Ch. 14.3 Ms. De Los Rios 7th Grade Essential Question: How Do Living Things Affect One Another? How Do Adaptations Help an Organism Survive? What Are Competition and Predation? What are Three Types of Symbiosis? Interactions Among Living Things Pgs. 490-499
Vocabulary • Natural Selection- The process by which organisms that are best adapted to their environment are most likely to survive and reproduce • Adaptation- An inherited behavior or physical characteristic that helps an organism survive and reproduce in its environment • Niche- How an organism makes its living and interacts with the biotic and abiotic factors in its habitat • Competition- The struggle between organisms to survive as they attempt to use the same limited resources in the same place, at the same time. • Parasite- The organism that benefits by living with, on, or in a host in a parasitism interaction. • Host-An organism that a parasite lives with, in, or on, and provides a source of energy or a suitable environment for the parasite to live.
Vocabulary • Symbiosis- Any relationship in which two species live closely together and that benefits at least one of the species. • Mutualism-A type of symbiosis in which both species benefit from living together. • Commensalism- A type of symbiosis between two species in which one species benefits and the other species is neither helped or harmed. • Parasitism- A type of symbiosis in which one organism lives with, on or in a host and harms it. • Predation-An interaction in which one organism kills another for food or nutrients. • Predator-The organism that does the killing in a predation interaction. • Prey- An organism that is killed and eaten by another organism in a predation interaction.
My Planet Diary pg. 490 • Predator Power • What predator can close its jaws the fastest? You might think it is a lion or a shark, but you would be wrong. It is the trap-jaw ant that has the fastest predatory strike in the animal kingdom. The trap-jaw ant closes its mouth around its prey in 0.13 milliseconds at speeds of 35 to 64 meters per second! The force created when its jaw snaps shut also helps the ant escape danger by either jumping up to 8.3 centimeters high or 39.6 centimeters sideways. • How does the trap-jaw ant’s adaptation • help it avoid becoming the prey of another organism? • 2. What are some adaptations that other • predators have to capture prey?
How Do Adaptations help an Organism Survive? Pg. 491 • As day breaks, a sound comes from a nest tucked in a branch of a saguro cactus. Two young red-tailed hawks are preparing to fly. Farther down the stem, a tiny elf owl peeks out of its nest in a small hole. A rattlesnake slithers around the base of the saguaro, looking for breakfast. Spying a shrew, the snake strikes it with needlelike fangs. The shrew dies instantly.
Natural Selection Pg. 492 • Individuals with characteristics that • Are best suited for their environment tend to • Survive and pass on these • Characteristics to their offspring • through a process called • natural selection. • The behaviors and characteristics that allow organisms to live successfully in their environments are called adaptations. • Individuals with characteristics that are poorly suited for their environment are less likely to survive and reproduce. Over time, poorly suited characteristics may disappear from the species. If a species cannot adapt to changes in its environment, the entire species can disappear from Earth and become extinct.
Saguaro Community fig. 1 pg. 491 DESCRIBE Circle two examples of how organisms interact in this scene. Describe each one.
Niche Pg. 492 • An organism has a role, or niche, in its habitat. The organisms in the saguaro community have adaptations that result in specific roles. The role an organism has in its habitat is called its niche. A niche includes the type of food the organism eats and how it gets this food. A niche also includes when and how the organism reproduces and the physical conditions that it needs to survive. Each organism has unique characteristics that affect the organism’s ability to survive and reproduce in its environment.
Organisms occupy many niches in an environment. Niches • Apply it! • Identify- List two abiotic factors in the picture. • Interpret Diagrams- • Describe the niche of the squirrel in the picture. • 3. Make generalizations- What adaptations might the squirrel have that make it able to live in this environment.
Assess Your Understanding pg. 492 • 1a. Define – Adaptations are the __________________ and ______________________ characteristics that allow organisms to live successfully in their environments. • b. Explain - How are a snake’s sharp fangs an adaptation that help it survive in the saguaro community? • __________________________________________________________________________________________________________________ • I get it! Now I know that adaptations are __________________________________________________________________________________________________________________
What is Competition? Pg. 493 • Two major types of interactions among organisms are competition and predation. • Competitionis the • struggle between organisms • to survive as they attempt • to occupy the same niche • and use the same limited • resources. • Organisms that share the same habitat often have adaptations that reduce competition. • For example, three types of birds can each get food from different parts of the same tree.
Predation pg. 494 • Predation An interaction is which one organism kills another for food. • The predator Thespecies that hunts and kills the prey. • The prey The species that is hunted or killed. • -Predators have adaptations that help them catch prey. • -Organisms have adaptations that help them avoid becoming prey. • Predators can affect population size. If there are too many predators in an area, the number of prey will decrease. As a result, there is less food for predators and the predator population will go down too.
Niche and Competition Fig. 2 pg. 493 • Each of these warbler species occupies a very specific location in its habitat. By feeding on insects in different areas of the tree, the birds avoid competing for food and are able to live together. • Predict- What could happen if these warbler species fed in the same location on the tree? • List- For what resources do the tree and the grass compete?
Predator Adaptations pg. 495 • Predators have adaptations that help them catch and kill their prey. A cheetah can run very fast for a short time, enabling it to catch its prey. Some predators, such as owls and bats, have adaptations that enable them to hunt at night when their prey are active. Fig. 4 pg. 494 A jellyfish’s tentacles contain a poisonous substance that paralyzes tiny water animals. The sundew is a plant that is covered with sticky bulbs on stalks. When a fly lands on a bulb, it remains snared in the sticky goo while the plant digests it. Imagine an ideal predator to prey on a porcupine. Draw or describe your predator and label its adaptations.
Prey Adaptations pg. 495 False Coloring- Predators may be confused by a false eyespot and attack the wrong end of the animal. This allows the animal to get away safely. • Organisms have manyadaptationsthat help them avoid becoming prey.
Prey Adaptations – Warning Coloring • Many brightly colored animals are poisonous and their bright colors warn predators not to eat them!
Mimicry • Animals often mimic the coloring, shape, and swimming style of venomous animals to discourage predators.
Protective Covering • Some animals have a hard shell covering to prevent being eaten by predators.
Camouflage • Some animals and insects, use coloring to help them blend into their surroundings.
Predator-Prey Interactions On Isle Royale, an island in Lake Superior, the populations of wolves (the predator) and moose (the prey) rise and fall in cycles. Use the graph to answer the questions. Read Graphs- What variable Is plotted on the x-axis? What two variables are plotted on the y-axis?______________________ 2. Interpret Data- How did the moose Population change between 2002 and 2007 2007? What happened to the wolf population from 2003 through 2006?________________ _____________________________________ 3. Draw conclusions- How might the change in moose population have led to the change in the wolf population? ___________________ _____________________________________ 4. Explain- What adaptations does a wolf have that makes it a successful predator? _______ _____________________________________ 5. Predict- How might disease in the wolf population one year affect the moose population the next year?_________________
Assess Your Understanding pg. 496 • 2a. Review - Two main ways in which organisms interact are ___________________ and _____________________. • b. Describe – Give an example of competition. Explain your answer. • ______________________________________________________________________________________________________________ • c. Apply concepts – Owls often prey on mice. What adaptations do you think the mice have that help them avoid becoming prey? • ______________________________________________________________________________________________________________ • I get it! Now I know that competition and predation • _______________________________________________________________________________________________________________
What Are The Three Types Of Symbiosis?pg. 497 • The 3 main types of symbiotic relationships are • 1. Mutualism • 2 2. Commensalism • 3. Parasitism
Mutualism • Mutualism is a relationship in which both species benefit. When an oxpecker eats ticks living on the impala’s ear, both organisms benefit.
Commensalism • Commensalism is a relationship in which one species benefits and the other species is not affected, such as a bird’s nest in a tree.
Parasitism • Parasitism is a relationship in which one organism benefits and the other organism is harmed. The organism that benefits is called a parasite. The organism that is harmed is called the host. Fish lice are parasites that feed on the blood of a host fish.
Fig. 7 pg. 498 List the names of the parasites and the hosts.
Assess Your Understanding pg. 499 • 3a. Compare and contrast – Identify two types of interactions among organisms and then compare and contrast them. • __________________________________________________________________________________________________________________ • b. How do living things affect one another? • __________________________________________________________________________________________________________________ • I get it! Now I know that the three types of symbiosis differ in • __________________________________________________________________________________________________________________