NICHES in the Ecosystem
The Biological Niche
Objectives
Niche (figuratively) – to have found a “position” in society that is uniquely their own.
Oxford Dictionaries
Niche (figuratively) – to have found a position or occupation in society that is uniquely their own.
To make good decisions.
To make good predictions.
To ensure species survival.
To maintain ecological balance.
Introduction of non-indigenous species to non-native habitats by humans often results in biological pollution by the exotic or invasive species.
Cane toads were introduced to Australia in 1935 as a biological control method against the Greyback cane beetle that was destroying sugar cane crops.
Its range has expanded southward, through Australia with no outlook of control.
To make good predictions.
To ensure species survival.
To maintain ecological balance.
Objectives
- To understand what a niche is in the field of ecology
- To understand the differences between a fundamental niche and a realized niche
- Why are niches important to understand
- How this knowledge is used
- What is a NICHE?
Niche (figuratively) – to have found a “position” in society that is uniquely their own.
Oxford Dictionaries
- Niche
- Organisms carve out their own unique niches that they specialize in, and it is extremely unusual to find two organisms with the same exact niche. Too much competition for resources.
- https://study.com/academy/lesson/ecological-niche-definition-lesson-quiz.html
- Biotic factors – living things
- Abiotic factors – non-living
- What is a NICHE?
Niche (figuratively) – to have found a position or occupation in society that is uniquely their own.
- Hutchinson’s Definition of Niche
- Hypervolume - A region defined by more than three dimensions.
- What Does a Hypervolume Look Like?
- Fig. a three-dimensional niche.
- Specific Leaf Area (SLA) vs
- Height of habitat
- Seed Mass
- The Lichen – An Example of a Biological Niche
- A lichen is a composite organism that arises from algae or cyanobacteria (or both) living among filaments of a fungus in a symbiotic relationship.[1][2][3] The combined life form has properties that are very different from the properties of its component organisms. Lichens come in many colors, sizes, and forms.
- The Lichen – An Example of a Biological Niche
- The properties are sometimes plant-like, but lichens are not plants. Lichens may have tiny, leafless branches (fruticose), flat leaf-like structures (foliose), flakes that lie on the surface like peeling paint (crustose),[4] or other growth forms.[5] crustose
- The Lichen – An Example of a Biological Niche
- A macrolichen is a lichen that is either bush-like or leafy; all other lichens are termed microlichens.[1] Here, "macro" and "micro" do not refer to size, but to the growth form.[1] Common names for lichens may contain the word "moss" (e.g., "Reindeer moss", "Iceland moss"), and lichens may superficially look like and grow with mosses, but lichens are not related to mosses or any plant.[3]:3
- The Lichen – An Example of a Biological Niche
- Lichens do not have roots that absorb water and nutrients as plants do[6]:2 but like plants they produce their own food by photosynthesis using sunlight energy, from carbon dioxide, water and minerals in their environment.[7] When they grow on plants, they do not live as parasites and only use the plants as a substrate.
- The FUNDAMENTAL Niche
- The Fundamental Niche
- The fundamental niche is usually NOT observed in nature. In a ‘perfect’ world (perfect for that particular species) this is what the niche for that species would potentially be.
- It sort of like FALSE ADVERTISING.
- The FUNDAMENTAL Niche
- The REALIZED Niche
- The REALIZED Niche
- Fundamental vs. Realized
- Overlapping Niches
- Gause's Law of Competitive Exclusion
- Organisms Must Compromise
- Warbler Bird
- Fundamental
- Why Should We Learn About Niches?
To make good decisions.
To make good predictions.
To ensure species survival.
To maintain ecological balance.
- What Can Go Wrong?
Introduction of non-indigenous species to non-native habitats by humans often results in biological pollution by the exotic or invasive species.
- What Can Go Wrong?
Cane toads were introduced to Australia in 1935 as a biological control method against the Greyback cane beetle that was destroying sugar cane crops.
- Consequences of Misunderstanding Niches
- The Greyback beetle eats the top of the sugar cane where the toads cannot reach them.
- The Greyback beetle is active during the day, but Cane toads feed at night.
- The two species are not in the same place at the same time of year.
- The toads need wet conditions to survive, so they moved from the sugar cane fields to moister areas.
Its range has expanded southward, through Australia with no outlook of control.
- How do we find the niche?
- For every known location of a species
- Compare the conditions of where they are found to the conditions of where they are not found.
- Factors to consider
- Temperature
- Rainfall
- Soil
- Nitrogen availability
- Niche define the TOLERANCE of the species.
- How do we find the niche?
- Look at the distribution of 2 species over a gradient of moisture availability.
- Species 1 - Soft Tree Fern (Dicksonia antarctica)
- Wooly and soft to the touch
- Wide trunk
- 3-4 meters high
- Hang on to dead fronds
- Species 2 - Rough Tree Fern(Cyathea australis)
- Rough to the touch
- Slender trunk
- 8-9 meters high
- How do we find the niche?
- Abundance vs Moisture
- Understanding the Niche…
To make good predictions.
To ensure species survival.
To maintain ecological balance.
