2nd test Flashcards
competitive exclusion
Two different species cannot use the same resource at the same time which leads to
Resource partitioning
sharing of resources at different times in different ways (temporal, spatial, morphological)
habitat corridors
paths where two populations meet. Usually, these areas are the spaces on rivers and roads and areas that allow organisms to cross
metapopulations
populations made up of the same species
inbreeding
breeding of closely related animals
Density Dependent Factors
biotic factors (disease, food animals)
Density Independent Factors
abiotic factors (weather)
K-selected species
large body size, long life expectancy, production of fewer offspring, longer gestation period, longer to mature (hover close to carrying capacity)
r-selected species
rapid development, high reproductive rate, small body size, early reproductive age, short lifespan (exponential growth, j-shaped graph)
primary succession
the beginning step of ecological succession after an extreme disturbance Begins with bare rock and then undergoes physical weathering, allow
secondary succession
Begins with soil and when an ecosystem reestablishes itself. It happens after natural disasters like fires flood earthquakes and can happen anthropologically like clearing a forest
Species richness
biodiversity; amount of species in an area
the equation for percent change
(new- OG/original) x 100 = % Change
Population Growth Rate
Number of organisms born (rate of reproduction) – the deaths
Intrinsic Growth Rate
Growth rate under perfect/ideal conditions (All resources available, no natural disasters, absence of disease and predators)
Produces j graph
Logistical Growth Rate
the actual/realistic growth starts off as s-shaped then plateau as organism reach their carrying capacity (starts exponentially)
keystone species
a species on which other species in an ecosystem largely depend, such that if it were removed the ecosystem would change drastically.
island biography rule
islands closer to the mainland, and larger in size have more biodiversity
Genetic drift
random mixing of genes, reproducing with members of other populations, leads to biodiversity (good) (absence of recessive traits)
Bottleneck Effect
happens when many members of a species or population are eliminated (anthropogenic or natural), the survivors then have a reduced gene pool
Founder Effect
a new population is established by a small group from a larger population, and the gene pool is reduced
niche generalist
can eat many different foods and live in multiple niches (raccoon)
Niche specialist
narrower diet and area of living (Koala)
population density
number of organisms in an area
