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First post- biology experiment proposal

  1. Sep 7, 2004 #1
    ok i'm new to the forum, there is a mass amount of intelligence here i have seen over the past few days reading. this is my first college biology class, and i am probably going to major in zoology because of a strong passion for understanding anima... ha oh yes back to the point.. we have to turn in a proposal of some sort of what we want to do for an experiment so this is what i came up with so far. for all the brains here i am sure you will find many faults, but i want to hear any comments please. this is still an entirely incomplete idea but i think its a strong base to work from. i actually got the idea of hanging the food off the floor from someone who posted in a thread i am sorry i cannot remember the name of you. any ideas to modify or add, subtract from what i have already LET ME KNOW! i want to get awesome grades and you fellows can help me out. thanks!

    Canine Memory

    To see how my dog holds memory of the day before (or how he is remembering of food not always being where it was). See if time levels drop over time as the experiment is repeated, also note time between two foods getting shorter

    Get string and hang chicken in room 4 feet from the ground when subject is not around. Bring him in, and instinctively I believe he will head for the floor, seeing as the scent is fresh it won’t be very distinct as to where it is. I will track the time it takes for him to find the treat. Then I will repeat the test no more than 5 minutes later with another food object put in the same spot to see if he relates treat to place no matter what the smell, or if a new smell will make him look over the floor again. Track time. Go to new room and do the same test over again. Is he learning that it isn’t going to be on the floor all the time or will he still sniff along while it is suspended over his head the whole time? Track times.
    Repeat the tests for 5 days. Do the times get any shorter? Is there a relation in the associating of two foods being in the same place?

    Modified Chi formula for determining correlation

    x= first food time-second food time Ex: 10
    ------------------------------ = ------ = .25
    first food time 40

    A way to tell is using a modified chi2 test to see if the times get shorter between the two foods in relation to the times of earlier days. The reason being is if say the first day it takes 40 seconds (first treat) and 30 seconds(Second food) that is a 10 second difference, or 1/4 the time cut off. If by the third day he gets it in 10 seconds and 6 seconds that is only a 4 second difference, but that is 2/5 the time cut off. 1/4, or 25% decrease in time between findings is a substantial difference from the 40% decrease in time by the last day of testing, seeing as anything over 5% difference should be considered substantial. This means there is a correlation between him noting that there is a smell no matter what it is, and that this is where the food could be so lets look up too. Or is he is just adapting to food being there? The question still lies: for him is it memory or instinct that makes the times shorter between two foods(supposing there will be shorter times)???
  2. jcsd
  3. Sep 7, 2004 #2


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    You've got a good start to your project. I suspect, however, that your dog's nose is better than you think at guiding him to food, so that he'll head straight for the treat once put into the room. If that happens, you don't have a way to test for a time difference due to learning.

    I'd suggest a different way of presenting the treat to see if learning is involved or just a good nose.

    Find a place in the house the dog doesn't often get treats (for example, you don't want to use the usual location of his food dish, but perhaps a place in a bedroom). Now, get a container you can put the treat in, but will be easily cleaned to get the smell of the treat off it later (a bowl or cup will be fine)

    You will need three parts to the experiment.

    First, do a pre-test where you time how long the dog takes to find the empty container without ever seeing food in it (in this case, you are measuring how long it takes for the dog to approach a novel object in the room).

    Next, you need a training part of the experiment. During this time, you don't need to time the dog, but you can if you want, in case you find the information helpful later. In this part, put a treat in the container, and leave the container open, or open the container while the dog is there. This is to teach the dog where to find the container, and to associate the container with a treat (have you learned about Pavlov's conditioning experiments in any of your classes? If not, that would be a good one to look up in a book on psychology as background for your experiment).

    In your last part of the experiment, you do the post-test. In the post-test, you again put the empty container in the same spot and time how long it takes the dog to go to the container.

    I've basically just used your initial idea and spiffed it up a bit. Now, to make sure I'm not doing all your homework for you, here are some questions for you:

    With this experimental design, do you see which group is the control and which is the experimental? Do you understand why you would put the treat in the container during the training part but not the pre-test and post-test parts? What outcome would you predict? Your first experimental design idea included a way to replicate (repeat) the experiment, which is an excellent component of any experimental design. How would you replicate the experiment with the design I've suggested? What could you do differently to make sure the dog was learning to associate the container with the treat instead of the place where you put the container?
  4. Sep 7, 2004 #3
    I think I see what you are getting at. Instead of using food as a control I am using the bowl (or attention to it?) as a control and the treat as the experimental. I like the idea of this a lot more simply because I was wondering the same today...what if he gets it right away? Putting the treat in the bowl only gets him thinking instead of just “hey this is something new in the room” now it turns into “hey there is good stuff here ill come to it whenever I see it” which will really get me the results im looking for- the actual amount of learning that is involved. What I am wondering now is how to repeat the experiment so I can see if he learns more over time. It seems to me once he learns to associate the bowl with treat, there is no getting his mind set off of that. The only thing I could think of is either moving the bowl or using a different bowl, but doesn’t the control have to stay the same? If I take it out of the surroundings its in that messes up any results I’d get :/ eh I think I am going to look for some of the Pavlov’s reading you suggested. AH wait I think maybe I have it. A different dish in a different room would be a whole new setting but still with his memory getting stronger each time he is taught “new bowl= food no matter where it is.” so I could compare the times just as I was before but this time for the 5 days I will do a different setting and new control each time.. Then relate the first days results
    ( [pre test time- post test time]/pretest time ) to the 5th days result and see if the time is getting noticeably smaller. Something tells me that it is going to be much closer times than my first experiment. But now the only question...is my professor going to approve of this because it seems to not be so much biology and more animal psychology haha.. Hey it does have an experiment though and it even includes a formula we learned in class ( chi squared) I just changed it up a bit..or a lot. I think she will say ok because she is cool like that. Hopefully.
    So how am I looking now guys? Btw moonbear thank you entirely for your efforts
  5. Sep 7, 2004 #4


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    Close, but not quite. The pre-test is your control, before the dog has had a chance to learn anything. The post-test (no treat in the bowl) is your experimental, to see if the dog has learned the bowl is supposed to have a treat, even if it doesn't in that trial.


    You're close. Think about how you were planning to repeat the experiment in your first design. This one isn't much different. New bowl, new room, AND new treat.

    For each new location, bowl and treat, you need both a pre-test and post-test. Another way you could replicate your experiment would be to do the same test with a friend's dog, if you know someone else who would let you try this with their dog.

    That's possible. You might want to compare pre-test times from your different replications to see if the dog generalizes what he has learned from location to location, or if he has to learn the location of the treat bowl in every new room.

    Well, learning requires biology. If you do a little background research on how the brain is involved in learning, this would be a perfectly good biology experiment...at least in my opinion.

    Chi-squared isn't really the right way to analyze the data, but the math you proposed actually will work (what you suggested doing isn't actually a chi-square test). Chi-squared compares proportions, not differences in time. What you've suggested doing, though, of calculating the time difference pre-test and post-test and then dividing by the pre-test result sounds like a very good way of getting your results. However, you could simply calculate the difference without dividing by the pre-test value. I don't know if you are being taught any other types of statistics. There are statistical tests you can use to directly compare pre-test times to post-test times as long as you repeat the experiment a few times, but that might be too much for what you need to do for this assignment. You might instead want to say that you expect the post-test to be shorter than the pre-test, so expect a difference of post-test minus pre-test to be less than zero (a negative number), so you will accept your hypothesis if the average of all your replicates is less than zero, and reject your hypothesis if the average is greater than or equal to zero.

    It sounds like you're very much on the right track with this. Good luck! Hopefully your teacher approves the experiment because it really sounds like a fun one to do :wink: It sure seems better than the usual biology experiments students do, comparing things like how fast seeds grow with or without water or something pretty boring to watch like that. I'm sure your dog will be very happy to be the subject as long as he gets lots of treats!
  6. Sep 8, 2004 #5
    ha i just typed a huge respose but i wasnt logged in when i tried to post so it deleted it..gotta go to class though i will post again tonight
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