Life tables summarize the mortality rates of a population over time. They track the number of individuals surviving (lx) and dying (dx) in each age interval. This data can be used to calculate other metrics like the proportion surviving (Sx), expected remaining life (ex), and mortality rate (qx). Survivorship curves graphically depict the decline in survivors over the lifespan based on life table data. There are three main types of survivorship curves: highly convex, intermediate, and highly concave. These curves reflect different mortality patterns across age classes.
Answer for 1 is curve BAnswer for 2 is curve AAnswer for 3 is cu.pdfankurelectronicsg3
Answer for 1 is curve B
Answer for 2 is curve A
Answer for 3 is curve C
This is a survivorship curve graph showing the number or proportion of individuals surviving to
each age for a given species or group. The number or proportion of organisms surviving to any
age is plotted on the y-axis, with a logarithmic scale, while their age, often as a proportion of
maximum life span, is plotted on the x-axis.
There are three types of survivorship curves:
Type I curves has high age-specific survival probability in early and middle life, followed by a
rapid decline in survival in later life. They are typical of species like humans and large mammals
like elephant.
Type II curves are an intermediates with constant mortality rate/survival probability is
experienced regardless of age. Some birds and some lizards follow this pattern. Even seagulls.
Type III curves have lowest age-specific survival in early in life, with relatively low rates of
death for those surviving this bottleneck. This type of curve is characteristic of species that
produce a large number of offspring . This includes redwood trees.
Solution
Answer for 1 is curve B
Answer for 2 is curve A
Answer for 3 is curve C
This is a survivorship curve graph showing the number or proportion of individuals surviving to
each age for a given species or group. The number or proportion of organisms surviving to any
age is plotted on the y-axis, with a logarithmic scale, while their age, often as a proportion of
maximum life span, is plotted on the x-axis.
There are three types of survivorship curves:
Type I curves has high age-specific survival probability in early and middle life, followed by a
rapid decline in survival in later life. They are typical of species like humans and large mammals
like elephant.
Type II curves are an intermediates with constant mortality rate/survival probability is
experienced regardless of age. Some birds and some lizards follow this pattern. Even seagulls.
Type III curves have lowest age-specific survival in early in life, with relatively low rates of
death for those surviving this bottleneck. This type of curve is characteristic of species that
produce a large number of offspring . This includes redwood trees..
Ppt is made vailable for public for scientifc use.
Population ecology concept and its characteristics explained by using practical examples in a simple language. data is significant for competitive examinations
This document provides an overview of key concepts in population ecology. It discusses population characteristics like density, natality, mortality, dispersal, growth curves, fluctuation, distribution, age pyramids, and equilibrium. It describes population density, natality rates, types of mortality, dispersal through emigration, immigration and migration. Growth curves can follow a J-curve or S-curve pattern. Populations can fluctuate cyclically. Distribution can be random, uniform, or clumped. Age pyramids reflect the age structure of a population.
Population ecology examines how populations change over time based on birth, death, immigration, and emigration rates. Key concepts include:
- Populations have a density that can be influenced by density-dependent and density-independent factors.
- Natality is the birth rate and mortality is the death rate. These determine a population's growth rate.
- Populations can exhibit exponential or logistic growth patterns depending on available resources/carrying capacity.
- Reproductive strategies like r/K selection influence life history traits and population dynamics.
- Competition between species occupying the same niche frequently leads to competitive exclusion of one species.
A population is a group of individuals of the same species that live together in a region. Population ecology studies populations and their interactions with the environment. Populations have characteristics like density, birth rate, death rate, and distribution that can be measured and compared. [END SUMMARY]
This document discusses key concepts in population ecology, including estimating patterns of survival, survivorship curves, age distribution, rates of population change, and dispersal. It provides examples of how these concepts can be studied, such as using life tables to construct survivorship curves and estimate net reproductive rate. Dispersal is explored in the contexts of climate change, changing food supply, and dispersal within river systems.
Life tables summarize the mortality rates of a population over time. They track the number of individuals surviving (lx) and dying (dx) in each age interval. This data can be used to calculate other metrics like the proportion surviving (Sx), expected remaining life (ex), and mortality rate (qx). Survivorship curves graphically depict the decline in survivors over the lifespan based on life table data. There are three main types of survivorship curves: highly convex, intermediate, and highly concave. These curves reflect different mortality patterns across age classes.
Answer for 1 is curve BAnswer for 2 is curve AAnswer for 3 is cu.pdfankurelectronicsg3
Answer for 1 is curve B
Answer for 2 is curve A
Answer for 3 is curve C
This is a survivorship curve graph showing the number or proportion of individuals surviving to
each age for a given species or group. The number or proportion of organisms surviving to any
age is plotted on the y-axis, with a logarithmic scale, while their age, often as a proportion of
maximum life span, is plotted on the x-axis.
There are three types of survivorship curves:
Type I curves has high age-specific survival probability in early and middle life, followed by a
rapid decline in survival in later life. They are typical of species like humans and large mammals
like elephant.
Type II curves are an intermediates with constant mortality rate/survival probability is
experienced regardless of age. Some birds and some lizards follow this pattern. Even seagulls.
Type III curves have lowest age-specific survival in early in life, with relatively low rates of
death for those surviving this bottleneck. This type of curve is characteristic of species that
produce a large number of offspring . This includes redwood trees.
Solution
Answer for 1 is curve B
Answer for 2 is curve A
Answer for 3 is curve C
This is a survivorship curve graph showing the number or proportion of individuals surviving to
each age for a given species or group. The number or proportion of organisms surviving to any
age is plotted on the y-axis, with a logarithmic scale, while their age, often as a proportion of
maximum life span, is plotted on the x-axis.
There are three types of survivorship curves:
Type I curves has high age-specific survival probability in early and middle life, followed by a
rapid decline in survival in later life. They are typical of species like humans and large mammals
like elephant.
Type II curves are an intermediates with constant mortality rate/survival probability is
experienced regardless of age. Some birds and some lizards follow this pattern. Even seagulls.
Type III curves have lowest age-specific survival in early in life, with relatively low rates of
death for those surviving this bottleneck. This type of curve is characteristic of species that
produce a large number of offspring . This includes redwood trees..
Ppt is made vailable for public for scientifc use.
Population ecology concept and its characteristics explained by using practical examples in a simple language. data is significant for competitive examinations
This document provides an overview of key concepts in population ecology. It discusses population characteristics like density, natality, mortality, dispersal, growth curves, fluctuation, distribution, age pyramids, and equilibrium. It describes population density, natality rates, types of mortality, dispersal through emigration, immigration and migration. Growth curves can follow a J-curve or S-curve pattern. Populations can fluctuate cyclically. Distribution can be random, uniform, or clumped. Age pyramids reflect the age structure of a population.
Population ecology examines how populations change over time based on birth, death, immigration, and emigration rates. Key concepts include:
- Populations have a density that can be influenced by density-dependent and density-independent factors.
- Natality is the birth rate and mortality is the death rate. These determine a population's growth rate.
- Populations can exhibit exponential or logistic growth patterns depending on available resources/carrying capacity.
- Reproductive strategies like r/K selection influence life history traits and population dynamics.
- Competition between species occupying the same niche frequently leads to competitive exclusion of one species.
A population is a group of individuals of the same species that live together in a region. Population ecology studies populations and their interactions with the environment. Populations have characteristics like density, birth rate, death rate, and distribution that can be measured and compared. [END SUMMARY]
This document discusses key concepts in population ecology, including estimating patterns of survival, survivorship curves, age distribution, rates of population change, and dispersal. It provides examples of how these concepts can be studied, such as using life tables to construct survivorship curves and estimate net reproductive rate. Dispersal is explored in the contexts of climate change, changing food supply, and dispersal within river systems.
Population ecology is a field of scientific research that examines the dynamics of populations of living organisms within a given environment. It involves the study of various aspects of populations, including their growth, distribution, density, age structure, and the factors that affect these attributes. Key components of population ecology include:
Population Dynamics: Population ecologists study how the size of a population changes over time. This involves examining birth rates (natality), death rates (mortality), immigration, and emigration.
Population Distribution: Understanding how individuals in a population are spatially distributed is essential. Populations can be clumped, evenly dispersed, or randomly distributed in a habitat.
Population Density: This refers to the number of individuals of a species per unit area or volume of habitat. Population density can have significant ecological and environmental implications.
Age Structure: The age distribution within a population can provide insights into its growth potential and reproductive capacity. It can help in predicting future population trends.
Population Growth Models: Population ecologists use mathematical models to describe and predict population growth, such as exponential and logistic growth models.
Limiting Factors: Population growth is limited by various factors, including availability of resources, predation, competition, disease, and environmental conditions. Population ecologists study how these factors influence population dynamics.
Carrying Capacity: The carrying capacity of an environment is the maximum population size that can be sustained by available resources without causing environmental degradation or resource depletion.
Interactions: Populations do not exist in isolation. Interactions with other species, such as predation, competition, and mutualism, are essential considerations in population ecology.
Conservation and Management: Population ecology plays a critical role in the conservation and management of endangered species and ecosystems. It helps in making informed decisions to protect and sustainably manage populations.
Research Methods: Population ecologists employ various field and laboratory techniques, including population censuses, mark and recapture studies, and modeling, to gather data and understand population dynamics.
Application of life tables in insect pest managementchidanand4098
Life tables are used in insect pest management to track mortality rates across different life stages of a population. An ecologist constructs a life table by observing many individuals over time and recording offspring production, deaths, and mortality factors. This data is then summarized to calculate average mortality rates within each developmental stage. Life tables are useful for determining the key factors influencing population size changes and the stages when a population is most vulnerable. This information can be applied to pest control by focusing control methods during vulnerable stages.
I MSc II Semester - Characteristics of a population.pptaigil2
This document outlines the key characteristics of populations including: population density, natality (birth rate), mortality (death rate), population growth curves, age distribution through age pyramids, and population fluctuations. It defines these terms and describes how they are measured or expressed. For example, population density can be crude or ecological density and is calculated as the number of individuals divided by the area. Population growth follows either a sigmoid or J-shaped curve over time.
This document discusses various attributes of populations and population growth. It describes birth rate, death rate, population density, age distribution, and sex ratio as key attributes of populations. Population growth curves can take a sigmoid or S-shaped form, with phases of lag, acceleration, and plateau, or a J-shaped form with rapid exponential growth until environmental resistance increases. Population change over time is determined by the balance of births, deaths, immigration and emigration. The carrying capacity of the environment limits population growth.
This document discusses various population characteristics and dynamics. It defines a population as a group of the same species living together in a region. Population ecology studies populations and their interactions with the environment. Key population characteristics include density, natality, mortality, growth forms, and distribution. Density refers to the number of individuals per unit area or volume. Natality is birth rate and mortality is death rate. Other concepts covered include survivorship curves, dispersion patterns, age structure through age pyramids, and population dispersal through emigration, immigration, and migration.
1. The document discusses various levels of biological organization from the ecosystem level down to the molecular level, providing examples like the eucalyptus forest ecosystem and the flying fox population.
2. It then focuses on population ecology, defining key population features like size, density, dispersion, growth rates, and factors that influence population growth like immigration, emigration, birth rates and death rates.
3. Models of population growth are discussed, including exponential and logistic growth curves, and the concept of carrying capacity is introduced as the maximum population size supported by available resources.
Population ecology examines populations as units of study. A population has characteristics like density, size, age structure, and dispersion. The four basic population parameters that affect density are natality, mortality, immigration, and emigration. Techniques to estimate population density include using quadrats, capture-recapture methods, and calculating relative density with tools like traps or roadside counts. Life tables can describe mortality schedules by tracking age-specific cohort survival. Population growth rates depend on birth and death rates, and can be modeled exponentially or logistically depending on environmental constraints.
Population ecology is the study of populations in relation to their environment. It includes influences on population density, distribution, age structure, and variations in population size. Key attributes of populations include birth rate, death rate, population density, sex ratio, and age distribution. Population growth occurs when birth rate exceeds death rate, though populations are limited by environmental carrying capacity. Populations interact through neutral, positive (e.g. mutualism), and negative (e.g. competition, predation) interactions that influence community structure.
Population ecology is the study of populations in relation to their environment. It examines factors like population size, density, dispersion patterns, demographics, survivorship curves, and population growth. Population size is influenced by birth rate, death rate, immigration, and emigration. Population density is measured as the number of individuals per unit area. A population's dispersion can be random, uniform, or clumped. Demographic factors include age structure, sex ratio, and life tables. Survivorship curves illustrate survival rates at different ages. Population growth can be exponential or logistic depending on environmental limits.
This document discusses several topics related to ecology and population biology, including:
1) It introduces the concepts of r-selected and K-selected species, which have different life history strategies related to population stability and resource availability.
2) It discusses different types of population growth patterns (exponential, logistic) and factors (density-dependent, density-independent) that influence population growth rates.
3) It provides examples of applying mathematical models to analyze population growth and examines survivorship curves and life tables used to study reproduction and mortality among species.
This presentation discusses life tables and their construction and applications. It notes that Edmond Halley was the first to construct a life table 300 years ago using a methodology still followed today with slight variations. A life table shows the lifespan of a hypothetical cohort from birth until all have died, and can be used to calculate survivorship to various ages, life expectancy, and for population projections. The presentation outlines the key components and assumptions of life tables as well as how they are constructed step-by-step using sample data.
Population ecology is the study of how population numbers change over time and the factors influencing those changes. Key factors influencing population growth include birth and death rates, carrying capacity, and density dependence. Exponential growth leads to rapid increases at low densities while logistic growth levels off as density approaches the environment's carrying capacity due to competition for limited resources. Population regulation involves both density-dependent factors like competition, disease, and predation as well as density-independent environmental factors.
It is as per the syllabus of M.Sc. NRM including detailed study of population ecology
It describes the meaning of population with respect to ecology and includes population attributes, dynamics, dispersal, Population growth models, survivorship curves and limitations.
It also entails factors that influence and regulate population growth on the basis of density.
This document provides an overview of key concepts in population ecology. It discusses characteristics of populations like size, density, and growth patterns. Two main types of population growth curves are described: exponential (J-shaped) and sigmoid (S-shaped). Population regulation depends on both density-dependent and density-independent factors. Life history theories explain reproductive strategies in r-selected and K-selected species adapted to different environmental conditions. The document concludes with references for further reading on topics in population ecology.
1. Population ecology is the study of populations in relation to their environment, including factors influencing population density, distribution, age structure, and size variations.
2. A population is defined as a group of the same species living in the same area. Population density and dispersion patterns are influenced by environmental and social factors.
3. Population growth and size are determined by the balance between birth and death rates. Populations typically follow a logistic growth model where growth slows as carrying capacity is approached.
1. Population ecology is the study of populations in relation to their environment, including factors influencing population size, density, age structure, and distribution.
2. A population is defined as a group of the same species living in the same area. Population density and dispersion patterns are influenced by birth, death, immigration and emigration rates.
3. Population growth models include exponential and logistic growth. Exponential growth is unlimited while logistic growth incorporates a carrying capacity, leading to an S-shaped growth curve.
GEOGRAPHY Population Ecology HSC MAHARASHTRATwinsIT2
1. Population ecology is the study of populations in relation to their environment, including factors influencing population size, density, age structure, and distribution.
2. A population is defined as a group of the same species living in the same area. Population density and dispersion patterns are influenced by birth, death, immigration and emigration rates.
3. Population growth models include exponential and logistic growth. Exponential growth is unlimited while logistic growth incorporates a carrying capacity, leading to an S-shaped growth curve.
The document summarizes the construction and applications of life tables. It discusses how Edmond Halley first developed the methodology in 1693 to analyze vital statistics data from Breslau, Germany. The summary describes the key components and assumptions of life tables, including how they are used to estimate average life expectancy, mortality rates by age, and survival rates. Life tables are a statistical tool for quantifying population health and modeling demographic trends.
Microbial interaction
Microorganisms interacts with each other and can be physically associated with another organisms in a variety of ways.
One organism can be located on the surface of another organism as an ectobiont or located within another organism as endobiont.
Microbial interaction may be positive such as mutualism, proto-cooperation, commensalism or may be negative such as parasitism, predation or competition
Types of microbial interaction
Positive interaction: mutualism, proto-cooperation, commensalism
Negative interaction: Ammensalism (antagonism), parasitism, predation, competition
I. Mutualism:
It is defined as the relationship in which each organism in interaction gets benefits from association. It is an obligatory relationship in which mutualist and host are metabolically dependent on each other.
Mutualistic relationship is very specific where one member of association cannot be replaced by another species.
Mutualism require close physical contact between interacting organisms.
Relationship of mutualism allows organisms to exist in habitat that could not occupied by either species alone.
Mutualistic relationship between organisms allows them to act as a single organism.
Examples of mutualism:
i. Lichens:
Lichens are excellent example of mutualism.
They are the association of specific fungi and certain genus of algae. In lichen, fungal partner is called mycobiont and algal partner is called
II. Syntrophism:
It is an association in which the growth of one organism either depends on or improved by the substrate provided by another organism.
In syntrophism both organism in association gets benefits.
Compound A
Utilized by population 1
Compound B
Utilized by population 2
Compound C
utilized by both Population 1+2
Products
In this theoretical example of syntrophism, population 1 is able to utilize and metabolize compound A, forming compound B but cannot metabolize beyond compound B without co-operation of population 2. Population 2is unable to utilize compound A but it can metabolize compound B forming compound C. Then both population 1 and 2 are able to carry out metabolic reaction which leads to formation of end product that neither population could produce alone.
Examples of syntrophism:
i. Methanogenic ecosystem in sludge digester
Methane produced by methanogenic bacteria depends upon interspecies hydrogen transfer by other fermentative bacteria.
Anaerobic fermentative bacteria generate CO2 and H2 utilizing carbohydrates which is then utilized by methanogenic bacteria (Methanobacter) to produce methane.
ii. Lactobacillus arobinosus and Enterococcus faecalis:
In the minimal media, Lactobacillus arobinosus and Enterococcus faecalis are able to grow together but not alone.
The synergistic relationship between E. faecalis and L. arobinosus occurs in which E. faecalis require folic acid
Population ecology is a field of scientific research that examines the dynamics of populations of living organisms within a given environment. It involves the study of various aspects of populations, including their growth, distribution, density, age structure, and the factors that affect these attributes. Key components of population ecology include:
Population Dynamics: Population ecologists study how the size of a population changes over time. This involves examining birth rates (natality), death rates (mortality), immigration, and emigration.
Population Distribution: Understanding how individuals in a population are spatially distributed is essential. Populations can be clumped, evenly dispersed, or randomly distributed in a habitat.
Population Density: This refers to the number of individuals of a species per unit area or volume of habitat. Population density can have significant ecological and environmental implications.
Age Structure: The age distribution within a population can provide insights into its growth potential and reproductive capacity. It can help in predicting future population trends.
Population Growth Models: Population ecologists use mathematical models to describe and predict population growth, such as exponential and logistic growth models.
Limiting Factors: Population growth is limited by various factors, including availability of resources, predation, competition, disease, and environmental conditions. Population ecologists study how these factors influence population dynamics.
Carrying Capacity: The carrying capacity of an environment is the maximum population size that can be sustained by available resources without causing environmental degradation or resource depletion.
Interactions: Populations do not exist in isolation. Interactions with other species, such as predation, competition, and mutualism, are essential considerations in population ecology.
Conservation and Management: Population ecology plays a critical role in the conservation and management of endangered species and ecosystems. It helps in making informed decisions to protect and sustainably manage populations.
Research Methods: Population ecologists employ various field and laboratory techniques, including population censuses, mark and recapture studies, and modeling, to gather data and understand population dynamics.
Application of life tables in insect pest managementchidanand4098
Life tables are used in insect pest management to track mortality rates across different life stages of a population. An ecologist constructs a life table by observing many individuals over time and recording offspring production, deaths, and mortality factors. This data is then summarized to calculate average mortality rates within each developmental stage. Life tables are useful for determining the key factors influencing population size changes and the stages when a population is most vulnerable. This information can be applied to pest control by focusing control methods during vulnerable stages.
I MSc II Semester - Characteristics of a population.pptaigil2
This document outlines the key characteristics of populations including: population density, natality (birth rate), mortality (death rate), population growth curves, age distribution through age pyramids, and population fluctuations. It defines these terms and describes how they are measured or expressed. For example, population density can be crude or ecological density and is calculated as the number of individuals divided by the area. Population growth follows either a sigmoid or J-shaped curve over time.
This document discusses various attributes of populations and population growth. It describes birth rate, death rate, population density, age distribution, and sex ratio as key attributes of populations. Population growth curves can take a sigmoid or S-shaped form, with phases of lag, acceleration, and plateau, or a J-shaped form with rapid exponential growth until environmental resistance increases. Population change over time is determined by the balance of births, deaths, immigration and emigration. The carrying capacity of the environment limits population growth.
This document discusses various population characteristics and dynamics. It defines a population as a group of the same species living together in a region. Population ecology studies populations and their interactions with the environment. Key population characteristics include density, natality, mortality, growth forms, and distribution. Density refers to the number of individuals per unit area or volume. Natality is birth rate and mortality is death rate. Other concepts covered include survivorship curves, dispersion patterns, age structure through age pyramids, and population dispersal through emigration, immigration, and migration.
1. The document discusses various levels of biological organization from the ecosystem level down to the molecular level, providing examples like the eucalyptus forest ecosystem and the flying fox population.
2. It then focuses on population ecology, defining key population features like size, density, dispersion, growth rates, and factors that influence population growth like immigration, emigration, birth rates and death rates.
3. Models of population growth are discussed, including exponential and logistic growth curves, and the concept of carrying capacity is introduced as the maximum population size supported by available resources.
Population ecology examines populations as units of study. A population has characteristics like density, size, age structure, and dispersion. The four basic population parameters that affect density are natality, mortality, immigration, and emigration. Techniques to estimate population density include using quadrats, capture-recapture methods, and calculating relative density with tools like traps or roadside counts. Life tables can describe mortality schedules by tracking age-specific cohort survival. Population growth rates depend on birth and death rates, and can be modeled exponentially or logistically depending on environmental constraints.
Population ecology is the study of populations in relation to their environment. It includes influences on population density, distribution, age structure, and variations in population size. Key attributes of populations include birth rate, death rate, population density, sex ratio, and age distribution. Population growth occurs when birth rate exceeds death rate, though populations are limited by environmental carrying capacity. Populations interact through neutral, positive (e.g. mutualism), and negative (e.g. competition, predation) interactions that influence community structure.
Population ecology is the study of populations in relation to their environment. It examines factors like population size, density, dispersion patterns, demographics, survivorship curves, and population growth. Population size is influenced by birth rate, death rate, immigration, and emigration. Population density is measured as the number of individuals per unit area. A population's dispersion can be random, uniform, or clumped. Demographic factors include age structure, sex ratio, and life tables. Survivorship curves illustrate survival rates at different ages. Population growth can be exponential or logistic depending on environmental limits.
This document discusses several topics related to ecology and population biology, including:
1) It introduces the concepts of r-selected and K-selected species, which have different life history strategies related to population stability and resource availability.
2) It discusses different types of population growth patterns (exponential, logistic) and factors (density-dependent, density-independent) that influence population growth rates.
3) It provides examples of applying mathematical models to analyze population growth and examines survivorship curves and life tables used to study reproduction and mortality among species.
This presentation discusses life tables and their construction and applications. It notes that Edmond Halley was the first to construct a life table 300 years ago using a methodology still followed today with slight variations. A life table shows the lifespan of a hypothetical cohort from birth until all have died, and can be used to calculate survivorship to various ages, life expectancy, and for population projections. The presentation outlines the key components and assumptions of life tables as well as how they are constructed step-by-step using sample data.
Population ecology is the study of how population numbers change over time and the factors influencing those changes. Key factors influencing population growth include birth and death rates, carrying capacity, and density dependence. Exponential growth leads to rapid increases at low densities while logistic growth levels off as density approaches the environment's carrying capacity due to competition for limited resources. Population regulation involves both density-dependent factors like competition, disease, and predation as well as density-independent environmental factors.
It is as per the syllabus of M.Sc. NRM including detailed study of population ecology
It describes the meaning of population with respect to ecology and includes population attributes, dynamics, dispersal, Population growth models, survivorship curves and limitations.
It also entails factors that influence and regulate population growth on the basis of density.
This document provides an overview of key concepts in population ecology. It discusses characteristics of populations like size, density, and growth patterns. Two main types of population growth curves are described: exponential (J-shaped) and sigmoid (S-shaped). Population regulation depends on both density-dependent and density-independent factors. Life history theories explain reproductive strategies in r-selected and K-selected species adapted to different environmental conditions. The document concludes with references for further reading on topics in population ecology.
1. Population ecology is the study of populations in relation to their environment, including factors influencing population density, distribution, age structure, and size variations.
2. A population is defined as a group of the same species living in the same area. Population density and dispersion patterns are influenced by environmental and social factors.
3. Population growth and size are determined by the balance between birth and death rates. Populations typically follow a logistic growth model where growth slows as carrying capacity is approached.
1. Population ecology is the study of populations in relation to their environment, including factors influencing population size, density, age structure, and distribution.
2. A population is defined as a group of the same species living in the same area. Population density and dispersion patterns are influenced by birth, death, immigration and emigration rates.
3. Population growth models include exponential and logistic growth. Exponential growth is unlimited while logistic growth incorporates a carrying capacity, leading to an S-shaped growth curve.
GEOGRAPHY Population Ecology HSC MAHARASHTRATwinsIT2
1. Population ecology is the study of populations in relation to their environment, including factors influencing population size, density, age structure, and distribution.
2. A population is defined as a group of the same species living in the same area. Population density and dispersion patterns are influenced by birth, death, immigration and emigration rates.
3. Population growth models include exponential and logistic growth. Exponential growth is unlimited while logistic growth incorporates a carrying capacity, leading to an S-shaped growth curve.
The document summarizes the construction and applications of life tables. It discusses how Edmond Halley first developed the methodology in 1693 to analyze vital statistics data from Breslau, Germany. The summary describes the key components and assumptions of life tables, including how they are used to estimate average life expectancy, mortality rates by age, and survival rates. Life tables are a statistical tool for quantifying population health and modeling demographic trends.
Similar to Life table / life cycle (Chitra ).pptx (20)
Microbial interaction
Microorganisms interacts with each other and can be physically associated with another organisms in a variety of ways.
One organism can be located on the surface of another organism as an ectobiont or located within another organism as endobiont.
Microbial interaction may be positive such as mutualism, proto-cooperation, commensalism or may be negative such as parasitism, predation or competition
Types of microbial interaction
Positive interaction: mutualism, proto-cooperation, commensalism
Negative interaction: Ammensalism (antagonism), parasitism, predation, competition
I. Mutualism:
It is defined as the relationship in which each organism in interaction gets benefits from association. It is an obligatory relationship in which mutualist and host are metabolically dependent on each other.
Mutualistic relationship is very specific where one member of association cannot be replaced by another species.
Mutualism require close physical contact between interacting organisms.
Relationship of mutualism allows organisms to exist in habitat that could not occupied by either species alone.
Mutualistic relationship between organisms allows them to act as a single organism.
Examples of mutualism:
i. Lichens:
Lichens are excellent example of mutualism.
They are the association of specific fungi and certain genus of algae. In lichen, fungal partner is called mycobiont and algal partner is called
II. Syntrophism:
It is an association in which the growth of one organism either depends on or improved by the substrate provided by another organism.
In syntrophism both organism in association gets benefits.
Compound A
Utilized by population 1
Compound B
Utilized by population 2
Compound C
utilized by both Population 1+2
Products
In this theoretical example of syntrophism, population 1 is able to utilize and metabolize compound A, forming compound B but cannot metabolize beyond compound B without co-operation of population 2. Population 2is unable to utilize compound A but it can metabolize compound B forming compound C. Then both population 1 and 2 are able to carry out metabolic reaction which leads to formation of end product that neither population could produce alone.
Examples of syntrophism:
i. Methanogenic ecosystem in sludge digester
Methane produced by methanogenic bacteria depends upon interspecies hydrogen transfer by other fermentative bacteria.
Anaerobic fermentative bacteria generate CO2 and H2 utilizing carbohydrates which is then utilized by methanogenic bacteria (Methanobacter) to produce methane.
ii. Lactobacillus arobinosus and Enterococcus faecalis:
In the minimal media, Lactobacillus arobinosus and Enterococcus faecalis are able to grow together but not alone.
The synergistic relationship between E. faecalis and L. arobinosus occurs in which E. faecalis require folic acid
Candidate young stellar objects in the S-cluster: Kinematic analysis of a sub...Sérgio Sacani
Context. The observation of several L-band emission sources in the S cluster has led to a rich discussion of their nature. However, a definitive answer to the classification of the dusty objects requires an explanation for the detection of compact Doppler-shifted Brγ emission. The ionized hydrogen in combination with the observation of mid-infrared L-band continuum emission suggests that most of these sources are embedded in a dusty envelope. These embedded sources are part of the S-cluster, and their relationship to the S-stars is still under debate. To date, the question of the origin of these two populations has been vague, although all explanations favor migration processes for the individual cluster members. Aims. This work revisits the S-cluster and its dusty members orbiting the supermassive black hole SgrA* on bound Keplerian orbits from a kinematic perspective. The aim is to explore the Keplerian parameters for patterns that might imply a nonrandom distribution of the sample. Additionally, various analytical aspects are considered to address the nature of the dusty sources. Methods. Based on the photometric analysis, we estimated the individual H−K and K−L colors for the source sample and compared the results to known cluster members. The classification revealed a noticeable contrast between the S-stars and the dusty sources. To fit the flux-density distribution, we utilized the radiative transfer code HYPERION and implemented a young stellar object Class I model. We obtained the position angle from the Keplerian fit results; additionally, we analyzed the distribution of the inclinations and the longitudes of the ascending node. Results. The colors of the dusty sources suggest a stellar nature consistent with the spectral energy distribution in the near and midinfrared domains. Furthermore, the evaporation timescales of dusty and gaseous clumps in the vicinity of SgrA* are much shorter ( 2yr) than the epochs covered by the observations (≈15yr). In addition to the strong evidence for the stellar classification of the D-sources, we also find a clear disk-like pattern following the arrangements of S-stars proposed in the literature. Furthermore, we find a global intrinsic inclination for all dusty sources of 60 ± 20◦, implying a common formation process. Conclusions. The pattern of the dusty sources manifested in the distribution of the position angles, inclinations, and longitudes of the ascending node strongly suggests two different scenarios: the main-sequence stars and the dusty stellar S-cluster sources share a common formation history or migrated with a similar formation channel in the vicinity of SgrA*. Alternatively, the gravitational influence of SgrA* in combination with a massive perturber, such as a putative intermediate mass black hole in the IRS 13 cluster, forces the dusty objects and S-stars to follow a particular orbital arrangement. Key words. stars: black holes– stars: formation– Galaxy: center– galaxies: star formation
(June 12, 2024) Webinar: Development of PET theranostics targeting the molecu...Scintica Instrumentation
Targeting Hsp90 and its pathogen Orthologs with Tethered Inhibitors as a Diagnostic and Therapeutic Strategy for cancer and infectious diseases with Dr. Timothy Haystead.
JAMES WEBB STUDY THE MASSIVE BLACK HOLE SEEDSSérgio Sacani
The pathway(s) to seeding the massive black holes (MBHs) that exist at the heart of galaxies in the present and distant Universe remains an unsolved problem. Here we categorise, describe and quantitatively discuss the formation pathways of both light and heavy seeds. We emphasise that the most recent computational models suggest that rather than a bimodal-like mass spectrum between light and heavy seeds with light at one end and heavy at the other that instead a continuum exists. Light seeds being more ubiquitous and the heavier seeds becoming less and less abundant due the rarer environmental conditions required for their formation. We therefore examine the different mechanisms that give rise to different seed mass spectrums. We show how and why the mechanisms that produce the heaviest seeds are also among the rarest events in the Universe and are hence extremely unlikely to be the seeds for the vast majority of the MBH population. We quantify, within the limits of the current large uncertainties in the seeding processes, the expected number densities of the seed mass spectrum. We argue that light seeds must be at least 103 to 105 times more numerous than heavy seeds to explain the MBH population as a whole. Based on our current understanding of the seed population this makes heavy seeds (Mseed > 103 M⊙) a significantly more likely pathway given that heavy seeds have an abundance pattern than is close to and likely in excess of 10−4 compared to light seeds. Finally, we examine the current state-of-the-art in numerical calculations and recent observations and plot a path forward for near-future advances in both domains.
PPT on Direct Seeded Rice presented at the three-day 'Training and Validation Workshop on Modules of Climate Smart Agriculture (CSA) Technologies in South Asia' workshop on April 22, 2024.
Authoring a personal GPT for your research and practice: How we created the Q...Leonel Morgado
Thematic analysis in qualitative research is a time-consuming and systematic task, typically done using teams. Team members must ground their activities on common understandings of the major concepts underlying the thematic analysis, and define criteria for its development. However, conceptual misunderstandings, equivocations, and lack of adherence to criteria are challenges to the quality and speed of this process. Given the distributed and uncertain nature of this process, we wondered if the tasks in thematic analysis could be supported by readily available artificial intelligence chatbots. Our early efforts point to potential benefits: not just saving time in the coding process but better adherence to criteria and grounding, by increasing triangulation between humans and artificial intelligence. This tutorial will provide a description and demonstration of the process we followed, as two academic researchers, to develop a custom ChatGPT to assist with qualitative coding in the thematic data analysis process of immersive learning accounts in a survey of the academic literature: QUAL-E Immersive Learning Thematic Analysis Helper. In the hands-on time, participants will try out QUAL-E and develop their ideas for their own qualitative coding ChatGPT. Participants that have the paid ChatGPT Plus subscription can create a draft of their assistants. The organizers will provide course materials and slide deck that participants will be able to utilize to continue development of their custom GPT. The paid subscription to ChatGPT Plus is not required to participate in this workshop, just for trying out personal GPTs during it.
The binding of cosmological structures by massless topological defectsSérgio Sacani
Assuming spherical symmetry and weak field, it is shown that if one solves the Poisson equation or the Einstein field
equations sourced by a topological defect, i.e. a singularity of a very specific form, the result is a localized gravitational
field capable of driving flat rotation (i.e. Keplerian circular orbits at a constant speed for all radii) of test masses on a thin
spherical shell without any underlying mass. Moreover, a large-scale structure which exploits this solution by assembling
concentrically a number of such topological defects can establish a flat stellar or galactic rotation curve, and can also deflect
light in the same manner as an equipotential (isothermal) sphere. Thus, the need for dark matter or modified gravity theory is
mitigated, at least in part.
Mending Clothing to Support Sustainable Fashion_CIMaR 2024.pdfSelcen Ozturkcan
Ozturkcan, S., Berndt, A., & Angelakis, A. (2024). Mending clothing to support sustainable fashion. Presented at the 31st Annual Conference by the Consortium for International Marketing Research (CIMaR), 10-13 Jun 2024, University of Gävle, Sweden.
Evidence of Jet Activity from the Secondary Black Hole in the OJ 287 Binary S...Sérgio Sacani
Wereport the study of a huge optical intraday flare on 2021 November 12 at 2 a.m. UT in the blazar OJ287. In the binary black hole model, it is associated with an impact of the secondary black hole on the accretion disk of the primary. Our multifrequency observing campaign was set up to search for such a signature of the impact based on a prediction made 8 yr earlier. The first I-band results of the flare have already been reported by Kishore et al. (2024). Here we combine these data with our monitoring in the R-band. There is a big change in the R–I spectral index by 1.0 ±0.1 between the normal background and the flare, suggesting a new component of radiation. The polarization variation during the rise of the flare suggests the same. The limits on the source size place it most reasonably in the jet of the secondary BH. We then ask why we have not seen this phenomenon before. We show that OJ287 was never before observed with sufficient sensitivity on the night when the flare should have happened according to the binary model. We also study the probability that this flare is just an oversized example of intraday variability using the Krakow data set of intense monitoring between 2015 and 2023. We find that the occurrence of a flare of this size and rapidity is unlikely. In machine-readable Tables 1 and 2, we give the full orbit-linked historical light curve of OJ287 as well as the dense monitoring sample of Krakow.
1. Life cycle
GOVERNMENT E. RAGHAVENDRA RAO PG SCIENCE COLLEGE,
BILASPUR (C.G.)
Department of zoology
Topic – Life table
Guided by -
Mr. Santosh Agrawal
Submitted by - Chitrakanta pendro
M.Sc. III semester
2. • The numerical data collected
during a population study can be
presented as a table of figures
known as Life Table.
• Life tables usually represent
data from cohort called cohort
life table). Two method of
constructing life table.
1. Dynamic Horizontal
2. Static or stationary vertical
Life cycle
3. • Dynamic
Horizontal
In this we start with a
known group of individuals
called cohort and observe
bow many die at each age
till all of them die. This
method of constructing life
table is called Dynamic
Horizontal.
Dynamic Horizontal
4. • Static or stationary
vertical
The other method is called
static or stationary vertical. In
this method a cross section of
population at given time is
taken and its age structure
related observation are taken.
Life
cycle
5. Example of Cohort Life Table
Where, Age (years) = x Proportion
of original cohort surviving to the
beginning of age class x = lx .
Proportion of original cohort dying
during age class x = dx Mortality
rate = qx
Life cycle
6. Example of Static Life Table
Static life Table for red deer hinds
on Rhum island. based on
reconstructed age structure of the
population in 1957 .
Life cycle
7. Individual fecundity or Age
Specific Birth Rate, m.
• It is the mean number of offspring
produced per individual or it is the
number of offspring that a given
female produces during a particular
age.
Gross Reproductive Rate (GRR)
GRR=∑mx Net Reproductive Rate (NRR)
Ro = ∑Ix.mx
Generation times
• It is the time lapse between birth of
the parent and the birth of the
Life cycle
9. 2. Survivorship Curve
• Cohort life table data are often shown
as a survivorship curve for a particular
particular population
• This is a graph showing the number of
individuals which survives through each
phase of life
• Pearl described 3 types of
survivorship curve
l. Type I or Convex Curve .
2. Type II or Diagonal straight line .
Survival curve
10. • Type I or Convex Curve:
In such population, there is little mortality until some age and then fairly steep mortality is
observed for example modem industrialized man, and many species of large animals.
• Type II or Diagonal straight line:
In such populations, mortality is constant at all age groups for example birds, rabbit and
mice, hydra, animals related to jellyfish etc.
• Type III or Concave curve
Such populations are characterized by high mortality during the young stage but
lower or nearly constant in the adult e.g. Oyster, most trees, many fishes and insects.
This appears to be the most common survivorship curve among animals and plants in
nature These types of survivorship curve are useful generalizations, but in practice,
patterns of survival are usually more complex. Thus, in a population of Erophila
verna, a very short-lived annual plant inhabiting sand dunes, survival can follow a
type I curve when the plants grow at low densities; a type II curve, at least until the
Survival
curve
11. Reference
E- P ODUM
BROTANICA ENCYCLOPEDIA
SOME ONLINE ARTICLES
https://www.youtube.com
/
https://www.google.
com/
Life cycle