when the Isthmus of Panama began to form and link the two continents, just a few million years ago. (Or maybe more than a few million years ago, according to some recent studies.)

That was a momentous time in evolution, said McDonald. It’s called GABI: the Great American Biotic Interchange. Released from isolation, the Xenarthrans drifted northward, along with other distinctly South American animals, such as giant flightless birds with the hooked beaks of meat-eaters and the ancestor of the humble porcupine. At the same time, animals that had evolved in North America moved southward, including hunting cats with dagger-like fangs and those members of the camel family that became South America’s llamas and alpacas.

Ground sloths spread and adapted and changed on both continents for several more millions of years. They even took to the sea. Marine deposits in southern Peru have turned up a wealth of ancient fossil whales, seals, and sea lions – and entire skeletons of giant sloths. The sloth skeletons show clear evidence of adaptation to an aquatic environment. McDonald said it appears that the aquatic sloths were evolving into animals that went into the sea to eat sea grasses. Like the whales, they were reversing the classic sea-to-land journey of most mammals.

But that’s as far as they got. The aquatic sloths died out about 4 million years ago, and most of the rest of the ground
sloths didn’t survive the great megafauna die-off at the end of the last glaciation, about 12,000 years ago. A few small ground sloths lingered on isolated Caribbean islands, where 5,000-year-old sloth bones have been found in caves.

Today, the much-diminished sloth tribe has been reduced to the endangered tree sloths – a mere six species in two genera – eking out an existence in the shrinking rainforests of South and Central America.

The giants are gone. And, even though I never shared the world with them, I miss them. In fact, they inspired me to write my first kids' science book, Super Crocs & Monster Wings: Modern Animals' Ancient Past.

18 Jul 2015

Learn Latin Names of Common Plants

By Helen Mason

A recent trip to Ireland reinforced for me the importance of learning Latin names of common plants.

Of course I recognized my old friend Taraxacum sighted here at Mellifont Abbey in County Louth — and in numerous fields. Although we in North America don't think of dandelions as an invasive species, they are native to Eurasia and have been spread around the world by settlers who likely planted the seeds to make use of the plant's many medicinal and nutritional uses.

Dandelion at Mellifont Abbey. (Helen Mason photo)

I also knew that this bird fishing in the waters outside Ashford Castle in County Mayo had to be a member of the heron family. It's a grey heron (Ardea cinerea), a species native to temperate parts of Europe, Asia, and parts of Africa.

The herons around my Georgian Bay cottage are great blue herons (Ardea herodias) — same genus, different species.

Grey heron fishing in County Mayo. (Helen Mason photo)

What puzzled me, however, was a flower I found while exploring County Clare's Craggaunowen, a tourist site with re-creations of the various types of housing used in Ireland's past — from a Crannog or lake-dwelling from the Bronze age, to a ring fort from the 4th and 5th Centuries, to 1400s-era castle.

Walking through the woodlands below the fort, I admired this blossom.

The Irish jack in the pulpit: Arum maculatum. (Helen Mason photo)

Not recognizing it, but thinking it might be related to something I did, I asked the guide.

"Jack in the pulpit," she responded, "sometimes called lords-and-ladies."

This is where common names can run us into trouble. To me, a jack in the pulpit is a shy blossom that covers is reproductive parts.

The Canadian jack in the pulpit: Arisaema triphyllum. (Helen Mason photo)

In fact, these two jack in the pulpits belong to the same family but not the same genus or species.

The Irish plant is Arum maculatum, a woodland species common to Europe, Turkey, and the Caucasus. Like many plants, it has a number of common names — snakeshead, adder's root, Adam and Eve, and lords-and-ladies, as well as jack in the pulpit.

The Canadian plant is Arisaema triphyllum, a native of moist eastern North American woodlands. Like its Irish distant relative, this jack in the pulpit has other names, including bog onion, brown dragon, Indian turnip, and American wake robin.

Common names change from locale to locale. They can provide interesting information about the use of the plant or the social history of the namer. The Latin term is unique. It identifies one genus and species, and only that one.

10 Jul 2015

The Best Dog-gone Study Ever!

free vector Cartoon Dog clip artPost by Helaine Becker

Do you love dogs?

Of course you do.

How 'bout science?

Yes,  you love science too.

Then you will double-dog love this new Citizen Science project that you - and your dog - can participate in!

It's easy - all you have to do is wait for your dog to poop. Then stoop, scoop - and mail that poop to Oregon State University.
Yes, you read that right.

Researchers at the university would be most grateful if you mailed samples of your pet's poo to them for a study on dog microbiomes. They want to find out what's going on inside dogs' guts, and what mini-critters live in there. And the best way to figure it out is by looking at pooches' poo under the microscope. Lots of poo.

So go, ahead, stoop for science! You can find all the deets  on how you and your dog can enroll here.

Not a fan of 'pooping a letter' in the mailbox?  You can still participate in great dog-related science investigations. You'll find many other research studies, some as easy as answering a dog-related quiz, at the Dog Science Group.

<a href="http://cliparts.co/clipart/2939649">cliparts.co</a>