population dynamics

POPULATION DYNAMICS

Module 5

LESSON 1ORGANISM AND POPULATION

▪Organism▪ Is a single, living individual, either plant or

animal.

▪Population▪ Is a collective group of organisms of the

same species living in the same place at thesame time.


▪ CHARACTERISTICS OF POPULATION1. Size – pertains to the number of individuals in a population.▪ The size of a population can be stated as:

Example:▪ Kind – Homo Sapiens – May 1, 2000 – 76,504,077 – Philippines▪ The recorded population of people in the Philippines according to

National Statistics Office on May 1, 2000 is 76,504,077.

Kind –What species –Time –What date/month/year Place –Where located – Number – How many


▪ FACTORS THAT CONTRIBUTE TO THE SIZEOF POPULATION:▪ Natality – the number of species that are born

▪ Mortality – the number of species that die

▪ Immigration – the number of species thatentered the land

▪ Migration – the number of species that leavethe land


▪CHARACTERISTICS OF POPULATION2. Density – is the number of individual

per unit in space. The population densityincreases when the factors are favorableto the population and decreases whenthey are unfavorable.

3. Distribution – the arrangement of theindividuals of a population with aparticular space.


▪ THREE PATTERNS OF DISTRIBUTION1. Random DistributionThere is no specific order in random

distribution, the organism spreadsthroughout the area without an overallpattern.


▪ THREE PATTERNS OF DISTRIBUTION2. Uniform DistributionThe organism are evenly distributed over

an area.


▪ THREE PATTERNS OF DISTRIBUTION3. Clumped DistributionThe organism are concentrated in one

area.

LESSON 2DYANAMICS OF POPULATION GROWTH

▪ Populations have a birth rate, death rate and growth rate.▪ Birth Rate - the number of young produced per unit of population

per unit of time.

▪ Death Rate - the number of deaths per unit of time.

▪ The major agent of population growth is births.

▪ The major agent of population loss is deaths.

▪ 𝐵𝑖𝑟𝑡ℎ > 𝐷𝑒𝑎𝑡ℎ𝑠 = 𝑃𝑜𝑝𝑢𝑙𝑎𝑡𝑖𝑜𝑛 𝐼𝑛𝑐𝑟𝑒𝑎𝑠𝑒𝑠

▪ 𝐷𝑒𝑎𝑡ℎ𝑠 > 𝐵𝑖𝑟𝑡ℎ𝑠 = 𝑃𝑜𝑝𝑢𝑙𝑎𝑡𝑖𝑜𝑛 𝐷𝑒𝑐𝑟𝑒𝑎𝑠𝑒𝑠

▪ Zero Population Growth – when birth is equals to death in a given population.


▪BIOTIC POTENTIAL▪The biotic potential of an organism is

the number of offspring that couldtheoretically exists if all offspringsurvived and produced young.


▪CARRYING CAPACITY▪The number of individuals in a

particular population that theenvironment can support over anindefinite periods of time in terms offood, space, and shelter.


▪POPULATION OSCILLATIONSAND INTERRUPTIVE GROWTH▪Crash or Dieback – the growth curve

becomes negative rather thanpositive, and the populationdecreases as fast, or faster, than itgrew.


▪POPULATION OSCILLATIONSAND INTERRUPTIVE GROWTH▪Overshoot – the extent to which a

population exceeds capacity of itsenvironment .


▪POPULATION OSCILLATIONSAND INTERRUPTIVE GROWTH▪ Irruptive or Malthisian Growth –

named after Thomas Malthus, whoconcluded that human populationstend to grow until they exhaust theirresources and become subject tofamine, disease or war.


Po

pu

lati

on

Siz

e

Time

POPULATION OSCILLATION

Die Back

Carrying Capacity of the

Environment

Overshoot


▪ENVIRONMENTAL RESISTANCE▪ Is the collection of factors that

reduce the growth rate of apopulation.▪The result of an increase in

mortality and decrease in natality.


▪ J CurveRepresents the growth without restraint.

▪S Curve (Sigmoidal Curve)Represents the logistic growth.

▪The area between the curve is thecumulative effects of environmentalresistance.

LESSON 3FACTORS AFFECTING POPULATION SIZE

▪NatalityIs the production of new individuals by

birth, hatching, germination and cloningand it is the main of addition to mostbiological populations.


▪FecundityIs the physical ability to reproduce while

fertility is a measure of the actual numberof offspring produced.


▪Mortality (Death Rate)Is determined by dividing the number of

organisms that die in a certain time periodby the number alive at the beginning of theperiod.


▪SurvivorshipThe death schedule of the organisms taken

as a sample for study.


▪DEWEY’S 3 TYPES OF SURVIVORSHIP CURVES1. Type I (Convex)When an individual tend to live out their

physical life span and when there is a highdegree of survival throughout life followed byheavy morality at the end of the species lifespan.Typical to human and other mammals and

some plants.


▪DEWEY’S 3 TYPES OF SURVIVORSHIP CURVES2. Type II (Linear)If mortality are constant at all stages.Is common characteristics of the adult stages of

birds, rodents, reptiles and perennial plans.


▪DEWEY’S 3 TYPES OF SURVIVORSHIP CURVES2. Type III (Concave)If mortality is extremely high in early life as an

oyster, fish, many vertebrates and some plants.


Type I Population- There is high survivorship until

some age and high mortality

Type II Population- Shows a fairly constant death

rate at all ages

Type III Population- There is low survivorship early in life


▪Life TableIs created to summarize the age specific

pattern of birth and death of a particularpopulation in a particular environment.

▪Cohort or Dynamic Life TableIt records the fate of a group of individual,

all born in a single period of time, from birthto death.


Age Interval (Days) Survivorship (number of

surviving at start of interval)

Number Dying During Interval

Death Rate per Individual During

Interval

*Birth Rate* (number of seeds

produced per individual) During

Interval

0-63 996 328 0.329 0

66-124 668 373 0.558 0

124-184 295 105 0.356 0

184-215 190 104 0.074 0

215-264 176 4 0.023 0

264-278 172 5 0.029 0

278-292 167 8 0.048 0

292-306 159 5 0.031 0.33

306-320 154 7 0.045 3.13

320-334 147 42 0.286 5.42

334-348 105 83 0.790 9.26

362 0 0 0 0

Total 996

Life table for a Cohort of Annual

Plants (PhilloxDrummondill)


▪EmigrationIs the movement of numbers out of a

population,Is the second major factor that reduces

population size.

LESSON 4FACTORS THAT REGULATE POPULATION GROWTH

▪DENSITY DEPENDENT FACTORS▪Density-dependent mechanism tend to

reduce population size by decreasingnatality or increasing mortality as thepopulation size increases.


▪ he An African fish eagle flies offfrom the surface of a river, clutching acatfish. These birds of prey are usuallyfound in pairs, perched in trees andscanning the water for fish andsometimes for the eggs of youngwater birds and reptiles, or othersmall animals. Its rich brown andblack wings, white head and bib andyellow beak can be seen clearly.


▪DENSITY INDEPENDENT FACTORSIn general, the factors that affect natality

and mortality independently of populationdensity tend to be abiotic components ofthe ecosystem.Often weather or climate are among the

most important of these factors.


▪DENSITY INDEPENDENT FACTORSExample: The decline in the population inOrmoc City caused by deforestation, floods,volcanic activities can destroy the entirepopulation. By building damps, breakwater,resorts and expansions city, we can changemany habitats. Human beings haveexterminated the whole population of manyorganism.

LESSON 5PHILIPPINE POPULATION

▪The population of the Philippineshas been steadily growing for manyyears. In 2014, it is the 12th mostpopulated country in the world.


▪ The 2010 Census of Population andHousing Reveals the PhilippinePopulation at 92.34 Million▪ Reference Number:

▪ 2012-027▪ Release Date:

▪ Wednesday, April 4, 2012


▪ The country's population increased by15.83 million▪ The total population of the Philippines as

of May 1, 2010 is 92,337,852 based on the2010 Census of Population and Housing.The census counts up to the barangaylevel were made official with the signingby President Benigno S. Aquino III ofProclamation No. 362 on March 30, 2012.


▪ The 2010 population is higher by 15.83million compared to the 2000 population of76.51 million. In 1990, the total populationwas 60.70 million.

Census YearCensus

Reference DatePhilippine Population

(in million)

2010 May 1, 2010 92.34

2000 May 1, 2000 76.51

1990 May 1, 1990 60.70


▪ Population grew by 1.90 percent annually▪ The Philippine population increased at the rate of 1.90 percent annually, on the

average, during the period 2000-2010. This means that there were two persons added per year for every 100 persons in the population.

Reference PeriodAverage Annual Growth Rate

for the Philippines(in percent)

2000-2010 1.90

1990-2000 2.34


▪ CALABARZON, NCR, and Central Luzoncomprise more than one-third of the totalpopulation▪ Among the 17 regions, CALABARZON (Region

IVA) had the largest population with 12.61 million,followed by the National Capital Region (NCR)with 11.86 million and Central Luzon (Region III)with 10.14 million. The population of these threeregions together comprised more than one-third(37.47 percent) of the Philippine population.


▪ Cavite topped in population size

▪ Among the provinces, Cavite had the largest population with 3.09 million. Bulacan had the second largest with 2.92 million and Pangasinan had the third largest with 2.78 million.

▪ Six other provinces surpassed the two million mark: Laguna (2.67 million); Cebu, excluding its three highly urbanized cities Cebu City, Lapu-LapuCity, and Mandaue City (2.62 million); Rizal (2.48 million); Negros Occidental, excluding Bacolod City (2.40 million); Batangas (2.38 million) and Pampanga, excluding Angeles City (2.01 million).

▪ The provinces with a population of less than 100,000 persons were Batanes (16,604), Camiguin (83,807), and Siquijor (91,066).


Largest City or Towns of Philippines

(Philippine Statistics Office 2010 Census March 30, 2012)

1. Quezon City - 2,761,720

2. Manila - 1,652,171

3. Caloocan - 1,489,040

4. Davao City - 1,449,296

5. Cebu City - 866,171


▪ REASONS WHY FILIPINO HAVE AN IMMENSEGROWTH OF POPULATION

1. Tradition of Having Big Families

2. Questions of Gender

3. The Male Macho Image

4. Unsatisfactory/Ineffective Family Relationships

5. Economic Reasons

6. Contraceptive Methods

7. Educational Background


▪ PROBLEMS ON POPULATION GROWTH IN THEPHILIPPINES

1. Environmental Problems

2. Social Problem

3. Economic Problem

4. Educational Problem

5. Health Problem

6. Spiritual and Moral Problems

7. Food Supply

8. Problems on Destruction of Nature

SUPPLEMENTARY READING

Giant Clam (Tridacna Gigas)The largest and heaviest mollusc

in the world.Quite large at 4 feet 6 inches and

quite heavy at 200-500 kilos. Their shellsmay reach up to 1.5 meters in length.Once fully grown, Giant Clams cannotcompletely close their shells anymore.These large creatures occupy coral reefhabitats, typically within 20 meters if thesurface. They are stationary or unable tomove from their position in the coral reef.They are found in shallow waters of thePacific Ocean, from Thailand and Japan toAustralia and Micronesia.

population dynamics

Environment

particular population

size of population

population of people

population dynamicsmodule

population density

land lesson

number of species

organism spreads