Biocore ecology

• 1. Descent with Modification
• 2. Mechanism for Change (eg. reproductive isolation, changes in gene frequency)

The process that eliminates those individuals that are less likely to survive and reproduce in a particular environment, while allowing other individuals with traits that confer a greater reproductive success to increase in numbers

combines Darwin's theory with a modern understanding of the principles of inheritance and a recognition that natural selection is only one (and perhaps not the most important) of the forces that cause change

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the study of the relationships between organisms or groups of organisms and their environment

the biota (living and dead organisms), atmosphere, hydrosphere, lithosphere, and their interconnections

regional patterns of daily weather; pattern over time in one place

local, site-specific weather phenomena

the setting within which an organism can function as a living system and outside of which it is no longer capable of living

Open system: exchanges matter and energy with its surroundings

The levels of an environmental factor within which an organism can live

the levels of an environmental factor within which an organism performs best

The sum total of a species' relationship with the biotic and abiotic resources in its environment

An accumulation of inherited characteristics that ehance organisms' ability to survive and reproduce in specific environments

limits their species distribution

Major biotic assemblages of the earth, classified by the predominant vegetation life forms and characterized by the adaptations of organisms to that particular abiotic environment (climate)

the independent development of similarities among species as a result of their having similar selection pressures

display average precipitation and temperature of a particular location

dry

moist

an ecosystem dominated by grasses and having less than 1 mature tree per acre

• 1. Little Bluestem
• 2. Big Bluestem
• 3. Indiangrass
• 4. Side-Oats Grama Grass
• 5. Prairie Cord Grass

• 1. Wild Indigo
• 2. Pale Purple Coneflower
• 3. Rattlesnake Master
• 4. Yellow Coneflower
• 5. Silky Aster
• 6. Showy Goldenrod

forbs than grasses

Roots form mychorrhizal associations (a type of mutualism) with soil fungi. The fungi brings water and nutrients to the roots and the plant provides food to the fungi

• accumulates if not burned
• removal through burning stimulates increased growth & flowering
• shades ground and keeps ground temp cool
• habitat for many animals

• full sun
• strong, drying winds
• heat
• low soil moisture
• strong herbivore activity
• fire
• drought

• 1. Narrow leaves (prevents overheating by exposing surfaces to wind currents while at the same time reducing wind resistance)
• 2. Many vertical leaves (allows large photosynthetic surface areas exposed to plentiful light without shading neighbors)
• 3. Tips of leaves of some grasses held at an angle parallel to the sun, reducing direct exposure to damaging light)
• 4. Silica- deters insect grazers
• 5. Grass flowers are wind pollinated
• 6. growing points are at the bases of leaves, so if the tops are removed growth will continue
• 7. C4 photosynthetic pathway which is more efficient in warm weather

• 1. Small leaves and hairy leaves and stems reduce heat load through reflectance and convection, and helps w/ wind resistance
• 2. Thick leaves can reduce water loss and deter grazing
• 3. Chemicals in tissues, hairs, and spines reduce grazing pressure

• 1. seasonally changing cover
• 2. seasonal food availability
• 3. hot summers, cool winters, frequent drought
• 4. strong winds
• 5. fire

(eg cattle) these animals have a 4 chambered stomach that provides help in digesting grasses. Allows more efficient use of the food and allows animals to collect food and move on, thus escaping predators or fire

a group of organisms of the same species living together in the same place at the same time

looks at relationships of individuals in a population to each other and their environment

the number of individuals in a population.

number of organisms per unit of area or volume

resource abundance

• 1. harder for a predator to locate an individual in the population
• 2. organism to organism transmitted diseases are less common

• 1. protection from predators and from harsh environmental conditions
• 2. ability to specialize (take on roles)

areas of defined shape and size

Define: sampling technique for organisms that move to determine population size. Capture, mark, release, capture again later

• Equation: 
• Assumptions: (1) number of individuals caught the first time is the same proportion of the total population as the proportion of marked individuals to the total number caught the second time. (2) Marks did not fall off or affect survival (3) captures dispersed evenly into the population (4) Random capture (5) no immigration, emigration, births, deaths

• Spatial arrangement
• clumped, uniform, random
• Creosote Bush

identifiable steps an organism goes through from birth to death

the sum of the benefits an organism forfeits by not being able to perform some other activity during the time when it is engaging in a different activity

statistics related to inputs (births, immigration) and outputs (deaths, emigration) within a population

an age-specific summary of the survival pattern of a population

considers the influence of population density on population growth rates. Predicts fluctuations around carrying capacity, considering only density effects

• 1. introduced species (disease)
• 2. direct exploitation (hunting)
• 3. habitat destruction

• 1. narrow geographic range
• 2. narrow habitat requirements
• 3. small local populations

• the smallest number of individuals needed to perpetuate a population before extinction vortex begins
• size needed to have a 99% chance of survival for 100 years

a group of spatially separated populations of the same species

a population in which births exceed deaths. often produces more individuals than can be accommodated by available resources

a population in which deaths exceed birts or in which no reproduction occurs

• 1. determining MVP
• 2. inderstanding metapopulation structure and dynamics
• 3. determining habitat requirements

growth in a situation with unlimited resources and overlapping generations

exponential growth model equation

• maximum growth rate of which a species is capable
• intrinsic rate of natural increase. based on the biology of a species and achieved under ideal environmental conditions

realized per capita rate of increase (births - deaths) achieved under specific environmental conditions

net reproductive rate (how many offspring one female has)

• 1. no emigration or immigration
• 2. per capita birth and death rates are constant (r is constant)
• 3. growth is continuous
• 4. resources are unlimited and no other facotr is limiting growth

a species that is not native to the area; brought to the area on purpose or by accident by the activities of modern humans

predict how long it will take for a population to double

• logistic population growth model
• K = Carrying Capacity (maximum stable population size an environment can support

• 1. K is constant
• 2. each new individual added to the population casues an incremental decrease in the growth rate (population growth rate decreases as N increases)

• 1. # of offspring per breeding event
• 2. survival to and through reproductive age
• 3. age at first reproduction
• 4. length of reproductive period

• 1. many offspring
• 2. small offspring
• 3. little parental care
• 4. early maturation

• 1. few offspring
• 2. large offspring
• 3. extensive parental care
• 4. long maturation time

a group of species living together in the same place at the same time

the composition and arrangement of species within a community

• a measure of species abundance within a community
• 1. richness
• 2. equitability/evenness

number of species per unit area or volume

the relative abundance of a species

Shannon-Wiener Index

• 1. similar abiotic environmental requirements (overlapping ranges of tolerance)
• 2. dispersal to the site
• 3. interactions between different species that cause the community to function as a unit

• 1. differences in the complexity of physical environments
• 2. differences in the length of time the areas have been in place

potential negative effects for both organisms

one organism makes a living at the expense of another

both organisms benefit

a set of species that are potential competitors because they exploit the same resources (not necessarily in the same area)

competition within a species

competition between different species

predicts that 2 competitors can coexist, both with stable populations when intraspecific competition is stronger than interspecific competition

if two species are competing for the same limited resource, then one of the species will be able to use that resource more efficiently than the other and will eliminate the other

the environmental conditions within which a species might live in the absence of interactions with other species

the actual environmental conditions within wich a species lives because of restrictions imposed by interactions with other species

the tendency for characteristics to be more divergent in two sympatric populations than in two allopatric populations

live on the tissues of, but generally do not kill, hosts

dominant primary producer

the most abundant or most biomass

resude the populations of prey species

once species affects another through a third, intermediary species

• a theory to rpedict the number of species than an island can hold- based on inputs and outputs
• considers the influence of island size and distance from mainland on immigration and extinction rates
• -large/near islands will have more species than far/small islands

• a shift in species composition and community structure over time;
• the gradual and orderly process of change in an ecosystem

ecological succession in a location that has never supported a biotic community (eg. recent volcanic land mass)

ecological succession in a location where an existing biological community has been disrupted by a disturbance

early colonists modify the environment so it becomes less suitable for themselves and more suitable for other organisms

early colonists occupy the site and prevent other speices from colonizing

once present, species that can withstand environmental changes persist to remain resident

a non-abundant species whose presence helps maintain community structure, diversity and complexity. Without it the community could collapse (ex. starfish, eucalyptus tree)

a collection of interconnected communities distributed across a region

the study of the spatial arrangement of communities and how these patter change through time

 a small area, distinct in form and composition from the surroundings

the larger area surrounding a patch

passageway linking patches in a matrix

edge, surroundings, interior

patch size and isolation influence extinction and immigration rates and therefore species diversity

• Positive: isolation provides protection from exotic species, diseases, and other problems
• Negative: isolation may lead to inbreeding and the extinction vortex
• corridor connections help maintain diversity

establishing communites and then protecting them from unwanted change

the practice of assembling native plant and animal communites for the purpose of conserving, studying, understanding, and experiencing biodiversity and ecosystem services

focuses on the interconnections between the biota and the atmophere, lithosphere, and hydroshphere

• producers (autotrophs)
• heterotrophs
• primary consumers
• secondary consumers
• tertiary consumers
• detritivores

• sun's radiation
• heat

the conversion of light energy to the chemical energy of organic compounds by the producers of a system

total amount of energy produced

the amount that remains after energy needed for maintenance is used (respiration) and thereby lost as heat

the total energy taken in and used for growth, reproduction, and cellular respriation

the % of energy assimilated by an organism that becomes incorporated into new biomass

10% transfer rule

substances that don't diminish throughout trophic levels; gets more concentrated as you go up levels (eg. concentration of a chemical in fish)

• 1. abiotic factors
• 2. the activities of herbivores/consumers

usefel tool to trace energy flow and establish food webs based on what an organism has eaten

• 1. Nitrogen Fixation-  by bacteria on legume roots or lightening or other bacteria
• 2. Nitrification  by aerobic soil bacteria
• 3. Assimilation- uptake of ammonium or nitrate and incorporation into organic compounds by plants (by consuming)
• 4. Ammonification: conversion of N-containing organic compounds into ammonia
• 5.Dentrification- conversion of nitrates to N2 by anaerobic bacteria

• product of detritivores
• decomposed organic matter

• carbon enters the biosphere when autotrophs incorporate it into their biomass during photosynthesis.
• carbons leaves biosphere through cellular respiration