CK-12 Life Science
Page 37
Further Reading / Supplemental Links
CK-12 Foundation. High School Biology, Chapter 34, “Animal Behavior.”
Melvin Berger. Dogs Bring Newspapers but Cats Bring Mice: and Other Fascinating Facts about Animal Behavior. Scholastic, 2004.
Paolo Casale and Gian Paolo Faescini. Animal Behavior: Instinct, Learning, Cooperation. Barrons Juveniles, 1999.
http://asci.uvm.edu/course/asci001/behavior.html
http://news.bbc.co.uk/1/hi/sci/tech/2178920.stm
http://news.nationalgeographic.com/news/2005/10/1025_051025_gorillas_tools.html
http://school.discoveryeducation.com/lessonplans/programs/animalinstincts/
http://science.jrank.org/pages/3608/Instinct-Classic-examples-animal-instinct.html
http://www.biology-online.org/dictionary/Insight_learning
http://www.britannica.com/eb/article-48658/animal-behaviour
http://www.discoverchimpanzees.org/behaviors/top.php?dir=Tool_Use&topic=Termite_Fishing
http://www.janegoodall.org/
http://www.keepkidshealthy.com/newborn/newborn_reflexes.html
http://www.nature.com/hdy/journal/v82/n4/full/6885270a.html
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1236726#pbio-0030380-b03
http://www.unmc.edu/Physiology/Mann/mann19.html
Vocabulary
animal behavior
Any way that animals act, either alone or with other animals.
innate behavior
Any behavior that occurs naturally in all animals of a given species.
instinct
Another term for an innate behavior.
reflex behaviors
The only truly innate behaviors in humans, occurring mainly in babies.
learned behavior
Behavior that occurs only after experience or practice.
habituation
Learning to get used to something that is not dangerous after being exposed to it for awhile.
observational learning
Learning by watching and copying the behavior of someone else.
conditioning
Way of learning that involves a reward or punishment.
insight learning
Learning from past experiences and reasoning.
Points to Consider
Did you ever watch a long line of ants marching away from their ant hill? What were they doing? How were they able to work together? What explains group behaviors such as this?
Lesson 15.2: Types of Animal Behavior
Lesson Objectives
List ways that animals communicate.
Describe social behavior in animals.
Explain the purpose of mating behavior.
Describe how animals defend their territory.
Identify animal behaviors that occur in cycles.
Check Your Understanding
What is an animal?
Give examples of a wide variety of animals.
List some "behaviors" animals, such as spiders and rabbits, have in common.
Introduction
What is reproduction? (Reproduction is the production of offspring. Animals reproduce asexually or sexually. Reproduction is related to fitness because fitness depends in part on the ability to reproduce. Do all animals talk to each other? Probably not, but many do communicate. Like human beings, many other animals live together in groups. Some insects, including ants and bees, are well known for living in groups. In order for animals to live together in groups, they must be able to communicate with each other. Animal communication, like most other animal behaviors, increases fitness. Fitness is the ability to survive and have offspring. Communication increases fitness by helping animals find food, defend themselves from predators, mate, and care for offspring.
Communication
What does the word communication make you think of? Talking on a cell phone? Texting? Writing? Those are just a few of the ways that human beings communicate. Most other animals also communicate. Communication is any way that animals share information, and they do this in many different ways.
Ways That Animals Communicate
Some animals communicate with sound. Most birds communicate this way. Birds use different calls to warn other birds of danger or to tell them to flock together. Many other animals also use sound to communicate. For example, monkeys use warning cries to tell other monkeys in their troop that a predator is near. Frogs croak to attract female frogs as mates. Gibbons use calls to tell other gibbons to stay away from their area.
Another way some animals communicate is with sight. By moving in certain ways or “making faces,” they show other animals what they mean. Most primates communicate in this way. For example, a male chimpanzee may raise his arms and stare at another male chimpanzee. This warns the other chimpanzee to keep his distance. The chimpanzee in Figure below may look like he is smiling. However, he is really showing fear. He is communicating to other chimpanzees that he will not challenge them. Look at the peacock in Figure below. Why is he raising his beautiful tail feathers? He is also communicating. He is showing females of his species that he would be a good mate.
All of the animals pictured here are busy doing something important. Read about what each animal is doing then think about why the animal is behaving that way. These are just a few of the many ways that animals behave.
Figure 15.20
This chimpanzee is communicating with his face. His expression is called a fear grin. It tells other chimpanzees that he is not a threat.
Figure 15.21
This peacock is using his tail feathers to communicate. What is he saying?
Some animals communicate with scent. They secrete chemicals that other animals of their species can smell or detect in some other way. Ants secrete many different chemicals. Other ants detect the chemicals with their antennae. This explains how ants are able to work together. The different chemicals that ants secrete have different meanings. Some of the chemicals signal all the ants in a group to come together. Other chemicals warn of danger. Still other chemicals mark trails to food sources. When an ant finds food, it marks the trail back to the nest by secreting a chemical on the ground. Other ants follow the chemical trail to the food.
Many other animals also use chemicals to communicate. You have probably seen male dogs raise their leg to urinate on a fire hydrant or other object. Did you know that the dogs were communicating? They were marking their area with a chemical in their urine. Other dogs can smell the chemical. The scent of the chemical tells other dogs to stay away.
Human Communication
Like other animals, humans communicate with one another. They mainly use sound and sight to share information. The most important way that humans communicate is with language. Language is the use of symbols to communicate. In human languages, the symbols are words. They stand for many different things. Words stand for things, people, actions, feelings, or ideas. Think of several common words. What does each word stand for?
Another important way that humans communicate is with facial expressions. Look at the faces of the young children in Figure below. Can you tell from their faces what the children are feeling? Humans also use gestures to communicate. What are people communicating when they shrug their shoulders? When they shake their head? These are just a few examples of the ways that humans share information without using words.
Figure 15.22
What does this girls face say about how she is feeling?
Social Behavior
Why is animal communication important? Without it, animals would not be able to live together in groups. Animals that live in groups with other members of their species are called social animals. Social animals include many species of insects, birds, and mammals. Specific examples of social animals are ants, bees, crows, wolves, and humans. To live together with one another, these animals must be able to share information.
Highly Social Animals
Some species of animals are very social. In these species
, members of the group depend completely on one another. Different animals within the group have different jobs. Therefore, group members must work together for the good of all. Most species of ants and bees are highly social animals.
Ants, like those in Figure below, live together in large groups called colonies. A colony may have millions of ants. All of the ants in the colony work together as a single unit. Each ant has a specific job. Most of the ants are workers. Their job is to build and repair the colony’s nest. Worker ants also leave the nest to find food for themselves and other colony members. The workers care for the young, as well. Other ants in the colony are soldiers. They defend the colony against predators. Each colony also has a queen. Her only job is to lay eggs. She may lay millions of eggs each month. A few ants in the colony are called drones. They are the only male ants in the colony. Their job is to mate with the queen.
Figure 15.23
The ants in this picture belong to the same colony. They have left the colonys nest to search for food.
Honeybees and bumblebees also live in colonies. A colony of honeybees is shown in Figure below. Each bee in the colony has a particular job. Most of the bees are workers. Young worker bees clean the colony’s hive and feed the young. Older worker bees build the waxy honey comb or guard the hive. The oldest workers leave the hive to find food. Each colony usually has one queen that lays eggs. The colony also has a small number of male drones. They mate with the queen.
Figure 15.24
All the honeybees in this colony work together. Each bee has a certain job to perform. The bees are gathered together to fly to a new home. How do you think they knew it was time to gather together?
Cooperation
Ants, bees, and other social animals must cooperate. Cooperation means working together with others. Members of the group may cooperate by sharing food. They may also cooperate by defending each other. Look at the ants in Figure below. They show clearly why cooperation is important. A single ant would not be able to carry this large insect back to the nest to feed the other ants. With cooperation, the job is easy.
Figure 15.25
These ants are cooperating. By working together, they are able to move this much larger insect prey back to their nest. At the nest, they will share the insect with other ants that do not leave the nest.
Animals in many other species cooperate. For example, lions live in groups called prides. A lion pride is shown in Figure below. All the lions in the pride cooperate. Male lions work together to defend the other lions in the pride. Female lions work together to hunt. Then they share the meat with other pride members.
Figure 15.26
Members of this lion pride work together. Males cooperate by defending the pride. Females cooperate by hunting and sharing the food.
Meerkats are small mammals that live in Africa. They also live in groups and cooperate with one another. For example, young female meerkats act as babysitters. They take care of the baby meerkats while their parents are away looking for food.
Mating Behavior
Some of the most important animal behaviors involve mating. Mating is the pairing of an adult male and female to produce young. Adults that are most successful at attracting a mate are most likely to have offspring. Traits that help animals attract a mate and have offspring increase their fitness. If the traits are controlled by genes, they will become more common in the species through natural selection.
Courtship Behaviors
In many species, females choose the male they will mate with. For their part, males try to be chosen as mates. They show females that they would be a better mate than the other males. To be chosen as a mate, males may perform courtship behaviors. These are special behaviors that help attract a mate. Male courtship behaviors get the attention of females and show off a male’s traits. Different species have different courtship behaviors. Remember the peacock raising his tail feathers in Figure 1b? This is an example of courtship behavior. The peacock is trying to impress females of his species with his beautiful feathers.
Another example of courtship behavior in birds is shown in Figure below. This bird is called a blue-footed booby. He is doing a dance to attract a female for mating. During the dance, he spreads out his wings and stamps his feet on the ground. You can watch a video of a blue-footed booby doing his courtship dance at: http://www.travelpod.com/travel-photo/harryandnorah/the_other_way/1199840760/blue-footed-booby-courting-dance.avi/tpod.html.
Figure 15.27
This blue-footed booby is a species of sea bird. The male pictured here is doing a courtship dance. He is trying to attract a female for mating.
Courtship behaviors occur in many other species. For example, males in some species of whales have special mating songs to attract females as mates. Frogs croak for the same reason. Male deer clash antlers to court females. Male jumping spiders jump from side to side to attract mates. To see a video of a jumping spider courting a mate, go to: http://video.aol.com/video-detail/courtship-and-mating-of-the-jumping-spider-lyssomanes-viridis-araneae-salticidae/2837652909.
Courtship behaviors are one type of display behavior. A display behavior is a fixed set of actions that carries a specific message. Although many display behaviors are used to attract mates, some display behaviors have other purposes. For example, display behaviors may be used to warn other animals to stay away, as you will read below.
Caring for the Young
In most species of birds and mammals, one or both parents care for their offspring. Caring for the young may include making a nest or other shelter. It may also include feeding the young and protecting them from predators. Caring for offspring increases their chances of surviving. When parents help their young survive, they increase their own fitness.
Birds called killdeers have an interesting way to protect their chicks. When a predator gets too close to her nest, a mother killdeer pretends to have a broken wing. The mother walks away from the nest holding her wing as though it is injured. This is what the killdeer in Figure below is doing. The predator thinks she is injured and will be easy prey. The mother leads the predator away from the nest and then flies away.
Figure 15.28
This mother killdeer is pretending she has a broken wing. She is trying to attract a predators attention in order to protect her chicks. This behavior puts her at risk of harm. How can it increase her fitness?
In most species of mammals, parents also teach their offspring important skills. For example, meerkat parents teach their pups how to eat scorpions without being stung. A scorpion sting can be deadly, so this is a very important skill. Teaching the young important skills makes it more likely that they will survive.
Defending Territory
Some species of animals are territorial. This means that they defend their area. The area they defend usually contains their nest and enough food for themselves and their offspring. A species is more likely to be territorial if there is not very much food in their area.
Animals generally do not defend their territory by fighting. Instead, they are more likely to use display behavior. The behavior tells other animals to stay away. It gets the message across without the need for fighting. Display behavior is generally safer and uses less energy than fighting.
Male gorillas use display behavior to defend their territory. They pound on their chests and thump the ground with their hands to warn other male gorillas to keep away from their area. The robin in Figure below is also using display behavior to defend his territory. He is displaying his red breast to warn other robins to stay away.
Figure 15.29
The red breast of this male robin is easy to see. The robin displays his bright red chest to defend his territory. It warns other robins to keep out of his area.
Some animals deposit chemicals to mark the boundary of their territory. This is why dogs urinate on fire hydrants and other objects. Cats may also mark their territory by depositing chemicals. They have scent glands in their face. They deposit chemicals by rubbing their face agains
t objects.
Cycles of Behavior
Many animal behaviors change in a regular way. They go through cycles. Some cycles of behavior repeat each year. Other cycles of behavior repeat every day.
Yearly Cycles
An example of a behavior with a yearly cycle is hibernation. Hibernation is a state in which an animal’s body processes are slower than usual and its body temperature falls. An animal uses less energy than usual during hibernation. This helps the animal survive during a time of year when food is scarce. Hibernation may last for weeks or months. Animals that hibernate include species of bats, squirrels, and snakes.
Most people think that bears hibernate. In fact, bears do not go into true hibernation. In the winter, they go into a deep sleep. However, their body processes do not slow down very much. Their body temperature also remains about the same as usual. Bears can be awakened easily from their winter sleep.
Another example of a behavior with a yearly cycle is migration. Migration is the movement of animals from one place to another. Migration is an innate behavior that is triggered by changes in the environment. For example, animals may migrate when the days get shorter in the fall. Migration is most common in birds, fish, and insects. In the Northern Hemisphere, many species of birds, including robins and geese, travel south for the winter. They migrate to areas where it is warmer and where there is more food. They return north in the spring. A flock of migrating geese is shown in Figure below.