Introduction to Ecosystems and Hierarchy Lecture by: Stephanie Soomar

Lesson Agenda 1.What is Ecology? 2.Levels of Hierarchy (Organization) 3.Abiotic versus Biotic 4.Habitat versus Niche

is the study of the interaction of organisms with their physical and biological environments and how these interactions determine the distribution and abundance of the organisms. What is Ecology?

Largest to Smallest Biosphere Ecosystem Community Population Individual Largest to Smallest Biosphere Ecosystem Community Population Individual Ecological Hierarchy

Hierarchy of Organization Biosphere—the broadest, most inclusive, level of organization. Consists of the Earth and its atmosphere. It supports all life. All organisms are found within the biosphere. The biosphere consists on 6 major biomes. Biosphere—the broadest, most inclusive, level of organization. Consists of the Earth and its atmosphere. It supports all life. All organisms are found within the biosphere. The biosphere consists on 6 major biomes.

6 Biomes 6 major biomes: 1.Freshwater 2.Marine (Aquatic) 3.Desert 4.Forest 5.Grassland 6.Tundra 6 major biomes: 1.Freshwater 2.Marine (Aquatic) 3.Desert 4.Forest 5.Grassland 6.Tundra Show video:

Ecosystem An ecosystem includes all the living organisms and the physical and chemical factors (nonliving) which influence them. Example: rocky shore An ecosystem includes all the living organisms and the physical and chemical factors (nonliving) which influence them. Example: rocky shore Show video:

Abiotic versus Biotic Biotic (living): fish algae insects bacteria frogs turtles Abiotic (non-living): air - soil water - salinity pH oxygen carbon dioxide temperature sunlight pollution

A Marine Ecosystem Biotic = phytoplankton, zooplankton, fishes, corals, crustaceans Abiotic = chemicals, sunlight, water, currents, pH, salinity, sediments

A Terrestrial Ecosystem Biotic = trees, grass, animals, insects, lichen, etc. Abiotic = sunlight, water, soil, rocks, etc.

Abiotic versus Biotic Complete the Abiotic versus Biotic worksheet

Community Includes all the different species living in a habitat at the same time. Example: the mollusk community on a rocky shore, which would include all the different species of mollusks living in this habitat. Includes all the different species living in a habitat at the same time. Example: the mollusk community on a rocky shore, which would include all the different species of mollusks living in this habitat.

Population Consists of organisms of the same species, usually defined as living in the same area. Example: a population of ghost crabs (Ocypode saratan) living on a sandy shore. Consists of organisms of the same species, usually defined as living in the same area. Example: a population of ghost crabs (Ocypode saratan) living on a sandy shore.

Individual & Species The simplest level of organization in ecology is that of the individual. Individual: 1 organism Species: is defined as a group of similar organisms that can interbreed and produce fertile offspring. Example: skipjack tuna (Katsuwonus pelamis) and the red mangrove trees (Rhizophora mangle) The simplest level of organization in ecology is that of the individual. Individual: 1 organism Species: is defined as a group of similar organisms that can interbreed and produce fertile offspring. Example: skipjack tuna (Katsuwonus pelamis) and the red mangrove trees (Rhizophora mangle) Binomial Nomenclature: Each species is given a name consisting of 2 parts. 1.First name: genus or generic name 2.Second name: species or specific name Why are species given 2 part names? See video on “Interactions Among Organisms” under Marine Ecosystem videos on flashdrive

Habitat versus Niche A habitat is the place where organisms live. – For example: the area surrounding a hydrothermal vent provides a habitat for species of tube worms and other specialized organisms A niche is the role of an organism within an ecosystem, taking into account its relationships with other organisms. – In a marine ecosystem, the niche of a great white shark is the top predator. Organisms which occupy similar niches will tend to compete with each other for resources, such as food and space to live in their habitat. A habitat is the place where organisms live. – For example: the area surrounding a hydrothermal vent provides a habitat for species of tube worms and other specialized organisms A niche is the role of an organism within an ecosystem, taking into account its relationships with other organisms. – In a marine ecosystem, the niche of a great white shark is the top predator. Organisms which occupy similar niches will tend to compete with each other for resources, such as food and space to live in their habitat.

Hydrothermal vents and tubeworms

The niche of the Great White Shark is top predator.

Habitat The habitat is the place where an organism lives out its life. – It is where the organism finds food, shelter and mates. – Several species can live in the same habitat but will use the resources in different ways.

Niche A niche is all strategies and adaptations a species uses in its environment. – This is how organisms obtain food, mates and protection from predators. – No two species can occupy the same niche long (one species will go extinct). – “By analogy, it may be said that the habitat is the organism's ‘address’, and the niche is its ‘profession’, biologically speaking.”

Habitat vs. Niche limiting factor A niche is determined by the tolerance limitations of an organism, or a limiting factor. Limiting factor: Any biotic or abiotic factor that restricts the existence of organisms in a specific environment.

limiting factors Examples of limiting factors- Habitat vs. Niche 1.Amount of water 2.Amount of food 3.Temperature

Which level is it? Identify the level of ecological organization represented by each picture. A herd of buffalo.

Which level is it? All of the living and non-living items in a pond

Which level is it? All of the animal populations living on the African savannah. See video: