chapter 5

Question 1

Genetic diversity vs species diversity vs ecosystem diversity distinctions

Answer 1

Genetic diversity focuses on genetic differences within a species.
Species diversity is about the variety of species in an area.
Ecosystem diversity deals with the variety of different ecosystems in a region.

Question 2

Describe what is meant by background extinction rate. What is the background extinction rate? How does the background extinction rate compare to the current number of species estimated to be going extinct each year?

Answer 2

The background extinction rate is the rate at which species go extinct naturally without any external interference

The BER is supposed to be 1-5 species per million per year. Actual rate is somewhere between 100-1000 times that

Question 3

Explain how habitat loss affects specialist species compared to generalist species. Is it better to protect habitats or to try to save individual species? Explain your reasoning

Answer 3

Habitat loss is more devastating to specialist species who need highly specific environments to thrive. Conserving habitats is better (more cost effective, protects multiple species at once, prevents future extinctions, helps preserve the essential functions of ecosystems)

Question 4

Invasive species

Answer 4

Nonnative species that harm their new habitat
Characteristics:
- Rapid reproduction
- Lack of native predators or competitors
- Damages biodiversity/functioning of new ecosystem

Examples:
- English Ivy
- Zebra mussel
- Kudzu (vine that ate the south)

Question 5

Indicator species

Answer 5

Species that can indicate the health of an ecosystem via their presence/absence/health

Characteristics
- sensitive to environmental change
- Can indicate environmental health
- Often used in conservation efforts

Examples
- Lichens sensitive to air pollution
- Amphibians sensitive to changes in water quality and air quality - multipurpose indicator
- Mayfly Nymphs - Their presence in rivers indicates good water quality, while their absence suggests pollution.

Question 6

Foundation species

Answer 6

Species that play pivotal roles in establishing/shaping ecosystems by creating habitats

Characteristics
- They have a significant impact on ecosystem structure and biodiversity.
- Provide essential resources (e.g., food, shelter) for other species.
- Often serve as habitat providers or primary producers in ecosystems.

Examples:
- Coral
- Oak trees
- Beavers (make dams)

Question 6

Endangered species

Answer 6

Species that have a very high risk of going extinct

Characteristics
- Very small populations in the wild
- Limited geographic range/population size
- Often subject to very intense conservation efforts

Examples
- tiger
- blue whale
- sea otter

Question 7

Threatened species

Answer 7

Species that will likely become endangered but are not quite endangered

Characteristics
- declining population but not quite critically low yet
- conservation efforts needed to prevent future decline
- often struggle with similar things to endangered species (habitat loss, overexploitation, etc)

Examples:
- snow leapord
- african elephant
- bald eagle

Question 8

Endemic species

Answer 8

Species only found in certain parts of the world

Characteristics
- limited geographic range
- very vulnerable to extinction due to limited geographic range
- adapted/dependent on unique habitats

Examples:
- kakapo
- galapagos turtle
- redwoods

Question 9

Why do many islands possess endemic and specialist species? How would invasive species threaten the survival of endemic species on islands?

Answer 9

Due to geographic isolation preventing migration, lack of competitors native to the island

Invasive species can create unforeseen competition for resources/outcompete native endemic species
Introduce diseases, predation, etc

Question 10

Species richness vs species evenness

Answer 10

Richness - raw # of species, not regarding how many of each
Evenness - balance between species

Question 11

What is a phylogenetic tree? What do these diagrams help us understand? Draw an example of a phylogenetic tree.

Answer 11

Evolutionary tree, demonstrates how diff species evolved from each other

Uses
- helps us understand common ancestors, speciation, help with comparitive biology to identify potential similarities

Question 12

Describe what is meant by the “bottleneck effect” (population bottleneck). What effect does a population bottleneck have on the genetic diversity of a species? Explain with an example.

Answer 12

Sharp reduction in population size due to an environmental or human-caused incident, associated with steep reduction in genetic diversity and increased risk of inbreeding

Cheetahs are genetically super similar, have high rates of infertility and other issues associated w low genetic diversity

Question 13

What is the founder effect + an example explaining impact on genetic diversity

Answer 13

The founder effect refers to a loss of genetic variation that occurs when a small group of individuals establishes a new population in an isolated location.
For ex –
The amish have a really high rate of a particular kind of dwarfism

Question 14

What defines a mass extinction? According to the fossil record, how mass extinctions have previously occurred on Earth? Make a list of the 5 mass extinctions, state when each occurred and what scientists think caused the extinctions.

Answer 14

3 things that define a mass extinction
- widespread loss of species
- global impact
- impact across diff groups of animals

I’m giving up on remembering the mass extinctions unfortunately we will be cutting our losses

Question 15

What data suggests that the sixth mass extinction is currently taking place? What is causing the sixth mass extinction?

Answer 15

Data:
- Abormally high extinction rate compared to backg
- widespread declines in biodiversity
- observable impacts on ecosystems and species.

Primarily caused by various human activities (overexploitation, overfishing/hunting, habitat destruction, urbanization, wtv else)

Question 16

What is causing global declines in the genetic diversity of domesticated species (species grown for food, crops, livestock, etc.)? What are people doing in order to try to preserve genetic diversity in domestic species?

Answer 16

Causes:
- monoculture farming, growing only one thing in one large area reduces genetic diversity
- selective breeding for desirable traits reduces genetic diversity
- pesticide and herbiside usage leads to the survival of only a few genetically similar varieties that r resistant
- globalization has led to survival of the fittest

solutions:
- crossbreeding to create new varieties out of existing ones
- diversifying farmland by planting may diverse crops together
- legal protections regulating GMOs

Question 17

Define the IUCN (International Union for Conservation of Nature) categories: extinct, endangered, threatened, near-threatened, and least-concern species.

Answer 17

Extinct: A species is considered extinct when there is no reasonable doubt that the last individual has died.

Endangered: Very likely to go extinct soon in the wild

Threatened: Not quite endangered, but could become endangered if nothing changes

Near threatened: could become threatened in the near future

Least concern: healthy, abundant populations

Question 18

For each of the following groups of organisms, list the percentage of each that are considered threatened, near-threatened, and least concern.
Conifers; birds; reptiles; mammals; amphibians; and fish

Which category of organisms has the most threatened species and is experiencing the greatest global declines? Why would this group have the most vulnerable number of species?

Answer 18

Among the groups listed, amphibians have the highest percentage of species that are considered threatened (41%). They are experiencing the greatest global declines among these groups.

Reasons why
- permeable skin, sensitivity to external conditions
- habitat loss (impacted by both aquatic and terrestrial)
- highly suspeptible to disease and polllution

Question 19

Provisioning

Answer 19

Getting food/resources from ecosystems (like food via fishing/gathering and fresh water from lakes)
Disrupted by deforestation, reducing the output of forests and water pollution

Question 20

Regulating

Answer 20

Climate regulation (bodies of water keep temp steadier) and pollination.
Pesticide usage harms pollinators and excess carbon emissions prevent bodies of water from effectively regulating temps

Question 21

Cultural

Answer 21

Non-material benefits like hiking trails and aesthetic value
Urbanization and pollution disrupt natural beauty

Question 22

Supporting

Answer 22

Processes that support other ecosystem services like soil formation and nutrient cycling (harmed by industrial agricultural practices which disrupt natural decomposers/soil formation)

Question 23

IUCN

Answer 23

Establishes red list to identify urgent need for conservation efforts, spearheads some field conservation programs

Question 24

CITES

Answer 24

International treaty focused on regulating international trade of wildlife and ensuring that it does not cause harm to them. Allows for certain animals to be classified as protected and creates a system for global enforcement of wildlife trafficking laws

Question 25

Convention on Biological Diversity (CBD)

Answer 25

International treaty attempting to preserve biodiversity by setting national goals and action plans and promoting sustainable usage

Question 26

Lacey Act

Answer 26

U.S. law that prohibits trafficking in illegal wildlife, fish, and plants.

Question 27

The Marine Mammal Protection Act

Answer 27

The MMPA is a U.S. law that prohibits the "take" (hunting, capturing, or killing) of marine mammals in U.S. waters and by U.S. citizens, with limited exceptions.

Question 28

Endangered Species Act (ESA)

Answer 28

U.S. law that provides for the protection of species at risk of extinction and the preservation of their habitats. Protects endangered species and their habitats. Creates recovery plans

Question 29

Debt for Nature

Answer 29

Program where a portion of a country's foreign debt is forgiven in exchange for the country's commitment to invest in conservation projects and biodiversity protection. Creates a financial incentive to meet climate goals and creates funding for conservation efforts elsewhere

Question 30

When protecting areas of land or water as nature preserves, describe how the size, shape, and connectedness of the protected area are important factors to consider.

Answer 30

Size - larger areas can support more species/individuals however due to land-use restrictions and funding, it can be harder to protect large areas. Also larger area = more diversity = reduced extinction risks Shape - more compact, less fragmented territories result in reduced edge effect, allowing for more undisturbed space in the middle of the reserve. sometimes irregular shapes are necessary due to geographic features Connectedness - corridors allow gene flow and boost resiliance to climate change/other external changes. Human activity (roads, etc) might necessitate fragmentation.

Question 31

What is “edge habitat”? Why does the amount of edge habitat matter when planning protected habitats?

Answer 31

Edge habits have diff species than interior (ones that thrive in disturbed areas) and usually are not good for internal species which require more stability/space. Edge habits are more vulnerable to external changes and invasive species

Question 32

Describe biosphere reserves. Which three zones should be considered when planning biosphere reserves? Describe the importance of these zones.

Answer 32

They maintain biodiversity while fostering sustainable livelihoods for local communities. Biosphere reserves are meant to act as living laboratories, where scientists can study ecosystems, human impact on the environment, and sustainable resource management practices. Three zones -- core zone, strictly for conservation and research efforts, buffer zone with reduced human activity that supports ecosystem development and transition zone with more human activity sustainable land-use practices, integrates conservation with community development, and generates economic benefits.