Title: You talkin to me?: Investigations in animal behavior Author: Kasey Yturralde Date: Fall 2004

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1 Title: You talkin to me?: Investigations in animal behavior Author: Kasey Yturralde Date: Fall 2004 Background Lab uses ethology to introduce students to the scientific method and stresses inquiry based learning. Ethology is the study of animal behavior and usually emphasizes behavior in the animal s natural habitat. In this lab students will use an ethogram to quantify animal behavior. Animal Behavior Animal behavior is a popular topic for many PBS and Discovery channel nature shows. In particular, fantastic and bizarre behaviors are often featured because they are inherently interesting to watch and because they are curious from an evolutionary perspective (i.e. How did these strange behaviors evolve? What survival or reproductive advantage do they give that particular animal?). However, animal behavior has been important for humans since prehistoric times. The study of animal behavior, or ethology, can even be found in cave paintings, which depict social wolves and solitary bears (Sinervo 1 ). Humans that foraged for various animals would have needed a working knowledge of the habits and whereabouts of their prey. Therefore, early animal behavior studies were very much an applied endeavor. These early applied animal behavior studies contrast with the birth of modern ethology in the 1930s with studies conducted by Niko Tinbergen, Konrad Lorenz and Karl von Frisch 2. These three scientists received the Nobel Prize for medicine in 1973 for their research in ethology. One important aspect of ethology to emerge from this period is Tinbergen s analytical approach to behavior comprised in Tinbergen s four questions. Tinbergen addressed four main areas of ethology: causation, development, evolution and function or survival value (for more, see animal behavior lecture series from UCSD 3 ). Animal Communication The study of animal behavior covers a variety of topics, which include predation, foraging, habitat selection, communication, sociality and mating. One lab would scarcely be able to provide a survey of all these topics, let alone provide any detail. Therefore, this lab will focus on animal communication. By focusing on one aspect of animal behavior, it will be easier to anticipate student questions and to conduct a guided inquiry lab exercise. If a more open-ended lab is desired, then this lab could be left open so that students could explore any aspect of animal behavior. Why study animal communication? Aside from the fact that it is inherently fascinating, there are some compelling arguments for the study of animal communication. The ability to communicate can be as important to an individual as finding the appropriate habitat. If a particular species is at risk of becoming endangered then having a thorough Alcock, J Animal Behavior, 7 th Ed. Sinauer Associates, Massachusetts

2 understanding of the requirements for mating, foraging and predator defense becomes incredibly important. For instance, knowing that individuals are unable to attract mates because of nearby light or noise pollution enables biologists to effectively manage and ultimately conserve species further endangerment. Because behavioural traits can be shaped by natural selection and may change over time, it is possible to understand evolutionary relationships among animals using animal signals 4. Incorporation of behavioural traits along with morphological traits may elucidate a more accurate taxonomic classification of species. Knowledge of animal communication also has very practical applications. There are many insect pests, which rely on chemical communication for mating. Knowing how insects use these signals allows us to interrupt their communication and subsequently their mating. This approach to handling potentially devastating pests enables us to manage them with biological controls and integrated pest management. Lastly, the knowledge of animal communication can be used by zoo managers to design zoo habitats that encourage natural behaviour and minimize stress on captive animals. Natural selection Charles Darwin proposed the theory of natural selection as a mechanism that explains how plants and animals evolve. In this lab, it is intended that natural selection describes a process, a mechanism of evolution and adaptation describes a trait that is particularly well-suited to an environment. Natural selection is the differential survival and/or reproduction of individuals due to differences in traits. There are three necessary criteria in order for natural selection to act on a particular trait 5 : 1) variation in a trait; 2) trait must be heritable; 3) trait has effect on whether individual survives and/or reproduces. Let s use an example to better illustrate these criteria. Take ladybugs living in Arizona and the pattern of spots as particular trait. Being very hot, ladybugs might experience (natural) selection on the pattern of spots if having more black spots was a disadvantage due to overheating. 1. Variation in a trait. a. The first point, variation, is important because there must be alternate forms of a particular trait in order for one to be favored over another. If all ladybugs have the exact pattern of spots, then there would be no change in this trait, natural selection cannot favor one over another if all ladybugs look alike. 2. Trait must be heritable. a. If it is favorable to have few black spots, then those particular beetles may live longer and end up with more offspring. However, this trait must be passed on to offspring (i.e. heritable) in order for this trait to increase in frequency. 4 Bradbury J.W. and S. L. Vehrencamp Principles of Animal Communication. Sinauer Associates, Sunderland, Massachusetts, pg 6. 5 Alcock, J Animal Behavior, 7 th Ed. Sinauer Associates, Massachusetts. 2

3 3. Trait has effect on whether individual survives and/or reproduces. a. In order for selection to act on a trait, the chances of an individual surviving or reproducing must be affected by the trait. In our example, ladybugs with black spots will only decrease in number over time if these spots reduce the possibility of survival and/or reproduction. Typically natural selection has been discussed in terms of morphological traits such as the shape of limbs. However, any trait that has a genetic basis can be acted upon by natural selection. Therefore, traits such as visual signals, social behavior and male courtship displays are also subject to natural selection. Adaptation In this lesson adaptation will be treated as the result of natural selection, as opposed to the process itself. An adaptation is any trait that has resulted from natural selection. Adaptations are traits that increase an individual s chance of survival and/or reproduction compared to other alternate forms of the trait. This means that an adaptation is not necessarily the most perfect possible trait. An adaptation is just a particular form of a trait that works best compared to other alternate forms. Natural selection and communication How can we learn about natural selection in animal communication? Why is there such great diversity in the types of communication employed by different animals? It might be that animals have particular adaptations for communication according to the types of environments they live in. In order to learn more about natural selection in terms of animal communication, let s consider the interaction between animals and their environment. Rufus A. Johnstone 6 provides an example of how environment is important for selection on animal signals in warblers. Warblers of the genus Phylloscopus live in the forests of Kashmir, India. They are small, green birds with varying patterns of pale patches on their head, wings, rump and tail. These color patches are important for finding and keeping territories within the forest. Researchers found that species with many pale color patches were more conspicuous and lived in very dark forest habitats. On the other hand, those birds with few color patches were relatively inconspicuous and lived in much brighter, open habitats. Johnstone suggested that species have evolved visual signals that best communicate within their particular environments. Those species that live in dark habitats have adaptations, bright and conspicuous signals, allowing them to best communicate to other warblers. Species inhabiting sunny habitats are able to communicate without such bright visual signals. These types of adaptations for communication can be found in all lifestyles such as terrestrial, fossorial, arboreal and aquatic. The Trials of Life video shows examples of all modes of communication including visual, chemical, auditory and vibrational. 6 Johnstone, R. A The evolution of animal signals. In Krebs, J.R. and N. B. Davies ed. Behavioural Ecology: An Evolutionary Approach, pp Blackwell Scientific Publications, Oxford. 3

4 The above description of animal behavior is mostly in terms of the ultimate questions. That is, the majority of the discussion addresses why animals act the way they do, how particular behaviors or communication is advantageous to individuals. However, there are also a plethora of proximate questions that address how animals respond to their environment and each other. Here I will provide a brief description of this type of approach to animal behavior. Behavior can be broken down into three steps 7 : Stimulus Animal receives some type of stimuli that can be external (from the environment or other animals) or internal such as hunger. External stimuli are detected using any variety or combination of the senses: touch (includes vibrations), chemoreception, auditory, or visual. Neural integration Neurons receive and process neural information. Response Depending on the stimuli, animals then set off a pattern of nerve impulses from the central nervous system that are coordinated into sequences of muscle contractions (ex muscles in legs coordinate movement and escape response to predation) Objectives: Student will be able to 1. Collect detailed observations of animal behavior 2. Develop a catalog (ethogram) of animal behavior 3. Measure various animal behaviors (collect quantitative data) 4. Identify the various modes animal communication 5. Become familiar with the scientific method 6. Develop simple investigation of animal behavior (within small student groups) 7. Collect, analyze, interpret and report data in written format. Goals: Students will learn 1. The importance of maintaining objectivity while making observations and identifying animal behaviors. 2. How animal behaviors are traits that can be acted on by natural selection 3. The importance and advantages of quantitative data. 4. The importance of repetition and controlled variables in experimental design. 5. How to distinguish between the various components of the scientific method. 6. The importance of using mathematics in discerning patterns in nature. 7. The importance of presenting experimental results and conclusions. 7 See website and Alcock, J Animal Behavior, 7 th Ed. Sinauer Associates, Massachusetts. 4

5 AZ standards Grades 6-8 Strand 1: Inquiry process Concept 1: Observation, Questions and Hypothesis Formulate predictions, questions or hypotheses based on observations. Locate appropriate sources. Concept 2: Scientific testing (investigating and modeling) Design and conduct controlled investigations. Concept 3: Analysis and Conclusions Analyze and interpret data to explain correlations and results; formulate new questions. Concept 4: Communication Communicate results of investigation. Strand 2: History and nature of science Concept 1: History of science as a human endeavor Identify individual, cultural, and technological contributions to scientific knowledge. Concept 2: Nature of scientific knowledge Understand how science is a process for generating knowledge. Grade 6 Strand 4: Life Science Concept 3: Populations of organisms in an ecosystem Relationships among various organisms and their environment. Grade 7 Strand 4: Life Science Concept 3: Populations of organisms in an ecosystem Relationships among various organisms and their environment. Grade 8 Strand 4: Life science Concept 4: Diversity, adaptation, and behavior National Standards Content Standard A: Science as inquiry Abilities necessary to do scientific inquiry Understanding about scientific inquiry Content Standard C: Life Science Regulation and behavior Diversity and adaptations of organisms Content Standard G: History and Nature of Science Nature of science 5

6 Materials Field crickets: These can be obtained from local pet stores. You will probably be sold crickets of various ages. It is important to remember that any territorial behavior or courtship and mating behavior will be limited to adults and requires both sexes. You may have to do some sorting if there are any behaviors in particular that you want students to observe. Cat food Lettuce, grapes, other juicy fruits or vegetables Clear, plastic terrarium (one per table) Ruler Graph paper Access to wall clocks Time The minimum time required for this lab is 5 days following the schedule outlined below. Pre-lab activity Trials of Life video and You talkin to me? activity Day 1 Observations and ethogram Day 2 Develop questions, hypotheses and experiment using worksheets Day 3-4 Conduct experiments Day 5-6 Analyze data, write up into poster Day 7 Poster presentation Grade level This lesson plan is designed for middle school grades 6-8. However, it could certainly be adapted for high school grades. Procedure Pre-lab activity Video on animal behaviour: The Trials Of Life: Talking to Strangers Animal communication game: You talkin to me? o Play this game after the video so students have an idea of the variety and extent of animal communication o Attach animal bio to back of shirt. Advise students NOT to look at their identities. Students will attempt to find out who they are and how they communicate by asking other people ONLY yes/no questions. o Hand out worksheet to accompany video. o Goals for activity and video: Encourage interest in animal behavior Introduce students to the concept of adaptation and natural selection Encourage excitement about upcoming lab exercise with crickets o Content Introduce students to diversity of animal communication Modes of communication o Chemical o Auditory o Visual 6

7 o Tactile o Multiple modes of communication Animal behavior Two main types of questions can be asked about behavior o How questions are answered by describing how an animal is biologically equipped to behave, what the mechanisms are that allow for behavior o Why questions ask for explanation about why a behavior is beneficial to an animal Behavior is coordinated response to environmental stimuli. These responses may be learned over time Behavior are determined in part by an animal s genes o This means that behaviors are traits that can evolve Communication involves two individuals Sender Receiver The cooperative transfer of information from the sender to a receiver SEE Worksheet #1 Lab exercise Throughout lab, students will record their observations, procedures, background information and data in a journal. Day 1 In this lab students will have one day of observation time with their animals, field crickets. Initially, will have students fill out Worksheet #2 that guides student observation in a way that will reveal differences in behaviour and morphology of nymph, adult, male and female crickets. Subsequently, time will be spent making general lists of behaviors and in a discussion of what constitutes behavior. By the end of the day students should have constructed ethograms. See Worksheet #3. The concept of an ethogram will be discussed, but the students will be able to develop their own format. This will include a class discussion of: what constitutes a behaviour danger in assigning emotions to animals how do scientists measure and quantify behavior Below is an sample ethogram: 7

8 Possible behaviors: antennae cleaning, leg cleaning, eating, singing, chasing, fighting, biting, drinking water, mating and laying eggs Time Behavior Comments There are two possible techniques for observing animals. They differ according to the number of individuals sampled in a given time period. See summary below from: ( Focal approach. With this method, you locate a single individual and follow its behavior for a standard time (or as long as possible up to that time). If a focal individual moves out of your view, then you start a new sequence of observations on a new focal individual. Selecting the focal animal can be systematic (you might just follow young animals) or randomized (select a random number from a table, then follow the nth individual encountered). During a focal study, you should record the following data as they occur: the context (date, time, location, weather, habitat, social context) the focal animal ID (if you can identify them uniquely, or just by #1, #2, etc) the sequence of behaviors the duration of behaviors (using a stopwatch or Ethoscribe software) the immediate consequences (e.g. responses of other individuals, etc.) How you record your data will vary with the stage of your study. When building your catalog, you will have taken extensive notes. That won t work when trying to quantify how an animal spends its time. Organized data sheets are critical for focal studies, because they allow you to record data quickly and efficiently during the observation period, and to tabulate the results accurately afterward. A well-written catalog of behaviors will allow students to create a form for collecting data for the quantification phase of the ethogram. An example data sheet is available online. We will discuss how to use this sheet in class. Please feel free to modify this (for example, you may prefer to give the first time of observation, then use a stopwatch to record the duration of each behavior). Survey approach. This method involves watching many individuals at the same time. At systematic (or randomized) times, you count the number of individuals performing each possible behavior. For example, if you are watching a flock of ten geese in a lake, you might set your timer to alert you at one minute intervals. When the timer goes off, you note what each of the geese in the flock are doing at that instant, as well as the context and consequences of their actions. You will repeat this every minute for your entire observation period. Creating a data form that can be filled in quickly also facilitates taking survey data in the field. Ethoscribe software also allows you to use the survey method. Day 2 The second day students will work develop their own questions pertaining to the behavioral patterns observed. First, we will discuss, as a class, the types of observations that everyone made and what types of questions they have. Students 8

9 will work on generating multiple hypotheses to explain these questions and discuss the importance of testable hypotheses and alternative hypotheses. Students will generate predictions from their hypotheses and simultaneously develop experiments. On this day emphasize the idea of a fair test; this will introduce students to using controls and conducting tests that only test one variable at a time. During discussion, give a (prepared) example of an experiment that has a number of characteristics that should be changed or improved. This example will not use crickets because otherwise students will end up just using the example for their experiments. See Worksheet #4. Day 3-4 The second week students will carry out their experiments in groups of two or three and test their hypotheses. Students will collect quantitative data in their journals and transcribe this data onto spreadsheets. Day 5-7 Presentation and discussion In order to prepare students for science fair projects and to stress the importance of communication in science, each group will construct a poster documenting their question, hypothesis, results and conclusions. It might be useful to discuss posters as a class. Students could discuss which posters were good and what sort of features they had in common. Alternatively, students could discuss features that did not work well (ex-printing that is too small to read from a distance, graphs that do not have labels or titles). During this discussion ask for students input about posters. Ask them for their input on a grading rubric for posters and incorporate this into rubric. Present this rubric to students so they know exactly how they will be evaluated on this project. The last day should be set aside for students to read everyone s posters. Glossary Behavior: animals actions or reactions in response to external or internal stimuli Ethogram: a catalog of behavior patterns of a species. Communication: the cooperative transfer of information from a signaler to a receiver 8 Signaler: produces a signal, which conveys information Receiver: detects signal and uses information to help make a decision about how it should respond 9 Adaptation: a trait that enables an individual to survive or reproduce better than the alternate forms of that trait in a particular environment 8 Alcock, J Animal Behavior, 7 th Ed. Sinauer Associates, Massachusetts. 9 Bradbury J.W. and S. L. Vehrencamp Principles of Animal Communication. Sinauer Associates, Sunderland, Massachusetts, pg 3. 9

10 Natural selection: process that results in evolutionary change via differences in traits that are important for survival and/or reproduction. This leads to differences in the number of offspring (also inheriting such traits) left by individuals of a species Dependent variable: the variable that you are measuring. This is the variable that changes as a result of your independent variable. Independent variable: the variable that you are manipulating. Hypothesis: a possible explanation for how or why something happens. This should be a simple statement, NOT a prediction of what you expect to happen. Prediction: This is what you expect to happen if your hypothesis is correct. Evaluation Formative assessment After showing the behavior video and playing game, begin actual behavior lab with discussion of what students consider to be behavior and what they consider communication between animals o This could be done in small groups where students discuss among themselves and then address the rest of the class with their ideas Further questions for this lab might be focused on why behavior might be important for animals o The purpose of this question would be to determine how easily (or not) students would be able to make the connection between behavior and the ability of an animal to survive and/or reproduce Summative The video worksheet will require students to follow along with video and identify different modes of communication. The ethogram will allow summative assessment of thoroughness and detail in student observations. Following observations, group and class discussion of employing scientific method to study animal communication in crickets, provide students a quiz. This quiz will require students to read a short paragraph and identify the question, hypothesis, predictions, experiment and conclusions. Provide students (possibly in group) with a scenario and ask them to explain what is happening and how they could test their hypotheses. The scenario would be some type of interesting behavioral interaction between two (or more) animals. Students will conduct experiments with field crickets that will ultimately result in a poster. Students will be evaluated according to how well their experiments tested their question, data collection and analysis. In addition their presentation of data and the extent to which these graphs and/or tables illustrate support for (or not) their hypothesis will be evaluated. Finally, they will b evaluated according to how well students brought their experiment back to their original question (whether they supported or refuted their hypothesis or what additional questions need to be addressed). SEE POSTER RUBRIC. 10

11 Extension Data analysis and presentation For older students, enter data into Excel spreadsheets. Students could summarize data using very simple excel functions for mean and distribution. Students could also use the Excel Chart wizard to produce graphs. Some middle school students would be capable of these tasks. Website Resources Insects in the Classroom: A Study of Animal Behavior: Matthews, R.L. et al Insects as teaching tools in primary and secondary education. Annual Review of Entomology 42: The Center for Insect Science Education Outreach This is an excellent site that has many insect fact sheets and lesson plans. Flour Beetles: Hands-on Discovery Lab Age Group: Can be adapted for elementary through high school. Class Time: Initial discussion and preparation one class period (55 minutes). Checking beetles every 3 to 4 weeks will take about 20 minutes. Crickets in the classroom: This page is about using common field and house crickets to teach skills of observation and measurement. The unit also includes basic information on cricket biology and introduces students to the scientific literature html 11