This document discusses several topics related to population ecology, including: - Populations cannot grow indefinitely due to limited resources and competition. Their distribution, age structure, size, and density change in response to the environment. - Changes in growth rates of invasive, keystone, and ecosystem engineer species have a greater impact on biodiversity than other species. Disease, introduction of nonnative species, and chemicals like pesticides also affect populations. - Basic population patterns include clumped, uniform, and random distributions. Most plant and animal populations exhibit clustering where resources are available. - The four variables that determine population growth are birth rate, death rate, immigration rate, and emigration rate. - Carrying capacity is determined by

1. Ch. 5, part 2
Miller & Spoolman, 16th ed.

3. Populations cannot grow indefinitely because
resource are limited and there is competition for
those resources

4. The study of:
 Distribution
Age structure
Population Size
Population Density
These things change in
response to changes in
the environment

5. Changes in the growth rate of
Invasive species
Keystone species
Ecosystem engineers
Have a greater impact on the biodiversity of an area
than other species

6. For example:
How disease affects a population
How the introduction of a
nonnative species affects a
population
How the presence of chemicals
like pesticides affect populations
Studying these things helps us
identify keystone species

8. 3 basic patterns:
Clumped
Uniform
Random

9. Most common in both plants and animals

10. Nouns of Assemblage
A gang of elk
A wilderness of monkeys
A field of runners
A murder of crows
A parliament of owls
A kaleidoscope of butterflies
A flamboyance of flamingos
A raft of otters
A muster of peacocks
A drift of swine
A charm of finches
A tower of giraffes
A smack of jellyfish
A business of ferret
An unkindness of
ravens

11. 1. Cluster where there are resources
2. More likely to find resources if they work together
3. Protection from predators
4. Teamwork to catch prey
5. Mating group and/or help raising young

12. Especially in plants
Secrete chemicals that prevent others from growing
nearby
Increases chances of getting the water and soil nutrients
it needs

13. Pretty rare
Occurs when there is no good reason for the other
types

16. 4 variables
Birth rate (natality) +
Death rate (mortality) -
Immigration rate +
Emigration rate -
Let’s try some math!

21. What might be some of the limitations of each
method for counting individuals in a population?
Consider:
Migration
Birth rate
Death rate
Other factors?

22. A population’s capacity for growth under ideal
conditions
General rule of thumb:
Big things have low biotic potential
Little things have high biotic potential
Blue whale &
calf
ants
E. O. Wilson
studied ants
mostly
Give an example of an
organism with low biotic
potential and an organism
with high biotic potential

23. The rate at which a population would
grow if it had unlimited resource
Species with high “r” usually:
Reproduce early in life
Have short generations
Can reproduce often
Have lots of offspring each time
So what’s the difference between biotic potential and
intrinsic rate of increase?

24. r-selected speciesr-selected species
High biotic potentialHigh biotic potential
Lots of offspringLots of offspring
Little or no parental careLittle or no parental care
UsuallyUsually opportunist speciesopportunist species

25. K-selected speciesK-selected species
Low biotic potentialLow biotic potential
Few offspringFew offspring
Lots of parental careLots of parental care
Usually competitive speciesUsually competitive species
22 mo. Gestation, 522 mo. Gestation, 5
years between birthsyears between births
9 mo. Gestation,9 mo. Gestation,
8 years between8 years between
birthsbirths

29. r-selected K-selected
Size (usually)
Energy spent on offspring
Number of offspring produced
Time to maturation
Life expectancy
Lifetime reproductive events
Survivorship curve
Example species
Work together to create a T-
chart

31. The number of individuals in a
given volume

32. • Competition for resources
• Predation
• Disease
• Poisoning
• Human Harvesting

33. • Natural disasters
• Global warming
• Ozone depletion

35. The combination of all the factors that limit the growth of
a population
Together these factors determine the carrying capacity (K)
of the population

37. What are the letter symbols we’veWhat are the letter symbols we’ve
learned so far and what do they standlearned so far and what do they stand
for?for?

39. Difference in genes
among members of a
population
A very important factor in
the long term health and
survival of a population

40. Fluctuations in gene frequenciesFluctuations in gene frequencies
in a small population from onein a small population from one
generation to the nextgeneration to the next
The smaller the size of the population, the
more likely there is to be a major shift in allele
frequencies

41. Founder Effect - a small group
of individuals becomes
separated from the larger
population.
They may have less genetic
diversity than the larger
population

42. When only a small
group survives some
change in the
environment
Lack of variation means
less adaptability
Humans sometimes create
bottlenecks in other species

44. Individuals in a small
population mate with
each other
Increases the frequency
of defective genes

45. The minimum number of individuals needed to
maintain a species for the long term
Less than 400 left
Less than 50 left in the wild

48. 0 – not even with prompting can I explain this
topic
1 – with some prompting I could explain some
of it
2 - I get the basics
3 – I understand it beyond just basic info
without help
4 – I can apply what I know to a test question

50. Fluctuates a little above and below carryingFluctuates a little above and below carrying
capacitycapacity
Found in stable ecosystems like rain forestsFound in stable ecosystems like rain forests

51. PopulationPopulation
explodes, thenexplodes, then
stabilizes at a lowerstabilizes at a lower
level; often tied tolevel; often tied to
the seasonsthe seasons

52. Boom and bustBoom and bust
Closely tied to predator prey and/orClosely tied to predator prey and/or
seasonalityseasonality

53. 1960
Year
Moosepopulationsize
2,500
Steady decline probably
caused largely by wolf
predation
2,000
1,500
1,000
500
0
1970 1980 1990 2000
Dramatic collapse caused by severe
winter weather and food shortage,
leading to starvation of more than
75% of the population
Irregular

54. Jaguars in the Brazilian rainforest
Mice in the Australian outback

60. What are the pros and cons of:
Rapid population growth?
No population growth?
Declining population?
Economic
Social
Environmental

61. Stump the class
• Each person write one multiple choice
or short answer question on your
index cards from Ch. 4 or 5
• Question on one side, answer on the
other
• Share your questions with your team
and revise if necessary
• Give your cards to Beck to share with
the class