Lab Packet 1- Ant Behavior

This topic submitted by Laura Broseke, Taryn Nye, Sai Yan Chu, Elizabeth Gerber (taryn_n50@hotmail.com) at 11:19 PM on 10/16/02. Additions were last made on Wednesday, December 10, 2008. Section: Cummins

Natural Systems 1 Fall, 2002 -Western Program-Miami University

Ant Behavior

Which path do they prefer?

Abstract

This research project is being performed to discover the behaviors of ants, specifically their choice of path during the foraging process. A series of bridges will be constructed to observe these behaviors. There will we be four different bridges with two paths each: horizontal verses vertical, long verses short, smooth verses rough, and narrow verses wide. We will be observing the bridges with ants for several weeks, one set will be inside and another outside. These observations will help us to conclude which paths ants prefer. This is relavent to everyday life. It can be compared to human activity in society. We will be able to compare path choices of ants to traveling preferences of humans. So far we haveobserved most of the ants seem to choose the most energy effieceint and time saving path.

Introduction

Although small, and seemingly insignificant, ants are actually quite powerful and intelligent creatures. There are many species of ants, which live in individual colonies. Each colony lives together in one nest. Depending on the location of the colony, the ant species within could have different variables within their neutral characteristics caused by adaptation across populations. (Cahan, 1998) Even within each colony, there are diverse roles each ant must perform in order to maintain the colony; however if there is disturbance in the nest or a new nest introduced, then the ants will either resume their old roles, or take on new roles depending on the length of the disturbance. (Blanchard, 2000) If two separate species of ants encounter the same food source, the ant species that are smaller in body size will be intimidated by the ants with the larger body size. This will result in driving the smaller ants away. (Detrain, 1997)

There are worker ants; their sizes often vary among different species. Ones with largeheads are referred to as soldiers. These workers have no wings, and are physically different from the other types of ants in the colony. Many of the worker ants are regarded as being female; however they differ from the queen due to their degenerated reproductive organs, which leaves the queen as the only egg-laying ant. A female queen is the egg-laying ant, which resembles the workers. The physical difference between the worker and the queen is that the queen has wings on her thorax, and therefore has a well-developed mesonotum, which is dominant in the queen. The third type of ant in a colony is the male. They physically differ from the queen and the worker because they have a compound eye, which is further developed. They also have segmented antenna and mandibles, which have been degenerated. They are similar in some ways to the queen and worker ant because the thorax is developed in both. (Foster, 2001; Anderson, 2001; ThinkQuest Team) As you can see, there are different types of ants, which are responsible for different tasks within the colony.

Thus, the ants do not simply have one simple task of food retrieval. When several ants find a food source, they act in different ways depending on the size of the found food source. If the food source is large, several ants will stay and the rest will return to the nest for ant recruitment. If the food source is small most ants will remain and search for more food around the source. (Mailleux, 2000) At the same time, if a new path is found the ants will explore the path because it has the potential for another food source. (Nonacs, 1998) When a food source is found, the ants will continue to retrieve food for the nest until the food source is depleted. (Robson, 1997) Here, you can see that they are intelligent and thoughtful in the manner they distribute work in order to maintain a successful colony. In our study we are observing the behavior when they are presented with different choices of paths. When finding a path from the food source to the nest ants are capable of finding the shortest, most convenient path. Lines are often formed in species of ants traveling to a food source through the use of a pheromone trail, which helps to keep the line. This trail also explains how ants are able to contact each other if the line is broken. If any obstacle appears in an ants' trail, the leading ant chooses a new direction to travel, and it is expected that half the ants may travel in one direction and half in the other direction. The ants, which choose the shorter path around the obstacle, will recreate the pheromone path more quickly than the ants that choose the longer route. (ThinkQuest Team.) This explains why the ants take the more convenient path.

Predictions

We are performing an experiment to discover the traveling behavior of ants when attempting to acquire food. We will try to answer the question; which path is more convenient to the ants. We will perform this by constructing a series of bridges, with the food placed on a platform elevated by different paths. Each path will have a different variable, and we will use these variables to observe the most favored path(s) of the ants. These paths will include four contrasting characteristics. The first set will have a direct path compared to a deviating path. The second will have a smooth surface compared to a rough surface. The third pair will have a vertical versus a horizontal path, and the final pair will have a narrow path versus a wider path. As we observe the ants, we will record how many ants are on each path by assigning each person in our group one pair of paths with opposing characteristics. We expect that the ants will favor the most convenient path regarding time and energy. In the first pair of paths, we believe the ants will choose the shorter route compared to the longer route based upon the time factor, and the conservation of energy. We also expect that in the second pair of paths, the ants will choose the smooth surface over the rough surface. With the third set of paths, we expect the ants to choose the horizontal path versus the vertical path. In the fourth pair, we expect that the ants will choose the wider path instead of the narrow path. We decided to perform this experiment because we are interested in discovering the paths that ants will choose to travel. The observations will be entertaining because our curiosity will coax us to further study the ants to explore the behavior and patterns the ants perform. We will look forward to discovering how ants, known as simple creatures, portray themselves differently as we observe the complexity within the colony.

Relevance of the Research Question

The inspiration for this experiment began with an article that our group found particularly interesting. We chose to modify the experiment that we researched by adding more variables to their design. The experiment, which we researched, used the idea of horizontal versus vertical paths to discover the preference of ants when leaving and returning from a food source to their colony. They discovered that ants chose the vertical path when the horizontal and vertical were the same length. As the vertical path reached a certain height, the ants chose the horizontal path instead. We modeled our experiment from the one above and added different types of paths to discover further ant preferences. Along with the vertical and horizontal path we added length (short versus long), texture (rough versus smooth) and, path width (fishing line versus four cm. plank). Our experiment could relate to the real world because we are learning about ant society and how they prefer to travel to wards food. These test results will allow us to discover any energy or time efficiencies that ants may instinctively use. These efficiencies that we may discover could be related to human characteristics in the human workplace and society. When comparing human preferences to ant preferences we may find similarities and differences in paths that will be present. We could also relate this experiment to the real world, because we can learn from the efficiencies in ant colonies, and apply these to our own lives and the advancing technology. (Spice, 2001) Generally humans would choose the horizontal, wide, smooth, and short path because these are the easiest to travel and therefore the most efficient. After our research we will be able to compare a smaller scaled organism to the scheme of life in which we live.

Materials and Methods

Our experimental design consists of two factors, one study in nature environment and one study in a controlled environment. We will begin with testing variations in bridge designs, as well as testing food to use (See Initial Bridge Design). We are constructing two sets of four bridges to use in both environments, in other words the experiment will be done in the same manor both indoor and outdoor. Each set consists of a series of four bridges each with two opposing paths. The food substance placed on a small platform at the top of each path will either contain 'ant food' or a sugar substance. The reason the food type may vary is because the ants outside seem to be more attracted to sugar, with the ant farm came with specific ant food.

We will observe and record each bridge over several weeks until we reach at least 20 observations. At the end of the outdoor and indoor observation we will fill out the information needed to complete the Data Sheet. To maintain a strict schedule, we will be following the Time Line.

The materials we will be using include: foam core, plastic sheeting, chipboard, wire, tape, glue, and cardboard. The use of these materials is shown in the Bridge Specification Sheet. The other materials we will be using include a purchased ant farm; six inches in length by four inches in height. The farm comes with a tip proof stand, tunneling sand, and an ant watchers guide. These materials will be used as the indoor habitat, which will be placed inside a fish tank. This farm also includes an 18-inch flexible ant way connecting tube, which we will cut into two parts, so that as the ants exit the farm there is an equal distance to the start of each bridge at either end of the fish tank. Over the tank we will place plexy-glass so that the ants will not escape, yet we will be able to access them easily to feed and water them. Our indoor study will be open for observation in the science lab. Students will be able to post their time, conditions, and date of observation, as well as any comments they may have on our study. They will be able to record all this information on the Student Chart.

Student Involvement

As the week of our presentation approaches we will have all of the other groups take several observations of the ants inside and outside. These students will be instructed on where the ants are located, what to look for, and how to record data. Then when we present we will use the data to construct different charts to compare and contrast the collected information. We will also share the data that we have collected. We will explain to them some of the problems that have arisen in our experiment, and background information on ants.

Pictures

1. Ant Hole With Jelly

2. Ant Hole

3. Jelly

4. Bridge Design One

5. Bridge Design Two
References

Anderson, Carl. 2001. The complexities and hierarchical structure of tasks in insect societies. Animal Behaviour, 62: 643-651.
In this journal article, it is discussed that tasks within a colony of insects (including ants) are divided by the complexity of each task, and those within the colony work together to complete the whole task. This can be beneficial to our experiment, because the task needing to be performed will give us better results if all the ants within the colony are completing a task, and becoming part of our experiment.

Blanchard, G. B. 2000. Division of labour and seasonality in the ant
Leptothorax albipennis: worker corpulence and its influence on behaviour.

Animal Behaviour, 59: 723-738.
This article relates the ecological success of social insects to the division of labor. It states that these roles can change when there is a disruption in their nest. For example, in short term disruption "such as a colony emigration, all individuals revert to their previous roles. In removal experiments there is a delay of days before individuals move into vacated roles. This could relate
to our ants as they are being shipped from California to Ohio and put into a different environment.

Burd, Martin. 2000. Foraging behaviour of Atta cephalotes (leaf-cutting ants): an examination of two predictions for load selection. Animal Behaviour, 60: 781-788.
This article talks about two different ideas about how mechanisms explain foraging in leaf-cutting ant colonies. The author used five colonies to observe shifts within the colony. Most used shifts for workers at the beginning and the end of the line. The recruitment requirements were also observed within the colony.

Cahan, Sara. 1998. An abrupt transition in colony founding behaviour in the ant Messor pergandei. Animal Behaviour, 55: 1583-1594.
This article suggests that although species are evolutionary units they can vary across populations. There are some neutral characters among them, but a variable may be in their behaviors depending upon their geographical locations. This is relevant to our project because the two ant species may choose different paths.

Denny, Adrian. 2001. Foraging efficiency in the wood ant, Formica rufa: is time of the essence in trail following? Animal Behaviour, 61: 139-146.
This is the journal that we are basing our experiment on. It discusses how ants chose the shortest and easiest path to food, from the colony. This was tested with a series of bridges that were made up of short, long, horizontal, and vertical paths. The bridges were used in observation of the choices that ants made.

Detrain, Claire. 1997. Scavenging by Pheidole pallidula: a key for understanding decision-making systems in ants. Animal Behaviour, 53: 537-547.
This article discusses how different sized insects make trails from food to the nest, and how these patterns differ from each other. The smaller the insect, the more they will stay away from the food. When there are other larger insects near the food, the smaller ants will not go near the food.

Foster, 2001. William, and Shingleton Alexander. Behaviour, Morphology and
the division of labour in two soldier-producing aphids. Animal Behavior, 62:
671-679.
This article states that ants are a social species. Each has roles in it's community. These roles are important to the "ecological success of the social insects. Worker ants have specific jobs to do; these ants become specialized and efficient at their work.

Heinze, J. 1999. Worker age, size and social status in queenless colonies of the ant Leptothorax gredleri. Animal Behaviour, 58: 751-759.
This article will be helpful in our studies because it describes how social status does not depend on the age of the ant. This will be an asset in our observations, because with this knowledge, we do not have to worry about social discrimination among the ants, which might further affect our results.

Louis Jacobson, 2002. Antcolony.org.
http://www.antcolony.org/
This site describes how ants use their offspring as slaves in some instances.

Mailleux, Anne-Catherine. 2000. How do ants assess food volume? Animal Behaviour, 59: 1061-1069.
This article was helpful in planning our experiment, because it tests how ants recruit for food, and this will play a large part in out study. When ants find a large amount of food, they will return to the nest to form a recruitment trail. If there is only a small amount of food, several ants will remain to find more food. This will be interesting to examine along with the paths the ants choose to follow. If the food source provided is plentiful, we expect to see a few ants at one point, and later return with a larger amount of ants.

Nakamura, Kurumatani, 1998. Charles Sturt University.
http://www.csu.edu.au/ci/vol06/nakamura/nakamura.html
Worker ants have several tasks; searching tasks, carrying tasks, and recruiting tasks. In our experiment we may be able to observe the same type of system.

Nonacs, Peter. 1998. Patch sampling behaviour and future expectations in Argentine ants, Linepithema humile. Animal Behaviour, 55:519-527.
This article will be important in our study, because it has many of the same questions as we will have. The article focuses on the paths ants choose, as they are newly presented. The goal of traveling the path is to acquire food, similar to our experiment. Even if a new path is presented to the ants, it is possible that they would choose that path, even if there is never food on the new path. This type of "learning" observation is closely related to the experiment we will be performing.

Robson, Simon. 1997. Division of labour and 'foraging for work': simulating reality versus the reality simulations. Animal Behaviour, 53:214-218.
This article was useful to our experiment because it discusses the work division according to age of a worker ant. This could have a great correspondence to our experiment, because if the work is considered gathering food, we should expect to see ants of certain ages carrying out specific tasks. It also argues that ants will find work and continue to perform until the work is done. In this case, we should expect to see ants working to take the food back to their nest until the entire food sample has disappeared.

Science Education Department, University of Arizona 1997.
http://biology.arizona.edu/sciconn/lessons/shindelman/ant_info.html
This site is a general example of many characteristics of ants and the roles they play, their history, and body make-up.

Spice, 2001. PG Publishing.
http://www.post-gazette.com/healthscience/20010730antshealth2p2.asp
This site is another example of ants living in a controlled environment. The scientist studies their behavior of food foraging and their social roles.

Tarniello, James. 1997. Ecology, evolution and division of labour in social insects. Animal Behaviour, 53: 209-213.
This article argues that division of labor may not be based on age. The division is thought to differ for all species, and evolve individually. If this is the case, we will soon learn how our ant colony's labor is divided.

ThinkQuest Team.
http://library.thinkquest.org/c004404/colony.htm?tqskip1=1&tqtime=0924
This website was helpful because it gave ample information about ant types within a colony, and the roles that they perform.

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