Ecology Bio 262 1st test
What is Ecology?
The study of relationships between organisms and the environment
Where has ecology of the individual been dominate?
the domain of physical and behavioral ecology
What is physical ecology?
work with the evolution of physiological and anatomical mechanisms by which organisms solve problems posed by physical and chemical variations in the environment.
Evolution
A process by which populations change overtime. Evolutionary theory guides physical and behavioral ecology.
What is behavioral ecology?
ecology focused on the evolution of behaviors that allow animals to survive and reproduce in the face of environmental variation.
What is Population Ecology?
Ecology centered on the factors influencing population structure and process. How the processes that affect and make up population structure are affected by non biological and biological components of the environment.
Levels of Ecology
Individual Ecology, Population Ecology, Ecology of Interactions, Community Ecology, Ecosystem Ecology, Landscape Ecology, Geographic Ecology (concerned with regions), and Global Ecology (concerned with our biosphere)
Ecology of Interactions
Study predation, parasitism, competition and such and how evolution effects these interactions.
Community Ecology
Concentrate on organisms inhabiting an area.
Ecosystem Ecology
Include physical and chemical factors influencing communities and focus on process such as energy flow and decomposition.
Landscape Ecology
study of the exchanges of materials, energy and organisms, especially among ecosystems.
Geographic Ecology
study of large scale and long term regional processes.
Global ecology
studies the highest level of ecological organization, the biosphere or earth.
Robert MacArthur
Study of 5 warbler species who lives in the same spruce trees in 1955. predicted that they were able to coexist because they fed on the insects living in different zones within the trees.
What is the important of scientific research?
It teaches us directly about nature and stimulates other studies that improve our understanding.
Stable Isotope Analysis
useful in the study of ecological processes- for example, identifying food sources, because the proportions of various isotopes differ across the environment.
American Redstart
Migratory Bird. How does it’s wintering habitat in Jamaica affect it’s breeding in America. Superior birds spend their winters in the productive mangrove habitat, the lesser birds live in the poor scrub habitat. Based on the different foods eaten in these habitats stable isotope analysis can tell us which bird was where.
Nutrients
the raw materials that an organisms must acquire from the environment to live.
Nalini Nadkarni
trees in temperate and tropical forests send out roots from their trunks and branches high above the ground to grow into epiphtye mats and extract nutrients.
Epiphytes mats
Epiphytes are plants that live on branches and trunks of other plants. They are not parasitic. the trap organic matter and form thick mats that supports a diverse community of plants and animals and provides nutrients for trees. Makes up for the low nutrient quality of tropical soil.
What are two approaches that provide insights into long-term and long-scale processes?
Studies of pollen preserved in lake sediments and evolutionary studies.
Margaret Davis
Pollen studies show that during climate change plants evolve (adapt) as well as disperse (change geographic distributions).
Adaption
evolutionary processes that increase an organisms ability to live and reproduce.
Macroclimate vs Microclimate
What weather stations report vs climatic variation on a scale of a few kilometers, meters or even centimeters usually measured over shirt periods of time.
What influences Microclimates?
altitude, aspect, color of the ground and presence of boulders among other things. In water the physical nature and in soil the physical make-up could affect the microclimate.
Aspects and the Norther Hemisphere
The slope of the region. In the North the shaded areas are on the northern aspects of hills, mountains and valleys because the face away from the equator. Thus North vs South slopes can have very different microclimates, vegetation and organisms.
Plants create microclimates because they shade the landscape
It’s true, specially in deserts yo.
Plants create microclimates because they shade the landscape
It’s true, specially in deserts yo.
Beaches in New Zealand
Though Black and white beaches in New Zealand have nearly identical macro climates because of their diff colors they have radically different micro climates.
2 ways organisms stay away from the heat through geography?
Underside of stones and burrows.
What’s special about the temp of aquatic environments?
There is a lot of stability in the temps because of water’s high specific heat, high latent evaporation ability, high heat given off when freezing (latent heat of fushion), and lots of thermal stability when the water body is large.
Riparian vegetation
vegetation that grows along rivers and streams and influences the micro climate via shade.
Temperature and performance of organisms
most species preform best in a fairly narrow range of temperatures.
Richard Levins
mathematical approach via the principle of allocation. Also concluded that as a population adapts to a particular set of environmental conditions, its fitness in other environments is reduced.
Principle of Allocation
If an organism allocates energy to one function, such as growth or reproduction, it reduces the amount of energy available to other functions, such as defense.
Albert Bennett and Richard Lenski
Study microbial populations to show the first support for Levin’s principle of allocation. Selective fitness for 20*C had been accompanied by a loss in fitness at higher temperatures.
Extreme temperatures and photosynthesis
Extreme temps generally reduce the rate of photosynthesis.
acclimation
short-term physiological adjustments involving physiological, not genetic, changes in response to temperature. Usually reversible.
psychrophilic vs thermophilic
Cold-loving vs heat-loving
hyperthermophilies
most heat-loving microbes
K. Schmidt-Nielsen
Heat balance equation
Heat balance equation
Hs=Hm +/- Hcd +/- Hcv +/- Hr – He

Or total Heat= Heat GAINED from metabolism and heat gained or lost via Conduction and heat gained or lost via convection and heat gained or lost via electromagnetic radiation and Heat LOST through evaporation.

Metabolic Heat
Hm is the energy released within an organism during the process of cellular respiration
Conduction
Hcd Transfer of heat between objects in direct physical contact.
Convection
Hcv is the heat flow between a solid body and moving fluid, (water or air).
Radiation
Hr is the radiation given off by all objects above absolute 0. Includes infrared radiation.
evaporation
He you lose heat due to the ability of water to absorb large amounts of heat as it evaporates.
Poikilotherms
Body temperature varies directly with the environment. No regulation
Ectotherm
use external energy sources to regulate temperature
Endotherm
can use metabolic energy to regulate temperature.
Homeotherm
a subset of Endotherm that maintains a relatively constant internal environment. (Birds and mammals)
Heat equation for a hot desert plants or artic plants
evaporation cooling not an option because of water scarcity so. Hs=Hcd +/- Hcv +/- Hr. Thus they can decrease heating by conduction, increase rates of convective cooling or reduce rates of radiative heating.
How do desert plants regulate?
small leaves give high rates of convective cooling, reflective surfaces give low rates of radiative heat gain. (pubescent leaves) . Orienting leaves parallel to the rays of the sun or by folding them at midday, when sunlight is most intense.
How Arctic Plants regulate?
Increase their rate of radiative heating and or decrease their rate of convective cooling. They absorb light with dark pigments. Orient their leaves perpendicular to the sun’s rays. Also a cushion growth that hugs the ground increase radiative heating and reduces convective loss. Cushion growth can heatt heat the plant up 10*C higher than air temp.
How do tropical alpine plants regulate?
daily fluctuations from freezing at night to summer during the day. Giant rosette growth has allowed it to adapt to the extremes. retain dead leaves to insulate the stem from freezing. dense pubescence helps it conserve heat by creating dead air space above the leaf to reduce convective heat loss. retaining large amounts of fluids allows it to store heat during the day to keep for night.
Thermal Neutral zone
The range of temperatures over which the metabolic rate of a homeothermic animal does not change. Outside this zone an endotherm’s metabolic rate will rapidly increase. shivering at low temps and evaporative cooling at high temps.
two groups of thermal neutral zones?
tropical species and humans have narrow zones while arctic species have broad zones. Both types include 35 to 40*C in that zone.
Aquatic environments limit the possible ways organisms can regulate their body temps by:
increasing conductive and convective heat losses. The potential for heat loss is very great, especially for gill breathers.
Bernd Heinrich
Looking at moths he became convinced some insects can thermoregulate by endothermic means. Came up with the idea that moths regulate by using thier circulatory system to transport heat to abdomen to cool the thorax.
Skunk Cabbage
Using it’s large root of startch it can eleveate it’s temperature to protect it’s inflorescences(flowers) from freezing and to attract pollinators.
How to organisms survive extreme temperatures.
Many times by entering a rest stage. 1) inactivity and taking shelter, 2) reducing metabolic rate and body temperature through aka torper or a longer hibernation in the winter or estivation in the summer.
Why hibernate?
It saves energy which can give the animal a selective advantage when energy supplies are inadequate for metabolic needs.
Anette Baur
Snails went extinct dude to the higher temperatures at 8 sites from the thermal radiation of nearby urbanized areas.
Most trophically diverse organisms?
Prokaryotes including bacteria and archaea. They can be photo, chemo, or hetrotrophic.
What type of light is important in temperature regulation?
Infared.
What type of light drives photosynthesis?
visible or photosynthetically active radiation/PAR.
Solar spectrum percents?
45& PAR, 55% Infared & rest UV.
Photon flux density
number of photons striking a square meter surface each second.
photorespiration
occurs in the lgiht, consumes energy and produces CO2. Noo!
C3 photosythesis
Regular way. CO2 and a 5 carbon RuBP makes rubisco or PGA a 3 carbon acid. Since photorespiration becomes a big problem for this method during hot dry periods desert plants have adapted.
C4 photosythesis
Fixes carbon without light. carbon fixation and light-dependent reactions occur in diff cells. Conserve water using PEP and CO2 to 4 carbon acid. goes to bundle sheath where it changes back to CO2 at high levels to react with RuBP yay.
CAM photosynthesis
Carbon fixed at night with PEP and CO2 to 4 carbon acid. during day it’s broken down to pyruvate and CO2 and photosynthesis occurs. Very efficient water use.
Chemosynthesis
bacteria do 2H2S + O2 -> 2S + 2H20 + Energy. Can be free living or in tissues (like the giant tube worm). Nitrifying backteria that go ammonia to nitrite to nitrate are super important.
Most imporant 5 elements in living things?
Carbon, Oxygen, Hydrogen, Nitrogen, Phosphorus.
Challanges herbivores face:
Lower levels of nitrogen in plant tissues, plant physical and chemical defenses. Cellulose and Ligin are strong defenses that most animals can’t digest anyways.
What do tannins do?
bind to plant proteins inhibiting their breakdown. decreases the nutritional value of plants.
What area of plants have more chemical defenses?
Tropical plants.
Problems faced by detritivores:
foods poor in nitrogen (dead plants have about 1/2 the nitrogen as living plants).
Problems faced by carnivores:
Prey is nutritionally rich yay, but they have master defenses: antomical, camouflage, behavioral.
Mullerian Mimicry
Toxic mimics Toxic. M to M.
Batesian Mimicry
Harmless Mimics Toxic.
Prey-predator interactions:
Predator force prey to increase defense levels, which forces predator to increase their hunting abilities.evolutionary race.
Size-selective predation
prey often selected by the size a predator can catch and subdue. Especially correlated among solitary predators.
Energy Limitation
All organisms taking in energy at a limited rate.
Pmax
max photosythesis rate.
Isat
level of irradaince or photonflux density required to saturate photosynethsis.
Shade plants and energy limits:
rates level off a lower irradiance and are often damaged by high irradiance.
Net photosynthesis
Gross CO2-CO2 produced by plant respiration.
Functional responses
Type 1: feeding rate increases linearly as food density increases then levels off abruptly a some maximum rate. (animals have no processing time) Type 2: feedings linearly at first, then more slowly at intermediate and then levels off at high food density. MOST COMMON. Type 3: low food density there is a slow increase at intermediate density there is a steep increase and at high density it levels off.
Optimal foraging theory
if energy supplies are limited an organisms can’t maximize all life functions. it must allocate it’s energy via principle of allocation. * attempts to predict what consumers will eat, when and where they will feed.
Optmization
predators will continue adding different types of prey to their diet until he rate of energy intake reaches a maximum.
Optimal foraging in plants:
If they need light they grow shoot and stems more. If they need nutrients they grow more roots.
Behavioral ecology
the study of social relations. are important because they often directly impact the reproductive contribution of individuals.
Fitness
the number of offspring or genes contributed by an individual to future generations.
Females vs males
larger more costly gametes vs smaller less costly gametes. reproduction limited by resources vs reproduction limited by female access.
Intrasexual selection
Individuals of one sex compete among themselves for mates.
Intersexual selection
members of one sex choose mates from the other sex based on particular traits.
John Endler
GUPPIED MAN. HE ENDED UP WITH GUPPIES. Pike Cichlid reduced coloration.
Kodric-Brown
Attractive and dominant guppies win!
Thornhill
Scorpions with dead crickets, spit or nothing?
Marshall
Wild Radishes: nonrandom mating was evident. diff fathers had higher seed levels, seed quality levels and positions.
eusociality
complex with more than 1 generation living together, cooperative care of young and division between sterile and reproductive classes.
Inclusive fitness
investing energy into genetically related individuals increases this fitness.
philopatry
tendency of some organisms to remain in the same area throughout their lives.
Ligons
Woodpecker: help young to one day inherit territory or to tend to half and full siblings. females with delayed reproduction had higher lifetime reproductive sucess
lifetime reproductive success
total number of offspring produced over the course of a lifetime.
comparative method
involves comparisons of the characteristics of diff species or populations of organisms in a way that attempts to isolate a particular variable or characteristic of interest such as sociality.
haplodiploidy
in this system males develop from unfertilized eggs and are haploid and females develop from fertilized eggs and are diploid.
Distribution
shape, size and location of a pop.
abundance
total number of individuals or biomass, of a species in a specific area.
distribution limits.
Fundamental vs realized niche.
environment limits the geographic distribution of species.
small scale vs large scale
small distances over which there is little environmental change significant to the organisms vs large scale where there is substantial change. small scale you can have clump, regular or random but on a large scale individuals are clumped.
Terry Root
Christmas bird count, shows clumping. hot spots.
population density vs organism size
density declines as organisms get bigger.
3 types of rarity:
Rarity 1: extensive range and habitat tolerance but small pop size. Rarity 2: extensive range and population but narrow habitat tolerance.
extreme: restricted range, narrow tolerance and small populations.
colonization cycle
interplay between downstream and upstream dispersal.
dispersal can increase or decrease local population densities.
yay
metapopulation
a group of subpopulations living in patches connected by limited individual exchange make up metapolulation.
cohort
group of individual born at the same time. can never get bigger.
cohort vs static life stable vs age distribution
group born a same time follow to death vs sample individuals born at different times, take each one’s death. age distribution is proportion of individuals of different ages within a pop.
types of survivorship curves
type 1: high old-age morality type 2: constant mortality type 3: high infant morality.
fecundity schedule
tabulation of birthrates for females of different ages.
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