Conservation of Biodiversity

Define biodiversity and its three levels:

Biodiversity = variety of life in a given area
Levels:

• Ecosystem diversity: range of different habitats (e.g. coral reef = high; desert = low)

• Species diversity:
  Species richness = number of species
  Species evenness = how evenly individuals are spread across species

• Genetic diversity:
  Variation in alleles within and between species and populations
  Helps survival against environmental change

Explain how biodiversity can be measured:

• Species richness: total number of species

• Species evenness: how balanced the number of individuals is across species

• High diversity needs both richness + evenness

• Stable ecosystems usually have high diversity

Describe how speciation and extinction affect biodiversity:

• Speciation = new species form → increases biodiversity

• Extinction = species disappear → decreases biodiversity

• Biodiversity increases when speciation > extinction

List causes of biodiversity loss:

• Population growth = more land use & pollution

• Overexploitation: hunting, overfishing

• Habitat loss: deforestation, agriculture

• Pollution: microplastics, fertilisers

• Invasive species: grey squirrels, cane toads

• Disease: chytrid fungus kills amphibians

• Climate change: increases disease spread & habitat loss

Define anthropogenic extinction and give examples:

Anthropogenic extinction = extinction caused by human activity
Examples:

• North Island giant moa: hunted to extinction (New Zealand)

• Caribbean monk seal: hunted for oil/meat (Caribbean)

• Choose a 3rd case study yourself, e.g. Passenger pigeon, Golden toad

Explain how ecosystem loss contributes to biodiversity decline:

• Ecosystem = organisms + environment

• Caused by:

  • Deforestation

  • Urbanization

  • Mining

• Dipterocarp forests (Southeast Asia): clear-cutting for palm oil plantations

List types of conservation and examples:

In situ (in natural habitat):

• Protected areas: national parks, reserves (e.g. Kruger Park)

• Rewilding: reintroduce species or let nature recover (e.g. Knepp estate)

• Reclamation: restore damaged land

Ex situ (outside habitat):

• Zoos: captive breeding, research

• Botanic gardens: plant conservation, cloning

• Seed banks: store dried seeds (e.g. Svalbard Vault)

• Tissue banks: frozen sperm/eggs/DNA (for future use or cloning)

What are the roles of IUCN and IPBES in biodiversity?

• IUCN: publishes Red List (threat levels: LC → EX)

• IPBES: collects global data, advises policy, uses citizen scientists

• Both: provide data and action plans for conservation

Describe the EDGE programme and how it selects species:

EDGE = Evolutionarily Distinct and Globally Endangered
Selection based on:

• Evolutionary distinctiveness: few close relatives, unique traits

• Global endangerment: listed on IUCN Red List
  Examples:

• Chinese giant salamander

• Purple frog

• Largetooth sawfish

What are ethical and practical challenges in conservation?

• Limited resources → must prioritize

• Cultural/political barriers (e.g. war zones)

• Some species more useful to ecosystems

• EDGE provides guidance but not final decisions