Tag Archives: animal behaviour

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The experiment has begun, and so the time has come to explain what it is exactly that I am attempting to accomplish over the course of the next two semesters. I have already stated my three hypotheses in a previous blog post, but here they are again… just in case they’ve slipped your mind!

Hypothesis 1: I Hypothesize that the visual modality is involved in conspecific interactions between pairs of red-backed salamanders and that it interacts with the olfactory modality.

Hypothesis 2: I hypothesize that olfactory cues or the visual cues contain information about the sexual identity of the competitor.

Hypothesis 3: I hypothesize that colour vision plays a role in salamander conspecific interactions.

Experiment 1

In order to support or disprove my hypotheses, I have come up with three experiments. This week, I started the first experiment, which addresses my first hypothesis. It is a cue isolation experiment, in which 40 salamanders (20 mature males and 20 juveniles) will undergo 4 separate treatments:

Treatment 1 (OV): In this treatment the salamander will be confronted with a male olfactory cue (O), in the form of the moist paper towel lining the cage of another male salamander,  and a male visual cue (V) in the form of a video I made of a male salamander.

Treatment 2 (OC):This treatment will subject the salamander to the moist paper towel of another male salamander and a control visual cue (c). The control visual cue is a video depicting the same background present in the other visual cue, only this time there will be no salamander in the clip.

The experimental setup. As you can see, there is a computer screen that playing the video clip. I use two empty cages to contain the salamander within the testing area, but it can still escape if it really wants to. Half the testing area is covered by the salamander's own paper towel and the other half is covered by either a control paper towel or another male's paper towel. I work in the dark under a red-illumination.

Treatment 3 (CV): This treatment is made of a control olfactory cue (C) consisting of a moist paper towel that will have spent 5 days in a salamander cage devoid of a salamander. The visual cue is a video of a salamander this time.

Treatment 4 (CC): This is the complete control treatment. Both the visual and the olfactory cues are controls; this treatment has no salamander smell or image in it.

As the “cue isolation” name suggest, I will attempt to isolate the treatment that solicits the strongest behavioural response in the salamanders. For obvious reasons, I expect the OV treatment to elicit the strongest response. I am also very interested in finding out how the OC and CV treatments compare to a treatment where both sensory modalities (OV) are stimulated.

Each treatment will last 15 minutes unless the salamander escapes the testing area. This is not necessarily a bad thing, mind you, as I am also recording “latency to escape”, meaning how long it takes for the salamander to escape. This information could be valuable because this demonstrates a certain level of distress. One could predict, for instance, that salamanders undergoing the OC, CV and OV treatments will be much more likely to escape then the ones undergoing the CC. As you can imagine, I have to be very vigilant when running this experiment – I don’t want to lose any of my little guys!

How does a salamander behave anyways?

The red-backed salamander is territorial. This means that it does not take kindly to intruders. A face-off between two salamanders will usually determine which one is  dominant and which is submissive. A salamander that looks directly at an intruding salamander or that lifts its trunk off the ground when confronted with an intruder, often arching its back like a cat, is displaying dominant behaviours meant to intimidate. These behaviours can sometimes lead to biting although they never bite to kill.

On the other hand, a salamander that looks away from an intruder or that lays its entire body, including its head, flat against the substrate is being submissive and might very well lose its highly prized territory. Finally, behaviours like running away, climbing the walls or hiding underneath the substrate are all called “escape” behaviours and, once again, these do not bode well as to the salamander’s chances of maintaining its territory.

During each treatment, I will record the behaviours I observe, their length as well as their location. A statistical analysis will help me interpret the data I collect and determine if there is a significant difference in behaviour between each treatment.

Thinking ahead

In the grand scheme of things, this is a rather simple experiment. I can’t imagine what minutiae chemists, bacteriologists or physicists have to demonstrate when planning and performing the experiments that make them great. One must analyze every little aspect and anticipate any problems one might encounter. For instance, previous studies have shown that it takes five days for the salamanders to establish a territory by laying down chemical cues onto the substrate at the bottom of their cages. That means that I can only perform my experiment three nights a week, given that I feed the salamanders on Thursdays and that I clean their cages and replace their paper towels on Fridays.  I have to wait until Tuesday to experiment with proper male olfactory cues because otherwise my cues won’t be valid. I can run certain trials, the ones that use control olfactory cues, on Mondays however. This will allow me to complete experiment 1 and 2 before the end of the semester.

Truly, it is of the utmost importance that I stay on top of things so that everything goes smoothly. Despite having realized that I do not want to pursue zoology as a career anymore, I am as emotionally invested in this experiment as ever. It is my belief that this experiment is worth doing well. With a little bit of luck and some careful planning, I might just make a decent contribution to neurobiology and the science of animal behaviour. Here’s hoping!

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This week has been rather hectic for this 4th year student. I completed my thesis proposal draft in time to send it to my thesis advisor for his comments. I am now in the process of editing it so I can hand it in on the due date, October 7th. I also edited the videos to be used as visual cues in my experiment using Adobe Premier Pro CS3. This means that I am all set for my experiment. I plant to start running it tomorrow night.

Anytime I start something new like this, there is a certain sense of excitement and jittery anticipation. I hope everything will go smoothly. There is really no turning back now, as I must see it through and hope for the best (and hopefully significant) results.

Those were not the only things I had on my mind this weekend. I am currently enrolled in a 4th year animal behaviour course. One of the components of this class is that we must come up with and perform an original animal behaviour experiment to be presented in the form of a poster to the class at the end of the semester. My group, composed of three other girls and yours truly, have come up with the following hypotheses for an experiment on squirrels:

 The “Some Like it Hot” Hypothesis

Campus squirrels are more resistant to common squirrel repellent because they have access to campus garbage and are therefore more accustomed to eating a larger variety of foods than squirrels that live farther from these supplementary food sources.

Prediction: There will be a smaller difference in preference between treated and untreated nuts in campus squirrels, compared with arboretum squirrels.

The “Save Your Cache” Hypothesis

Squirrels from the arboretum that do not have access to garbage year-round will be more likely to cache food then squirrels on campus with access to food at all times.

Predictions: Squirrels provided food in the arboretum more frequently remove it to a secondary location than squirrels on campus whereas campus squirrels more frequently consume the food on the spot than squirrels from the arboretum.

The treated nuts (unsalted peanuts) mentioned above will be soaked in a known squirrel repellent made of onions and cayenne pepper. It has been shown that most rodents, including squirrels, are repelled by capsaicin, the molecule in cayenne pepper that makes it spicy. In order to collect our data, each one of us must spend 4 hours on campus at two separate locations and four hours in the arboretum, once again at two separate locations. In each 1-hour trial, we will lay out ten peanuts that have ether been treated with the repellent or that are untreated. We will observe how many squirrels approach the peanuts, how many eat them and how many removed them.

And so, in an effort to further science, I went out into the cold 9°C afternoon yesterday to observe squirrels in the arboretum. As it turned out, I quite enjoyed the activity. The air was cold but the sun was shining and everyone I encountered on the arboretum grounds had an incredibly cheery disposition. Nature in otherwise urban environments seems to have that effect on people. I could almost pretend that there wasn’t any major construction going on just a short walk away, where my university is building a new gym and arena.

The first two hours of observation were quite uneventful. I saw one squirrel in two whole hours and it didn’t approach the nuts I had laid out on the grass once. Worried, I moved to another location and attempted a third trial.

Success at last

After forty minutes and three squirrels that  had shown absolutely no interest in the treated nuts, a lowly black squirrel walked up to the pile of treats and had himself a feast. Yep, the arboretum squirrel sat there for 6 minutes and ate every one of the supposedly repellent nuts.

Taken at www.toledoperspectives.blogspot.com

Such is the way of science. To be honest, I would be just as happy with disproving our hypotheses. You can’t always get the results you want – but you sure can explain the ones you do get in such a way as to obtain information that is just as relevant!

 

Sunday  Squirrel Watch

This morning, I wanted to go out and observe squirrels for at least two hours but ’twas not in the cards. I woke up in a nick of time, made breakfast and walked to the bus-stop, only to realise that the street was blocked because of a breast cancer charity run (which I applaud by the way). I ran to the main bus terminal but it had been moved for the day. Amazingly, no one could tell me to where.

Considering my options, I figured my best bet was to go north to the location it had been previously moved during the Jazz fest in September. Unfortunately, the city’s transit committee does not think the way I do. They decided that it should be moved in the opposite direction, two blocks South from the main terminal. After all that, miraculously, I managed to catch the bus I had originally set out to catch – What luck!

Three minutes later, I was on the bus, witnessing the first drops of rain in what was to be a rainy day. Genuinely discouraged, I decided to take the bus back home once I arrived at the university because there was no point in laying nuts out in the rain. I would have a quiet morning at my apartment, read the newspaper and eat my now decidedly cold breakfast.

On the bus home, the rain stopped. The skies remained clear for two hours, which would have enabled me to complete the two hours of observations I had planned on doing in the first place. Clearly, Fall is upon us and it is not playing nice.