Types of diversity:

• Genetic
• Species
• Ecological
• Functional

Genetic Diversity

variety in the genetic makeup among individuals
 

Species Diversity

variety among the species or distinct types of organisms found in different habitats of the planet
 

Ecological Diversity

variety of forests, deserts, grasslands, streams, lakes, oceans, coral reefs wetlands & other biological communities
 

Functional Diversity

biological & chemical processes or functions such as energy flow & matter cycling needed for the survival   of species & biological communities
 

Phytogeography

Plant distributions

Zoogeography

Animal distributions

Photosynthesis

the process of converting CO2 and H2O into carbohydrate and O2 using sunlight as the energy source
 

Photosynthesis occurs in:

the cells of plants which contain chloroplasts, which contain the pigment chlorophyll

Limitations of photosynthesis

•  rate of respiration
• availability of water
• rate of evaporation & transpiration

Biomass

useful chemical energy created from photosynthesis

Net Primary Productivity
 

the net photosynthesis for a given community;  this considers all growth & reduction factors that affect the amount of biomass fixed in an ecosystem
 

NPP =

photosynthesis - respiration

Food webs (food chains)
 

the pathways that energy may take from plants through various trophic levels (what eats what?)
 

Trophic level

each step or stage of the food web

Autotrophs

those that make own "food"

Heterotrophs

those that must consume other organisms to get the energy (food) they need; Animals
 

 3 types of heterotrophs

herbivores (primary consumers),
                        carnivores(secondary consumers), omnivores

Decomposers

those that obtain their energy by breaking down dead organic material  

EX:  Bacteria,    fungi
 

Ecological Efficiency

how well energy is passed from one system to another, say along a food chain or web
 

Ecological efficiency decreases:

as energy is moved along a food pathway or chain

Evolution or Biological Evolution
 

the change in a population’s genetic makeup, gene pool, through successive generations
 

*   all species descend from earlier, ancestral species
 

Macroevolution

long-term, large-scale changes that lead to new species (speciation), and the loss of other species
 

Microevolution

small genetic changes that occur in a population

* mutations

Mutations are:

• random & unpredictable   
• only source of totally new genetic raw material (without human help)

• relatively rare events

Natural Selection
 

process by which a particular beneficial gene or set  of genes is reproduced in succeeding generations more than other genes.
        This leads to a population of organisms with a greater proportion of individuals better adapted to certain environmental conditions.
 

Adaptation or adaptive trait
 

any genetically controlled structural, physiological, or behavioral characteristic that helps an organism survive & reproduce under a given set of environmental conditions.
 

EX’s:   structural adaptations:
 

physiological adaptations:
 

hibernation,      chemical protection

behavioral adaptations:

migration,    various mating behaviors

Ecological Niche

total way of life or role of a species in an ecosystem;  all physical, chemical, & biological conditions a species needs to live & reproduce in an ecosystem
 

Habitat

the physical location in which a species lives
 

Species

group of organisms that resemble one another in appearance, behavior, chemical makeup & processes,  & genetic structure
 

Generalists

species with a broad ecological niche;  

can live in many different habitats, eat a variety of foods & tolerate a wide range of environmental
        conditions;    

less prone to extinction
 

Ex. of generalists:

humans, flies, cockroaches, mice & rats, raccoons, coyotes, channel catfish, various weed species, etc.
 

Specialists

species with a narrow ecological niche;

may live in only one type of habitat,  tolerate only one type or a few types of food,  tolerate only a narrow range of environmental conditions; 

more prone to extinction
 

Ex. of specialists:

red-cockaded woodpecker, giant pandas, snail kite, numerous tropical rain forest species
 

Native Species

species that normally live & thrive in a particular ecosystem in which they evolved or are 'naturally' found
 

Ex. of native species

American bison, American alligator, etc
 

Nonnative Species

species that migrate into an ecosystem or are deliberately or accidentally introduced into an ecosystem; also known as exotic, alien, or introduced species
 

Ex. of nonnative species

 kudzu, Argentine fire ants, nutria, etc
 

Indicator Species

species that serve as early warnings that a community or ecosystem is being degraded
 

Ex. of indicator species

many birds, frogs, & toads
 

Keystone Species

species that play roles affecting many other organisms in an ecosystem
 

Ex. of keystone species

wolf, leopard, lion, sea otter, great white shark, various bees, bats, & ants
 

How quickly can a species adapt?
 

1)   A change in environmental conditions can lead  to adaptation only for traits already present in the gene pool of a population
2)   The population’s ability to adapt can be limited by its reproductive capacity
3)   Even if a favorable trait is present, most of the population would have to die or become sterile so individuals with the trait could dominate & pass
        the trait on
 

Speciation

formation of 2 species from one species as a result of divergent natural selection in response to changes in environmental conditions
 

 Geographic Isolation

separation of populations of a species into different areas for fairly long times
 

Reproductive Isolation

long-term geographic separation of members of a particular sexually reproducing species
 

Extinction

complete disappearance of a living species from the Earth;   

happens when a species cannot adapt & successfully reproduce under new environmental conditions or it evolves into one or more new species