ESS Topic 3

define species diversity + how it is measured

the diversity of species in a given unit of area for a given unit of time
1. species richness - # of different species in an area

2. species evenness - relative abundance of each species (measured w/ simpsons index)

define habitat diversity

Range of different habitats and ecosystems within a specific area ; supports a wider variety of niches and species that are adapted to its conditions

define genetic diversity + provide 2 examples of high and low genetic diversity

genetic variation within species ; improves species resilience + adaptability for long term survival

low diversity - cheetahs are genetically similar = vulnerable to disease and lacks ability to adapt which threatens long term survival

high diversity - coral = able to survive under many different conditions

how to use simpson’s index

D = N(N-1) / totaln(n-1)

N=total # of organizations in all species

n = # of individuals of a particular species

higher number = greater # of species + more even distributions of individuals among species
low number = a few species dominate the habitat = lower diversity

identify reasons why biodiversity is important for the ecosystem

1. provides ecosystem services

   1. pollination for crop production + wild plants

2. water purification

3. soil fertility

identify reasons why biodiversity is important for humans

1. food

2. medicine / herbal remedies

3. climate regulations

explain the connection between biodiversity and ecosystem resilience

• Genetic diversity: Allows populations to adapt to changes (e.g., climate shifts, disease).

• Species diversity: More species in a system = more roles (e.g., predators, decomposers, pollinators) = greater stability.

Habitat diversity: Different habitats support different species, leading to niche specialization and greater resilience.

a loss at any level can lead to the destabilization of an ecosystem and make them more vulnerable

list ways in which humans can impact biodiversity

1. deforestation

   1. reduces habitat + species diversity

2. positive impact

   1. rewilding can restore natural balance + enhance resilience

define evolution

the process by which species change over time through natural selection, mutation, genetic drift, gene flow

explain three key processes in evolution

natural selection - traits that increase survival become more common in a population

mutation - random changes in DNA lead to genetic variation

speciation - species isolation leads to evolution into a different species (can change organisms so much they can no longer breed with the original species)

explain the key mechanisms of natural selection with examples

1. genetic variation - every species had individuals with different characteristics

2. survival - certain traits give individuals an advantage in survival, especially when resources are limited (i.e pepper moths)

3. reproduction - longer survival = more likely to reproduce

inheritance - survivors pass their advantageous traits to their offspring

example:

rock pocket mice - genetically mutated to have darker fur (since they lived in a lava flow area) in order to hide from predators

peppered moth - soot pollution led to dark coloration = less likely to be seen by predators and caused a genetic mutation

identify some natural hazards and how they impact biodiversity

• earthquakes

• volcanic eruptions

• floods

• droughts

• tsunami

• hurricane/cyclones

• wildfires

impact biodiversity via

• ecosystem destruction

• infrastructure destruction

• loss of life

• economic impact

describe direct threats to biodiversity

1. overharvesting - unsustainable extraction of resources (e.g. overfishing + logging)

2. poaching - illegal hunting of wildlife for commercial purposes

3. illegal pet trade - capture + sale of wild species as pets

4. invasive species

describe indirect threats to biodiversity

1. climate change - alters ecosystems, shifts species habitats, increases stress on wildlife

2. pollution - contaminants damage ecosystems = affecting species survival + health

3. weak governance - poor regulation = illegal activities

define invasive species

non native organisms introduced to a new ecosystem intentionally or unintentionally by humans

explain 5 of the impacts that invasive species have on ecosystems

1. competition for resources - outcompete native species for resources

2. predation - invasive species can prey on native species that have no defense mech

3. introduction of disease - bring disease + parasites to native species

4. habitat alteration - changing physical ecosystem to make it less suitable for native species

5. hybridization - breeding w/ local species lead to changes in genetic makeup

describe pathways of introduction for invasive species

1. trade + transport - transported via ballast water, ships, cargo

2. agriculture - introduced intentionally for agricultural reasons but later escape into the wild

3. pet + wildlife trade - exotic pets released into the wild

4. tourism + recreation - unintentional transport of seeds, spores, small organisms

describe the economic and environmental consequences of invasive species

1. damage costs - agriculture, forestry, fisheries, water systems

2. displacement of native species - altering food webs, disrupting ecological processes, reducing ecosystem services

3. introduction of human disease - directly impact human health

list the 3 criteria for the IUCN red list

1. population size - smaller populations = higher risk of extinction

2. rate of population decline

3. geographic range - species w/ restricted range = more vulnerable to habitat destruction

provide an case study example of an invasive species

cane toads in Australia

• was introduced to combat cane beetles from sugarcane farms

• ended up becoming an invasive species due to its poisonous nature, rapid population growth, large prey range and ability to disrupt the food chain

solutions

• humane chemical sprays

• heavy reliance on citizen science to distinguish native frogs from cane toads

• removal of eggs

• predator training

identify potential arguments for conserving species/habitats

• aesthetic - enhances human well being, inspires art, beauty + appeal

• economic - ecotourism, provides resources

• ecological - role in ecosystem services

• ethical - moral responsibility to protect nature

• sociocultural - recreation/cultural opportunities

outline the 2 types of conservation strategies

1. In situ conservation/habitat - preserving species within their natural habitats.

2. Ex situ conservation/species - protecting species by outside of their natural habitats

evaluate the advantages/disadvantages of ex situ conservation strategies

advantages

• controlled environment

• supports breeding programs

• can save species on the brink of extinction

• preserves genetic diversity

disadvantages

• does not maintain natural behaviours/ecosystem roles

• expensive to maintain

• limited genetic diversity

• less focus on holistic ecosystems

evaluate the advantages/disadvantages of in situ conservation strategies

advantages

• preserves species in natural habitats

• maintains ecological interactions

• protects entire ecosystem + services

• allows for natural evolution + adaptation

disadvantages

• vulnerable to external threats (e.g. poaching, habitat destruction)

• requires large areas ; can conflict w/ human activity

• difficult to manage in highly disturbed areas

• limited envur

define flagship species

charismatic species selected to appeal to the public and help protect other species in an area ; usually popular, recognized, large and furry and used as symbols for conservation efforts

outline the importance of mixing ex and in situ conservation strategies with examples

can protect species in the short term while working towards long term ecosystem restoration

usually focuses on a keystone or flagship species

e.g. Chengdu Giant Panda base uses mixed conservation strategies

• breeds Giant Panda within the conservation

• research on the species behaviour

• preserve bamboo forests

outline the function of the International Cooperation for Biodiversity Protection (CBD)

• international treaty that was established at the Rio Earth Summit in 1992

• framework for international cooperation on biodiversity conservation in response to the loss of species and habitats worldwide

outline the CBD’s Nagoya Protocol

access to genetic resources + fair and equitable sharing of benefits arising from their use ; particularly important for indigenous + biodiversity rights

identify some of the challenges of the CBD

• lack of enforcement - states are not legally bound to achieve outcomes. implementation is often relied on by national government which may lack resources/political will

• funding gaps - biodiversity rich countries struggle to secure necessary funding to implement their strategies

• progress - hindered by climate change, deforestation etc

distinguish the effectiveness between large vs. small reserves

larger reserves = support more ecosystems, habitats, and species ; benefits large + migratory species (umbrella species)

small reserves = require careful management, need to facilitate movement of migratory species based on migratory patterns

depends on the species - larger species need bigger areas, some species (i.e birds) do better in several smaller reserves

smaller reserves = greater edge effect

describe how the shape of conservation areas can impact its effectiveness

circular conservation areas are usually better as they have less edge effect.

describe edge effect

edge effect are ecological changes at the boundaries of different ecosystems or habitats. (e.g. boundary between protected area / human settlements)

these boundaries are often susceptible to disturbances that can negatively impact the protected area

describe how the location of conservation areas can impact its effectiveness

protected areas are best when situated away from dense human settlements

ideally has three zones (by UNESCO)

1. pristine core area w/ limited human contact unless for research

2. buffer zone - limited human activity, acts as a protective shield for the core

3. transition area - allows for tourism / other human activity

identify the importance of wildlife corridors in conservation areas and some disadvantages

wildlife corridors - areas maintained/established for species movement (e.g. connecting reserve areas together)

• enables species migration

• reduces population isolation

• enhancing gene pools

disadvantages

• increased spread of disease

• invasive species threats

• heightened predation/hunt risk

define rewilding

restoring natural processes in ecosystems by reintroducing key species and minimizing human influence

identify types of rewilding strategies

• reintroduction of apex predators + keystone species

  • regulate prey populations

  • prevention of overgrazing

  • ecosystem balance

  • food web regulation

• habitat connection

  • creating wildlife corridors

  • natural landscape restoration

  • promotes migration for resources + adapt to environment

• stopping agriculture + resource harvesting

  • restoring soil fertility + native plants

  • reestablish natural ecological processes

• ecological management

  • removing invasive species

  • improving biogeochemical cycles

identify some benefits of rewilding

• restores ecosystem balance

• enhances biodiversity

• improves ecosystem services

• promotes climate resilience

• encourages ecotourism = economic

• supports habitat connectivity + migration

explain an example of rewilding and evaluate its benefits

Gorongosa national park in Mozambique had to restore their ecosystem after the Mozambique civil war + increased poaching

• reintroduction of apex + keystone species

• education + employment opportunities for locals

• reforestation

• regenerative agricultural practices

benefits both ecosystem + local communities, increases socioeconomic development

outline some of the potential challenges of conservation and rewilding

• land use - due to large area requirements, can conflict w/ agriculture, urbanization, resource extraction

• climate change - alters ecosystems

• lack of funding + political will

• slow ecological recovery

• high costs

• dependence on tourism

• risk of invasive species/ecological imbalances

outline some key success factors needed for conservation and regeneration

• community support - local involvement ensures projects align with their needs + integrates local knowledge

• adequate funding

• public education + awareness - fosters sustainable practices + community involvement

• appropriate legislation

• scientific research - guides intervention + provides data on species/ecosystems

distinguish between ecocentric and anthropocentric perspectives on conservation

ecocentric

• low intervention, in situ methods

• intrinsic value of biodiversity

• national parks/nature reserves

• low human impact

• preserves natural processes

• slow adaptation to environmental changes

anthropocentric

• scientific intervention, ex situ methods

• societal + economic value of biodiversity

• zoos, gene bank, ecotourism

• generates economic benefits

• supports scientific research

• high resource demand

• over-reliance on tech

explain why it is important to consider environmental justice in conservation approaches

environmental justice ensures fair distribution of conservation benefits + includes marginalised communities in decision making

• must address historical inequities

• prevent further social inequalities

describe the tragedy of the commons

the possible outcomes of the shared, unrestricted use of a resource

• illustrates how individuals acting in their own self-interest can deplete shared resources, leading to long-term negative consequences for community/sustainability/biodiversity

outline the different roles in species conservation

government

• policy + legislation

• resource allocation

• international agreements

businesses

• adopting sustainable practices

• innovation

• raising consumer awareness

• funding conservation projects

• collaboration w/ conservation organizations

NGO

• funding + expertise

• research + monitoring

• advocacy + awareness

individual

• lifestyle choices

• community engagement

• advocacy

explain how Christine Tompkin’s rewildling strategy reflects environmental perspectives/values, as well as other conservation concepts

• brought land areas to transform them into conservation areas and donating them as national parks

• working with local, national, international levels (different roles in conservation)

• reintroduction of keystone species (mixed conservation approach)

  • ex situ - land conservation

  • in situ - reintroduction of species for self-regulating ecosystem services

provide an example of speciation

darwin’s finches - due to the differences of topography and environmental conditions on the island, the beaks of the birds have evolved to adapt to their feeding habits

one species arrived (common ancestor) and diversified to 13 different species, with each adapted to specific food niches. if the resource for those specific food niches became competitive, it would trigger evolution among the beak size of the finches. the finches adapted to their environmental conditions/food sources, reflected by the size of their beaks.

distinct species would only breed with their own species

describe a species whose conservation status has improved by intervention. consider their decline, the impacts of their decline and the successful conservation strategies

bald eagle

• decline due to illegal hunting, habitat destruction, DDT poisoning in food sources

• legislation (bald eagle protection act) on hunting

• nationwide ban on DDT

• reclassified as least concern by the IUCN in 2024

• impacted the food web (overpopulation of lower trophic levels)

• decrease in biodiversity