Tag Archives: survival

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

Life on Mars? – The Key to Survival on The Red Planet

Science is all the rage in the film industry these days, with films like Interstellar proving to be massive hits both critically and in the box office.  Consequently, The Martian is hoping to capitalize on that success. This science fiction adventure is based on a best-selling book written by Andy Weir and features Matt Damon as Mark Watney, a botanist turned astronaut who finds himself stranded on Mars after an intense dust storm forces his crew to evacuate the planet. The film follows his quest to survive alone on a barren wasteland and his attempts to contact Earth and seek rescue.

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Credit: 20th Century Fox

While scientifically feasible and chock full of technical jargon, The Martian is a fictional story by all accounts. After all, humans can’t be expected to grow potatoes inside a tiny habitat for long term survival, as Mark Watney does in the film. But is life on Mars a reachable short term goal? At least one team of researchers thinks so, and they believe they have unearthed the key.

Cyanobacteria By Doc. RNDr. Josef Reischig, CSc. (Author's archive) [CC BY-SA 3.0 (http://creativecommons.org/licenses/by-sa/3.0)], via Wikimedia Commons

By Doc. RNDr. Josef Reischig, CSc. (Author’s archive) [CC BY-SA 3.0 (http://creativecommons.org/licenses/by-sa/3.0)], via Wikimedia Commons

Astrobiologist Cyprien Verseux and his team at NASA’s Ames Research Center have discovered a way to use cyanobacteria in order to sustain a long-term human presence on Mars, which was previously thought to be unrealistic due to the amount of resources that would have to be sent.

The idea of cyanobacteria in outer space research is not new. Humans have already been using microbes to search for life on Mars, as illustrated in the video below:

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Credit: Open University

Cyanobacteria not only have the ability to survive and grow in Mars simulated conditions, as determined in a study by Karen Olsson-Francis, but they can also fix carbon from carbon dioxide (CO2) and create useful nitrate from dinitrogen (N2), which Mars has plenty of in its atmosphere. While we can’t actually survive simply off of eating cyanobacteria due to their lack of vitamin C and overabundance of vitamin A, they can be used to feed microorganisms, which can then be utilized to convert biomass into potentially fertile soil. Aquaculture is also a possibility, as crustaceans and shellfish are already feeding off of cyanobacteria as a main food source.

Furthermore, Verseux also explored the prospect of using cyanobacteria to produce oxygen, finding them to be even more efficient producers than fully grown trees. Cyanobacteria were even able to produce components of biofuel that could be used to power vehicles and equipment as illustrated in a study by Daniel Ducat; however, further advances must be made for either of these applications to come to fruition.

Often times we watch these ambitious science fiction movies thinking that they’re simply the pipe dream of an idealistic filmmaker. But just as screenwriters are dreaming up new frontiers to impress and amaze audiences, scientists are working diligently in the background to make those frontiers a reality.

To infinity and beyond!

Mars Exploration Rover By NASA/JPL/Cornell University, Maas Digital LLC [Public domain], via Wikimedia Commons

Mars Exploration Rover
By NASA/JPL/Cornell University, Maas Digital LLC [Public domain], via Wikimedia Commons

 Tim Cheung