Interactions Among Living ThingsThe trap jaw ant closes its mouth the fastest. It closes its mouth in 0.13 milliseconds at speeds of 35 to 64 meters per second! The force created when its jaw snaps shut helps the ant escape danger by either jumping up to 8.3 centimeters high or 39.6 cm sideways.

1.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?

Adaptations

Behaviors and physical characteristics that allow organisms

to live successfully in their environment

Example of adaptations

• Arctic hare: fur changes from gray to white in winter

Niche• The role of an organism in its habitat• What it eats, how it gets food, and what eats

it

Your turn…3. Describe the niche of a squirrel.4. What adaptations might a squirrel have that

make it able to live in its environment?

Interactions Among Living Things

• Competition, Predation, Symbiosis

Competition

If two species occupy the same niche, one of the species might eventually die off because of competition.

Competition: the struggle between organisms to survive as they attempt to use the same limited resources

Predation

Interaction in which one organism kills another for food or nutrients

Predator: the organism that does the killingPrey: the organism that is killed

Your turn…5. Imagine an ideal predator to prey upon a

porcupine. Draw or describe your predator and label its adaptations.

Predator Adaptations

• Cheetah: runs fast for short time• Owls: can hunt at night

Prey adaptations

Skunk: SmellPorcupine: sharp quills

Stopping to think…

6. Two main ways in which organisms interact are ____________ and ________________.

7. Give an example of competition.8. Owls often prey on mice. What adaptations

do you think mice have that help them avoid becoming prey?

Symbiosis

• Any relationship in which two species live closely together and at least one benefits

• 3 kinds are mutualism, commensalism, parasitism

Mutualism

• Both species benefit• Examples: An oxpecker rides and snacks aboard

an impala. The oxpecker eats ticks living on the impala’s ears.

Your turn…9. How does the oxpecker benefit?10. How does the impala benefit?11. Explain how the relationship between a

hummingbird and flower is mutualism?

Commensalism

• One species benefits and the other is neither helped nor harmed

• A bird builds a nest in a tree. The bird gets a place to live while the tree is unharmed.

• This is not very common in nature.

Parasitism

• A relationship that involves one organism living with, on, or inside another organism and harms it

• Parasite: the organism that benefits• Host: organism that it lives on or in• Example: fleas on a dog