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A Principle Governing The Success Of Populations.
The document proposes a new principle of population dynamics: that a population's success at growing alters the environment in ways that oppose further success. It outlines limitations of existing models like exponential growth and r/K selection theory, which do not account for extinction. The proposed alternative is based on two foundations: 1) variations in population size are due entirely to environmental factors, and 2) a population's impact on its environment increases with its size. A new differential equation is derived from this principle and shown to generate population change patterns similar to existing models but allowing for extinction.
The last major idea in population dynamics is the idea of a minimum .pdf
The last major idea in population dynamics is the idea of a minimum threshold for a species in a
habitat. For some species, survival is not possible if the population size gets too small because of
natural interdependence. (Keep in mind that this is over and above the minimum threshold of two
animals required for sexual reproduction.) A differential equation that models that situation is
dN/ dt = rN (1 N/ T )( 1 N/ K) where 0 < T < K. Based on your experiences so far, choose
appropriate values of r, T, and K and plot a slope field. (a) Convince yourself that your slope
field indeed models a population of animals that is subject to a minimum threshold in order to
survive. (b) Describe the stability of each equilibrium you see. (c) Investigate the affect of
harvesting on this population. Explain how harvesting affects the equilibria and include slope
fields to support your answer. (d) Draw a bifurcation diagram and point out the bifurcation point.
What does that mean in terms of harvesting?
Solution
Exponential development is the rate of growth of population in the presence of unlimited
resources. Exponential development is also know as Density independent growth.
dN/dt = rN
dN is the adjustment or change in population measure
\"r\" is rate of increment of population (births-passings)
Logistic growth is the rate of development of populace when resources are constrained. The
growth is named as density dependent growth.
We represent the logistic growth by Sigmoidal or S-formed growth bend or curve.
dN/dt = rN [1-N/K]; where K is the carrying capacity
Carrying capacity is basically the maximum size of the population supported by the environment.
The development in populace stops at K.
The natural or environmental components modify and make the K to change.
a) Natural growth equation more genereally represented as
P(t) = P0 * ert
where P is the populace at given time t and r is the rate of development of populace
Logistic Growth dependably will exist in between carrying capacity, K and it will indicate S
formed development curve while exponential development or growth seems to move higher.
This development pattern is found in populaces that have entry to constrained resources. The
loest populace develops exponentially at first. Be that as it may, when the constrained resources
begin demonstrating their effects the development or growth slows down and achieves a the
carrying capacity or limiting value.
b) Logistic growth demonstrates discrete and continuous development models.
The discrete model demonstrates that populace development is reliant on most extreme rate of
development, carrying capacity, and rate of per-capita increment of the populace. Logistic
growth is ceaseless when the individual imitates at the rate that decreases as a linear function of
size of populace.
Equation for persistent model is dN/dt = r*N (1-N/K)
In populaces that are lower than K will increment in size while that are higher than K will
diminish in size. K will stay stea.
PopulationEcology52.ppt
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 MAHARASHTRA
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.
Exponential and Logistics Growth Curve - Environmental Science
This document discusses exponential and logistic population growth models. Exponential growth occurs when a population's growth rate remains constant regardless of population size, producing a J-shaped curve. Logistic growth accounts for environmental constraints, with the growth rate decreasing as the population approaches the carrying capacity, producing an S-shaped curve. Key factors like resources, space, food and shelter determine a population's carrying capacity.
Population.ppt
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.
Population ecology
This document provides an overview of key concepts in population ecology, including:
- Defining populations and population ecology
- Describing different population distribution patterns and survivorship curves
- Comparing exponential and logistic growth models and the concept of carrying capacity
- Distinguishing between density-dependent and density-independent factors
- Contrasting r-selected and K-selected life history strategies
- Discussing factors that influence population size such as birth and death rates
Duckweed LabAn Experimental Study of Population Growth Introd.docx
Duckweed Lab:
An Experimental Study of Population Growth
Introduction (3/2 or 3/3)
How populations change over time, using genetics, allows us to understand how microevolution works. To understand the ecology of a population, we need to know how they grow or decline. There are two components that need to be considered in studying population growth. First is the data collection. Gathering data on an existing population and documenting the number of births and deaths can give us a picture of what is actually going on in the population. We can see if the population is growing or shrinking. The second component is using the data to model and predict how the population will grow or shrink in the future. Thus, understanding population growth has important implications in terms of conservation and management.
How a population grows or declines can easily be determined by counting the number of births and deaths in a given time. This can be determined by using the following equation:
∆𝑁
∆𝑡 = 𝐵 − 𝐷
Where DN/Dt is the change in population size (N) over a given time (t). B is the number of births and D is the number of deaths, which is easy enough. However, this information is limited. It can only tell us what is going on now (what we are actually observing and what has occurred in the past), but it will not allow us to predict what will happen in the future. To be able to do this, we need to determine the birth and death rates per capita (or per individual). The per capita birth and death rates are symbolized by b and d, respectively. These rates are multiplied by the population number (N) because birth and death relies on how many individuals are in a population. Thus, the equation above can be modified to the following equation:
∆𝑁
∆𝑡 =𝑏𝑁−𝑑𝑁
Now, the above formula can be simplified if we assume r to equal b – d as the per capita growth rate. Additionally, it would be helpful if we can determine the growth rate in very short time frames. This is because populations fluctuate regularly such that the growth rate in the first year may not the same as the growth rate in the second year. Thus, we can further modify the above equation to the following:
𝑑𝑁
𝑑𝑡 = 𝑟𝑁
Let’s assume, in a population, that the same amount of individuals are born (b) and die (d). This means that r = 0. If r = 0, then 0 * N is 0. This means that the population is not growing, and whatever N was will stay the same. If we assume that there are more individuals dying than are being born, this means that r < 0 (some negative number). This means that the population will decline. For example, if the birth rate is 0.5 and the death rate is 1, this will result in r being -0.5. This means that in a population of 100, dN/dt = -0.5 * 100 = -50, which leads to the population decreasing in size by 50 individuals (100 – 50 = 50). In contrast, if the birth rate is greater than
BIOL251 Spring 2020 Updated 12/03/20 Alejandrino 1
Duckweed Lab:
An Experimental Study of Population
Recommended
A Principle Governing The Success Of Populations.
The document proposes a new principle of population dynamics: that a population's success at growing alters the environment in ways that oppose further success. It outlines limitations of existing models like exponential growth and r/K selection theory, which do not account for extinction. The proposed alternative is based on two foundations: 1) variations in population size are due entirely to environmental factors, and 2) a population's impact on its environment increases with its size. A new differential equation is derived from this principle and shown to generate population change patterns similar to existing models but allowing for extinction.
The last major idea in population dynamics is the idea of a minimum .pdf
The last major idea in population dynamics is the idea of a minimum threshold for a species in a
habitat. For some species, survival is not possible if the population size gets too small because of
natural interdependence. (Keep in mind that this is over and above the minimum threshold of two
animals required for sexual reproduction.) A differential equation that models that situation is
dN/ dt = rN (1 N/ T )( 1 N/ K) where 0 < T < K. Based on your experiences so far, choose
appropriate values of r, T, and K and plot a slope field. (a) Convince yourself that your slope
field indeed models a population of animals that is subject to a minimum threshold in order to
survive. (b) Describe the stability of each equilibrium you see. (c) Investigate the affect of
harvesting on this population. Explain how harvesting affects the equilibria and include slope
fields to support your answer. (d) Draw a bifurcation diagram and point out the bifurcation point.
What does that mean in terms of harvesting?
Solution
Exponential development is the rate of growth of population in the presence of unlimited
resources. Exponential development is also know as Density independent growth.
dN/dt = rN
dN is the adjustment or change in population measure
\"r\" is rate of increment of population (births-passings)
Logistic growth is the rate of development of populace when resources are constrained. The
growth is named as density dependent growth.
We represent the logistic growth by Sigmoidal or S-formed growth bend or curve.
dN/dt = rN [1-N/K]; where K is the carrying capacity
Carrying capacity is basically the maximum size of the population supported by the environment.
The development in populace stops at K.
The natural or environmental components modify and make the K to change.
a) Natural growth equation more genereally represented as
P(t) = P0 * ert
where P is the populace at given time t and r is the rate of development of populace
Logistic Growth dependably will exist in between carrying capacity, K and it will indicate S
formed development curve while exponential development or growth seems to move higher.
This development pattern is found in populaces that have entry to constrained resources. The
loest populace develops exponentially at first. Be that as it may, when the constrained resources
begin demonstrating their effects the development or growth slows down and achieves a the
carrying capacity or limiting value.
b) Logistic growth demonstrates discrete and continuous development models.
The discrete model demonstrates that populace development is reliant on most extreme rate of
development, carrying capacity, and rate of per-capita increment of the populace. Logistic
growth is ceaseless when the individual imitates at the rate that decreases as a linear function of
size of populace.
Equation for persistent model is dN/dt = r*N (1-N/K)
In populaces that are lower than K will increment in size while that are higher than K will
diminish in size. K will stay stea.
PopulationEcology52.ppt
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 MAHARASHTRA
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.
Exponential and Logistics Growth Curve - Environmental Science
This document discusses exponential and logistic population growth models. Exponential growth occurs when a population's growth rate remains constant regardless of population size, producing a J-shaped curve. Logistic growth accounts for environmental constraints, with the growth rate decreasing as the population approaches the carrying capacity, producing an S-shaped curve. Key factors like resources, space, food and shelter determine a population's carrying capacity.
Population.ppt
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.
Population ecology
This document provides an overview of key concepts in population ecology, including:
- Defining populations and population ecology
- Describing different population distribution patterns and survivorship curves
- Comparing exponential and logistic growth models and the concept of carrying capacity
- Distinguishing between density-dependent and density-independent factors
- Contrasting r-selected and K-selected life history strategies
- Discussing factors that influence population size such as birth and death rates
Duckweed LabAn Experimental Study of Population Growth Introd.docx
Duckweed Lab:
An Experimental Study of Population Growth
Introduction (3/2 or 3/3)
How populations change over time, using genetics, allows us to understand how microevolution works. To understand the ecology of a population, we need to know how they grow or decline. There are two components that need to be considered in studying population growth. First is the data collection. Gathering data on an existing population and documenting the number of births and deaths can give us a picture of what is actually going on in the population. We can see if the population is growing or shrinking. The second component is using the data to model and predict how the population will grow or shrink in the future. Thus, understanding population growth has important implications in terms of conservation and management.
How a population grows or declines can easily be determined by counting the number of births and deaths in a given time. This can be determined by using the following equation:
∆𝑁
∆𝑡 = 𝐵 − 𝐷
Where DN/Dt is the change in population size (N) over a given time (t). B is the number of births and D is the number of deaths, which is easy enough. However, this information is limited. It can only tell us what is going on now (what we are actually observing and what has occurred in the past), but it will not allow us to predict what will happen in the future. To be able to do this, we need to determine the birth and death rates per capita (or per individual). The per capita birth and death rates are symbolized by b and d, respectively. These rates are multiplied by the population number (N) because birth and death relies on how many individuals are in a population. Thus, the equation above can be modified to the following equation:
∆𝑁
∆𝑡 =𝑏𝑁−𝑑𝑁
Now, the above formula can be simplified if we assume r to equal b – d as the per capita growth rate. Additionally, it would be helpful if we can determine the growth rate in very short time frames. This is because populations fluctuate regularly such that the growth rate in the first year may not the same as the growth rate in the second year. Thus, we can further modify the above equation to the following:
𝑑𝑁
𝑑𝑡 = 𝑟𝑁
Let’s assume, in a population, that the same amount of individuals are born (b) and die (d). This means that r = 0. If r = 0, then 0 * N is 0. This means that the population is not growing, and whatever N was will stay the same. If we assume that there are more individuals dying than are being born, this means that r < 0 (some negative number). This means that the population will decline. For example, if the birth rate is 0.5 and the death rate is 1, this will result in r being -0.5. This means that in a population of 100, dN/dt = -0.5 * 100 = -50, which leads to the population decreasing in size by 50 individuals (100 – 50 = 50). In contrast, if the birth rate is greater than
BIOL251 Spring 2020 Updated 12/03/20 Alejandrino 1
Duckweed Lab:
An Experimental Study of Population
Population dynamics
- Population growth is determined by birth, death, immigration, and emigration rates and can take the form of exponential or logistic growth.
- Exponential growth occurs when resources are unlimited, while logistic growth occurs when resources become limited, causing the population to level off at the carrying capacity of the environment.
- Population regulation occurs through density-dependent factors like competition and disease, which increase mortality at high population densities, and density-independent factors like weather.
- R-strategist species are adapted to unstable environments through high reproduction rates, small body size, and short lifespans. K-strategist species are adapted to stable environments through slower growth, larger body size, and investment in fewer offspring.
Ch 36 ppt
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.
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The document discusses various topics related to population biology, including:
1) Factors that affect population growth rates such as births, deaths, immigration and emigration. Population growth can be exponential or logistic depending on resource availability.
2) Population regulation through density-dependent and density-independent factors such as competition, disease, and environmental conditions.
3) Conservation biology concepts including minimum viable populations, genetic diversity, metapopulations, and population viability analysis.
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This document summarizes a study that used kinetic Monte Carlo simulation and mathematical modeling to explore the dynamics and long-term behavior of susceptible and resistant bacterial populations under different transformation mechanisms. The study found that the dominant population depends on the transformation rate and mechanism. With a constant transformation rate, the populations reach a steady state. With a linear mechanism where plasmids are not replenished, the susceptible population dominates. With a recycled mechanism where plasmids are returned after resistant bacteria die, the resistant population can eventually outgrow the susceptible population due to sustained plasmid abundance.
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Population ecology studies how organism numbers change over time and space and the factors influencing these changes. Key concepts include:
- Populations are groups of the same species in a defined area, with measures including population density and dispersion patterns.
- Populations can grow exponentially if birth and death rates remain constant, but density dependence causes logistic/sigmoidal growth towards an equilibrium carrying capacity K.
- Life histories vary along an r-K continuum, with r-selected populations having high reproduction and mortality and K-selected having lower reproduction but higher survival and competition.
- Capture-recapture methods can estimate unknown population sizes using marked and recaptured individuals.
Population ecology
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.
Environmental Science-4.pptx
This document provides an overview of population ecology concepts including population size, density, growth, and models. It defines a population as a group of the same species living in the same area. Population ecology studies how populations interact with their environment and change over time. Populations can be characterized by size, density, dispersion, age structure, and sex ratio. The document discusses exponential and logistic population growth models. Exponential growth occurs when resources are unlimited, while logistic growth occurs when resources are limited, causing the growth rate to slow as the population approaches the environment's carrying capacity. Examples are provided to illustrate exponential and logistic growth patterns over time.
Grade 10 - Population Ecology
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.
Ch 6 ed
The document discusses several key concepts in population biology including:
1) Factors that affect population growth such as biotic potential, birth and death rates, immigration and emigration.
2) Models for describing population growth patterns including exponential, logistic, r-selected and K-selected species.
3) Factors that regulate population growth including density-dependent and density-independent factors as well as abiotic and biotic influences.
4) Conservation biology concepts such as minimum viable population size, genetic diversity, and metapopulation structure.
Modelling of Bacterial Growth
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Baranyi Model
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populationecology-120221024008-phpapp02.pdf
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.
1307 population ecology f19 blank
This document provides an overview of key concepts in population ecology, including definitions of population and population density. It describes different forms of population distribution and survivorship curves. Exponential and logistic population growth models are explained. The roles of birth rate, death rate, carrying capacity, and life history adaptations like r-selected and K-selected strategies are summarized. Human population growth is also briefly discussed.
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The document summarizes a stochastic population viability analysis for rare large-bodied woodpecker species conducted to determine the implications for the endangered Ivory-billed Woodpecker. The study developed a population model to predict extinction rates under varying scenarios of demographic rates, population size, environmental stochasticity, and Allee effects. The results showed that maintaining intermediate or high survival and fecundity rates could allow populations as small as 5 individuals to persist, even with environmental variation and Allee effects, implying rare woodpecker species may have survived in small numbers until modern times given sufficient habitat quality.
Population dynamics
1) Survivorship curves classify populations into three types based on mortality rates - Type I has low mortality until old age, Type II has steady mortality throughout life, Type III has high early mortality but low later mortality.
2) Population growth occurs when birth rates exceed death rates. The per capita rate of increase (r) indicates if a population is growing (r > 0) or declining (r < 0).
3) Logistic population growth limits exponential growth by incorporating a carrying capacity (K), producing a sigmoid growth curve as population size approaches K.
Top of Form1. Stream quality is based on the levels of many .docx
Top of Form
1.
Stream quality is based on the levels of many variables, including the following. Which of these variables is quantitative?
The amount of dissolved oxygen
The number of distinct species present
The amount of phosphorus
All of the above
2.
Which of the following is a discrete variable?
Weight of a fish
Length of a fish
None of the above
Number of toxins present in a fish
3.
During winter, red foxes hunt small rodents by jumping into thick snow cover. Researchers report that a hunting trip lasts on average 19 minutes and involves on average 7 jumps. They also report that, surprisingly, 79% of all successful jumps are made in the northeast direction. Three variables are mentioned in this report. The first variable mentioned is
ordinal.
quantitative and discrete.
quantitative and continuous.
categorical.
4.
A sample of 55 streams in severe distress was obtained during 2007. The following is a bar graph of the number of streams that are from the Northeast, Northwest, Southeast, or Southwest. In the bar graph, the bar for the Northeast has been omitted.
The number of streams from the Northeast is
35.
25.
15.
45.
5.
Here is a stemplot (with split stems) of body temperatures (in degrees Fahrenheit) for 65 healthy adult women.
The first quartile for this data set is
97.6.
97.5.
98.0.
97.9.
6.
Researchers measured the length of the central retrix (R1), a flight-involved tail feather, in 21 female long-tailed finches. Here is a boxplot of the length, in millimeters (mm).
Based on this boxplot, which of the following statements is TRUE?
The distribution of R1 lengths is bimodal.
The distribution of R1 lengths is mildly right-skewed with a high outlier.
75% of the birds in this study had an R1 length above 70 mm.
All of the above
7.
Geckos are lizards with specialized toe pads that enable them to easily climb all sorts of surfaces. A research team examined the adhesive properties of 7 Tokay geckos. Below are their toe-pad areas (in square centimeters, cm2).
5.6
4.9
6.0
5.1
5.5
5.1
7.5
To be an outlier, an observation must fall outside the range
4.9 to 7.5.
4.2 to 6.9.
3.75 to 7.35.
5.1 to 6.0.
8.
The median age of five people on a committee is 30 years. One of the members, whose age is 50 years, resigns. The median age of the remaining four people in the committee is
not able to be determined from the information given.
25 years.
30 years.
40 years.
9.
By inspection, determine which of the following sets of numbers has the smallest standard deviation.
7, 8, 9, 10
0, 0, 10, 10
0, 1, 2, 3
5, 5, 5, 5
10.
The volume of oxygen consumed (in liters per minute) while a person is at rest and while he or she is exercising (running on a treadmill) was measured for each of 50 subjects. The goal is to determine if the volume of oxygen consumed during aerobic exercise can be estimated from the amount consumed at rest. The results are plotted below.
The scatterplot sugges ...
Part 2- Human Population- Ecologists often think about the dynamics o.pdf
Part 2: Human Population. Ecologists often think about the dynamics of populations and what
that reveals about the biology of an organism. The size of a population of an organism is
controlled by many factors both intrinsic to an organism (time for generations, body size, number
of offspring, environmental tolerances, and diet) and extrinsic in terms of the ecosystem (amount
of food, amount of competitors, amount of predators/pathogens/parasites) and environment
(favorable climate, available space, climate variability, and frequency of catastrophic events).
Understanding this complicated system can be simplified using a mathematical formula, which
helps to conceptualize the factors controlling the size of a population.
dN/dt is the amount of change in a population over time
r is the rate of population growth (bigger r means faster growth)
N is the current population size
K is the Carrying Capacity, which is the number of individuals the environment can support.
We can use this equation to compare organisms. For instance, we can think about animals whose
population is controlled by the r term (r-selected), whose population can grow extremely fast, but
often they have population crashes as well. Alternatively, there can be populations controlled by
the K term (k-selected) that have slower population growth but are adapted to maintain
populations right at the carrying capacity.
6) Brainstorm animals that would be good examples of r- selected or k- selected. How might
their biology differ?.
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Brief idea on the Impact of ongoing human development on our environment and Describing and understanding population ecology - Patterns of dispersion, Survivorship curve, Population growth, Exponential growth, ecological footprint etc
fish population dynamics, Population structure
Estimation of fish population dynamics are often based on age structures. Understanding past
population structure is of interest to evolutionary biologists because it can reveal when migration
regimes changed in natural populations, thereby pointing to potential environmental factors such as
climate changes as driving evolutionary forces. Characterizing the structure of extent populations is also
key to conservation genetics as translocation or reintroduction decisions must preserve evolutionary
stable units. Finally, population structure has important biomedical consequences either when a number
of subpopulation groups is locally adapted to particular environmental conditions (and maladapted
when exposed to new environments) or represents a confounding factor in the study of the statistical
association between genetic variants and phenotyp
Population dynamics
Populations have characteristics like population size, density, age distribution, and dispersion that can change over time. A population's growth is determined by births and immigration minus deaths and emigration. Exponential growth occurs when births exceed deaths, but resources are ultimately limited by the environment's carrying capacity. Population growth models like the logistic model account for this carrying capacity and better represent real populations than unlimited exponential growth. Different species have evolved r-selection or K-selection reproductive strategies to cope with changing environments and population pressures.
Population dynamics
Populations have characteristics like population size, density, age distribution, and dispersion that can change over time. A population's growth is determined by births and immigration minus deaths and emigration. Exponential growth occurs when births exceed deaths, but resources are ultimately limited by the environment's carrying capacity. Populations may exhibit r-selected or K-selected reproductive strategies depending on environmental pressures and resource availability.
RPMS TEMPLATE FOR SCHOOL YEAR 2023-2024 FOR TEACHER 1 TO TEACHER 3
RPMS Template 2023-2024 by: Irene S. Rueco
The History of Stoke Newington Street Names
Presented at the Stoke Newington Literary Festival on 9th June 2024
www.StokeNewingtonHistory.com
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Population dynamics
- Population growth is determined by birth, death, immigration, and emigration rates and can take the form of exponential or logistic growth.
- Exponential growth occurs when resources are unlimited, while logistic growth occurs when resources become limited, causing the population to level off at the carrying capacity of the environment.
- Population regulation occurs through density-dependent factors like competition and disease, which increase mortality at high population densities, and density-independent factors like weather.
- R-strategist species are adapted to unstable environments through high reproduction rates, small body size, and short lifespans. K-strategist species are adapted to stable environments through slower growth, larger body size, and investment in fewer offspring.
Ch 36 ppt
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.
Chapt06 lecture
The document discusses various topics related to population biology, including:
1) Factors that affect population growth rates such as births, deaths, immigration and emigration. Population growth can be exponential or logistic depending on resource availability.
2) Population regulation through density-dependent and density-independent factors such as competition, disease, and environmental conditions.
3) Conservation biology concepts including minimum viable populations, genetic diversity, metapopulations, and population viability analysis.
poster
This document summarizes a study that used kinetic Monte Carlo simulation and mathematical modeling to explore the dynamics and long-term behavior of susceptible and resistant bacterial populations under different transformation mechanisms. The study found that the dominant population depends on the transformation rate and mechanism. With a constant transformation rate, the populations reach a steady state. With a linear mechanism where plasmids are not replenished, the susceptible population dominates. With a recycled mechanism where plasmids are returned after resistant bacteria die, the resistant population can eventually outgrow the susceptible population due to sustained plasmid abundance.
14 (2013).pptx
Population ecology studies how organism numbers change over time and space and the factors influencing these changes. Key concepts include:
- Populations are groups of the same species in a defined area, with measures including population density and dispersion patterns.
- Populations can grow exponentially if birth and death rates remain constant, but density dependence causes logistic/sigmoidal growth towards an equilibrium carrying capacity K.
- Life histories vary along an r-K continuum, with r-selected populations having high reproduction and mortality and K-selected having lower reproduction but higher survival and competition.
- Capture-recapture methods can estimate unknown population sizes using marked and recaptured individuals.
Population ecology
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.
Environmental Science-4.pptx
This document provides an overview of population ecology concepts including population size, density, growth, and models. It defines a population as a group of the same species living in the same area. Population ecology studies how populations interact with their environment and change over time. Populations can be characterized by size, density, dispersion, age structure, and sex ratio. The document discusses exponential and logistic population growth models. Exponential growth occurs when resources are unlimited, while logistic growth occurs when resources are limited, causing the growth rate to slow as the population approaches the environment's carrying capacity. Examples are provided to illustrate exponential and logistic growth patterns over time.
Grade 10 - Population Ecology
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.
Ch 6 ed
The document discusses several key concepts in population biology including:
1) Factors that affect population growth such as biotic potential, birth and death rates, immigration and emigration.
2) Models for describing population growth patterns including exponential, logistic, r-selected and K-selected species.
3) Factors that regulate population growth including density-dependent and density-independent factors as well as abiotic and biotic influences.
4) Conservation biology concepts such as minimum viable population size, genetic diversity, and metapopulation structure.
Modelling of Bacterial Growth
Modeling and parameter estimation of bacterial growth.
Baranyi Model
Three-Phase linear Model
Richards’ Model
Weibull Model
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Gompertz Model
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populationecology-120221024008-phpapp02.pdf
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.
1307 population ecology f19 blank
This document provides an overview of key concepts in population ecology, including definitions of population and population density. It describes different forms of population distribution and survivorship curves. Exponential and logistic population growth models are explained. The roles of birth rate, death rate, carrying capacity, and life history adaptations like r-selected and K-selected strategies are summarized. Human population growth is also briefly discussed.
Mattsson et al lbwo pva v2
The document summarizes a stochastic population viability analysis for rare large-bodied woodpecker species conducted to determine the implications for the endangered Ivory-billed Woodpecker. The study developed a population model to predict extinction rates under varying scenarios of demographic rates, population size, environmental stochasticity, and Allee effects. The results showed that maintaining intermediate or high survival and fecundity rates could allow populations as small as 5 individuals to persist, even with environmental variation and Allee effects, implying rare woodpecker species may have survived in small numbers until modern times given sufficient habitat quality.
Population dynamics
1) Survivorship curves classify populations into three types based on mortality rates - Type I has low mortality until old age, Type II has steady mortality throughout life, Type III has high early mortality but low later mortality.
2) Population growth occurs when birth rates exceed death rates. The per capita rate of increase (r) indicates if a population is growing (r > 0) or declining (r < 0).
3) Logistic population growth limits exponential growth by incorporating a carrying capacity (K), producing a sigmoid growth curve as population size approaches K.
Top of Form1. Stream quality is based on the levels of many .docx
Top of Form
1.
Stream quality is based on the levels of many variables, including the following. Which of these variables is quantitative?
The amount of dissolved oxygen
The number of distinct species present
The amount of phosphorus
All of the above
2.
Which of the following is a discrete variable?
Weight of a fish
Length of a fish
None of the above
Number of toxins present in a fish
3.
During winter, red foxes hunt small rodents by jumping into thick snow cover. Researchers report that a hunting trip lasts on average 19 minutes and involves on average 7 jumps. They also report that, surprisingly, 79% of all successful jumps are made in the northeast direction. Three variables are mentioned in this report. The first variable mentioned is
ordinal.
quantitative and discrete.
quantitative and continuous.
categorical.
4.
A sample of 55 streams in severe distress was obtained during 2007. The following is a bar graph of the number of streams that are from the Northeast, Northwest, Southeast, or Southwest. In the bar graph, the bar for the Northeast has been omitted.
The number of streams from the Northeast is
35.
25.
15.
45.
5.
Here is a stemplot (with split stems) of body temperatures (in degrees Fahrenheit) for 65 healthy adult women.
The first quartile for this data set is
97.6.
97.5.
98.0.
97.9.
6.
Researchers measured the length of the central retrix (R1), a flight-involved tail feather, in 21 female long-tailed finches. Here is a boxplot of the length, in millimeters (mm).
Based on this boxplot, which of the following statements is TRUE?
The distribution of R1 lengths is bimodal.
The distribution of R1 lengths is mildly right-skewed with a high outlier.
75% of the birds in this study had an R1 length above 70 mm.
All of the above
7.
Geckos are lizards with specialized toe pads that enable them to easily climb all sorts of surfaces. A research team examined the adhesive properties of 7 Tokay geckos. Below are their toe-pad areas (in square centimeters, cm2).
5.6
4.9
6.0
5.1
5.5
5.1
7.5
To be an outlier, an observation must fall outside the range
4.9 to 7.5.
4.2 to 6.9.
3.75 to 7.35.
5.1 to 6.0.
8.
The median age of five people on a committee is 30 years. One of the members, whose age is 50 years, resigns. The median age of the remaining four people in the committee is
not able to be determined from the information given.
25 years.
30 years.
40 years.
9.
By inspection, determine which of the following sets of numbers has the smallest standard deviation.
7, 8, 9, 10
0, 0, 10, 10
0, 1, 2, 3
5, 5, 5, 5
10.
The volume of oxygen consumed (in liters per minute) while a person is at rest and while he or she is exercising (running on a treadmill) was measured for each of 50 subjects. The goal is to determine if the volume of oxygen consumed during aerobic exercise can be estimated from the amount consumed at rest. The results are plotted below.
The scatterplot sugges ...
Part 2- Human Population- Ecologists often think about the dynamics o.pdf
Part 2: Human Population. Ecologists often think about the dynamics of populations and what
that reveals about the biology of an organism. The size of a population of an organism is
controlled by many factors both intrinsic to an organism (time for generations, body size, number
of offspring, environmental tolerances, and diet) and extrinsic in terms of the ecosystem (amount
of food, amount of competitors, amount of predators/pathogens/parasites) and environment
(favorable climate, available space, climate variability, and frequency of catastrophic events).
Understanding this complicated system can be simplified using a mathematical formula, which
helps to conceptualize the factors controlling the size of a population.
dN/dt is the amount of change in a population over time
r is the rate of population growth (bigger r means faster growth)
N is the current population size
K is the Carrying Capacity, which is the number of individuals the environment can support.
We can use this equation to compare organisms. For instance, we can think about animals whose
population is controlled by the r term (r-selected), whose population can grow extremely fast, but
often they have population crashes as well. Alternatively, there can be populations controlled by
the K term (k-selected) that have slower population growth but are adapted to maintain
populations right at the carrying capacity.
6) Brainstorm animals that would be good examples of r- selected or k- selected. How might
their biology differ?.
Effect of development on environment and population ecology
Brief idea on the Impact of ongoing human development on our environment and Describing and understanding population ecology - Patterns of dispersion, Survivorship curve, Population growth, Exponential growth, ecological footprint etc
fish population dynamics, Population structure
Estimation of fish population dynamics are often based on age structures. Understanding past
population structure is of interest to evolutionary biologists because it can reveal when migration
regimes changed in natural populations, thereby pointing to potential environmental factors such as
climate changes as driving evolutionary forces. Characterizing the structure of extent populations is also
key to conservation genetics as translocation or reintroduction decisions must preserve evolutionary
stable units. Finally, population structure has important biomedical consequences either when a number
of subpopulation groups is locally adapted to particular environmental conditions (and maladapted
when exposed to new environments) or represents a confounding factor in the study of the statistical
association between genetic variants and phenotyp
Population dynamics
Populations have characteristics like population size, density, age distribution, and dispersion that can change over time. A population's growth is determined by births and immigration minus deaths and emigration. Exponential growth occurs when births exceed deaths, but resources are ultimately limited by the environment's carrying capacity. Population growth models like the logistic model account for this carrying capacity and better represent real populations than unlimited exponential growth. Different species have evolved r-selection or K-selection reproductive strategies to cope with changing environments and population pressures.
Population dynamics
Populations have characteristics like population size, density, age distribution, and dispersion that can change over time. A population's growth is determined by births and immigration minus deaths and emigration. Exponential growth occurs when births exceed deaths, but resources are ultimately limited by the environment's carrying capacity. Populations may exhibit r-selected or K-selected reproductive strategies depending on environmental pressures and resource availability.
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popgrowth.ppt
- 1. Population Growth Exponential: Continuous addition of births and deaths at constant rates (b & d) Such that r = b - d Problem: no explicit prediction is made Solution: isolate N terms on left, and integrate
- 2. Result of the integration: r=0.05
- 3. Exponential growth relationships Slope of this curve Increases with density Slope of Curve on left Density Slope of line = r
- 4. Exponential growth, log scale Linear increase of log values with time is a sign of exponential growth
- 5. Geometric Growth Time is measured in discrete (contant) chunks Simplest approach: Generations are the time unit R0: Average number of offspring produced per individual, per lifetime-- Factor that a population will be multiplied by for each generation. Often called the Net Rate of Increase. Time is measured in generations in this equation.
- 6. Relationship between R0 and r A population growing for one generation should show the same result using either of the following equations: Continuous, where t=t (t = “generation time”) Discrete, where T=1 generation If these give the same result, then
- 7. R0 and r So! Information about R and t can lead us to r
- 8. Ways of finding R0 and t
- 9. Cohort study
- 14. Approximate r
- 15. Assumptions of exponential or geometric growth projections Constant lx and mx schedules This implies that reproduction and survival will not change with density This also implies that any changes in physical or chemical environment have no influence on survival or reproduction No important interactions with other species if age-specific data are used, assume stable age distribution.
- 16. Suppose we let lx, mx and t vary with density Bottom line: let r (per capita growth rate) vary with N dN/Ndt N r K 0 0
- 17. Density-dependent growth dN/Ndt N r K -r/K Y = A + BX 0 0
- 19. Human rates of change vs N
- 20. Projection based on Logistic model:
- 21. Earlier US projection, similar approach:
- 22. Logistic Examples Full-loop (2x the bacteria) Half-loop (half that on right) Paramecium, 2 species, growing for 8 days at high <r> and low <l> resource levels. Scale has been stretched on right to be equivalent to that on the left
- 23. More logistic examples Growth of a zooplankton crust- acean, Moina, at different temperatures Growth of flour beetles in flower, In containers holding different amts of flour
- 25. Evolution of K in Drosophila Post-radiation Control Hybrid Inbred Results suggest that K responds to an increase in genetic variation, And that it changes gradually through time in response to selection.
- 26. Assumptions of Logistic Growth Constant environment (r and K are constants) Linear response of per capita growth rate to density Equal impact of all individuals on resources Instantaneous adjustment of population growth to change in N No interactions with species other than those that are food Constantly renewed supply of food in a constant quantity
- 27. Discrete Model for Limited Growth Same assumptions, except population grows in bursts with each Generation-- built-in time lag Models of this sort show the potential influence that a time lag can have on population change.
- 28. Simple model, complex behavior R = 0.1, K = 1000
- 29. Simple model, complex behavior R = 1.9, K = 1000 Damped oscillation
- 30. Simple model, complex behavior r= 2.2, K = 1000 Limit cycle
- 31. Simple model, complex behavior r= 2.5, K = 1000 4-point cycle
- 32. Simple model, complex behavior r= 2.58, K = 1000 8-point cycle
- 33. Simple model, complex behavior r= 2.7, K = 1000 Erratic
- 34. Chaos r= 3, K = 1000
- 35. Overshoot, Crash, Extinction r= 3.000072, K = 1000
- 36. Concerns about Chaos Biological populations don’t appear to have the growth capacity to generate chaos, but this shows the potential importance of time lags. More complicated models can be even more sensitive Some systems might be completely unpredictable
- 37. Evolution of Life Histories Life history features: Rates of birth, death, population growth Patterns of reproduction and mortality Behavior associated with reproduction Efficiency of resource use, and carrying capacity Anything that affects population growth
- 38. Patterns
- 39. More patterns
- 40. Tradeoff