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Niche concept

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Dr. Manju Bhaskar discusses the ecological niche concept. An ecological niche describes a species' functional role and position based on factors like resources, predators, habitat characteristics. G. Evelyn Hutchinson described the fundamental niche, being all conditions a species can survive in alone, and the realized niche, being conditions after interactions with other species. Niches allow populations to persist by reducing competition and filling different roles in food webs and ecosystems. Understanding niches provides insights into community composition and species responses to one another.

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Dr. Manju Bhaskar Assistant Professor Department of Zoology D. B. S. College (CSJM University) Kanpur 208006 Email: drmanjubhaskar19@gmail.com Niche Concept
• Ecological Niche: It is the functional role and position of a species in its environment that describes how the species distribution of resources and competitors or predators. • ‘The total of the adaptations of an organismic unit’ • Niches identify the 'role of an organism in its community’, or ‘the way a species makes its living’. Joseph Grinnell introduced the term. • Data on niches can be used to: Make comparisons of the composition and organization of communities. Examine shifts in the behavior or ecology of one species in response to another species. (In particular, niche shifts are commonly used to study interspecific competition, based on Gause’s Principle of Competitive Exclusion).
Ecological niche describe  The range of conditions necessary for persistence of the species  Its ecological role in the ecosystem. The ecological niche was defined by a place a species can take in nature, determined by its Abiotic requirements Food Preferences Microhabitat Characteristics (for example a foliage layer) Diurnal and Seasonal specialization Predation Avoidance This functional niche refers to a species position in trophic chains and food food webs, and the concept is thus especially relevant for ecosystem ecology.
• 1957, Zoologist G. Evelyn Hutchinson describe two forms of Niche • Fundamental Niche Fundamental niche is the entire set of conditions under which an animal (population, species) can survive and reproduce itself. It is focused on the conditions in which a species could exist with no ecological interactions. • Realized Niche Realized niche is the set of conditions actually used by given animal (pop, species), after interactions with other species (predation and especially competition) have been taken into account. It considered the population’s existence Fitness (for individual) or Population Growth Rate is zero outside the fundamental niche
Niche concept
Biotic Factors affecting a species' niche include Food Availability Predators. Abiotic Factors affecting ecological niche include  Temperature  Landscape characteristics  Soil Nutrients  Light Non-Living factors.
Realized Niche Fundamental Niche
Birds in New Zealand • Because New Zealand is an island separated from the rest of the world, it is utilized by by some unique plants and animals as a niche. • It includes few animals that are capable of flying or swimming, considering the distance distance of this place from the rest of the world. • Historically, in the absence of animals, the native animals like flying birds of the place place filled these niches. • The flying birds were the first known predators of this place. However, due to the absence of land animals, these birds eventually flew down on the land to fill up the niche, eventually becoming flightless. • Large birds like the Giant Moa grew up to 12 ft in height and about 500lb in weight, in the place of large mammals. • Birds like Kiwi live on land occupying niches of small mammals like mice and moles, feeding on seeds and insects. • The common birds present in New Zealand are South Island takahē, the Kakapo Parrot, and the Giant Moa.
Panda Bears • Panda bears have specialized niches where they have a limited diet, primarily feeding on bamboo. • Pandas do not move very far to reserve the very little energy they gather from such bamboos. • In order to preserve the available energy, they do not indulge in interspecific or intraspecific competition. • These are also no natural predators and they reproduce about once in two years to keep the population small in order to avoid the competition. • Their niche is specialized, which is why it is also highly sensitive to human activities. • They feed and live mostly around the bamboo trees which are increasingly destroyed by humans for farmland or mining. • These are now mostly limited to temperate or humid bamboo forests of South Western China.
Ecologists use the concept of the ecological niche to help understand how communities relate to environmental conditions, fitness, predator-prey interactions in communities. This becomes ever as climate change affects community ecology. Ecological niches allow species to exist in their environment. Under the right conditions, the species will thrive and play a unique role. Without the ecological niches, there would be less biodiversity, and the ecosystem would not be in balance. Interspecies competition: Ecologists refer to coexistence when ecological niches. Two competing species cannot exist in one ecological niche. This is due to limited resources. Competition affects the fitness of species, and can lead to evolutionary changes. An example of interspecies competition is an animal that forages for pollen or nectar from a specific plant species, competing with other such animals. In the case of some species of ants, the insects will compete for nests and
The degree and type of niche overlap can be used to assess interspecific competition. If niches overlap, and resources are limiting, then competition is currently occurring. Abutting niches are an (indirect) indication that competition may have lead to niche divergence in the past. Niche Overlap
Niche concept
Niche concept
Importance of Ecological Niches • Ecological niches are important for species, as they allow them to function without high competition for shared, limited resources. • Importance of ecological niches for an ecosystem when the species occupying it ceases to exist in it. • For example, the lack of bees has been seen to cause low fruit yields in greenhouses, due to a lack of pollination. Similarly, we can understand that if bee populations severely decrease on our planet, we might have problems growing sufficient food in the future. • The data gained from niche modeling has widespread applications, including in conservation projects and for planning ecological reserves.
• Some of the important theories and principles related to ecological niches include: • The Competitive Exclusion Principle • The competitive exclusion principle states that in an ecosystem, two species cannot continue to occupy the same niche forever. resources will lead to competition, which will force one or both species to adapt to either occupy a different niche or cease to exist. • This phenomenon is especially prominent in relation to invasive species, which may occupy the same niche as an indigenous species, and can drive the local species to extinction. • In R* Theory, multiple species cannot exist with the same resources unless they differentiate their niches. When resource density is at its lowest, those species populations most limited by the resource will be competitively excluded. • In P* Theory, consumers can exist at high density due to having shared enemies.
Referen ces • Ecological niche Jitka Polechová & David Storch DOI: 10.1016/B978-0-12- 409548-9.11113-3 • DOI: 10.13140/RG.2.2.33675.39208 • https://doi.org/10.3389/fmicb.2020.01942 • https://biologydictionary.net/niche/ • https://pediaa.com/difference-between-fundamental-niche-and-realized- niche/ • https://slideplayer.com/slide/14926288/ • https://slidetodoc.com/marine-ecosystems-and-biodiversity-the- connection-between-environment/
Niche concept

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Niche concept

  • 1. Dr. Manju Bhaskar Assistant Professor Department of Zoology D. B. S. College (CSJM University) Kanpur 208006 Email: drmanjubhaskar19@gmail.com Niche Concept
  • 2. • Ecological Niche: It is the functional role and position of a species in its environment that describes how the species distribution of resources and competitors or predators. • ‘The total of the adaptations of an organismic unit’ • Niches identify the 'role of an organism in its community’, or ‘the way a species makes its living’. Joseph Grinnell introduced the term. • Data on niches can be used to: Make comparisons of the composition and organization of communities. Examine shifts in the behavior or ecology of one species in response to another species. (In particular, niche shifts are commonly used to study interspecific competition, based on Gause’s Principle of Competitive Exclusion).
  • 3. Ecological niche describe  The range of conditions necessary for persistence of the species  Its ecological role in the ecosystem. The ecological niche was defined by a place a species can take in nature, determined by its Abiotic requirements Food Preferences Microhabitat Characteristics (for example a foliage layer) Diurnal and Seasonal specialization Predation Avoidance This functional niche refers to a species position in trophic chains and food food webs, and the concept is thus especially relevant for ecosystem ecology.
  • 4. • 1957, Zoologist G. Evelyn Hutchinson describe two forms of Niche • Fundamental Niche Fundamental niche is the entire set of conditions under which an animal (population, species) can survive and reproduce itself. It is focused on the conditions in which a species could exist with no ecological interactions. • Realized Niche Realized niche is the set of conditions actually used by given animal (pop, species), after interactions with other species (predation and especially competition) have been taken into account. It considered the population’s existence Fitness (for individual) or Population Growth Rate is zero outside the fundamental niche
  • 6. Biotic Factors affecting a species' niche include Food Availability Predators. Abiotic Factors affecting ecological niche include  Temperature  Landscape characteristics  Soil Nutrients  Light Non-Living factors.
  • 8. Birds in New Zealand • Because New Zealand is an island separated from the rest of the world, it is utilized by by some unique plants and animals as a niche. • It includes few animals that are capable of flying or swimming, considering the distance distance of this place from the rest of the world. • Historically, in the absence of animals, the native animals like flying birds of the place place filled these niches. • The flying birds were the first known predators of this place. However, due to the absence of land animals, these birds eventually flew down on the land to fill up the niche, eventually becoming flightless. • Large birds like the Giant Moa grew up to 12 ft in height and about 500lb in weight, in the place of large mammals. • Birds like Kiwi live on land occupying niches of small mammals like mice and moles, feeding on seeds and insects. • The common birds present in New Zealand are South Island takahē, the Kakapo Parrot, and the Giant Moa.
  • 9. Panda Bears • Panda bears have specialized niches where they have a limited diet, primarily feeding on bamboo. • Pandas do not move very far to reserve the very little energy they gather from such bamboos. • In order to preserve the available energy, they do not indulge in interspecific or intraspecific competition. • These are also no natural predators and they reproduce about once in two years to keep the population small in order to avoid the competition. • Their niche is specialized, which is why it is also highly sensitive to human activities. • They feed and live mostly around the bamboo trees which are increasingly destroyed by humans for farmland or mining. • These are now mostly limited to temperate or humid bamboo forests of South Western China.
  • 10. Ecologists use the concept of the ecological niche to help understand how communities relate to environmental conditions, fitness, predator-prey interactions in communities. This becomes ever as climate change affects community ecology. Ecological niches allow species to exist in their environment. Under the right conditions, the species will thrive and play a unique role. Without the ecological niches, there would be less biodiversity, and the ecosystem would not be in balance. Interspecies competition: Ecologists refer to coexistence when ecological niches. Two competing species cannot exist in one ecological niche. This is due to limited resources. Competition affects the fitness of species, and can lead to evolutionary changes. An example of interspecies competition is an animal that forages for pollen or nectar from a specific plant species, competing with other such animals. In the case of some species of ants, the insects will compete for nests and
  • 11. The degree and type of niche overlap can be used to assess interspecific competition. If niches overlap, and resources are limiting, then competition is currently occurring. Abutting niches are an (indirect) indication that competition may have lead to niche divergence in the past. Niche Overlap
  • 14. Importance of Ecological Niches • Ecological niches are important for species, as they allow them to function without high competition for shared, limited resources. • Importance of ecological niches for an ecosystem when the species occupying it ceases to exist in it. • For example, the lack of bees has been seen to cause low fruit yields in greenhouses, due to a lack of pollination. Similarly, we can understand that if bee populations severely decrease on our planet, we might have problems growing sufficient food in the future. • The data gained from niche modeling has widespread applications, including in conservation projects and for planning ecological reserves.
  • 15. • Some of the important theories and principles related to ecological niches include: • The Competitive Exclusion Principle • The competitive exclusion principle states that in an ecosystem, two species cannot continue to occupy the same niche forever. resources will lead to competition, which will force one or both species to adapt to either occupy a different niche or cease to exist. • This phenomenon is especially prominent in relation to invasive species, which may occupy the same niche as an indigenous species, and can drive the local species to extinction. • In R* Theory, multiple species cannot exist with the same resources unless they differentiate their niches. When resource density is at its lowest, those species populations most limited by the resource will be competitively excluded. • In P* Theory, consumers can exist at high density due to having shared enemies.
  • 16. Referen ces • Ecological niche Jitka Polechová & David Storch DOI: 10.1016/B978-0-12- 409548-9.11113-3 • DOI: 10.13140/RG.2.2.33675.39208 • https://doi.org/10.3389/fmicb.2020.01942 • https://biologydictionary.net/niche/ • https://pediaa.com/difference-between-fundamental-niche-and-realized- niche/ • https://slideplayer.com/slide/14926288/ • https://slidetodoc.com/marine-ecosystems-and-biodiversity-the- connection-between-environment/