A Unit on Ecology

Portions of chapters 40-43

Health of a species, one population at a time

• The healthier each population is, the healthier the species is as a whole

• A healthy population– _______________– _______________– Birth and death rates

_________________and equal

Ch40

How do you characterize a population?• Size: number of individuals

___________________________________________(can be difficult… take into account that you cant catch everyone)

• Age Structure: pre-reproductive, reproductive, post-reproductive

• _____________: number of individuals per area (depends on the size of the area)

• Distribution: ______________ _______________throughout their area– ____________ in herds– Clumped near good

resources– Random/even (very rare)

ch40

Arrivals, departures and limits…

• Population size is affected by individuals who enter (immigration) and leave (emigration).

• Population size is ________ _______________________– Carrying capacity is the

maximum number an environment can sustain indefinitely… _________ ________________________________________________________________________________

ch40

Humans… defying all odds

• Everything that should limit population growth has been ‘beaten’ by humans– Resources… _____________

_______________________– Disease… _____________– Birth-rate, death-rate…

________________– Reproduction… ___________

• Our resources should eventually be limited by something… what will it be?

Ch40

Community: populations living together

• Combination of the living species in an area…

• Based on 5 factors1. ______________________2. Kinds and amount of

resources3. Adaptations/ niches of

individual species4. Species interactions (_____

_____________________________________________)

5. Pattern of population size (is a population growing, or waning)

Ch41

Interactions between species shape a community : symbiosis

• Symbiosis is a long standing interaction between two populations/ species… it can be:

• Mutualism: an interaction that _____________________(pollinator with a flower, lichen, anemone fish and anemone)

• ______________: an interaction were one member benefits and the other is hurt/harmed in some way. (tapeworms, ticks)

• Commensalism: an interaction where ___________________ ____________________________one way or another. (scavengers ‘cleaning up’ a lion kill, barnacles on attached to a whales' skin)

Ch41

Competition is an interaction too.

• Competition: the using of the same resources by multiple species… when one is successful, the other is not – Interference: _________________________

_______________________… blocking them from living there in the first place (aromatic compounds in plants)

– Exploitative: equal access ________________ ________________ at using it, so does better and the other leaves.

• Reactions/ results of competition– Competitive exclusion: Where nutrient

requirements overlap so greatly that the two species cannot coexist… _________________ _____________________________________

– Resource partitioning: Where similar resources are divided among lines that are not crossed… like fruit size, ___________________________ ______________________________________

Predator- Prey interactions

• Different than competition because it is necessary that the prey not leave altogether (____________________)

• __________________________________________________________________________________________________________________________________________________________________________________________

• If the predator doesn’t figure out a way/ evolve to counter the new feature they will die.

• If the number of prey rise, that increases food supply for predators,

• Predators increase as the food supply is available, causing a drop in prey, followed by predators

• Can include another factor… food for the prey

Prey Adaptations

• Prey adaptations: – _______________: hard to

spot (the kind depends on the keenness of the predators vision)

– Warning color: prey that defend themselves with poison advertise it so they will be skipped not eaten• _______________ where

certain species try to take on the color, without spending the energy on the toxin… smart!!

ch41

King Snake

Coral snake

Predator Adaptations

• Predator Adaptations:– _________________: learn

how to thwart the problem (find antidotes, or eat only the palatable portion)

– Burst of speed: __________ ______________________________________… they can’t be both. Or really fast and short bursts or kind of fast over longer bursts.

– __________________: to lay in wait for unsuspecting prey

Threats to communities/ diversity (Humans)

• Once communities have been established new species, human attack or disruption of habitat can quickly destroy what it took thousands of years to create.– Invasive species: ________

___________________________________________________________________________________________Unchecked these species grow out of control… killing everything in their path. (rabbits in Australia)

– Hunting/ Poaching– Habitat Loss and

_________________________

Ch 41/42

Endangered Species• Hunting and poaching: Humans

are predators and proud of it. Our ________________________________________________________– Black market poaching etc is

still a HUGE problem for the most endangered (__________ __________________________________________________)

• Habitat loss: even worse than hunting them is ______________. Most _______________________ ________________________________________________________. – As we move in, they move out…

when they get squished into small areas, they kill each other, or they try to come back and we kill them

How can we conserve and sustain current diversity

• Conservation Biology: think about the natural species before you build. ______________________________________________________________________________________________________________________

• Identifying at risk areas: _______________________________________ __________________________________(easier said than done)

• Work with new communities to preserve what at risk species require: – ____________________________… limit production, deforestation or

building to allow for the area to recover between attacks.

Ch 41/42

Everything is a cycle

• All matter and all energy are conserved… so _________________ ___________________________________________________________.

• _________ cycle… lake/ocean cloud rain river lake/ocean

• __________ Cycle… disruptions lead to global warming

• ___________ and _____________ also have cycles

ch42

Global warming• Too much production and not

enough absorption of carbon dioxide throws off the cycle

• ______________________________________________________________________________________________________________________

• This causes an increase of temperature over time, and the heating of the earth… which means melting polar ice caps

• We must stop the cycle… produce less CO2 and absorb more (with plants)

All the populations fit together into the biosphere

• Biosphere is the sum of all the planets ecosystems

• An ecosystem are all the biotic (living) and abiotic (nonliving) things in a certain area– The are generalized as ______

• Biomes have specific/ recognizable features– Salt water biomes: ocean (coral

reefs, wetlands, intertidal zones, deep ocean etc)

– Freshwater biomes: lakes, ponds, rivers, streams

– Terrestrial biomes: _________ ___________________________________________________________________________

Ch 43

Kinds of Terrestrial Biomes

Reflect the climate of the earth… • Tropical Forest: Constantly ____

_____________________, warm temperatures, 12 hour days. Tons of diversity and vegetation

• Savannas: Think Lion King. Lots of grass, grazing animals and their predators

• Deserts: __________________ ___________________… can be hot and dry, or cold and dry. Very little vegetation

Ch 34

More Biomes• Spiny Shrubs/Chaparral:

_______________________________________________. This is our usual vegetation

• Temperate grassland: prairies, depending on the location can have long or short grass (good soil!)

• Temperate deciduous forest: __________________, color changing, cold winters, hot summers

• Coniferous forest/ taiga: ______________, moderate summers

• Tundra: ________________