apes

APES

Chapter 5: Species Interactions & Community Ecology

Group Work:

• In individual groups, look at each slide and determine what it represents

• Write your answers down• As a class we will go over each slide and

discuss answers

Resource Partitioning:Each Bird Uses the Tree for Food, However…They Each Divide up Different Portions of the Trunk

Predator/Prey Paired Cycles: One Increases, Causing the Other to Decrease, and Vice Versa

Trophic Levels: The Way in Which Energy Moves Thru Systems

Lower Level Org. Generally Contain More Energy, and Are in Greater Numbers-

Food Web

KeyStone Species Keep Ecosystems in Check- Sea Otters are the Keystone Species in This Environment

Activity:

• Read the “Inferring Zebra Mussels’ Impacts on Fish Communities”

• Answer Question #5 page 113, Seeking Solutions.

Case Study: black and white and spread all over

• In 1988, Zebra mussels were accidentally introduced to Lake St. Clair– In discharged ballast water

• By 2010, they had invaded 30 states– No natural predators,

competitors, or parasites• They cause millions of dollars

of damage to property each year

Lets Begin ;)

• List some Non-natives to Florida– Brazilian Pepper– Melalucca– Cuban Tree Frogs– Lion Fish

• Now List Some Threats They Pose to Florida– No predators so they take over environments– Eat all the native species (Cuban tree frog, Lion

Fish)

Rap Time: Zebra Mussels

• From your reading, where are they located?– Great Lakes

• Do you think they are located anywhere else in the US?– They are here in Florida!– University of Florida News – Discovery Of Invasive

Zebra Mussel Prompts Warning From State Officials– Green Mussels in Florida– Green Mussels

Problems here in Florida

• Same as in other places– Clog pipes– No predators– No competition– Damage boat engines– FILTRATION OF PHYTOPLANKTON!!!

• Takes food from native organisms– Starves them out

» Specifically ZOOPLANKTON

Lion Fish

http://www.reef.org/reef_files/Lionfish%20quickfacts.pdf

After reading the fact sheet, what do you know about this critter?Use knowledge learned from the last chapter (generalist or specialist, K or r species, what is the outlook for the native populations, how did it get here, why is it still here, discuss the evolution of the fish, etc.)

Activity:

• H/W: Go home tonight and find at least 2 more non-native invasive species (plant or animal). Include:– Generalist or specialist– K or r species– What is their main source of food– Any predators– Short synapses of how they are affecting Florida– Must be typed!! 12 point font, double spacced, times

new roman or arial please ;)

Video Clip

• Welcome to Discovery Education Player

Species Interactions• 5 Major Types of Interactions Among Species

– Competition• When organisms are seeking same limited resource(s)

– Predation• When one organism (predator) eats another (prey)

– Parasitism• One organism benefits, the other is harmed

– Herbivory• An organism feeds on plant material

– Mutualism• Both organisms benefit from the relationship

Competition• Interspecific:

– Among members of 2 or more DIFFERENT species (cardinals and blue jays)

• If one is more effective– Wipe-out competitor altogether

• Through evolutionary time, co-existance is also possible– Timing events, slightly different food sources, etc.

» RESOURCE PARTITIONING

• Intraspecific:– Among member of the SAME species

• Cardinals

• All competition events have a negative impact

Results of interspecific competition

• Competitive exclusion = one species completely excludes another species from using the resource– Zebra mussels displaced native mussels in the Great

Lakes

• Species coexistence = neither species fully excludes the other from resources, so both live side by side– This produces a stable point of equilibrium, with stable

population sizes– Species minimize competition by using only a part of the

available resource (niche)

© 2011 Pearson Education, Inc.

Niche: an individual’s ecological role

• Fundamental niche = the full niche of a species

• Realized niche = the portion of the fundamental niche that is actually filled

- Due to competition or other species’ interactions


Resource partitioning

• Resource partitioning = species use different resources

- Or they use shared resources in different ways

- Ex: one species is active at night, another in the day

- Ex: one species eats small seeds, another eats large seeds


Character displacement

• Character displacement = competing species diverge in their physical characteristics

- Due to the evolution of traits best suited to the resources they use

- Results from resource partitioning

• Birds that eat larger seeds evolve larger bills

- Birds that eat smaller seeds evolve smaller bills

Competition is reduced when two species become more different

Predation:

• Predator/Prey relationships• Predation can drive population dynamics

– Increase in predators will…..– Increase in prey will ………

• These events can cycle throughout time

• Predation can also drive evolution– Stronger adaptations become selected for– Defense mechanisms become selected for


Zebra mussel predation on phytoplankton

• Zebra mussels eat phytoplankton and zooplankton

- Both populations decrease in lakes with zebra mussels

• Zebra mussels don’t eat cyanobacteria

- Population increases in lakes with zebra mussels

• Zebra mussels are becoming prey for some North American predators:

- Diving ducks, muskrats, crayfish, flounder, sturgeon, eels, carp, and freshwater drum


Defenses against being eaten

Parasites• Relationships in which 1 organism depends on another,

while doing harm– USUALLY does not result in death. Why not?

• Most live inside their host– Disease pathogens (ex; protist that causes malaria)– Animals (tapeworms)

• Some live externally– Lamprey

• Parasitoids– Eggs are laid on the backs of others, when they hatch, use host as

food source

Co-evolution

• Parasites will adapt and evolve with changes in host– Evolutionary Arms Race

• Host changes in order to adapt to parasite pressures• Parasites will change in order to adapt to host

pressures

Herbivore• When animals feed on the tissues of plants

– Insects are most wide-spread– Doesn’t usually kill plant, but can affect growth

and reproduction

• Plants have also evolved to defend themselves– Chemically– Arm themselves w/thorns, spines, or hairs– Critter usually evolves as well, tho

• Evolutionary Arms Race

Mutualist

• Interacting species benefit from one another– Each provides a service or resource the other needs

• Symbiosis: two organisms live in close physical contact– Not always the case however;

» Pollination; physical contact may only happen once

Commensalism• One species benefits from relationship while the

other is neither harmed nor benefits– Cattle Egret: benefits from cattle stirring up insects,

cow is neither harmed nor really benefits

• Amensalistic: hard to prove- One organism harms or inhibits another while remaining unaffected itself;– Fungus Penicillium notatum which produces penicillin-

the penicillin inhibits growth of bacteria, but it appears that the Penicillium is unaffected

Activity• Questions 1 &2; Testing Your Comprehension• Seeking Solutions #1

Ecological Communities• Community Ecologist:

– studies the way in which species co-exist – how they relate to one another – how communities change thru time– why patterns exist

• Most important of these relationships is – Who eats whom!!

• Organisms feed on one another, energy moves from one level to the next

– Trophic Level


Energy passes through trophic levels

• One of the most important species interactions

- Who eats whom?

• Matter and energy move through the community

• Trophic levels = rank in the feeding hierarchy

- Producers (autotrophs)

- Consumers

- Detritivores and decomposers

3 Major Trophic Levels

• Producer– Autotrophs; self feeders- green plants, algaes,

cyanobacteria capture solar energy or chemical energy and use photosynthesis or chemosynthesis to produce sugars

• Consumer– Primary Consumers; eat producers– Secondary Consumers; prey on primary consumers– Tertiary Consumers; usually top of food chain

Continued

• Detritivores/Decomposers; consumes non-living organic matter– Detritivores- scavenge waste products or dead

bodies (consume non-living organic matter)• Millipedes, soil insects, vultures, hyenas

– Decomposers- break down leaf litter and other non-living matter into simple constituents to be taken up by plants (absorb nutrients from non-living organic matter)

• Bacteria, fungi

10% RuleEnergy Decreases @ Higher Levels

• Most energy organisms use is lost thru respiration as heat

• Only small amounts of E is transferred from 1 level to the next– 10% rule; ~10% of initial energy moves to next level

• This means that there is many more grasshoppers reqd to sustain bird pop. Etc.

• VEGETARIANS HAVE SMALLER ECOLOGICAL FOOTPRINTS!!

Food Web vs Food Chain

• Food Chain: simple representation of energy mvmt:

Food Web vs Food Chain

• Food Web: much more realistic representation of how energy moves thru systems-

Roles are NOT the same

• Keystone Species: species with strong or wide-reaching impact far out of proportion to its abundance – Removal of this species will have substantial ripple

effects– Can alter large portions of food webs

• Usually large-bodied 2nd ary or tertiary consumers near the top of food chain

• Controls herbivores, who if left unchecked can devastate ecosystems

Some organisms play big roles


Species can change communities

• Trophic Cascade = predators at high trophic levels indirectly affect populations at low trophic levels

- By keeping species at intermediate trophic levels in check

- Extermination of wolves led to increased deer populations, which overgrazed vegetation and changed forest structure

• Ecosystem engineers = physically modify the environment

- Beaver dams, prairie dogs, ants, zebra mussels


H/W

• Read Article: Urchins, Otters, and Whales

• Answer questions

- Please Type Assignment!!

- 12 pt font, double spaced, Times New Roman or Aerial

• Due Monday, 10/22/12

H/W; Using Question #2 of Seeking Solutions as a Guide, Design an Intricate Food Web (on the front) vs Food Chain (on the back) on Poster Board. This is an Exam Grade, and MUST be turned into me by Wednesday of next week!!

(10/24/12)Keep track of your data with photographsBe creative; make sure you use your terminology for each organism (producer, tertiary consumer, etc)

Communities Response

APESChapter 5

Disturbances

• What is a disturbance?– Flood– Avalanche– Human impact

• Communities are dynamic and can respond by:– Resisting change and remaining stable = Resistance

• It may later return to original state showing Resilience

– Become permanently modified and never return to original state

Succession Follows Disturbance• Disturbance eliminates all or most species, effected site

will undergo predictable changes– Primary Succession: not even soil remains after disturbance;

new biotic community must be built from scratch• Glaciers retreat, lakes dry up, volcano errupts

– First colonizers = Pioneer Species; » Lichen; breakdown rock creating substrate for plants, etc.

– Secondary Succession: Does not destroy all life or soil, leaving some biota behind to repopulate

• Fire, hurricane, logging, farming, etc. – Pioneer species come in, usually weeds, and eventually new landscape arises

• Succession leads to Climax Community


Communities may undergo shifts

• The dynamics of community change are more variable and less predictable than thought

- Conditions at one stage may promote another stage

- Competition may inhibit progression to another stage

- Chance factors also affect changes

• Phase (regime) shift = the overall character of the community fundamentally changes

- Some crucial threshold is passed, a keystone species is lost, or an exotic species invades

- i.e. overfishing and depletion of fish and turtles has allowed algae to dominate corals


Community cohesion

• Frederick Clements = viewed communities as cohesive entities, with integrated parts

- Its members remain associated over space and time

- The community shared similar limiting factors and evolutionary histories

• Henry Gleason = maintained that each species responds independently to its own limiting factors

- Species join or leave communities without greatly altering the community’s composition

- The most widely accepted view of ecologists today


Invasive species threaten stability

• Invasive species = non-native (exotic) organisms that spread widely and become dominant in a community

- Introduced deliberately or accidentally from elsewhere

- Growth-limiting factors (predators, disease, competitors, etc.) are removed or absent

- They have major ecological effects

- Chestnut blight from Asia wiped out American chestnut trees

• Some species help people (i.e., European honeybees)


Two invasive mussels


Controlling invasive species

• Techniques to control invasive species

- Removing them manually

- Applying toxic chemicals

- Drying them out

- Depriving them of oxygen

- Stressing them with heat, sound, electricity, carbon dioxide, or ultraviolet light

• Control and eradication are hard and expensive

Prevention, rather than control, is the best policy


Altered communities can be restored

• Humans have dramatically changed ecological systems

- Severely degraded systems cease to function

• Ecological restoration = efforts to restore communities

• Restoration is informed by restoration ecology = the science of restoring an area to an earlier condition

- To restore the system’s functionality (i.e. filtering of water by a wetland)

- It is difficult, time-consuming, and expensive

• It is best to protect natural systems from degradation in the first place


Restoration efforts

• Prairie restoration = replanting native species, controlling invasive species

• The world’s largest project = Florida Everglades

- Flood control and irrigation removed water

- Populations of wading birds dropped 90-95%

- It will take 30 yearsand billions of dollars to restore natural water flow

Biomes

• Activity: • Monday and Tuesday in the 3rd Floor

Computer Lab: Rm 314– 12 Different Biomes– 11 Students – Present next week for an exam grade

apes

Documents

different species cardinals

native species cuban

different food sources

zebra musselsfrom

organism predator

different portions

native organismsstarves

native populations