Ecological Niches and Niche Differentiation

Vocabulary terms and definitions based on the lecture discussion of fundamental and realized niches, mechanisms of resolving niche conflict, finch and penguin examples, and human adaptations in Tierra del Fuego.

Niche

The specific role or relationship that a species fills within an ecosystem, defined at the species level by its interactions with other elements.

Fundamental Niche

The potential role that a species could play in an ecosystem given its biological capabilities, assuming an ideal environment without competition.

Realized Niche

The actual role a species plays in an environment when interacting and negotiating for resources alongside competing species.

Competitive Exclusion

An outcome of niche conflict where one species completely outcompeted or drives out another species, leading to its local removal or extinction.

Character Displacement

An outcome of niche overlap where competing species adapt physical or behavioral traits over evolutionary time to eliminate direct competition.

Reduced Carrying Capacity

An outcome of niche conflict where competing species coexist in the same space by reducing their population size or reproducing less.

Chinstrap Penguin

An Antarctic penguin species whose foraging niche involves remaining close to the colony shore and making shallow water dives for krill.

Adélie Penguin

An Antarctic penguin species characterized by a white eye ring that swims long distances from the colony to forage for krill and squid.

Gentoo Penguin

An Antarctic penguin species that travels an intermediate distance from the shore and dives much deeper than neighboring species to catch krill and fish.

Bill Depth

The vertical measurement of a finch's beak that determines how hard of a seed the bird is physically capable of crushing.

Yámana

An indigenous coastal population of Tierra del Fuego who adapted to cold marine conditions by swimming, hunting marine life, and gathering around large fires without wearing clothing.

Selk'nam

An indigenous population of Tierra del Fuego who inhabited the flat plains, wore Wanaco pelts, and relied heavily on Wanacos for food and tools.

Tierra del Fuego

A region at the southern tip of South America named 'Land of Fire' by European explorers who observed the shoreline fires built by the Yámana people.