Ecological Niches

Habitat

-physical local where something lives, can change because of the animals that live there

Niche

A specific role a species has in an ecosystem

-Determined by abiotic and biotic factors

-Only when a species is in their appropriate niche that they can find food, grow, and reproduce

Fundamental Niche

-Every place a niche could exist in given their adaptations

-A range of living conditions a species can tolerate

Realized Niche

-the actual places a species live

-Competition for resources makes living conditions for niches more specific s

Competition

-When two or more species occupy the same niche and require similar resources

-There are strong and weak competitors

Competitive exclusions

-Two species may share their fundamental niche

-One species will outcompete the other species

-Human impacts on the environment influences competition between species 

Invasive species

-Species non-native to an ecosystem that has no natural predator

-May outcompete endemic species for the same niche 

-Can bring diseases to non-resistant organisms 

Abiotic Factors

-Temperature: Polar bears

-Light: Ferns don’t require as much sunlight and would die if exposed to excessive sunlight 

-Humidity: fungus, mold thrive in warm and wet conditions

Biotic Factors 

-Food source: Pandas consume bamboo, and they cannot survive outside of a bamboo forest 

-Shelter: desert rats bury underground

-Symbiosis: zooxanthelle are microorganisms that live on coral reefs, mutually beneficial relationship

Tolerance Animals

Animals have a certain level of tolerance towards abiotic factors:

-Temp

-Water availability

Plant tolerance

-Soil pH: not within pH optimal levels affects plants’ abilities to take in ions, cannot take in nutrients 

-Sunlight: Some plants don’t require as much sunlight to photosynthesize

-Rainfall

-Temperature: influences the productivity of RuBisCo

-Freezing temperatures can cause cells to freeze up and burst 

-Seasonal changes 

Marram grass

-Mostly seen in dunes near the coast

-adapted to hot and dry, windy, salty, and loose sand conditions 

How does Marram grass adapt to its condition? 

-Hot and Dry: High SA and waxy coating to maximize water retention, is a xerophyte (does not need that much water) 

-Curves increase SA, create microclimates that prevent water loss, trichomes inc. SA

-Windy: Have curved, flexible leaves

-Salty: Marram grass salt-resistant

Mangrove trees

-Secretion of excess from leaves pushes salt back out

-Sacrificial leaves: growing enough leaves to make up for those that fall

-Stilt roots offer support in mud

-Pneumatophores: allow gas exchange, aerial roots, and absorb oxygen from the air

-large buoyant seeds

-accumulation of minerals and carbon compounds in roots to allow water absorption from salty water, root ultra-filtrate water

Animal Tolerance Limits towards abiotic factors

-Temperatures: can move to adapt, make heat, hibernate

-Water: animals move to follow water

-Breeding sites: find a mate and raise children

-food

-territory: hunting, finding water

Mirco-organisms 

-Don’t all require oxygen to live 

-Obligate: must have 

-Facultative: optional 

Saprotrophic 

-feed on decaying and dead matter, digest food externally before nutrients are absorbed

Parasitic

-Obtain nutrients from living organisms

Holozic

feed by ingesting solid organic matter which is then digested and absorbed

Mixotrophy

-Both heterotrophy and autotrophy

-Protistas 

-Obligate mixotrophy must do both 

-Facultative can do either 

Insects

-Insects are mostly herbivores

-Have jaw-like mouthparts to bite and chew

-Tubular mouthparts help pierce through leaves and sucking saps 

Physical defenses of plants

-Thorne

-Spine

-prickle 

-trichome