Scientific Scribbles

The voice of UniMelb Science Communication students

Signs of Spring

 

If you go into the bush today, you’re in for a wonderful surprise. Our National Parks and Reserves are currently putting on spectacular spring display. A multitude of stories await discovery by those who care to seek them out. 

 

It’s mid-October and the spring is well underway. The days are getting warmer and the evenings longer. Bees are abuzz, gardens are in full bloom and if you tend to a veggie patch you may even be enjoying your own snow peas by now. Spring is a period of great activity in the natural world. As such it is the perfect time to observe what is happening in your local bushland reserve.

Wildflowers

Winter rains set the stage for what’s to come. Should rain be plentiful, so too shall wildflowers. Should rain be scarce, wildflowers shall also be. This year’s display contrasts starkly with that of the 2016 season, when a wet winter brought about a purple haze of Chocolate Lilies, hovering just above the forest floor.  This year winter was relatively dry and as such far fewer wildflowers choose to bloom. Nevertheless, a full palette of colour can be seen: Guinea Flowers with their profusion of bright yellow petals shine like beacons, Rice Flowers like patches of snow whilst a splattering Wedding Bells brighten the dull leaf litter.

Pink Bells (Tetratheca ciliata) could easily be overlooked due to their downward-facing flowers. NG

Delicate orchids arise from underground tubers. Like gems, they tend to be few and far between; a Leopard Orchid on a rocky rise, a Dwarf Greenhood in shaded depression. Before long these unusual flowers will shrivel in the heat and retreat to the soil once more. Even here they are not entirely safe though, as White-winged Choughs relish their starchy tubers and will unearth them if the opportunity arises.

A Leopard Orchid (Diuris pardina). Certainly a spectacular orchid! NG

 

The blooming of wildflowers follows a orderly and predicable procession. Early Nancy kicks-off the wildflower season (around August) and Blue Pincushions, amongst others, mark its close (around December). Everlasting Daises, with their tough, wilt-resistant bracts persist into January. Different wildflower communities and climatic zones occur throughout Victoria, of course, resulting in different displays and timing variations.

Blue Pincushions (Brunonia australis) with yellow Sticky Everlastings (Xerochrysum viscosum) in the background. NG

Birds

Just as the colourful wildflowers delight our visual senses so too does birdsong our audial senses. Rufous Whistlers – having recently arrived from warmer, northern clines – sing heartily throughout the day. The plaintive, falling call of the Horsfield’s Bronze Cuckoo can also be heard. His arrival marks the beginning of spring and for some unfortunate Blue Wrens and honeyeaters, a lot of hard work (as this wily bird chooses to deposit its eggs in another species nest, abandoning its parenting duties).

Later the Rainbow Bee-eaters and Sacred Kingfishers will arrive, having also migrated down from warmer, northern clines. These industrious birds excavate tunnels into eroded creek banks to form their nest (the latter sometimes also uses tree hollows).

A pair of Rainbow Bee-eater, male at left (with longer central tail-feathers). A welcomed spring visitor! Photo by Jim Bendon via Flickr

And then there is the background goings-on of the regular residents: Wood and Black Ducks with their large clutches of ducklings, Masked Lapwings and Magpies with their territorial swooping as they defend their nests and Grey Shrike-thrushes with their melodic tunes.

So don’t miss out on this marvellous show. Awaken your senses, channel your childlike curiosity and get out into nature to discover the myriad of wonders awaiting you.


Call of the Koel

A curious call has infiltrated Melbourne’s soundscape. From mid-October onwards, a loud and monotonous birdcall can be heard emanating from urban parks and gardens throughout our suburbs. Day and night the bird persists with its repetitive and ever-rising ‘song’:

‘koo-EL, koo-EL!, koo-EL!!, koo-EL!!!’

If you investigate further, and gaze up into the canopy, you may be able to glimpse a sighting of the songster: a black bird (a little smaller than a Raven) with startlingly red eyes and a slight metallic sheen to its plumage. He is an Eastern Koel – a species of migratory cuckoo – and he is singing his name in the hope of attracting a mate, having flown all the way down from the tropics in order to do so.

Prior to 2000 the call of the Eastern Koel did not ‘grace’ our city. Indeed, Victoria as a whole has rarely hosted this species in the past, with historical occurrences being few and far between and descried as ‘accidental’ (on the bird’s behalf). Traditionally, south-eastern New South Wales was the southern-most extent of the Eastern Koel’s migration. In relatively recent years, however, Eastern Koels have been arriving in Melbourne in considerable numbers. So why the sudden change?

It’s a perplexing riddle, but the answer may lie in the way in which we have designed our cities.

Victoria has long been known as the ‘Garden State’ and Melbourne is renowned for its many parks and open spaces. In these greenspaces we have planted a vast array of non-local plants, including many species of tropical trees from northern Australia. The Moreton Bay Fig is a prime example of this. Favoured for its shady canopy and graceful form, it was planted in abundance during the 1800s. As such we now enjoy many mature trees of this grand species. The benefits of these plantings have extended beyond our own use and appreciation however, as the bountiful crop of figs which these trees produce on a yearly basis is of great benefit to our native urban wildlife. Grey-headed Flying Foxes, for instance, seek-out and consume the fruit of the Moreton Bay Fig with great enthusiasm. It is, in fact, a common sight to see their silhouettes gliding between city buildings as they navigate the urban jungle in search of fruiting trees.

The large leaves and broad canopy of the Moreton Bay Fig makes it an ideal shade tree for parks. Photo by Michael Coghlan via Flickr.

Like the Grey-headed Flying Fox, the Eastern Koel also enjoys feasting upon the fruit of the Moreton Bay Fig. Figs, in fact, constitute its primary food source. It seems, therefore, that through selecting our own urban flora we have unwittingly accommodated frugivorous (fruit-eating) fauna such as the Eastern Koel and Grey-headed Flying Fox. As such we have unintentionally extended the range of Eastern Koel and made the Grey-headed Flying Fox a (more-or-less) permanent resident of Melbourne [The latter naturally follows the flowering of eucalypts down the east coast of Australia to Melbourne. In ‘natural’ circumstances it would, however, move back up the coast when the flowering subsided].

It seems, whether we enjoy their repetitive call or not, that the Eastern Koels are here to stay. Their range extension provides an good example of the adaptability of nature and some hope for other species which may need to migrate away from their historic range in the face of climate change.

An Eastern Koel perched in the canopy of a fig tree. Photo by Brian Ralphs via Flickr

Premature Deaths

Why do Some people die before the average age of death?

 

           Sustainability poster – Air pollution (https://flic.kr/p/C2Nkze) by Kevin Dooley

Premature death has many causes. pollution, especially in the air, is considered as the most cause of premature death. It is to blame for one to six premature deaths in the poorest population around the world. Other causes of premature death are injuries and suicide.

In 2015, Air pollution causes more than half of the global deaths which are occurred in India and China. “The number of deaths is about 9 million people”, the commission reports. You will be surprised if you know that “three times as many deaths as [from] AIDS, tuberculosis and malaria combined and 15 times as many deaths as [from] war and all forms of violence ” the report says.

In fact, there isn’t enough research to correctly gauge the effects of certain chemicals. So, this number is an underestimate.

Even though pollution has a role in disease, the report estimates that exposure to dirty water, air, and soil puts a more than $4.6 trillion drain on the global economy.

Joel Kaufman, of the University of Washington School of Public Health in Seattle, believes that decisions made in the health will save others life for a long-term, not just for today.

The health costs are enormous. In 2010, the cost of pollution in China was about US$1.4 trillion, and in India about US$500 billion.

Governments across the world should do their efforts to stop this pollution. If they don’t, the rate of deaths will double by 2050.

 

What About Australia?

In 2010, the increased mortality from air pollution occurred largely in major urban areas such as Sydney and Melbourne while air pollution from natural sources affected large areas of Australia. Sources of fine particle pollution in our cities include wood fire heating in winter, traffic, power generation (transported from other areas), and industry.

In Australian cities, we have relatively low levels of air pollution compared with many of the world’s major urban areas. Air quality in Australia has improved over the past few decades and rarely exceeds the national air quality standards.

But this should not be a cause for complacency, as there is no accepted “safe” in air quality, even within the national standards, will have beneficial health effects for everyone.

 

What Can Be Done?

To stop the air pollution, we must have focused on a mix of technological solutions, regulations, and policies, and encouraging behavioral change.

Switching to clean power sources such as wind power, solar power, hydropower, will help to reduce causes of air pollution. We should do our efforts to save our lives.

 

 

 


Building brains – how close are we?

I recently finished watching the TV series on Netflix called Westworld. Yes, it came out in 2016, and yes, I was late on the bandwagon. But now I understand why there was so much hype about this Sci-Fi meets Wild West drama series.

Westworld Trailer

It’s set in the wild west somewhere in the foreseeable future, in a theme park called Westworld. Unlike Disneyland, every host there is actually a super high-tech android, that has been taught to think and feel the way that humans do. They all have intricate backstories and storylines to take guests on, like normal theme parks have different rides. It’s based on a film from 1973 of the same name.

Westworld is set in the Wild West – image by Mark Willocks via Flickr

 

The hosts were of spooky human-likeness, and the line separating humans and robots is often blurry. It’s impossible to watch something like this and not ask the question – is something like this really possible? Could scientists engineer “brains” that think the way that we do? And if it’s possible, where are we on that road to discovery?

This kind of science is being investigated, but we’re still a bit behind the knowledge we’d need before we can create a real Westworld. The current focus is mostly on understanding the human brain, and especially, how it can learn.

The learning curve

Learning is an extremely curious process, because it involves physical changes in the wiring of the brain. The cells of the brains are called neurons, and neurons are what pass messages around the brain and through the body. Think of them like streets that connect and branch to form a massive network map. Pathways that are often used become stronger; a phenomenon known as “neuroplasticity”.

There are numerical models that use binary numbers (0 and 1) to imitate the flow of signals through neurons, like traffic lights in the roadmap of neural pathways. But the brain doesn’t function in equations, the same way that streets are much more than just roads and traffic lights. The whole reason we have streets is to carry cars, the same way that the brain’s networks carry electrical currents. These currents are how the neurons talk to one another, by sending out an electrical pulse.

To really understand neural networks in the brain, we need a physical model: one that actually carries electrical impulses the way the brain does.

The silicon brain  

Karlheinz Meier, project co-ordinator of the BrainScaleS project, and his team are developing an artificial brain model in silicon. It’s like a really high-tech computer, but like a disc and jam-packed with brain-like processes.

Instead of executing a pre-programmed function like most computers, these models are progressively configured. It’s almost like they “learn” how to work.

As Meier put it, he’s developing “the first computer that does not compute”, rather a machine that actually learns the processes as it goes, the way the learning brain does. This means that the model will be effectively modelling neuroplasticity, as it configures it’s own function based on the input it receives.

Outsmarting ourselves

The advantage of these silicon models is that they are much faster than the brain. The neurons of the brain have a very low conductivity, but a high capacity. It’s like filling a large bucket of water (the capacity) with a tiny hose (the conductivity). Silicone has a much faster conductance than neurons, so it can process information, complete tasks and undergo changes similar to neuroplasticity in a much faster time frame.

Instead of trickling information through at the biological brain’s pace, these machines can catapult enormous quantities of information in a fraction of the time. As seen in Westworld, these machines could (maybe one day) be far smarter than us. Imagine what would that mean for society, if we create a superior being to ourselves! Or even a vessel to harvest our individual brains, and make us immortal…

 

04. Human and Robots

Who will win? – image by Muhammad Taufik via Flickr

 

Remember that Westworld was originally a film from the 1970’s, so these ideas of android takeover have been around for a while. It might be many years again before we see these kinds of technologies emerge.

Until then, these new silicon brain models could change the way scientists investigate the behaviour of neural networks, and help scientists better understand the biological brain to build artificial cognitive systems. Maybe these models are the key to unlocking what it takes to build a fully functioning human robot, or maybe they just help us build really fancy computers.


How do taste buds change?

When I was a kid I accidentally ate cat food.

Not the little crunchy kibbles, which, admittedly, sometimes smell kind of tasty. I’m talking about the cold, slimy, wet gruel, that’s so sludgy you need a spoon to extract it from the can.

I say it was an accident, because in one hand I had a spoonful of peanut butter that I was eating out of the jar (all class), and in the other, I used a spoon to scoop out the cat food. I forgot which hand held which spoon, and in a crucial moment, I was distracted and put the wrong spoon in my mouth. Expecting crunchy, peanut buttery goodness, I got a mouthful of only what I can describe as death and decay in a foul fluid/solid form.

I honestly think I blacked out from the shock and horror, but recalling the memory from over 15 years ago still makes me gag and shiver. Until recently, the smell of tinned fish made my eyes water and the hairs on the back of my neck stand up in repulsion.

I already feel queasy – image by Dario Lo Presti via Flickr

 

I always wondered, after all of these years, why does that one memory still haunt me?

Putty-brains

Memory and learning both start as signals carried through the cells in the brain, called neurons. Think of neurons like roads, and the cars travelling along them carry signals and information around the brain. At every intersection between neurons is what we call a synapse.

Now here’s where it gets interesting: synapses can actually rearrange themselves to favor pathways that get a lot of use. It’s like the council realizing that one particular road gets a lot of traffic, and either widening the road, or making the lights favor traffic along that particular route. This is called neuroplasticity, and is the reason things can become “second nature” – the synapses have rewired to make brain signaling more streamline and effortless.

Neuroplasticity is the reason we can learn to juggle, why blind people may have better hearing, and why human brains can lose up to 1 cell per second and still function – the brain rewires itself!

“Neurons that fire together, wire together” 

In my fishy case, what must have happened is that I lived the traumatic memory over and over so many times, I’d unwittingly strengthened the “fish = repulsion” pathway in my brain. The neurons that screamed “GET THIS OUT OF MY MOUTH” when I accidentally ate the cat food was associated with all things fishy: the smell of fish, the sight of fish and the thought of fish.

Snapper out of it

I’d accepted this as a lifelong disposition, until in the last few years I started getting really dry skin. One of the best ways to fix that is to increase the amount of healthy fats in my diet. And one of the best sources of these fats are, you guessed it, fish. Obviously, fish oil capsules were a no-go (fishy burps? I’ll pass), so I had to think of ways to sneakily overcome my aversion.

Fish oil capsules can leave you with fishy breath – no thanks! – image by Fitness Twistme via Flickr

 

Armed with trusty lemon juice and copious amounts of beetroot, I managed to disguise some pan-seared salmon in a salad. As the months went by, I learned to eat the salmon from the pan, and then one day, I cracked open a tin of salmon, and miraculously, I didn’t keel over retching.

This was neuroplasticity in the making – instead of associating fish with that traumatic episode, my brain had rewired to think of fish as healthy and nourishing.

Tastebuds (and brains) change

This is also why as a kid you might have sipped wine, been disgusted by it and sworn you could never find pleasure in such vile fluid. But after trying it again here and there, usually at festive events like parties or barbeques, you eventually started to like the taste. That’s the “happy-event” neurons firing with the “taste of wine” neurons, and slowly building a happy train of thought.

Whilst I don’t think I’ll ever want to train myself into liking anchovies, I wonder what else my brain has secret vendettas against, and if I could train myself out of them.

So what bad habit or association are you going to train yourself out of? Or have you done so already?

 


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