Exam 2 Topics Flashcards
(26 cards)
interspecific competition
Name 6 types
competition among different species for same resources
Consumption Preemption Overgrowth Chemical interaction Territorial Encounter
intraspecific competition
competition among members of the same species
Population size =
Density x area
r selection
High fecundity
Short life spans
early age first reproduction
low investment in offspring
K-selected species
allocate most resources towards growth and defense
invest heavily in offspring
(Most mammals)
N(t) =
population size at a particular time
r =
births - deaths
symbiosis
Two organisms using each other
Predation
Parasitism
Competition
Mutualism
Commensalism
Type 1 survivorship curve
High survivorship until old age
- humans, mostly mammals
- more K selected species
Type 2 survivorship curve
Mortality of an individual does not depend on age
-mostly birds, rodents, reptiles
Type 3 survivorship curve
Mortality rates are very high early in life then relatively constant
- creatures that have thousands of young
- fish, seeds
x =
Age classes
nx =
of individuals from the original cohorts that are alive at the specified age (x)
lx =
The probability at birth of surviving to any given age (x)
nx/original total amount of cohort
dx =
Age specific mortality
( how many died in an age class )
n0-n1
qx =
age specific mortality rate
of individuals that died in a given time interval (dx) divided by the # alive at the beginning of that interval (nx)
-ex. d1/n1
Lx =
Average # of individuals alive during the age interval x to x+1
-ex.
(n1+n2)/2
Scramble competition
1 of 2 types of intraspecific competition
When a resource is used by one species and hurts the survival of the that species total population if it dwindles.
Ex. Cows and grass
Contest competition
1 of 2 in intraspecific competition
There is one clear winner and one clear loser.
Ex. A wolf eats a carcass, and fights other wolf off. Other wolf doesn’t eat
Interference competition
Basically fighting
Ex. Male deer fighting during rut
Exploitation competition
When individuals indirectly affect the well being of another by using a shared resource.
If a shared resource is used by one, there’s less for someone else
Competitive exclusion principle
Two species requiring the same resource cannot coexist
Whoever gets the slightest advantage will take over
Constituitive defenses
Fixed features
Ex. Turtle shell
Induced defenses
Activated when attacked
Stink bug, skunk
