lesson 2.2. ecology

Species Relationships

• Feeding relationships• Autotrophs Vs Heterotrophs• Autotrophs are=things that make their own food– Examples- plants

• Heterotrophs= eat others** for food– Examples- monkeys & humans

"I MUST BE A HETEROTROPH I CAN'T MAKE THESE !!"

Carnivores and Scavengers

• Heterotrophs which eat other heterotrophs– Carnivore= meat eaters– Examples= lion

• Some animals do not kill their own food they are called scavengers– They play a beneficial role in ecosystem.– Clean up dead animals• Examples= turkey vulture

herbivores

• Herbivores eat plants

Omnivores & decomposers

• Omnivores- eat both• Examples= humans & bears

• Fungus is an example of decomposer.

• Decomposers break down and absorb nutrients from dead organisms.

Detritivores

• Detritivores eat “garbage” of ecosystem – organisms that have recently dies, fallen leaves and branches, animal wastes (vulture, bacteria and fungi - decomposers)

Relationships for survival

• Symbiosis– “living together”– Relationship in which there is a close and permanent

association between organisms of a different species

• Commensalism• The predator-prey relationship• Mutualism• Parasitism

Commensalism• One species

benefits and the other is neither helped nor harmed– Barnacles on a

whale• Do not harm or

help whale• Barnacles benefit

because constant moving water source

Predators vs prey

• One organisms hunts another for food– Predators- hunt for food– Prey- organism that predator eats– Predators can be the prey of larger animals

• Population sizes are linked– If # of prey grows or shrinks # of supported

predators does the same

Predator- Prey

• Hunter• Lions• Insect eating birds• Benefit from

relationship

• Hunted• Zebra• Insects• Die from relationship

Predator & prey

• When the # of prey increases the # of predators will increase too because there is more food to support them– Creates a cycle• The larger the animal the larger the life cycle vs smaller

animals–Live longer–Reproduce slower

The changing population size of the prey species controls the population size of the predator species

Predator vs prey

• Fox hunts can kills rabbit

Mutualism

• A symbiotic relationship in which both species benefit– Ants and acacia tree– Flowers and insects– Lichen

– Example: pollination – bees, butterflies, bats, and birds carry pollen to other plants

•

Mutualism • Lichens • An alga and a fungus– depend on each other

and cannot live independently.

• Through photosynthesis, the alga produces the food the lichen requires, while the fungus absorbs vital nutrients and water for it.

Parasitism

• When one organism harms another– A symbiotic relationship in which one organism

derives benefit at the expense of others.– Example• Parasite and host…

– How come parasites only harm not kill host?

Parasite vs Host• Feeds on host• Live on body of host• Depends on host for life

processes• Thrive in crowded areas• Are a density-dependent

limiting factor

• Is feed on• Larger the host the

more parasites it can support

• May become ill or die from parasite

Parasites• Sheep Tick • Carnivorous, feeding on

the blood of various species of birds, reptiles, and mammals, including human beings.

Summary of symbiotic relationships

Relationship Description Harmful vs helpful

Example

Predator & prey One animal eats another

One is helped one is killed

Cat eating a mouse

Parasitism One animals feeds off another

One is helped one is drained of resources or killed

Tick living off a deer

Commensalism One species benefits from another

One is helped one is not phased

Barnacles and a whale

Mutualism Both rely on each other

Both are helped Flower and insect

Competition

• Results from niche overlap (use of the same limited resource by two or more species)– Some animals will fight to the death for their

resources– Some plants species release toxins into the soil

that prevent other species from growing nearby, restricting the space of the other species