Exploring the Redwoods to understand Habitat/ Niche Resource Partitioning Generalist vs. Specialist

The Redwood Forests Video Overview

Habitat vs Niche Habitat is the physical location that an organism occupies Niche- how an organism makes its living. How it obtains food, its relationships with other organisms, services it provides the ecosystem, all behaviors needed for it to survive

Banana Slug Habitat Sides of Redwoods Redwood Forest Floor Niche Eats scat, leaves, fungus Solitary Uses sides of tree to keep cool Camouflaged

Competitive Exclusion Two species that compete for the exact same resources cannot stably coexist One species will always have a slight advantage over the other – One species evolves OR – One species becomes extinct

“It’s a Slug Fest” Spotted Leopard Slugs and Banana Slugs are thought to have occupied the same habitats. The Spotted Leopard Slug left the Redwood Forests are known to prefer gardens. In fact, most species of leopard slugs are now associated with “human habitats”.

A Tale of three squirrels Northern Flying Squirrel Western Gray Squirrel Chickaree Squirrel

Competition Two types of competition: – Intraspecific- competition among members of the same species – Interspecific– competition among members of different species

Changes The Law of Competitive Exclusion most likely led to the three species of squirrels in the Redwood Forests. All three new species then had to deal with Interspecific Competition Otherwise they would be fierce competitors

A Tale of three squirrels Northern Flying Squirrel NOCTURNAL Western Gray Squirrel DIURNAl Chickaree Squirrel DIURNAL

A Tale of three squirrels Northern Flying Squirrel Eats Fungi Western Gray Squirrel Eats Redwood Pine Cone Seeds Chickaree Squirrel Douglas Fir and White Pine Cone Seeds

Resource Partitioning Northern Flying Squirrel Western Gray Squirrel Chickaree Squirrel Resource Partitioning- High levels of specialization That allow several species To utilize different parts of the Same resource and coexist Within a single habitat.

There is a danger to Resource Partitioning Generalist- these are species that do not have specific habitat or food requirements. You see these organisms colonize large areas of land…event he globe Example: Humans Specialist- require special habitats or specialized food resources. Examples: Our squirrel friends Endangered and threatened Species

Side track…. They are just to cool, you gotta check this out! Is it a Bird? Is it a plane? No, it's a flying squirrel! Is it a Bird? Is it a plane? No, it's a flying squirrel!

Producers Redwood Tree Moss Fern Shooting Star Violet

First Order Consumers (Herbivores)

Second and Third order Consumers

Decomposers

Scavengers

Life on the Prairie As you watch note the following: – Habitat= Prairie – Niches – Specific Feeding Relationships – Law of Competitive Exclusion Interspecific and Intraspecific – Resource Partitioning

An Evolutionary Side Note Gigantism and Dwarfism Foster’s Rule-also known as the island rule) is a principle in evolutionary biology stating that members of a species get smaller or bigger depending on the resources available in the environment. Hising Cockroaches Key Deer Komodo Dragon