Chapter 2 - Biodiversity Flashcards
Population
a group of organisms in the same species that inhabit a given area.
Community
The populations (of different species) that inhabit an area.
Ecosystem
The biological community (populations) and the physical (abiotic) environment.
trophic levels
food chains/connecting system of consumption and interactions
niche
role in the ecosystem, what an organism does, where, and when
Primary Succession
starting with rock ex. volcanic eruption
Succession
predicable change in community, due to events.
Secondary Succession
forest after being cut down
Carrying Capacity
how many individuals an area can hold
Species richness
number of spices found in a particular area
Species diversity
includes richness but also how even the abundance of species is. Shannon-Weiner
alpha diversity
the number of species in an area
Beta diversity
variability of species composition along a geographical gradient. ex. series of mountains, lakes
Gamma Diversity
the number of species in a large area, areas that consist of more than one type of ecosystem.
Keystone species
Low biomass, high impact
Dominate species
High biomass, high impact
rare species
Low biomass, low impact
Common species
High Biomass, Low impact
Population
group of individuals of a single species that can and do mate with each-other. (live in a given area)
Gene
location on a chromosome - locus codes for a specific polypeptide
Alleles
Different versions of a gene
Gene pool
the number and frequency of alleles in the population.
Genotype
what alleles are present
Phenotype
the expression of the genotype
Polymorphic genes
genes with more than one allele
Evolution
change over time in the genetic composition (frequency of alleles) of populations
heritable traits
traits passed onto the next generation
Differential reproductive success
success of individuals with varied traits
Relative fitness
not just how many offspring, more offspring than others produce
Genetic drift
change in the frequency of alleles due to sampling. affects small populations more
Population bottleneck
Big population - bottleneck - small population - big population with less diversity.
founder effect
colonization of a small non varied group of a population.
Geneflow
movement of alleles in or out of a population changes frequency over time.
Does natural selection decrease or increase variation
decrease
does genetic drift +/- gentic varation
decrease
gene flow +/- genetic variation
increase
Species
groups of natural populations that interbreed or could interbreed under natural conditions but are relatively isolated from other groups.
Barcode DNA
DNA analysis process
Cryptic Species
one form of different species looks the same
Speciation
the formation of new species
Sympatric speciation
overlapping ranges
Allopatric speciation
Separate
Evolutionary radiations
High rate of speciation, island immigrants may expand their realized niche.
Fundamental niche
what could the species do without limiting factors
Patterns of biodiversity
increases as you get closer to the equator
