BIO 111 - Chapter 45 & 47: Population & Community Ecology / Conservation Biology and Biodiversity / Climate Change

What is exponential growth? 

Rapid population increase where growth keeps speeding up over time

What is carrying capacity? 

The maximum number of individuals an environment can support

What is an ecological niche? 

A species' role in its environment—how it survives, eats, and interacts

What is species diversity? 

The variety and number of different species in a habitat or ecosystem

What is a habitat? 

The natural home or environment where an organism lives

What is habitat heterogeneity? 

When a habitat has many different features (e.g., trees, water, rocks), supporting more species

What is a keystone species? 

A species that has a huge impact on its ecosystem—even if not the most common

What is carbon sequestration? 

The process of capturing and storing carbon from the atmosphere (often by plants or soil)

What is a carbon sink? 

A natural system (like forests or oceans) that absorbs more carbon than it releases

What is a seed vault? 

A storage site that preserves seeds from many plants for future use, like a backup

What are the levels of biological organization?

1. Organism: A single living thing. 

2. Population: A group of the same species living in one area. 

3. Community: All living organisms in one area. 

4. Ecosystem: All living and non-living things in an area. 

5. Biome: Large regions with similar climate and life (e.g., desert, rainforest). 

6. Biosphere: The entire part of Earth where life exists. 

How does loss of biodiversity affect human health, agriculture, and wild food sources?

• Human Health: Fewer plants/animals = fewer medicines and more disease spread.

• Agriculture: Less crop variety = more risk of pests and disease.

• Wild Food Sources: Fewer species = less seafood, game, and edible plants.

What are “regenerative benefits of a natural environment”?

Nature helps heal ecosystems and people by reducing stress, cleaning air/water, and restoring soil and wildlife.

What caused the Irish potato famine and how is it linked to biodiversity?

All potatoes were genetically the same, so when a disease hit, it wiped them out, showing why genetic diversity is crucial for survival.

What is the significance of “colony collapse disorder” in bees?

• Bees suddenly disappear from hives, hurting pollination and threatening food crops that rely on them.

How do habitat loss, overharvesting, and invasive species harm biodiversity?

• Habitat Loss: Destroys homes for plants and animals.

• Overharvesting: Removes species faster than they can reproduce.

• Invasive Species: Outcompete or kill native species.

What’s the relationship between the triton trumpet and the crown-of-thorns starfish?

• Triton trumpet eats crown-of-thorns, which eat coral.

• Overharvesting the triton led to starfish overgrowth and coral damage.

How do invasive species harm the environment and native species?

They take over, eat or compete with native species, and disrupt ecosystems.

What are greenhouse gases?

Gases like CO₂, methane, and water vapor that trap heat in Earth’s atmosphere, causing global warming.

What are anthropogenic (man-made) greenhouse gases?

Greenhouse gases produced by human activity, like CO₂, methane, nitrous oxide, and fluorinated gases.

What are the sources of these man-made gases?

• CO₂: Burning fossil fuels, deforestation

• Methane: Landfills, livestock (cow burps), oil/gas leaks

• Nitrous Oxide: Fertilizers, sewage, industrial processes

• Fluorinated Gases: Refrigerators, air conditioners, industry

Explain the greenhouse effect and how it warms Earth’s atmosphere?

Sunlight hits Earth → Earth reflects some, absorbs the rest → Heat gets trapped by greenhouse gases → Warms the planet, like a blanket.

What % of greenhouse gas emissions is from each gas?

• Carbon dioxide (CO₂): ~76%

• Methane (CH₄): ~16%

• Nitrous oxide (N₂O): ~6%

• Fluorinated gases: ~2%

What are 4 natural sources of carbon dioxide?

• Volcanic eruptions

• Respiration (breathing)

• Decomposition

• Ocean release

What are fossil fuels (coal, oil, natural gas) and how were they formed?

Energy sources from ancient plants and animals, buried and compressed over millions of years underground.

What are the top 4 uses of fossil fuels?

1. Electricity generation

2. Transportation (cars, planes)

3. Heating homes/buildings

4. Industrial processes (factories, plastic, cement)

Name four carbon sinks.

• Forests

• Soil

• Oceans

• Wetlands

What is plankton & how does it function in ecosystems?

Tiny drifting organisms that float in water. They start the food chain and help cycle nutrients and carbon.

What’s the difference between phytoplankton and zooplankton?

• Phytoplankton: Plant-like, do photosynthesis

• Zooplankton: Animal-like, eat phytoplankton

Define and give examples of ecological services.

Ecological services are benefits nature provides to humans.
Examples:

• Pollination (bees help grow food)

• Water purification (wetlands filter water)

• Air quality (trees absorb CO₂)

• Soil fertility (decomposers break down waste)

• Climate regulation (forests and oceans store carbon)

How does an invasive species like Eurasian milfoil interfere with ecological services?

Eurasian milfoil chokes waterways, blocks sunlight, kills native plants, and reduces oxygen in water. This disrupts fish habitats, hurts biodiversity, and damages recreational water use (like boating or fishing).

In what ways can invasive species impact the economy of a human population?

• Crop damage = less food, higher prices

• Fishing industry loss = fewer fish from destroyed habitats

• Water system clogs = costly maintenance

• Tourism drop = dirty or unusable lakes/rivers

How would the global mean temperature be affected if the Earth had no atmosphere?

It would be much colder, around -18°C (0°F) instead of 15°C (59°F) today. The atmosphere traps heat, keeping Earth livable.

How does an increase in the global mean temperature impact (Ocean Currents, Polar Ice Caps, Sea Level, Coastal Ecosystems, Food Production, Human Health)?

• Ocean Currents: Warmer water changes flow, disrupting weather (e.g., hurricanes, El Niño).

• Polar Ice Caps: Melting raises sea levels and destroys polar habitats.

• Sea Level: Rises due to melting ice + warm water expanding.

• Coastal Ecosystems: Saltwater floods wetlands, kills plants and animals.

• Food Production: Droughts, floods, heat waves reduce crop yields.

• Human Health: Heat waves, disease spread (like malaria), air quality issues.

What is the current world mean temperature?

59 F

How much has the world mean temperature risen since 1880?

1.4 - 1.9 F

How much lower was the mean temperature during the last ice age (when NY was covered in ice)?

10-11 F lower

How thick was the ice sheet over New York?

Up to 2 miles (3.2 km) thick

Discuss the major impacts of global warming.

• Rising sea levels → flooding cities

• Extreme weather → stronger storms, heat waves

• Loss of biodiversity → extinction of species

• Food and water insecurity → droughts, failed crops

• Climate refugees → people forced to move

• Health risks → disease spread, heat stress

How much would sea level rise if the Greenland ice sheet were to melt?

23 feet

What gases make up climate change & how much do they contribute?

• Carbon dioxide (CO₂) – ~78%

• Methane (CH₄) – ~21%

• Nitrous oxide (N₂O) – ~6%

• Fluorinated gases – ~2%

• water vapor - 2%

How is weather different from climate?

• Weather = short-term (day-to-day) changes in temperature, rain, wind, etc.

• Climate = long-term patterns of weather in a region (over decades or more).

What happens without greenhouse gases?

Earth’s surface would average around -18°C (0°F) — too cold to support life as we know it.
Greenhouse gases trap heat, keeping the planet warm enough to survive.

How long does carbon dioxide (CO₂) remain in the atmosphere?

300-1000 years

Name three natural sources of methane:

• Wetlands (like swamps)

• Termites

• Oceans

Name three human sources of methane:

• Livestock digestion (cow burps, mostly)

• Landfills

• Oil and natural gas drilling/leaks

How much is methane responsible for the global mean temperature increase since 1880?

15-45%

How many more times potent is methane than carbon dioxide & how long does it stay in the atmosphere?

80x more & about 20 years

What is sulfur hexafluoride (SF₆)?

What is more potent and longer lasting than CO₂ and CH₄?

How long does SF₆ remain in the atmosphere?

What are some nonrenewable energy resources?

What are some renewable energy resources?

What is the most used nonrenewable energy resource?

How much is the average global temperature projected to be by 2050?

How much is the average global temperature projected to be by 2100?

2.7 F

2-4 F

Name about 5 changes in habitat that can occur to both plant (flora) and widllife (fauna) due to extreme changes in temperature globally? 

• Loss of sea ice affecting polar species

• Shifting vegetation zones (tundra → forest, etc.)

• Coral bleaching

• Droughts affecting wetlands

• Species migration/displacement or extinction

Name about 3 changes in forestry and agricultural practices that can occur due to extreme changes in temperature globally? 

• Crop failures from drought, heat stress

• Shifts in growing zones (longer/shorter seasons)

• Increased pests/disease due to warmer temps

Name about 3 changes that can occur in weather patterns due to extreme changes in temperature globally? 

• More frequent/intense storms

• Longer heatwaves and droughts

• Heavier rainfall and flooding events

Name about 2 mitigation efforts to responding to climate change? 

• Reducing greenhouse gas emissions (e.g., transitioning to renewable energy)

• Carbon sequestration (e.g., planting trees, protecting forests, soil management)