BIOL 300: Exam 4, Module 16: Ecology

Module 16: Ecology

What is ecology?

A sub-discipline of biology that examines how living things interact with their environment

What is population ecology?

The study of how a population changes through time

Give an example of Population Ecology.

The study of all the squirrels in a park

What is community ecology?

The study of interactions between species

Give an example of Community Ecology.

How the squirrels in a park interact with the oak trees in the park, or how they interact with the ducks in the park, etc.

How does one species cause another species to change?

through interactions

What is an ecosystem?

All of the living things, non-living things and natural processes occurring in a specific area

What are the two main components of an ecosystem?

Biotic (living things in an area) and Abiotic (all of the non-living things in an area)

Give examples of Biotic components

Plants, animals, fungi, protists, bacteria & archaea

Give examples of Abiotic components

Rocks, wind, energy, water, minerals

List some Natural Processes important in ecosystems.

Cycles of nutrients such as carbon, nitrogen, and phosphorus; energy flow; erosion; decomposition

What is a Biome?

Large ecosystems with similar soil, rainfall, and temperature characteristics

List some examples of Biomes mentioned.

Temperate rainforest, Taiga, Temperate grassland, The Mojave Desert, Wetlands

Are microbes bad for us?

No

How does the microbial cloud influence us?

It helps develop the immune system, fights pathogens, helps our metabolism

What is a Niche?

An organism's specific role in its ecosystem

What is included in an organism's Niche?

Habitat, diet, predators, species competition, when it is active, specific abiotic requirements

Where does energy in a terrestrial ecosystem ultimately originate from?

the sun

what is a food web?

The feeding connections between organisms in an ecosystem

what is a Trophic Level?

The feeding level in a food web

What are Producers? Give an example

Organisms that convert solar energy into chemical energy, also convert CO2 into sugar. Examples: plants, bacteria, & protists

What are Primary Consumers? Give an example

Consumers (herbivores) that get their energy from eating (consuming) producers. Examples: deer, rabbits, mice

What are Secondary Consumers? Give an example

Consumers (carnivores) that eat primary consumers to get their energy. Examples: bobcats, weasels

What are Tertiary Consumers? Give an example

Consumers (carnivores) that eat secondary consumers to get their energy. Examples: bears, sharks, lions

What are Omnivores? Give an example

Organisms that eat both plants and animals. Examples: raccoons, black bears, orangutans, humans

What are Decomposers? Give an example

Organisms that feed on dead or decaying organic matter from any trophic level. Examples: fungi, insects, worms

State the "10% Rule" of energy transfer.

Only 10% of energy that enters one trophic level is passed on to the next trophic level

What are the three possibilities for how a population changes?

Grow, decline, stabilize

What determines how big or small a population is?

Biotic potential (maximum number offspring under ideal conditions) and Environmental resistance (things that decrease population size from its biotic potential, including: disease, competition, predators, and limited food)

What shape is the population growth curve under ideal conditions?

Exponential (J-curve)

What happens as populations reach their Carrying Capacity?

They will begin to exhibit logistic growth (S-curve) and stabilize

What are the three key kinds of interactions between species in Community Ecology?

Competition, predation, symbiosis

What is Competition?

Interaction when two organisms require the same resource in a community; they tend to fight over it

Name the three types of Symbiosis.

Commensalism, Mutualism, Parasitism

Describe Commensalism and give an example.

One species in the relationship benefits but the other is not affected positively or negatively. Example: orchid plants, cattle egret and cows

Describe Mutualism and give examples.

Both species benefit from the interaction. Examples: oxpeckers & rhinoceros, honeybees & flowers

Describe Parasitism and give examples.

One species benefits, and the other is harmed but doesn’t die. Usually parasites are species specific.

What are the two types of competition?

Intraspecific and Interspecific

Intraspecific Competition

Within the same species.

Generally minimzied by territoriality and ritual displays.

Interspecific Competition

Between different species.

Results in one specifies going extinct or both species remain at lower numbers.

Can also result in resource partitioning

Define resource partitioning

Two species adapt to sharing a resource.

What are the 5 ways that prey avoid being eaten? Give examples for each.

1. protection/armor (e.g. armadillo, thorny plants)

2. camouflage (stick bugs)

3. toxins / warning colors (coral snakes, monarch butterflies)

4. group together (meerkats, zebras)

5. being fast (gazelle)

How do predators find food?

They same way as prey!

what is the most common form of symbiosis?

parasitism

give an example of internal vs. external parasites

internal - tapeworm or heartworm

external - ticks, fleas