chapter 2 Flashcards
Biodiversity
complete range of species and biological communities, genetic variation within species and all ecosystem processes
Types of biodiversity or biological diversity
- Species diversity-all species on earth, including single celled bacteria, Arachne, protist and multicellular species: plants, fungi, animals.
- genetic diversity- genetic variation among species in one population and among geographically separate population of species
- Ecosystem diversity- diff. biological communities and processes involving the chemical and physical environment.
Species diversity
Entire range of evolutionary and ecological adaptations of species to particular environments.
Species concepts:
Morphological: a group of individuals that is morphological, physiological, or biochemical distinct from other groups. (phenotype: is what differentiates: look diff=diff species)
Biological: A group of individuals that can potentially breed among themselves in the wild and that do not breed with other individuals of other groups. es: mules horses and donkeys)(hybrid not species can’t reproduce anymore)
Scientific names
Taxonomists use
Taxonomists use morphological and genetic information to identify species . (use structure and diff. markers on genes)
Species concepts:
Morphological: a group of individuals that is morphological, physiological, or biochemical distinct from other groups. (morphology also a problem to realize that individuals in the same species might look diff.) (morphology- form and structure appearance)
Biological: A group of individuals that can potentially breed among themselves in the wild and that do not breed with other individuals of other groups.(mostly used by evolutionary biologists difficult to use)
binomial
each species has a given unique two-part name
hybrids
can’t reproduce anymore, intermediate forms that blur the distinction between species that are related but distinct
cryptic biodiversity
widespread existence of undescribed species that have been wrongly classified and grouped with a similar appearing species.
Region 1
if question asks for saving mountain it is region 1 because it has the highest # for alpha. greater number of species per mountain
Region 2
save species. Choose region 2 since it has the highest gamma, it has the highest number of species.
Region 3
save uniqueness. It has the highest beta, diff. species each mountain.
Genetic diversity denoted in 3 ways
-spessies richness (alpha diversity)
-Gamma diversity-# of species found across a large region with a number of ecosystems
-beta diversity- links the alpha and gamma. represents the rate of change of species composition as one moves across a large region. gamma/alpha
Genetic variation:
Individuals within a population may be genetically different from one another to varying degrees.
- Population:
a group of individuals (can be few or millions) at a certain place that can potentially mate with one another and produce offspring. Species can have one or more pop.
Genetic variation within a species can allow the species to
adapt to environmental change.
genes
alleles
mutation
fitness
genes-blueprint for proteins of life
alleles-diff. forms of gene
mutation-where differences arise because of alleles
fitness- ability to survive and reproduce
gene pool
total of genes and alleles in a population
polymorphic genes-
heterozygous-
homozygous-
rare species=
-genes that have more than one allele
-receive diff. allele from parents
-receive same allele from parents
=less genetic variation vulnerable to extinction
Ecosystem diversity
Results from the collective response of species to different environmental conditions.
Community
Community: all the species that occupy a particular locality and the interactions among those species.
Ecosystem
Ecosystem: A biological community together with its associated physical and chemical environment.
Succession
Succession: Gradual process of change in species composition, community structure, soil chemistry, and microclimatic characteristics that occurs following natural or human-caused disturbance in a community.
primary-ex: mountain with ice cap melts with climate change, first time ever it will have life.
secondary-there was already vegetation
ex; humans crop area and abandon the area, forest comes back.
ecosystem process
-water cycles(evaporation), nutrient cycles(soil- decomposition), energy cycles(photosynthesis)
limiting resource can restrict what
can restrict pop. size and distribution of species.
Species interactions
predator-prey (hunt and kill prey)
+mutualism +-reach higher densities when they occur together than when one of the species is present. -symbiotic relationship-cannot live without the other
+Commensalism0
-amensalism0
+parasitism-
parasitoids-kill the host -not immediate death
carrying capacity
of resources of an ecosystem that can support species
-amount of resources available to sustain a pop./species
trophic levels
1st trophic level-primary producers-energy from sun-usually has the greatest biomass
2nd-herbivores (primary consumers) eat plants
3rd-Carnivores-obtain energy by eating other animals (secondary consumers) some are omnivores eat both
Decomposers-feed on dead plant and animal tissues and waste, release minerals
species interactions
food chain
food web
keystone species
-loss of these species creates
Food chains- very specific feeding that species have-only feed on one species
Food webs-more complex, competition, feed on several diff. species.
Key stone species: strongly affect the abundance and distribution of other species in an ecosystem. ex: ocelot
-may be top predators
-loss of these species creates a trophic cascade-great loss in biodiversity and dramatic changes in vegetation
Guild
species at the same trophic level that use approximately the same environmental resources=is a guild of competing species
keystones
-loosing keystone species=
-ecosystem engineers-greatly modify physical environment.
-loosing keystone species=extinction cascade -results in degraded ecosystem with lower diversity at all trophic levels
-keystone resources es: deep pools, streams, ponds during dry season
ecosystem integrity
ecosystem is intact and functional
stable ecosystem
remain in the same state
resistance
maintain same state despite disturbance
resilience
being able to return to the same state quickly after disturbance.
How many species exist?
richness areas
- 1.5 million of species have been described
Estimations: 5 to 100 millions
Richness areas:
Tropical forest
Coral reefs
Deciduous forest
Deep sea
Mediterranean climates
-200,000 new species each year
most abundant species
insects
new methods
-techinical climbing equipment to research top of tropical trees
-use DNA tech to investigate the interior of leaves of healthy tropical trees
-use new sampling techniques have revealed a diversity of new bacterial communitites
Distribution of species
-most species rich environments appear to be tropical rain forests, coral reefs, deep sea
greater diversity of species=
tropical rain forests
patters of diversity are parallel by patterns in
marine species, again with an increase in species diversity toward the tropics
environmental variation=
genetic variation
-mostly in hot area, abundant rainfall.
