Stress & Survival: Birds Hanging in the Balance

As university students, we spend plenty of time trying to manage our stress levels when dealing with a plethora of assignments, projects, and exams. Stress has proven to affect the academic performance of students, but did you know that it may be the key to survival for birds in ever changing climactic conditions?

Biologist Roslyn Dakin and a team of researchers recently published a study with one goal in mind – to determine how stress affects the survival of baby tree swallows.

Tree Swallow | By Peter Wilton (Tree Swallow Uploaded by Magnus Manske) [CC BY 2.0 (http://creativecommons.org/licenses/by/2.0)], via Wikimedia Commons

 In order to manipulate the stress levels of the swallows, Dakin implanted corticosterone pellets into their bloodstream. Corticosterone, a stress hormone, has been shown to impact how often a mother would feed their offspring. Therefore, experimenting with its levels should affect survival.

So what exactly did Dakin find? Their results were seriously disturbed by exceptionally cold and wet weather, the ramifications of which are discussed in the podcast below:

The study revealed some extremely complex relationships between stress, weather, parental investment, and ultimately, survival. An increase in corticosterone did not necessarily lead to an decrease in mortality, as predicted. In fact, the offspring of mothers with higher corticosterone levels showed an increased risk of failure. In inclement weather, however, all individuals had a high likelihood of mortality.

One fascinating finding involved the relationship between the male and female parents. As expected, with  high female feeding rates, the offspring were more likely to survive. However, high male feeding rates combined with corticosterone-implanted females resulted in a higher risk of failure compared to females without the implants. Why is this the case? Wouldn’t more care from a parent allow for better survival? Several hypotheses were proposed. Highly invested males may be more sensitive to changes in their partner. As well, the female may be more likely to abandon their offspring if they feel that the male could care for the offspring on their own.

Field site at the Queen’s University Biological Station, Ontario | Credit: Adam Lendvai

More questions were raised than answered in the study, and unfortunately swallow populations continue to dwindle in Ontario, where the experiment took place. Clearly, any solution proposed will have a variety of factors at play. Nonetheless, we valiantly attempted to tackle the issue of declining bird populations in unpredictable weather – check out our video below for more!

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Tim Cheung, Peggy Hung, Kamyar Kazemiashtiani, & Josephina Kim

Terminating Species for the Greater Good

Have you ever wished for an annoying species to disappear off the face of the Earth? Do some species seem to exist just to cause misery for the rest of the animals on this planet?

If you answered “yes” to any of the questions above then you are in luck! Humans have invented a clever way to get rid of pest populations. It is called the Sterile Insect Technique (SIT). This technique has existed since the 1950s and was pioneered by Dr. R.C. Bushland and Dr. E.F. Knipling. As you can tell from the diagram below, the concept of this technique is very simple. Basically, nuclear radiation is used to make the male species of the pest you are targeting infertile. Then these males are released into the wild. The wild females cannot detect that the males are infertile so they will still mate with each other. After mating, the females will lay their eggs but the eggs will never hatch because of the mutations the radiation causes.

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The Sterile Insect Technique (SIT) involves releasing sterile males into the wild. The sterile males can still mate but no eggs will be fertilized. Credit: igtrcn.org

Here is a video that does an amazing job of introducing SIT.

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Credit: FAOVideo

You may be wondering if humans should be playing God but SIT is currently safer than using conventional means such as pesticides. With pesticides, it is not just the pests that suffer but everyone else. Helpful bugs such as butterflies and ladybugs can be harmed. Pesticides also ruin the environment by contaminating soil, water, air, and non-target plants. Even you can be harmed since pesticides easily stick to food products and are hard to get rid of. It is estimated that one million people worldwide per year die from pesticide-related causes.

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SIT is safer compared to pesticide use. Credit: Wikimedia Commons

Another reason the Sterile Insect Technique is beneficial is that it can exterminate pests that can’t be targeted by pesticides. These pests torment livestock and humans. The first species that was experimented on using SIT was Cochliomyia hominivorax, a parasitic fly known as the screwworm fly. Unlike normal parasitic maggots which eat dead flesh, screwworm maggots only eat the living flesh of warm-blooded animals. If you’re wondering why the flies are called screwworms, that’s because if the maggots are disturbed, they will “screw” themselves deeper into the flesh. This causes severe injuries and death in livestock. Thankfully, the U.S. has managed to officially eradicate this nightmare in 1982 using SIT.

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The adult form of the screwworm fly. Credit: Wikimedia Commons

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The larva form of the screwworm fly. A wound can contain hundreds of larvae. Credit: USDA

Although this technique is very effective and safe, there are still limitations such as being expensive and requiring high levels of training and security. In the future, as technology improves, Sterile Insect Technique may become reliable enough to replace pesticides.

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A modern-day example of STI being used to eradicate mosquitoes. Credit: TheLipTV2

 

-Bowen Zhao

New Material Stores Oxygen for Later Use

Oxygen is an important element required for metabolisms occurring in our body and without it we would be dead in a couple of seconds. This is the reason that we cannot survive under the water or any other place without oxygen. Scientists  at University of Southern Denmark found a new way to store oxygen for using in places that oxygen is not available. They made a substance based on cobalt which can absorb oxygen from its surrounding air or water and release it anytime it is needed.

By Kenneth Abbate , via Wikimedia Commons

Oxygen can bind many different materials but the result is not always useful. For instance, oxygen can spoil foods or can rust metals. Professor Christine McKenzie, one of the researchers, explains that this new material can reversibly react with oxygen which means it can be used to transport oxygen and release it in its initial form similar to what hemoglobin does in our body. Cobalt is responsible for determining the structure of this new material in a way that it has affinity for oxygen same as iron in our body. Professor McKenzie added that the rate of oxygen absorption can range from seconds to days because of several factors such as atmospheric oxygen content, temperature and pressure. Furthermore, the material releases oxygen when it is heated up or placed in a vacuum. This material can be used to make many useful devices. For example, a light weight device could be designed to provide oxygen for patients with lung diseases who have to carry heavy oxygen tanks with themselves all the time. In addition, divers can use this material to stay longer under the water since it can absorb oxygen from water if the diver breathes in all the available oxygen in the material.

By Stephan Borchert (Eigenes Werk.) via Wikimedia Commons

-Amir Jafarvand

The Benefits of Travelling

Last year I had the absolute privilege to spend a year abroad through the go global program at UBC.  I studied in Leiden, The Netherlands and spent much of my time exploring and travelling around continental Europe.  While travelling, I always thought about what I was doing and how it would compare if I were to stay at home.  I always wondered what the real point of travelling or being abroad was.  Turns out I’m not the only one who has been thinking about this and there is a wealth of research to suggest the benefits travel can provide.

The first benefit that may surprise most is ones overall health.  Many studies have compared those who travel often with those who do not finding that well travelled individuals are in an overall better health condition.  For example, a study by Chun-Chun Chen and James Petrick reviewed past literature on the overall health benefits of travel and found there to be a lower risk of diseases such as heart attacks.  They also found that stress levels were lower among those who travel which can help reduce many other complications.  It is also interesting to note that these health benefits were observed to gradually diminish after returning from a trip.

Video: TEDx Talks

The benefits of travel do not stop at ones health and wellbeing it can also extend to peoples work lives and overall career success.  This may seem counter intuitive since travel is often viewed as the opposite of work but many studies show that time off results in a more productive work ethic.  Lots of evidence points to the need to relax and clear your mind to be able to produce better work.  This is applied to many work offices at Google. Other studies also point to a correlation between university degree completion and higher incomes with those who travel more.

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Video: BBC

The last point I want to make is actually one I realized myself while being abroad.  I think it is one of the more important points.  Through my experiences in different countries and from simply reading the news its not hard to notice the many conflicts that exist between people around the world.  I noticed that those who remain isolated and out of touch from other countries and cultures have more negative thoughts and stereotypes towards others which often results in meaningless conflicts with big consequences.  Travel provides people with a real experience to which they can base their beliefs on and the ability to realize that we are all in the world together.  This can ultimately overcome many ideological differences and create a better understanding of one another pushing towards a more peaceful and meaningful population.

On immortality: a very human desire

If presented with the fountain of youth, would you drink?

People have entertained the idea of immortality across time. Greek mythology tells of the phoenix, a bird capable of rebirth. The prominence of comics as a publication medium early in the twentieth century gave rise to a slew of superheroes capable of super-regeneration and longevity, like Superman and Wolverine. Even Lord Voldemort [SPOILER: highlight to reveal] went through the trouble of creating seven horcruxes to secure a strong hold of the living realm. Why are we fascinated with the concept of immortality?

The motivation to discuss immortality is probably related to people’s natural aversion to death and aging. There are plenty of cosmetic products and procedures that generate a lot of revenue by reversing the effects of aging, such as Botox. But what if instead of merely combating the symptoms of aging, you could eliminate it completely?

Certain examples of non-aging exist in nature. Hydras have been observed to not age. While not quite immortal, lobsters have shown to not be strongly affected by age. What can we learn from these organisms?

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In DNA replication, DNA polymerase takes up a short space on the sequence that it doesn’t copy, like painting itself into the corner of a room. Image from ClipartHeaven.

At the ends of our DNA strands are sections called telomeres – repeats of nucleotides that prevent degradation of the gene as it replicates over time. Every time a cell divides, the telomeres get shorter. After many replications at a point called the Hayflick limit, the telomeres reach a critically short length and the cell stops dividing. In a way, telomere length is like a biological clock that can be used to determine lifespan.

Cells also produce an enzyme called telomerase, which adds nucleotide bases to the ends of telomeres. However, the rate of telomerases’ repair of the telomeres is overcome by the rate of cell division, so telomeres continue to grow shorter and the cell ages.

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Telomerase. Here, “senescence” means “old age”. Images from the National Institutes of Health.

So does the answer to immortality lie in telomerases? Not quite. High telomerase activity is detectable in more than 90% of malignant tumours. The action of telomerase can provide cells with the capacity to infinitely replicate – a defining factor of tumour cells.

So where does this bring us? We aren’t any closer to living forever, but average life expectancy has risen over time, owing to advancing medicine and lower infant mortality rates. Still, it is just as interesting to ponder how one might spend lottery winnings as it is amusing to think about what one would do with unlimited time. Perhaps the search shouldn’t be for biological immortality, but to leave an immortal legacy. As A. A. Milne had said, “I suppose that every one of us hopes secretly for immortality; to leave… a name behind him which will live forever in this world.”

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“Life Expectancy at Birth by Region 1950-2050” by Rcragun from Wikipedia.

– Trevor Tsang