Unit 1 Lesson 1 : Introduction to Ecosystems

Interaction in ecosystems can include ...

-Predator-prey relationships -Symbiotic interaction -Mutualism -Commensalism -Parasitism -Competition -Between different species -Within a single species

What is symbiosis?

-a close, long-term interaction between two species in an ecosystem -greek "sym" together + "bio" living = symbiosis "living together"

Parasitism

-is a relationship where and organism lives on or inside of another. -other organism called the host -one species benefits, other is harmed -do harm their hosts, rarely cause death -fleas/ticks on mammals -intestinal tapeworms -mosquitos biting warm blooded animals -malarial infections in human

Mutualism

-is a symbiotic relationship between two species where both receive a benefit that results in an increased chance of survival and reproduction -relationships are long term, and both species have evolved traits over many generations that aid the relationship -ants and acacia trees -lichens -corals -clownfish and sea anemones

Predator-Prey Relationships

-predators hunt and kill prey -biotic interaction -for predators, the prey is a food source -as the availability of the prey fluctuates, the number of predators does, as well

Commensalism

-refers to species interactions in which one species receives a benefit, and the other species is unaffected by the interactions -one species benefits, other is neither helped nor harmed -latin "com" same + "mensal" table = commensalism "at the same table" -long term and the species involved have evolved these relationships many generations -black backed jackals scavenging kills -owls nesting in the hallows of tress -cattle and egrets -hermit crabs and discarded snail shells

Competition

-results when individuals from different species OR within the same species struggle to obtain the same limiting resource

Competition within a single species

-sometimes called infraspecific competition, occurs when individuals must fight for the same resource that all members of a species need to survive -may be biotic, such as access to mates, or abiotic, such as space for a plant's root systems to spread out -"fittest" individual will gain access to the resource, and will survive to reproduce. makes a species stringer and better adapted to its environment overall.

Competition between species

-sometimes called interspecific competition, occurs when the species must fight over a shared, limiting resource -might be biotic, such as access to a food source, or biotic, such as a competition for available sunlight on a forest floor -is harmful for both and over time, species will seek to limit their use of a shared resource over which they must compete

What is an ecosystem?

An ecosystem in a community of living organisms in conjunction with the non-living components of their environment, interacting as a system. Ecosystems are the result of BIOTIC and ABIOTIC interactions.

Biotic

Living - Producers (plants, photosynthetic algae, phytoplankton, etc) -Herbivores -Carnivores -Omnivores -Detritivores -Soil

Abiotic

Non-living -Sunlight -Temperature -Precipitation -Moisture/water -pH -Soil

limiting resource

any resource, biotic or abiotic, that constrains a population's size or could potentially stop a population from growing.

Resource Partitioning

occurs when species use limiting resources in different ways, places, or at different times, in an attempt to reduce competition