This week I've learned how to do quite a few things regarding ant behavior. This first thing being how to run a pathfinder assay. A pathfinder assay's purpose is to find pathfinder ants. Just a reminder, pathfidner ants are ants which have to ability to sense pheromone trails longer than normal ants. Unfortunately, this is a long grueling process that takes a whole day to complete. First, a trail needs to be set up. This is done by placing a bridge between an ant colony, and a long corridor which leads to a food source. Then, it is left for an hour and a half which is enough time for the ants to develop a trail between the nest, and the food source. then, after that hour and a half, the bridge is removed, and the pheromone trail is left to sit for 3 hours, which, in theory, only pathfinders would be able to follow the path then. And after that long wait, 10 individual ants are tested to see if they follow the path. Unfortunately, only 10 can be tested because the ants being tested can lay fresh pheromone on the trail which can render the test useless. At the end of the day, usually only 1-2 pathfinder ants are found after each pathfinder assay.
As you can guess, only one or two a day is a very small amount. We would like to increase our quantity of pathfinder ants. NJIT has developed a program which is supposed to test whether an ant is a pathfinder by looking at their movement. Pathfinder ants only move in concentric circles, which nonpathfinder ants move from point to point. Justin Walsh and I have created a set up where the ants can be tested for this. First, we got a large, white box which a camera opening at the top. We set up bright lights evenly throughout the container to avoid letting that be a variable in the testing. The camera is set up so the ant is the only dark object in the container, so the program will be able to follow the path of the ant fairly easily. After we set this up, we send a test run of an ant moving around inside the box, and right now we are waiting for a response from them.
A side project that I have been working on is nest preference tests. The purpose of this test is to determine nests of what heights and nest opening width ants prefer. We have nests with three different heights and three different width of nest openings. the set up for this test is a large container, and in it are 2 nests of different combinations located at each corner of the container, and a nest which has the ants in it. Once you "break" the nest with the ants in it, they search for a new nest, and we are testing to see which nest height and size they would prefer. After doing only about seven different tests, I can already see trends in which height and nest opening they prefer.
I have also learned and done a few extra things in the lab. One of then is taking thirds (large, yellowish ant eggs) from an ant colony and transporting them to genetic specific colonies. This is done because thirds are special in that they break down wastes in ant colonies. If an ant colony doesn't have thirds, they would be unable to survive very long. So to take thirds out of a colony, you must do it under a microscope. To pick up the eggs, you have to use a small paintbrush because it does not damage any of the eggs. And this is a very tedious and difficult job. There are usually other eggs, which we don't want stuck on the thirds, and it is very difficult to avoid breaking the eggs and removing other eggs from being attached. In the end, I have collected 350 thirds so far from colonies.
The last, obligatory task I have learned is ant feeding. So twice a week, the ants need to be feed. This is no easy task. There are about 200 ant colonies in this lab, and each individual one needs to be fed fairly frequently. Ants eat a diet of a green sugar mixture, small worms, and water. For each colony, you have to take out the old broken down food, the expended water tubes, and replace them with new food. This can becoming painstaking, but I'm sure since I'm the youngest, I'm probably gonna be doing most of the feeding, so I'll have to get used to it.
A few side notes/ interesting things, there is an unknown species of ant which we have colonies of, which are conveniently labeled "Not Monomorium pharoanis". And boy, these ants are fiesty. When feeding them, they move very quickly, and they bite.
The apartment side of things has been fairly interesting also. The first night I got there, there was no sign of Dan Fine, but instead, I was pleasantly surprised to find that I have two others living with me in the apartment, along with Dan! Although it was not what I was planning, they are each very nice guys, and one of them even played frisbee and watched Disney channel with me one night. this was the first time I was living away from home, and they were more than helpful in showing me how to do my own laundry, and cook food.
So far, I have loved the EXP experience at UPenn! I cannot be happier with the people I have around me, and the work I have been doing, and I am hoping the upcoming weeks will be as wonderful! And now, a few pictures:
Above is a picture of the Pathfinder Assay.
Above is the box in which the program will detect the ant's movements.
This is a picture of a Nest Preference Test. These tests are done inside the box pictured above.
This is one of the rooms where the ant colonies are kept. This was taken midway through a feeding session. There is another room holding ants identical to this one; the rooms are kept very warm and humid for the ants, which makes feeding even more difficult.
No comments:
Post a Comment