Post on 29-Jun-2015
The three major types of interaction among organisms in an ecosystem are
competition
predationsymbiosis
• Resources are the things that organisms obtain from their environment in order to survive.
• They include food, water and shelter.
• Some resources are limited.
Sunday, March 24, 13
Limiting Factors• Anything that restricts or controls the number of
individuals in a population• Includes biotic (living) and abiotic (nonliving)
features of the ecosystem
Sunday, March 24, 13
• All living things compete for– Food and Water– Habitat – Reproduction
• Competition limits population growth• Competition caused by population growth affects
many organisms, including humans
the struggle between organisms that attempt to use the same limited resources
Competition
Sunday, March 24, 13
Predator - PreyPredators are consumers that capture and eat other consumers, called prey
generally have traits that enhance their ability to capture prey, such as fast speed, keen eyesight, and sharp teeth.
Sunday, March 24, 13
Prey
• Prey have traits that help them avoid being captured, such as the
• ability to escape quickly or to hide in the environment.
Sunday, March 24, 13
PreyAny animal which is hunted and killed by
another animal for food is prey.
• Prey have traits that help them avoid being captured, such as the
• ability to escape quickly or to hide in the environment.
Sunday, March 24, 13
PreyAny animal which is hunted and killed by
another animal for food is prey.
• Prey have traits that help them avoid being captured, such as the
• ability to escape quickly or to hide in the environment.
Sunday, March 24, 13
PreyAny animal which is hunted and killed by
another animal for food is prey.
Predator
• Prey have traits that help them avoid being captured, such as the
• ability to escape quickly or to hide in the environment.
Sunday, March 24, 13
PreyAny animal which is hunted and killed by
another animal for food is prey.
Predator
• Prey have traits that help them avoid being captured, such as the
• ability to escape quickly or to hide in the environment.
Sunday, March 24, 13
PreyAny animal which is hunted and killed by
another animal for food is prey.
Predator
Prey
• Prey have traits that help them avoid being captured, such as the
• ability to escape quickly or to hide in the environment.
Sunday, March 24, 13
PreyAny animal which is hunted and killed by
another animal for food is prey.
Predator
Prey
• Prey have traits that help them avoid being captured, such as the
• ability to escape quickly or to hide in the environment.
Sunday, March 24, 13
0
20.00
40.00
60.00
80.00
1900 1905 1910 1915 1920
Hares and Lynx PopulationsN
umbe
r of p
elts
in th
ousa
nds
Year
Hares (x1000) Lynx(x1000)
Sunday, March 24, 13
Food Chains• The energy flow from one trophic level to
the other is know as a food chain
Sunday, March 24, 13
Food Chains• The energy flow from one trophic level to
the other is know as a food chain• A food chain is simple and direct
Sunday, March 24, 13
Food Chains• The energy flow from one trophic level to
the other is know as a food chain• A food chain is simple and direct• It involves one organism at each trophic
level
Sunday, March 24, 13
Food Chains• The energy flow from one trophic level to
the other is know as a food chain• A food chain is simple and direct• It involves one organism at each trophic
level– Primary Consumers – eat producers
Sunday, March 24, 13
Food Chains• The energy flow from one trophic level to
the other is know as a food chain• A food chain is simple and direct• It involves one organism at each trophic
level– Primary Consumers – eat producers– Secondary Consumers – eat the
primary consumers
Sunday, March 24, 13
Food Chains• The energy flow from one trophic level to
the other is know as a food chain• A food chain is simple and direct• It involves one organism at each trophic
level– Primary Consumers – eat producers– Secondary Consumers – eat the
primary consumers– Tertiary Consumers – eat the
secondary consumers
Sunday, March 24, 13
Food Chains• The energy flow from one trophic level to
the other is know as a food chain• A food chain is simple and direct• It involves one organism at each trophic
level– Primary Consumers – eat producers– Secondary Consumers – eat the
primary consumers– Tertiary Consumers – eat the
secondary consumers– Decomposers – bacteria and fungi that
break down dead organisms and recycle the material back into the environment
Sunday, March 24, 13
Food Chains - a Reminder• A food chain shows which animals eat
other animals or plants.
Sunday, March 24, 13
Food Chains - a Reminder• A food chain shows which animals eat
other animals or plants.• Plants don’t eat things.
Sunday, March 24, 13
Food Chains - a Reminder• A food chain shows which animals eat
other animals or plants.• Plants don’t eat things.• A food chain starts with what gets
eaten and the arrows point towards what does the eating.
Sunday, March 24, 13
Food Chains - a Reminder• A food chain shows which animals eat
other animals or plants.• Plants don’t eat things.• A food chain starts with what gets
eaten and the arrows point towards what does the eating.
• Food chains only go in one direction.
Sunday, March 24, 13
Food Web
• Notice that the direction the arrow points, the arrow points in the direction of the energy transfer, NOT “what ate what”
Most organisms eat more the JUST one organism
When more organism are involved it is know as a FOOD WEB
Food webs are more complex and involve lots of organisms
Sunday, March 24, 13
Food WebsIn the wild, animals may eat more than one thing, so they belong to more than one food chain.
To get the food they need, small herbivores may eat lots of different plants, and carnivores may eat many different animals.
Sunday, March 24, 13
Breaking the Chain• Organisms living in a habitat depend on each other.• If one part of a food chain dies out or is greatly reduced, the
consumers have to find alternative food, move away, or starve.
Sunday, March 24, 13
Breaking the Chain• Organisms living in a habitat depend on each other.• If one part of a food chain dies out or is greatly reduced, the
consumers have to find alternative food, move away, or starve.• This then affects more consumers in the same way.
Sunday, March 24, 13
SymbiosisA close and permanent association between
organisms of different species
Sunday, March 24, 13
Symbiosis
– Mutualism – – a relationship in which both organisms benefit from
each otherExample: Birds eating pest off a rhino’s back
A close and permanent association between organisms of different species
Sunday, March 24, 13
Symbiosis
– Mutualism – – a relationship in which both organisms benefit from
each otherExample: Birds eating pest off a rhino’s back
A close and permanent association between organisms of different species
Sunday, March 24, 13
MutualismBoth organisms benefit from the relationship
Cleaner fish
Pollination
Lichens: algae + fungus
Sunday, March 24, 13
MutualismBoth organisms benefit from the relationship
Otters and Kelp
Cleaner fish
Pollination
Lichens: algae + fungus
Sunday, March 24, 13
MutualismBoth organisms benefit from the relationship
The otters help the kelp by eating the sea urchins which endanger it. The kelp provides and anchor for the otters while they sleep.
Otters and Kelp
Cleaner fish
Pollination
Lichens: algae + fungus
Sunday, March 24, 13
SymbiosisA close and permanent association between
organisms of different species
Sunday, March 24, 13
Symbiosis
– Commensalism – – a relationship in which one organism benefits and the
other is not affectedExample: Barnacles on a whale
A close and permanent association between organisms of different species
Sunday, March 24, 13
Symbiosis
– Commensalism – – a relationship in which one organism benefits and the
other is not affectedExample: Barnacles on a whale
A close and permanent association between organisms of different species
Sunday, March 24, 13
Barnacles on whalewww.cbu.edu
• A relationship in which one species benefits and the other is neither helped nor harmed
Commensalism
Barnacles and Whales
• Barnacles need a place to anchor. They must wait for food to come their way. Some barnacles hitch a ride on unsuspecting whales who deliver them to a food source. This does not effect the whale in any way.
Cattle with cattle egrets
Cattle stir up insects as they eat grass.Egrets hang around and eat insects.
Sunday, March 24, 13
SymbiosisA close and permanent association between
organisms of different species
Sunday, March 24, 13
Symbiosis
– Parasitism – – A relationship in which one organism benefits and the other
is harmed• Example: Ticks on a dog
A close and permanent association between organisms of different species
Sunday, March 24, 13
Symbiosis
– Parasitism – – A relationship in which one organism benefits and the other
is harmed• Example: Ticks on a dog
A close and permanent association between organisms of different species
Sunday, March 24, 13
Parasitism
Bedbugs are small, nocturnal parasites that come out of hiding at night to feed on unsuspecting humans. They feed exclusively on blood! Their bites often result in an allergic reaction.
Sunday, March 24, 13
Parasitism• One species benefits while the other is harmed
Bedbugs are small, nocturnal parasites that come out of hiding at night to feed on unsuspecting humans. They feed exclusively on blood! Their bites often result in an allergic reaction.
Sunday, March 24, 13
Parasitism• One species benefits while the other is harmed
Mistletoe is an aerial parasite that has no roots of its own and lives off the tree that it attaches itself to. Without that tree it would die. It slowly chokes out the life of the host tree.
Bedbugs are small, nocturnal parasites that come out of hiding at night to feed on unsuspecting humans. They feed exclusively on blood! Their bites often result in an allergic reaction.
Sunday, March 24, 13
Endangered or Extinct?
• The number of people in the world is growing at an alarming rate.
Sunday, March 24, 13
Endangered or Extinct?
• The number of people in the world is growing at an alarming rate.
• But this is not true for all animals.
Sunday, March 24, 13
Endangered or Extinct?
• The number of people in the world is growing at an alarming rate.
• But this is not true for all animals.• In some cases, there are only a few of one type
of animal left in the wild.
Sunday, March 24, 13
Endangered or Extinct?
• The number of people in the world is growing at an alarming rate.
• But this is not true for all animals.• In some cases, there are only a few of one type
of animal left in the wild.• These animals are endangered.
Sunday, March 24, 13
Endangered or Extinct?
• The number of people in the world is growing at an alarming rate.
• But this is not true for all animals.• In some cases, there are only a few of one type
of animal left in the wild.• These animals are endangered.• If they die out completely, they become
extinct.
Sunday, March 24, 13