Title: Lecture 10 Population Age and Size Structure
1Lecture 10 Population Age and Size Structure
- I. Factors Affecting Birth and Death Rates in
Populations - A. Age
- B. Size
- C. Stage of development
- D. Gender
2Lecture 10 Population Age and Size Structure
- I. Factors Affecting Birth and Death Rates in
Populations - A. Age a young rattlesnake or elephant or
human or giant sequoia has a birth rate of zero.
Very old individuals often have a high death
rate. - B. Size
- C. Stage of development
- D. Gender
3Lecture 10 Population Age and Size Structure
- I. Factors Affecting Birth and Death Rates in
Populations - A. Age a young rattlesnake or elephant or
human or giant sequoia has a birth rate of zero.
Very old individuals often have a high death
rate. - B. Size small plants produce fewer offspring
and have higher death rates than larger
plants of the same age. - C. Stage of development
- D. Gender
4Lecture 10 Population Age and Size Structure
- I. Factors Affecting Birth and Death Rates in
Populations - A. Age a young rattlesnake or elephant or
human or giant sequoia has a birth rate of zero.
Very old individuals often have a high death
rate. - B. Size small plants produce fewer offspring
and have higher death rates than larger
plants of the same age. Small animals of many
species may also not produce as many offspring
or live as long as larger individuals of the
same age. - C. Stage of development
- D. Gender
5Lecture 10 Population Age and Size Structure
- I. Factors Affecting Birth and Death Rates in
Populations - A. Age a young rattlesnake or elephant or
human or giant sequoia has a birth rate of zero.
Very old individuals often have a high death
rate. - B. Size small plants produce fewer offspring
and have higher death rates than larger
plants of the same age. Small animals of many
species may also not produce as many offspring
or live as long as larger individuals of the
same age. - C. Stage of development most insects go
through dramatically different stages of
development, but many other organisms also have
distinct juvenile and adult stages. - D. Gender
6Lecture 10 Population Age and Size Structure
- I. Factors Affecting Birth and Death Rates in
Populations - A. Age a young rattlesnake or elephant or
human or giant sequoia has a birth rate of zero.
Very old individuals often have a high death
rate. - B. Size small plants produce fewer offspring
and have higher death rates than larger
plants of the same age. Small animals of many
species may also not produce as many offspring
or live as long as larger individuals of the
same age. - C. Stage of development most insects go
through dramatically different stages of
development, but many other organisms also have
distinct juvenile and adult stages. Juveniles of
many bird species may be as large as adults but
have very different coloration (so stage isnt
the same as size). - D. Gender
7Juvenile mallard (Anas platyrhyncos)
Male and female mallards
prairiefrontier.com
8Bald eagle juvenile (Haliaeetus leucocephalus)
Bald eagle adult (Haliaeetus leucocephalus)
Photo by Tim Knight (homepage.mac.com)
9Lecture 10 Population Age and Size Structure
- I. Factors Affecting Birth and Death Rates in
Populations - C. Stage of development most insects go
through dramatically different stages of
development, but many other organisms also have
distinct juvenile and adult stages. Juveniles of
many bird species may be as large as adults but
have very different coloration (so stage isnt
the same as size). Seeds of many plants can
live for hundreds of years without germinating
(so stage isnt the same as age). - D. Gender
10Lecture 10 Population Age and Size Structure
- I. Factors Affecting Birth and Death Rates in
Populations - C. Stage of development most insects go
through dramatically different stages of
development, but many other organisms also have
distinct juvenile and adult stages. Juveniles of
many bird species may be as large as adults but
have very different coloration (so stage isnt
the same as size). Seeds of many plants can
live for hundreds of years without germinating
(so stage isnt the same as age). - D. Gender only females give birth in animals
so most analyses of animal populations are of
females.
11Lecture 10 Population Age and Size Structure
- I. Factors Affecting Birth and Death Rates in
Populations - C. Stage of development most insects go
through dramatically different stages of
development, but many other organisms also have
distinct juvenile and adult stages. Juveniles of
many bird species may be as large as adults but
have very different coloration (so stage isnt
the same as size). Seeds of many plants can
live for hundreds of years without germinating
(so stage isnt the same as age). - D. Gender only females give birth in animals
so most analyses of animal populations are of
females. Females and males often have different
death rates also. For example, human mortality
rates are higher in men than in women in many
countries
12Lecture 10 Population Age and Size Structure
- I. Factors Affecting Birth and Death Rates in
Populations - C. Stage of development most insects go
through dramatically different stages of
development, but many other organisms also have
distinct juvenile and adult stages. Juveniles of
many bird species may be as large as adults but
have very different coloration (so stage isnt
the same as size). Seeds of many plants can
live for hundreds of years without germinating
(so stage isnt the same as age). - D. Gender only females give birth in animals
so most analyses of animal populations are of
females. Females and males often have different
death rates also. For example, human mortality
rates are higher in men than in women in many
countries but it hasnt always been that way.
13Lecture 10 Population Age and Size Structure
- II. Life Tables
- A. What is a life table?
- B. Life table parameters
- C. Classification methods for life tables
- D. Cohort vs static life tables
14Lecture 10 Population Age and Size Structure
- II. Life Tables
- A. What is a life table? Table showing the
number of individuals alive over time in a
population and the mortality rates at different
times. - B. Life table parameters
- C. Classification methods for life tables
- D. Cohort vs static life tables
15Lecture 10 Population Age and Size Structure
- II. Life Tables
- A. What is a life table? Table showing the
number of individuals alive over time in a
population and the mortality rates at different
times. - B. Life table parameters (FIGS. 1,2)
- 1.
- 2.
- 3.
- 4.
- 5.
- 6.
- C. Classification methods for life tables
- D. Cohort vs static life tables
16Lecture 10 Population Age and Size Structure
- II. Life Tables
- A. What is a life table? Table showing the
number of individuals alive over time in a
population and the mortality rates at different
times. - B. Life table parameters (FIGS. 1,2)
- 1. Time interval corresponding to age, age
class, size class, or stage of development
x - 2.
- 3.
- 4.
- 5.
- 6.
- C. Classification methods for life tables
- D. Cohort vs static life tables
17Phlox drummondii
Larry Allain_at_ USGS NWRC Plants Database
18Lecture 10 Population Age and Size Structure
- II. Life Tables
- A. What is a life table? Table showing the
number of individuals alive over time in a
population and the mortality rates at different
times. - B. Life table parameters (FIGS. 1,2)
- 1. Time interval corresponding to age, age
class, size class, or stage of development
x - 2. Number of individuals surviving to time x
ax or nx or Nx. - 3.
- 4.
- 5.
- 6.
- C. Classification methods for life tables
- D. Cohort vs static life tables
19(No Transcript)
20Western spruce budworm (Choristoneura
occidentalis)
Damage by spruce budworm
Spruce budworm adult
Entomology.umn.edu
Adult spruce budworm Climatology.umn.edu
21Lecture 10 Population Age and Size Structure
- II. Life Tables
- A. What is a life table? Table showing the
number of individuals alive over time in a
population and the mortality rates at different
times. - B. Life table parameters (FIGS. 1,2)
- 1. Time interval corresponding to age, age
class, size class, or stage of development
x - 2. Number of individuals surviving to time x
ax or nx or Nx. - 3. Survivorship, the proportion or
standardized number of individuals surviving
to time x lx. - 4.
- 5.
- 6.
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24Lecture 10 Population Age and Size Structure
- II. Life Tables
- A. What is a life table? Table showing the
number of individuals alive over time in a
population and the mortality rates at different
times. - B. Life table parameters (FIGS. 1,2)
- 1. Time interval corresponding to age, age
class, size class, or stage of development
x - 2. Number of individuals surviving to time x
ax or nx or Nx. - 3. Survivorship, the proportion or
standardized number of individuals
surviving to time x lx. - 4. Number of individuals dying between times
x and x1 dx - 5.
- 6.
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27Lecture 10 Population Age and Size Structure
- II. Life Tables
- A. What is a life table? Table showing the
number of individuals alive over time in a
population and the mortality rates at different
times. - B. Life table parameters (FIGS. 1,2)
- 1. Time interval corresponding to age, age
class, size class, or stage of development
x - 2. Number of individuals surviving to time x
ax or nx or Nx. - 3. Survivorship, the proportion or
standardized number of individuals
surviving to time x lx. - 4. Number of individuals dying between times
x and x1 dx - 5. Mortality rate (proportion of individuals
dying) between times x and x1 qx. - 6.
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30Lecture 10 Population Age and Size Structure
- II. Life Tables
- B. Life table parameters (FIGS. 1,2)
- 1. Time interval corresponding to age, age
class, size class, or stage of
development x - 2. Number of individuals surviving to time x
ax or nx or Nx. - 3. Survivorship, the proportion or
standardized number of individuals
surviving to time x lx. - 4. Number of individuals dying between times
x and x1 dx - 5. Mortality rate (proportion of individuals
dying) between times x and x1 qx. - 6. Mean life expectation (expectancy) for
individuals reaching time x ex.
31Lecture 10 Population Age and Size Structure
- II. Life Tables
- C. Classification methods for life tables (FIGS.
1,2,3,4) - 1.
- 2.
- 3.
32Lecture 10 Population Age and Size Structure
- II. Life Tables
- C. Classification methods for life tables (FIGS.
1,2,3,4) - 1. Age classes or intervals (FIGS. 1,3,4)
- 2.
- 3.
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34Red deer hind (Cervus elaphus)
Paul Hobson photo
Red deer stag
Falconergame.co.uk
35(No Transcript)
36Lecture 10 Population Age and Size Structure
- II. Life Tables
- C. Classification methods for life tables (FIGS.
1,2,3,4) - 1. Age classes or intervals (FIGS. 1,3,4)
- 2. Stage of development (FIG. 2)
- 3.
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38Lecture 10 Population Age and Size Structure
- II. Life Tables
- C. Classification methods for life tables (FIGS.
1,2,3,4) - 1. Age classes or intervals (FIGS. 1,3,4)
- 2. Stage of development (FIG. 2)
- 3. Size classes or intervals. This is often
used for plants.
39Lecture 10 Population Age and Size Structure
- II. Life Tables
- C. Classification methods for life tables (FIGS.
1,2,3,4) - 1. Age classes or intervals (FIGS. 1,3,4)
- 2. Stage of development (FIG. 2)
- 3. Size classes or intervals. This is often
used for plants. - Forest tree example 10-20 cm, 20-40 cm
40Lecture 10 Population Age and Size Structure
- II. Life Tables
- C. Classification methods for life tables (FIGS.
1,2,3,4) - 1. Age classes or intervals (FIGS. 1,3,4)
- 2. Stage of development (FIG. 2)
- 3. Size classes or intervals. This is often
used for plants. - Forest tree example 10-20 cm, 20-40 cm
- D. Cohort vs static life tables
- 1. Cohort (dynamic, age-specific) life tables
(FIGS. 1,2,3) - 2. Static (time-specific) life tables (FIG.
4)
41Lecture 10 Population Age and Size Structure
- II. Life Tables
- C. Classification methods for life tables (FIGS.
1,2,3,4) - 1. Age classes or intervals (FIGS. 1,3,4)
- 2. Stage of development (FIG. 2)
- 3. Size classes or intervals. This is often
used for plants. - Forest tree example 10-20 cm, 20-40 cm
- D. Cohort vs static life tables
- 1. Cohort (dynamic, age-specific) life tables
(FIGS. 1,2,3) - A cohort is a group of individuals of the
same age (age-mates). - 2. Static (time-specific) life tables (FIG.
4)
42Lecture 10 Population Age and Size Structure
- II. Life Tables
- C. Classification methods for life tables (FIGS.
1,2,3,4) - 1. Age classes or intervals (FIGS. 1,3,4)
- 2. Stage of development (FIG. 2)
- 3. Size classes or intervals. This is often
used for plants. - Forest tree example 10-20 cm, 20-40 cm
- D. Cohort vs static life tables
- 1. Cohort (dynamic, age-specific) life tables
(FIGS. 1,2,3) - A cohort is a group of individuals of the
same age (age-mates). To develop a
cohort life table, you follow all individuals of
a cohort from birth until every individual
has died. - 2. Static (time-specific) life tables (FIG.
4)
43Lecture 10 Population Age and Size Structure
- II. Life Tables
- D. Cohort vs static life tables
- 1. Cohort (dynamic, age-specific) life tables
(FIGS. 1,2,3) - A cohort is a group of individuals of the
same age (age-mates). To develop a
cohort life table, you follow all individuals of
a cohort from birth until every individual
has died. The most useful and most accurate
life table but . . . - 2. Static (time-specific) life tables (FIG.
4)
44Lecture 10 Population Age and Size Structure
- II. Life Tables
- D. Cohort vs static life tables
- 1. Cohort (dynamic, age-specific) life tables
(FIGS. 1,2,3) - A cohort is a group of individuals of the
same age (age-mates). To develop a
cohort life table, you follow all individuals of
a cohort from birth until every individual
has died. The most useful and most accurate
life table but it may be difficult to locate
all individuals at birth and follow them until
the last one has died. - 2. Static (time-specific) life tables (FIG.
4)
45Lecture 10 Population Age and Size Structure
- II. Life Tables
- D. Cohort vs static life tables
- 1. Cohort (dynamic, age-specific) life tables
(FIGS. 1,2,3) - A cohort is a group of individuals of the
same age (age-mates). To develop a
cohort life table, you follow all individuals of
a cohort from birth until every individual
has died. The most useful and most accurate
life table but it may be difficult to locate
all individuals at birth and follow them until
the last one has died. Its not good for
long-lived species! - 2. Static (time-specific) life tables (FIG.
4)
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49Lecture 10 Population Age and Size Structure
- II. Life Tables
- D. Cohort vs static life tables
- 1. Cohort (dynamic, age-specific) life tables
(FIGS. 1,2,3) - A cohort is a group of individuals of the
same age (age-mates). To develop a
cohort life table, you follow all individuals of
a cohort from birth until every individual
has died. The most useful and most accurate
life table but it may be difficult to locate
all individuals at birth and follow them until
the last one has died. Its not good for
long-lived species! - 2. Static (time-specific) life tables (FIG.
4) - To develop a static life table, you first
estimate the age of each individual in a
population at a particular time.
50Lecture 10 Population Age and Size Structure
- II. Life Tables
- D. Cohort vs static life tables
- 2. Static (time-specific) life tables
(FIG. 4) - To develop a static life table, you first
estimate the age of each individual in a
population at a particular time. Assuming that b
and d have remained constant since the
oldest individual was born, you work back
from the oldest individuals to the youngest
to estimate how many were born in each year.
51(No Transcript)
52Lecture 10 Population Age and Size Structure
- II. Life Tables
- D. Cohort vs static life tables
- 2. Static (time-specific) life tables (FIG.
4) - To develop a static life table, you first
estimate the age of each individual in a
population at a particular time. Assuming that b
and d have remained constant since the
oldest individual was born, you work back
from the oldest individuals to the youngest
to estimate how many were born in each year.
Sometimes these data are smoothed to
eliminate oddities as we see for ages 6
and 7 in FIG. 4.
53(No Transcript)
54Lecture 10 Population Age and Size Structure
- II. Life Tables
- D. Cohort vs static life tables
- 2. Static (time-specific) life tables (FIG.
4) - To develop a static life table, you first
estimate the age of each individual in a
population at a particular time. Assuming that b
and d have remained constant since the
oldest individual was born, you work back
from the oldest individuals to the youngest
to estimate how many were born in each year.
Sometimes these data are smoothed to
eliminate oddities as we see for ages 6
and 7 in FIG. 4. Static life tables are used for
long-lived organisms like trees,
humans, and other large mammals.
55Lecture 10 Population Age and Size Structure
- III. Survivorship Curves
- A. How to develop survivorship curves
- B. Three standard survivorship curves (FIG. 5)
- C. Examples of survivorship curves in nature
(FIGS. 6,7,8)
56Lecture 10 Population Age and Size Structure
- III. Survivorship Curves
- A. How to develop survivorship curves
- Plot the logarithm of survivorship (log lx) on
Y-axis and age, size, or stage on
X-axis. Usually use natural logs but can use any
base. - B. Three standard survivorship curves (FIG. 5)
- C. Examples of survivorship curves in nature
(FIGS. 6,7,8)
57Lecture 10 Population Age and Size Structure
- III. Survivorship Curves
- A. How to develop survivorship curves
- Plot the logarithm of survivorship (log lx) on
Y-axis and age, size, or stage on X-axis.
Usually use natural logs but can use any base.
These curves show the proportion of individuals
dying (i.e. the mortality rate) at each age,
size, or stage. - B. Three standard survivorship curves (FIG. 5)
- C. Examples of survivorship curves in nature
(FIGS. 6,7,8)
58(No Transcript)
59Lecture 10 Population Age and Size Structure
- III. Survivorship Curves
- A. How to develop survivorship curves
- Plot the logarithm of survivorship (log lx) on
Y-axis and age, size, or stage on X-axis.
Usually use natural logs but can use any base.
These curves show the proportion of individuals
dying (i.e. the mortality rate) at each age,
size, or stage. - B. Three standard survivorship curves (FIG. 5)
- C. Examples of survivorship curves in nature
(FIGS. 6,7,8)
60Lecture 10 Population Age and Size Structure
- III. Survivorship Curves
- A. How to develop survivorship curves
- Plot the logarithm of survivorship (log lx) on
Y-axis and age, size, or stage on X-axis.
Usually use natural logs but can use any base.
These curves show the proportion of individuals
dying (i.e. the mortality rate) at each age,
size, or stage. - B. Three standard survivorship curves (FIG. 5)
- Developed by Pearl--often called Deevey
curves. These show general patterns of
mortality in natural populations. - C. Examples of survivorship curves in nature
(FIGS. 6,7,8)
61(No Transcript)
62Lecture 10 Population Age and Size Structure
- III. Survivorship Curves
- B. Three standard survivorship curves (FIG. 5)
- Developed by Pearl--often called Deevey
curves. These show general patterns of
mortality in natural populations. In Type I
curves, most mortality occurs late in life.
Typical of humans and other large organisms that
have few offspring and give much parental care. - C. Examples of survivorship curves in nature
(FIGS. 6,7,8)
63(No Transcript)
64Lecture 10 Population Age and Size Structure
- III. Survivorship Curves
- B. Three standard survivorship curves (FIG. 5)
- Developed by Pearl--often called Deevey
curves. These show general patterns of
mortality in natural populations. In Type I
curves, most mortality occurs late in life.
Typical of humans and other large organisms that
have few offspring and give much parental care.
Type II curves have fairly constant mortality
rate throughout life. Typical of many bird
species and other organisms with intermediate
number of offspring and parental care. - C. Examples of survivorship curves in nature
(FIGS. 6,7,8)
65(No Transcript)
66Lecture 10 Population Age and Size Structure
- III. Survivorship Curves
- B. Three standard survivorship curves (FIG. 5)
- Developed by Pearl--often called Deevey
curves. These show general patterns of
mortality in natural populations. In Type I
curves, most mortality occurs late in life.
Typical of humans and other large organisms that
have few offspring and give much parental care.
Type II curves have fairly constant mortality
rate throughout life. Typical of many bird
species and other organisms with intermediate
number of offspring and parental care. In Type
III curves, most mortality occurs early in life.
Typical of insects, marine invertebrates,
plants, and other organisms that produce many
offspring but few survive because there is
little parental care for individual offspring. - C. Examples of survivorship curves in nature
(FIGS. 6,7,8)
67(No Transcript)
68Lecture 10 Population Age and Size Structure
- III. Survivorship Curves
- C. Examples of survivorship curves in nature
(FIGS. 6,7,8)
69(No Transcript)
70Lecture 10 Population Age and Size Structure
- III. Survivorship Curves
- C. Examples of survivorship curves in nature
(FIGS. 6,7,8) - Dall sheep in FIG. 6 have Type I survivorship.
71(No Transcript)
72Lecture 10 Population Age and Size Structure
- III. Survivorship Curves
- C. Examples of survivorship curves in nature
(FIGS. 6,7,8) - Dall sheep in FIG. 6 have Type I survivorship.
- Various birds in FIG. 7 have Type II
survivorship.
73(No Transcript)
74Lecture 10 Population Age and Size Structure
- III. Survivorship Curves
- C. Examples of survivorship curves in nature
(FIGS. 6,7,8) - Dall sheep in FIG. 6 have Type I survivorship.
- Various birds in FIG. 7 have Type II
survivorship. - The tropical palms in FIG. 8 have Type III
survivorship.
75Lecture 10 Population Age and Size Structure
- IV. Fecundity Schedules
- A. What is a fecundity schedule?
- B. Fecundity schedule parameters
- C. What does net reproductive rate represent?
- D. Examples
76Lecture 10 Population Age and Size Structure
- IV. Fecundity Schedules
- A. What is a fecundity schedule? A table
showing the number of offspring produced at each
age (or size or stage) and also showing the
survival of the parent. - B. Fecundity schedule parameters
- C. What does net reproductive rate represent?
- D. Examples
77(No Transcript)
78Lecture 10 Population Age and Size Structure
- IV. Fecundity Schedules
- A. What is a fecundity schedule? A table
showing the number of offspring produced at each
age (or size or stage) and also showing the
survival of the parent. - B. Fecundity schedule parameters
- 1. Number of offspring produced per
individual from age (or time) x to x1
mx or bx.
79(No Transcript)
80Lecture 10 Population Age and Size Structure
- IV. Fecundity Schedules
- A. What is a fecundity schedule? A table
showing the number of offspring produced at each
age (or size or stage) and also showing the
survival of the parent. - B. Fecundity schedule parameters
- 1. Number of offspring produced per
individual from age (or time) x to x1
mx or bx. - 2. Number of offspring produced by all
individuals from age (or time) x to x1
Fx.
81(No Transcript)
82Lecture 10 Population Age and Size Structure
- IV. Fecundity Schedules
- A. What is a fecundity schedule? A table
showing the number of offspring produced at each
age (or size or stage) and also showing the
survival of the parent. - B. Fecundity schedule parameters
- 1. Number of offspring produced per
individual from age (or time) x to x1
mx or bx. - 2. Number of offspring produced by all
individuals from age (or time) x to x1
Fx. - 3. Net reproductive rate R0 sum of
products of lx and mx values.
83(No Transcript)
84Lecture 10 Population Age and Size Structure
- IV. Fecundity Schedules
- B. Fecundity schedule parameters
- 1. Number of offspring produced per
individual from age (or time) x to x1
mx or bx. - 2. Number of offspring produced by all
individuals from age (or time) x to x1
Fx. - 3. Net reproductive rate R0 sum of
products of lx and mx values. - C. What does the net reproductive rate represent?
85Lecture 10 Population Age and Size Structure
- IV. Fecundity Schedules
- B. Fecundity schedule parameters
- 1. Number of offspring produced per
individual from age (or time) x to x1
mx or bx. - 2. Number of offspring produced by all
individuals from age (or time) x to x1
Fx. - 3. Net reproductive rate R0 sum of
products of lx and mx values. - C. What does the net reproductive rate
represent? R0 measures the growth (or
decline) in a population from one generation to
the next. Its similar to ? but ? measures
growth in the population from one year to the
next.
86Lecture 10 Population Age and Size Structure
- IV. Fecundity Schedules
- C. What does the net reproductive rate
represent? R0 measures the growth (or
decline) in a population from one generation to
the next. Its similar to ? but ? measures
growth in the population from one year to
the next. - D. Examples
- 1. Phlox (FIG. 9)
- 2. Red deer (hinds)(FIG. 10)
- 3. Field grasshopper (FIG. 11)
- 4. Human females (FIG. 12)
87(No Transcript)
88Lecture 10 Population Age and Size Structure
- IV. Fecundity Schedules
- C. What does the net reproductive rate
represent? R0 measures the growth (or
decline) in a population from one generation to
the next. Its similar to ? but ? measures
growth in the population from one year to
the next. - D. Examples
- 1. Phlox (FIG. 9). R0 2.4177 so each
individual in the previous generation
replaces itself with more than 2 individuals in
the next generation. The population will
increase. - 2. Red deer (hinds)(FIG. 10)
- 3. Field grasshopper (FIG. 11)
- 4. Human females (FIG. 12)
89(No Transcript)
90Lecture 10 Population Age and Size Structure
- IV. Fecundity Schedules
- D. Examples
- 1. Phlox (FIG. 9). R0 2.4177 so each
individual in the previous generation
replaces itself with more than 2 individuals in
the next generation. The population will
increase. - 2. Red deer (hinds)(FIG. 10). R0 1.316 so
the population should increase. - 3. Field grasshopper (FIG. 11)
- 4. Human females (FIG. 12)
91(No Transcript)
92Lecture 10 Population Age and Size Structure
- IV. Fecundity Schedules
- D. Examples
- 1. Phlox (FIG. 9). R0 2.4177 so each
individual in the previous generation
replaces itself with more than 2 individuals in
the next generation. The population will
increase. - 2. Red deer (hinds)(FIG. 10). R0 1.316 so
the population should increase. - 3. Field grasshopper (FIG. 11). R0 0.51 so
the population will decline. - 4. Human females (FIG. 12)
93(No Transcript)
94Lecture 10 Population Age and Size Structure
- IV. Fecundity Schedules
- D. Examples
- 1. Phlox (FIG. 9). R0 2.4177 so each
individual in the previous generation
replaces itself with about 2.4 individuals in the
next generation. The population will
increase. - 2. Red deer (hinds)(FIG. 10). R0 1.316 so
the population should increase. - 3. Field grasshopper (FIG. 11). R0 0.51 so
the population will decline. - 4. Human females (FIG. 12). R0 1.0061 so
the population of women in the U.S. is
increasing at a rate of 0.61.
95Lecture 10 Population Age and Size Structure
- IV. Fecundity Schedules
- D. Examples
- 1. Phlox (FIG. 9). R0 2.4177 so each
individual in the previous generation
replaces itself with about 2.4 individuals in the
next generation. The population will
increase. - 2. Red deer (hinds)(FIG. 10). R0 1.316 so
the population should increase. - 3. Field grasshopper (FIG. 11). R0 0.51 so
the population will decline. - 4. Human females (FIG. 12). R0 1.0061 so
the population of women in the U.S. is
increasing at a rate of 0.61. That is
currently the approximate growth rate in the
U.S.
96Lecture 10 Population Age and Size Structure
- V. Life Cycle Graphs and Transition Matrix
Models - A. Age-classified populations (Leslie matrix
models)(FIG. 13A) - B. Size-classified populations (FIG. 13B)
- C. Stage-classified populations (FIG. 14)
- D. Assumptions of matrix models
- E. Projecting population growth using matrix
models (FIGS. 15,16,17) - F. Including density-dependence to make matrix
models more realistic.
97Lecture 10 Population Age and Size Structure
- V. Life Cycle Graphs and Transition Matrix
Models - A. Age-classified populations (Leslie matrix
models)(FIG. 13A) - 1. Life-cycle graphs
- 2. Transition matrix models
98Lecture 10 Population Age and Size Structure
- V. Life Cycle Graphs and Transition Matrix
Models - A. Age-classified populations (Leslie matrix
models)(FIG. 13A) - 1. Life-cycle graphs - show all age classes,
the probability of surviving from one age
to the next (P), and the fecundity at each
age (F). - 2. Transition matrix models
99(No Transcript)
100Lecture 10 Population Age and Size Structure
- V. Life Cycle Graphs and Transition Matrix
Models - A. Age-classified populations (Leslie matrix
models)(FIG. 13A) - 1. Life-cycle graphs - show all age classes,
the probability of surviving from one
age to the next (P), and the fecundity at
each age (F). - 2. Transition matrix models
101Lecture 10 Population Age and Size Structure
- V. Life Cycle Graphs and Transition Matrix
Models - A. Age-classified populations (Leslie matrix
models)(FIG. 13A) - 1. Life-cycle graphs - show all age classes,
the probability of surviving from one age
to the next (P), and the fecundity at each
age (F). - 2. Transition matrix models. Matrix Aa
contains the same information as the
life-cycle graph. Columns indicate age
classes at the present (time t) and rows indicate
the same age classes at time t 1.
102(No Transcript)
103Lecture 10 Population Age and Size Structure
- V. Life Cycle Graphs and Transition Matrix
Models - A. Age-classified populations (Leslie matrix
models)(FIG. 13A) - 1. Life-cycle graphs - show all age classes,
the probability of surviving from one age
to the next (P), and the fecundity at each
age (F). - 2. Transition matrix models. Matrix Aa
contains the same information as the
life-cycle graph. Columns indicate age
classes at the present (time t) and rows indicate
the same age classes at time t 1. - B. Size-classified populations (FIG. 13B)
- 1. Life-cycle graphs
- 2. Transition matrix models
104Lecture 10 Population Age and Size Structure
- V. Life Cycle Graphs and Transition Matrix
Models - A. Age-classified populations (Leslie matrix
models)(FIG. 13A) - 1. Life-cycle graphs - show all age classes,
the probability of surviving from one age
to the next (P), and the fecundity at each
age (F). - 2. Transition matrix models. Matrix Aa
contains the same information as
the life-cycle graph. Columns indicate age
classes at the present (time t) and rows
indicate the same age classes at time t
1. - B. Size-classified populations (FIG. 13B)
- 1. Life-cycle graphs - show all size classes,
the probability of surviving but remaining
in the same size class (P), the
probability of growing into the next size class
(G), and fecundity of each size class
(F). - 2. Transition matrix models
105(No Transcript)
106Lecture 10 Population Age and Size Structure
- V. Life Cycle Graphs and Transition Matrix
Models - B. Size-classified populations (FIG. 13B)
- 1. Life-cycle graphs - show all size classes,
the probability of surviving but remaining
in the same size class (P), the
probability of growing into the next size class
(G), and fecundity of each size class
(F). - 2. Transition matrix models. Contain the
same P, G, and F values as the life-cycle
graphs.
107(No Transcript)
108Lecture 10 Population Age and Size Structure
- V. Life Cycle Graphs and Transition Matrix
Models - B. Size-classified populations (FIG. 13B)
- 1. Life-cycle graphs - show all size classes,
the probability of surviving but remaining
in the same size class (P), the
probability of growing into the next size class
(G), and fecundity of each size class
(F). - 2. Transition matrix models. Contain the
same P, G, and F values as the life-cycle
graphs. Notice that the age-classified matrix
has all zeroes on the diagonal, whereas the
size-classified matrix may have values
greater than zero.
109(No Transcript)
110Lecture 10 Population Age and Size Structure
- V. Life Cycle Graphs and Transition Matrix
Models - B. Size-classified populations (FIG. 13B)
- 2. Transition matrix models. Contain the
same P, G, and F values as the life-cycle
graphs, with arrows indicating probability of
staying in the same size class (P) or of
growing (G) and the fecundity (F). Notice
that the age-classified matrix has all zeroes
on the diagonal, whereas the size-classified
matrix may have values greater than zero. - C. Stage-classified populations (FIG. 14)
- 1. Insect stages of development (FIG. 14a)
- 2. Stages of development in a tree population
(FIG. 14b) - 3. Coral life stages with sexual and asexual
reproduction (FIG. 14c)
111Lecture 10 Population Age and Size Structure
- V. Life Cycle Graphs and Transition Matrix
Models - C. Stage-classified populations (FIG. 14)
- 1. Insect stages of development (FIG. 14a)
- 2. Stages of development in a tree population
(FIG. 14b) - 3. Coral life stages with sexual and asexual
reproduction (FIG. 14c)
112(No Transcript)
113Lecture 10 Population Age and Size Structure
- V. Life Cycle Graphs and Transition Matrix
Models - C. Stage-classified populations (FIG. 14)
- 1. Insect stages of development (FIG. 14a)
- Each circle now represents a different
stage of development. Notice the different
notation for P and F. - 2. Stages of development in a tree population
(FIG. 14b) - 3. Coral life stages with sexual and asexual
reproduction (FIG. 14c)
114(No Transcript)
115Lecture 10 Population Age and Size Structure
- V. Life Cycle Graphs and Transition Matrix
Models - C. Stage-classified populations (FIG. 14)
- 1. Insect stages of development (FIG. 14a)
- Each circle now represents a different
stage of development. Notice the different
notation for P and F. - 2. Stages of development in a tree population
(FIG. 14b) -
- 3. Coral life stages with sexual and asexual
reproduction (FIG. 14c)
116(No Transcript)
117Lecture 10 Population Age and Size Structure
- V. Life Cycle Graphs and Transition Matrix
Models - C. Stage-classified populations (FIG. 14)
- 1. Insect stages of development (FIG. 14a)
- Each circle now represents a different
stage of development. Notice the different
notation for P and F. - 2. Stages of development in a tree population
(FIG. 14b) - Numbered stages could be seed, seedling,
sapling, mature tree, and senescent tree
(past its prime). - 3. Coral life stages with sexual and asexual
reproduction (FIG. 14c)
118(No Transcript)
119Lecture 10 Population Age and Size Structure
- V. Life Cycle Graphs and Transition Matrix
Models - C. Stage-classified populations (FIG. 14)
- 1. Insect stages of development (FIG. 14a)
- Each circle now represents a different
stage of development. Notice the different
notation for P and F. - 2. Stages of development in a tree population
(FIG. 14b) - Numbered stages could be seed, seedling,
sapling, mature tree, and senescent tree
(past its prime). - 3. Coral life stages with sexual and asexual
reproduction (FIG. 14c) -
120(No Transcript)
121Lecture 10 Population Age and Size Structure
- V. Life Cycle Graphs and Transition Matrix
Models - C. Stage-classified populations (FIG. 14)
- 1. Insect stages of development (FIG. 14a)
- Each circle now represents a different
stage of development. Notice the
different notation for P and F. - 2. Stages of development in a tree population
(FIG. 14b) - Numbered stages could be seed, seedling,
sapling, mature tree, and senescent tree
(past its prime). - 3. Coral life stages with sexual and asexual
reproduction (FIG. 14c) - The coral life cycle is more complicated.
It can grow slowly or quickly and it can
reproduce sexually (F) or asexually (P) by
fragmenting into smaller pieces.
122(No Transcript)
123Lecture 10 Population Age and Size Structure
- V. Life Cycle Graphs and Transition Matrix
Models - C. Stage-classified populations (FIG. 14)
- 3. Coral life stages with sexual and asexual
reproduction (FIG. 14c) - The coral life cycle is more complicated.
It can grow slowly or quickly and it can
reproduce sexually (F) or asexually (P) by
fragmenting into smaller pieces. - Remember that stage-classified and
size-classified matrices can both have positive
values along the diagonal. Age-classified
matrices can only have zeroes on the diagonal
(because you cant stay the same age from one
year to the next). Age-classified matrices are
often called Leslie matrices in honor of Patrick
Leslie. Also remember that fecundity (number of
offspring) is shown on the first row of the
matrix.
124Lecture 10 Population Age and Size Structure
- V. Life Cycle Graphs and Transition Matrix
Models - Remember that stage-classified and
size-classified matrices can both have positive
values along the diagonal. Age-classified
matrices can only have zeroes on the diagonal
(because you cant stay the same age from one
year to the next). Age-classified matrices are
often called Leslie matrices in honor of Patrick
Leslie. Also remember that fecundity (number of
offspring) is shown on the first row of the
matrix. - D. Assumptions of transition matrix models
- 1. Stationarity
- 2. Markov property
125Lecture 10 Population Age and Size Structure
- V. Life Cycle Graphs and Transition Matrix
Models - D. Assumptions of transition matrix models
- 1. Stationarity - P, G, and F values dont
change over time. No stochastic effects of
weather or disturbance and no resource
limitation. - 2. Markov property
126Lecture 10 Population Age and Size Structure
- V. Life Cycle Graphs and Transition Matrix
Models - D. Assumptions of transition matrix models
- 1. Stationarity - P, G, and F values dont
change over time. No stochastic effects of
weather or disturbance and no resource
limitation. - 2. Markov property - P, G, and F values only
depend on the current age, size, or stage of
development and not on the past history of
the individual. In the coral example, the
probability of a medium-sized individual
becoming a large individual doesnt depend
on how long it has been in the medium-sized
stage or how it got to that stage.
127(No Transcript)
128Lecture 10 Population Age and Size Structure
- V. Life Cycle Graphs and Transition Matrix
Models - D. Assumptions of transition matrix models
- 2. Markov property - P, G, and F values only
depend on the current age, size, or stage of
development and not on the past history of
the individual. In the coral example, the
probability of a medium-sized individual
becoming a large individual dont depend on
how long it has been in the medium-sized stage or
how it got to that stage. - E. Projecting population growth using matrix
models (FIGS. 15,16,17) -
129Lecture 10 Population Age and Size Structure
- V. Life Cycle Graphs and Transition Matrix
Models - D. Assumptions of transition matrix models
- 2. Markov property - P, G, and F values only
depend on the current age, size, or stage of
development and not on the past history of the
individual. In the coral example, the
probability of a medium-sized individual
becoming a large individual dont depend on
how long it has been in the medium-sized stage or
how it got to that stage. - E. Projecting population growth using matrix
models (FIGS. 15,16,17) - We use matrix multiplication to project
population growth into the future. We
multiply the matrix by an initial population
vector that shows how many individuals are in
each age or size class or stage of
development.
130(No Transcript)
131Lecture 10 Population Age and Size Structure
- V. Life Cycle Graphs and Transition Matrix
Models - E. Projecting population growth using matrix
models (FIGS. 15,16,17) - We use matrix multiplication to project
population growth into the future. We multiply
the matrix by an initial population vector that
shows how many individuals are in each age or
size class or stage of development. By repeated
multiplication, we can predict the growth rate
(?), future N, and the expected proportion of
individuals in each age or size class or stage
of development (see handout).
132(No Transcript)
133Lecture 10 Population Age and Size Structure
- V. Life Cycle Graphs and Transition Matrix
Models - E. Projecting population growth using matrix
models (FIGS. 15,16,17) - We use matrix multiplication to project
population growth into the future. We multiply
the matrix by an initial population vector that
shows how many individuals are in each age or
size class or stage of development. By repeated
multiplication, we can predict the growth rate
(?), future N, and the expected proportion of
individuals in each age or size class or stage
of development (see handout). We can also
determine what part of the life cycle is most
important for maintaining the population at a
reasonable size and what type of conservation
efforts might be most effective.
134Lecture 10 Population Age and Size Structure
- V. Life Cycle Graphs and Transition Matrix
Models - E. Projecting population growth using matrix
models (FIGS. 15,16,17) - Properties of matrix models
- 1. The proportion of individuals in each age or
size class or stage of development eventually
stabilizes (FIG. 15). -
135(No Transcript)
136Lecture 10 Population Age and Size Structure
- V. Life Cycle Graphs and Transition Matrix
Models - E. Projecting population growth using matrix
models (FIGS. 15,16,17) - Properties of matrix models
- 1. The proportion of individuals in each age or
size class or stage of development eventually
stabilizes (FIG. 15). - 2. The stable population growth rate, ?,
depends only on the matrix, not on the
starting population (FIG. 16). -
137(No Transcript)
138Lecture 10 Population Age and Size Structure
- V. Life Cycle Graphs and Transition Matrix
Models - E. Projecting population growth using matrix
models (FIGS. 15, 16, 17) - Properties of matrix models
- 1. The proportion of individuals in each age or
size class or stage of development eventually
stabilizes (FIG. 15). - 2. The stable population growth rate, ?,
depends only on the matrix, not on the
starting population (FIG. 16). - 3. If a model has only one positive fecundity
value, the population will cycle (FIG. 17).
139(No Transcript)
140Lecture 10 Population Age and Size Structure
- V. Life Cycle Graphs and Transition Matrix
Models - F. Including density-dependence to make matrix
models more realistic (FIGS. 18, 19, 20). -
141Lecture 10 Population Age and Size Structure
- V. Life Cycle Graphs and Transition Matrix
Models - F. Including density-dependence to make matrix
models more realistic (FIGS. 18, 19, 20).
Instead of having constant probabilities and
fecundities in the matrix, you can use functions
that depend on population density to account for
resource limitations. This makes the
models similar to logistic models and much more
realistic. -
142(No Transcript)
143Lecture 10 Population Age and Size Structure
- VI. Application of Matrix Population Models in
Conservation and Management - A. Three important applications
- B. Procedure
- C. Exam