Introduction: (Initial Observation)
I have heard crickets chirp many times, and I have always had questions about it. I wish I could understand them and find out what they are talking about with such loud sound and excitement. I noticed that they often chirp at night, and sometimes they chirp more than others. I have been wondering why they do this? Is it some kind of conversation among crickets?
Are they warning each other about danger? Does it mean they are happy? scared? hungry? cold? hot? Is chirping an indication of being male or female? Does chirping have anything to do with the wind? the moon? temperature? darkness?
This project is an opportunity to study crickets and find out about the factors that affect chirping of crickets (gender, time of day, weather temperature).
Field and house crickets are ideal subjects for practicing observation, measurement, hypothesis formation and testing, and a variety of skills important in science. Crickets can be easily collected in the field or they can be purchased from various vendors. Crickets perform some very interesting behaviors and use sound to manipulate the behavior of others. Cricket behavior is easy to observe and the entire exercise is inexpensive.
First gather information about crickets, their life cycle, reproduction, and varieties. Find out how you can identify males and females. Read books, magazines, or ask professionals who might know in order to learn about the factors that may affect the rate at which crickets chirp.
If you search the Internet, search for keywords such as “Cricket habitat”, “Cricket life cycle”, “Crickets feed”, ….
The following are samples of information that you may find.
Cricket is a common name of slender, chirping, hopping insects – forming the family Gryllidae in the order Orthoptera. Most crickets have long antennae, muscular hind legs for jumping, and two pairs of fully developed wings. In some subfamilies the wings are reduced or absent. In most subfamilies the males have song-producing, or stridulatory, organs on the front wings.
Where can I find crickets?
Crickets can be collected from a field or purchased from pet stores. You can also buy crickets online. Just search for “Order Cricket”. If you buy crickets, you must know that transferring crickets from their shipping container into their permanent housing can be at best a “tricky” task and at worst an exercise in mass escape. Even a few escapees should be avoided at all costs as they hide all over the house, dining on your designer carpet and serenading you all night when you would much rather be asleep.
This is a sample instructions for transferring crickets.
Carefully slice open the box and, without opening it, place it into a large clear plastic bag. Open the box and shake out both the crickets and dividers as they are each removed. Make sure all of the crickets are off of the egg crate dividers and remove the dividers from the bag as you proceed. Shake the crickets out of the box, making sure all of them are out, and immediately take it outside your house or apartment.
Put pieces of egg crate into your clean cricket housing container and attach the top.
Now, position the opening of the bag through the opening between your lid and the container. Carefully slide the crickets forward to the neck of the bag, shaking them into the container. Once the bag is empty, remove it carefully to shake off any clinging crickets, and… success! All crickets transferred without any escapes!
Cricket Care and Feeding
Crickets have long been the symbol of good luck in many cultures. By following the easy instructions below, you will be successful in keeping your crickets alive and healthy.
Your first task is to set up a housing container for the crickets. Suitable containers include glass aquariums (the 10 gallon size works well), wide-mouth glass jars, large plastic containers or 5-gallon buckets. Large garbage cans have been found successful for larger colonies. You will need an aluminum screen cover for the container. Don’t use fiberglass, as the crickets will chew through them.
Your container should be of a size to provide adequate space for your crickets to spread out comfortably. Do not overcrowd them, as overcrowding is the major cause of excessive death in crickets. They will be fine if they are not required to be “stacked up” in their new home. Each cricket needs to be able to sit directly on some surface rather than on another cricket.
We recommend that you place no substrate in your cricket container as it becomes much more difficult to keep the crickets clean. You will find that using no substrate reduces the possibility of offensive odors considerably. However, if you wish to use a substrate, sand, wood shavings (available in most pet stores) or peat moss all make a suitable substrate.
Place egg crate dividers, paper towel or toilet paper rolls or similar hiding places into the container and follow the directions for Transferring Crickets from Shipping box to their Storage Container.
Food and Feeding
House crickets will eat most edible foods such as stale bread, poultry mash, cornmeal, powdered dog or cat food, tropical fish flakes, pond fish pellets, rabbit chow and many other similar foods.
Feeding crickets correctly is important because they require a high protein diet in order to stay healthy. Without an adequate diet, they will prey upon each other.
To provide a balanced diet, supplement the dry food with raw vegetable or fruit scraps such as slices of apple, banana, or orange, plus greens such as lettuce or cabbage. The food should be placed in a small, shallow plastic container, periodically discarding any uneaten portions on a regular basis to insure cleanliness and freedom from mold.
Do not forget to supply your crickets with water! Place moist cotton or pieces of a wet sponge in a shallow dish. Make sure there is no standing water in your water dish, as small crickets can easily drown in even the smallest amount of standing water. Be sure to wash the water dish and wash or replace the sponges at least once a week (twice is better). Unwashed water dishes are one of the leading causes of offensive odors in your cricket house.
Crickets are clean insects and must be kept clean and dry. Your success with them will be reflected by the care you have given them. We suggest that once a week you scrape or sweep your container(s). Regardless of the number of crickets in your container(s), you will find it simple to clean around them.
Crickets thrive at temperatures higher than those in the average house. They prefer 80-90 degrees Fahrenheit (26-32 degrees Celsius), however they seem to live longer at somewhat lower temperatures – something to keep in mind if you want to keep an excess of crickets alive as long as possible.
Smaller crickets require warmer temperatures. Pinheads do best at 88-92 degrees Fahrenheit, with 1/2 to 3/4 inch doing best at 80-92 degrees Fahrenheit, and adults at 75-85 degrees Fahrenheit.
Cricket nymphs (smaller than pinheads) held at 80 degrees Fahrenheit require up to 60-65 days to mature, while those kept at 90 degrees Fahrenheit require only 30-35 days to complete their development.
Crickets are very susceptible to insecticides! Avoid any type of insecticides such as sprays, “no-pest strips” or anything that might give off fumes – even if not in the same room.
General Cricket Information
Crickets begin life as eggs, hatch into nymphs which then mature into adults. When the nymphs grow too large for their exoskeletons which are made of chitin, they molt a series of 5 times. After the final molt, the wings are released and the male can then “chirp”. Crickets chirp by rubbing their two upper wings together, but only the male has the special rough vein on its wing that makes the sound louder when the one wing is rubbed against the other.
Male crickets grow to approximately 1 inch long and females sometimes are even larger.
By searching the Internet, I learned that many others have also studied cricket chirps. The following are excerpts of their reports.
A cricket chirps faster when the weather is warmer. The number of chirps per minute is approximately 7 times the temperature (in degrees Celsius) and then take 20°C. How fast would it chirp if the temperature was 30°C? What would the temperature need to be for it to chirp at 150 chirps per minute? source
Counting Cricket Chirps to Estimate Temperature
Crickets are sensitive to changes in air temperature, and chirp at faster rates as the temperature rises. It is possible to use the chirps of the male snowy tree cricket, common throughout the United States, to gauge temperature.
The formula for this is to count the number of chirps in 15 seconds and add 39 to calculate the temperature (degrees Fahrenheit.) If there are 30 chirps in 15 seconds, the temperature should be about 69 degrees F. This formula is said to be accurate within one degree. A variation is to count the chirps in 13 seconds, and add 40.
“Cricket thermometers,” Field & Stream, July 1993, Vol. 98 Issue 3, p21.
Anatomy: House crickets are about 3/4- to an inch long and yellow-brown or straw-colored with three dark bands across the top of the head. The house cricket has long, slender antennae that are much longer than the body. The wings on adult crickets lay flat on the back and are bent down on the sides. Adult female crickets have a long slender, tube-like structure (ovipositor) projecting from their abdomen which they use to lay eggs. Both males and females have to antenna-like structures (called cerci) that are attached to the sides of the tips of the abdomen. Nymphs look like the adults but are smaller with less developed wings.
What do you want to find out? Write a statement that describes what you want to do. Use your observations and questions to write the statement.
Many different factors can be tested for their effect on chirping of crickets. In this project I will test the effect of temperature.
The purpose of this project is to study the effect of temperature on the rate in which crickets chirp.
Based on your gathered information, make an educated guess about what types of things affect the system you are working with. Identifying variables is necessary before you can make a hypothesis.
Crickets chirp more frequently if the weather is warmer. My hypothesis is based on my gathered information and personal observation. I have noticed that I often hear chirping of crickets most often in the summer time when the temperature is relatively higher.
Design an experiment to test each hypothesis. Make a step-by-step list of what you will do to answer each question. This list is called an experimental procedure. For an experiment to give answers you can trust, it must have a “control.” A control is an additional experimental trial or run. It is a separate experiment, done exactly like the others. The only difference is that no experimental variables are changed. A control is a neutral “reference point” for comparison that allows you to see what changing a variable does by comparing it to not changing anything. Dependable controls are sometimes very hard to develop. They can be the hardest part of a project. Without a control you cannot be sure that changing the variable causes your observations. A series of experiments that includes a control is called a “controlled experiment.”
Experiment: The effect of temperature on the rate in which crickets chirp
Introduction: In this experiment you will test the effect of temperature to see how temperature affects the rate in which a cricket chirps.
- Separate a male adult cricket. Place it in a separate cage away from other crickets that you may have.
- Place a room thermometer in the cage so you can read the cage temperature.
- Transfer the cricket cage to a small cold dark room or cabinet.
- Turn on the heat so the room temperature starts to rise.
- Listen to chirping. It may take a while for chirping to start.
- When chirping starts, count the number of chirps per minute and then immediately read and record the cage temperature.
- Let some time pass so the room gets warmer.
- Count the number of chirps per minute again and repeat reading and recording the temperature.
- Record your results in a table like this:
|Temperature||Chirps per minute|
- Repeat this experiment 3 times. Make a separate results table for each experiment.
- Use your results tables to draw three different graphs in three different colors on the same paper. You may alternatively merge three tables and draw only one line graph to show all results
Changing the environment temperature must be done gradually. In a period of 2 to 3 hours you should be able to try temperatures from cold to warm. Instead of a room or cabinet, you may use a carton box. A few packs of ice (in a plastic bag) inside or under the box can make it cold. A desk lamp faced to the box or kettle of hot water placed in the box can increase the temperature. Some thermometers may be installed in a way that the sensor will enter the box, while the display part stays out for an easy reading. Do not cause distractions that may cause crickets to stop chirping. If you use an electric heater, care must be taken to prevent fire.
Experiment 2: Can chirping rate be used to measure the temperature?
Introduction: In this experiment you will calculate the temperature somewhere outdoors by counting the number of chirps of a cricket. You will then compare it with the real temperature shown by a thermometer.
Scratch piece of paper
Thermometer (if you’d like to check your estimate)
Activity: Estimate the temperature by listening to a cricket chirp!
- Find an area outside during the evening (as crickets usually chirp at night) where you can easily hear crickets chirps. Your backyard might be a great place…this is also a good activity when you go camping.
- Record the amount of cricket chirps you hear in 15 seconds by using your stopwatch. Add this number to 48.
- This is the outside temperature in Fahrenheit. Check your estimate with the thermometer. How close are you? (Or actually, how close is the cricket?)
You can make an equation to represent a cricket’s chirps. If “C” is the amount of chirps you hear in 15 seconds then…
C + 48 = temperature in F (Fahrenheit)
You could use this equation to calculate a good evening to wear shorts or the right time to wear a jacket.
Exploration Beyond: If you didn’t get the same temperature as your thermometer when you were doing this experiment, what factors could be involved? Is it possible that the location where the cricket is chirping is warmer or cooler than where you are standing?
You may try to test other factors; however, temperature is the only factor that affects the rate of chirping. For example if you try testing gender, you will notice that females do not chirp at all and only males crickets chirp.
You may try different light intensities and keep the temperature constant. You will most likely conclude that crickets do not chirp when it is bright out. They only chirp in the dark or very dim light.
Materials and Equipment:
This is what you need to determine the effect of temperature on the number of chirps.
Scratch piece of paper
Thermometer (if you’d like to check your estimate)
Results of Experiment (Observation):
Experiments are often done in series. A series of experiments can be done by changing one variable a different amount each time. A series of experiments is made up of separate experimental “runs.” During each run you make a measurement of how much the variable affected the system under study. For each run, a different amount of change in the variable is used. This produces a different amount of response in the system. You measure this response, or record data, in a table for this purpose. This is considered “raw data” since it has not been processed or interpreted yet. When raw data gets processed mathematically, for example, it becomes results.
Others experimented and following are some results:
Have you ever walked outside in a quiet evening to hear a tiny chorus of crickets’ chirping? You are most likely hearing the common field cricket. Male crickets have organs that produce sound on their front wings. Male crickets rub their wings together to produce that chirp you hear at night. But they are not just chirping to make the quiet night go by. Male crickets are trying to attract females.
Scientists have noticed a very unusual relationship between crickets’ chirpings and temperature. On very cold days, there are large intervals between cricket chirps. That means the space between each cricket chirp is long, and so the chirps are not very frequent. Why do you think it is like this on colder days? On warmer days, the interval between each cricket chirp is smaller and so the chirps are heard frequently.
Scientists are able to relate the chirping of crickets and temperature of their environment mathematically. The amount of cricket chirps heard (in fifteen seconds) plus 48 is the approximate temperature of the cricket’s environment in degrees Fahrenheit!
That means you can go outside in the evening and get an approximate estimate of the temperature without using a thermometer or flipping to the Weather Channel! Just listen to the crickets.
Counting the chirps per minute is not considered a calculation. Trying to find a relation between the temperature and number of chirps however may require some calculations.
Summary of Results:
Summarize what happened. This can be in the form of a table of processed numerical data, or graphs. It could also be a written statement of what occurred during experiments.
It is from calculations using recorded data that tables and graphs are made. Studying tables and graphs, we can see trends that tell us how different variables cause our observations. Based on these trends, we can draw conclusions about the system under study. These conclusions help us confirm or deny our original hypothesis. Often, mathematical equations can be made from graphs. These equations allow us to predict how a change will affect the system without the need to do additional experiments. Advanced levels of experimental science rely heavily on graphical and mathematical analysis of data. At this level, science becomes even more interesting and powerful.
Using the trends in your experimental data and your experimental observations, try to answer your original questions. Is your hypothesis correct? Now is the time to pull together what happened, and assess the experiments you did.
Related Questions & Answers:
What you have learned may allow you to answer other questions. Many questions are related. Several new questions may have occurred to you while doing experiments. You may now be able to understand or verify things that you discovered when gathering information for the project. Questions lead to more questions, which lead to additional hypothesis that need to be tested.
If you did not observe anything different than what happened with your control, the variable you changed may not affect the system you are investigating. If you did not observe a consistent, reproducible trend in your series of experimental runs there may be experimental errors affecting your results. The first thing to check is how you are making your measurements. Is the measurement method questionable or unreliable? Maybe you are reading a scale incorrectly, or maybe the measuring instrument is working erratically.
If you determine that experimental errors are influencing your results, carefully rethink the design of your experiments. Review each step of the procedure to find sources of potential errors. If possible, have a scientist review the procedure with you. Sometimes the designer of an experiment can miss the obvious.
List of References