Lecture 16: Disease and population dynamics Flashcards
True or Flase:
Fecundity Schedule only tracks Male matting patterns, and the number of mates they take on.
False:
A Fecundity schedule only tracks females, with sex ratios almost always being 1:1
What is a Fecundity schedule?
a tabulation of birthrates
for females of different ages in a population
What is Net reproductive rate?
The average number of offspring produced by an individual in a population.
What is Geometric rate of increase?
The ratio of the population size at two points in time.
What is Generation Time (T)?
The average age within a population at which a female gives birth to her offspring. Can be greater than age of first reproduction if female reproduces more than once.
What is the relationship between organism size and generation time?
The larger the organism the longer the generation time.
What is the Per-capita rate of increase?
Equal to per-capita birth rate minus per-capita death rate.
If per capita rate of increase is greater than 0, then what is happening to the population?
It is growing
If the per capita rate of increase is less than 0, then what is happening to the population?
It is shrinking
What is the impact of disease upon a population?
Disease can alter individual fitness and impact population dynamics.
What is a disease?
A “atypical” condition in a living organism that causes some sort of physiological impairment.
What can cause a disease?
Genetic abnormalities, exposure to toxins, and interaction with other organisms,
All disease-causing organisms are _____/_____.
Exploitative/selfish
What is Direct transmission?
Transmission through physical contact with an already infected host.
What is indirect transmission?
transmission through touching a surface that physically touched an infected individual.
What is horizontal transmission?
Transmission among individuals of the same generation
What is vertical transmission?
Transmission from one generation from another ( parent to offspring )
Evolution by natural selection requires that traits be _____
heritable
And traits must produce different levels of fitness among genotypes.
What is Disease fitness?
The fitness (measured as net reproductive rate) of a disease.
For Horizontally transmitted disease, the number of hosts are proportional to what?
number of
new hosts is proportional to the number of
disease progeny (It isn’t dependent on the
fitness of the host.)
For vertically transmitted diseases, what is the Number of hosts dependent upon?
number of
new hosts is dependent on host fitness.
Review diagrams on slides 25-26
D O I T
What is Isolation?
Separate sick individuals
from healthy individuals
What is Quarantine
Separate individuals who have
been exposed to the illness, even if
they are not presenting any
symptoms of the disease.
What is better isolation of Quarantine?
Isolation is often better for smaller outbreaks.
As soon as they get larger, then a mixture of both becomes the most effective.
How do we stop the spread of disease?
Vaccines
What is Herb immunity?
It is when vaccination rates
are high enough that the population growth rate
(r) of the pathogen is negative, and it may go
extinct.
Why are diseases with high
transmission rates so hard to
eradicate?
A. It is more difficult to make vaccines for highly
transmissible vs. less transmissible diseases
B. While highly virulent, they have small
populations that are difficult to find and
remove
C. They have high population growth rates,
making it hard to achieve herd immunity
C. They have high population growth rates,
making it hard to achieve herd immunity
