Topic 3.3

Question 1

Methods for estimating the number of global species

Answer 1

• Based on their characteristics and relationships.
• Researchers sample specific areas or habitats and gather data to estimate species diversity on a global scale.
• DNA analysis helps identify and categorize species, providing insights into their diversity and distribution.

Question 2

Difficulties in estimating the number of global species

Answer 2

• Many species remain undiscovered or poorly studied, making accurate identification and classification difficult.
• Some species may have subtle differences or hidden variations, leading to underestimation or confusion in species counts.
• Limited resources and access to remote areas make it challenging to sample all ecosystems, resulting in incomplete species assessments.

Question 3

What are the threats that come from human activity to species

Answer 3

• Deforestation, urbanization, and conversion of natural habitats for agriculture pose significant threats to species by reducing their available habitats.
• Pollution from industrial activities, agriculture, and improper waste disposal harms species directly or degrades their habitats.
• Unsustainable hunting, fishing, and poaching for trade put pressure on species populations, leading to declines and even extinctions.
• Rising temperatures, changing rainfall patterns, and sea-level rise disrupt ecosystems, impacting species’ survival and distribution.

Question 4

Criteria used by the IUCN Red List for conservation status

Answer 4

• Population size and growth trend.
• Geographic range and distribution.
• Reproductive efficiency and resilience (ability to recover from disturbances).
• Threats and effectiveness of conservation measures.

Question 5

Role of the IUCN Red List

Answer 5

• The IUCN Red List provides an assessment of the conservation status of species worldwide.
  It serves as a crucial tool for identifying species at risk and prioritizing conservation efforts.
• The Red List helps inform policy decisions, guide conservation actions, and raise awareness about the status and importance of biodiversity.

Question 6

Examples of critically endangered species

Answer 6

• Examples of critically endangered species include the Sumatran orangutan and Amur leopard
• Conservation efforts focus on habitat protection, anti-poaching measures, and breeding programs to save these species from extinction.

Question 7

Case histories of extinct species

Answer 7

• Examples of extinct species include the dodo bird, Tasmanian tiger, and passenger pigeon.
• Factors such as habitat loss, overhunting, and the introduction of invasive species led to their extinction.

Question 8

Case histories of species with improved conservation status through human intervention

Answer 8

• Examples include the black-footed ferret, California condor, and southern white rhinoceros.
• Conservation efforts include captive breeding, habitat restoration, and legal protection.

Question 9

Definition of a biological hotspot

Answer 9

• A biological hotspot is a region characterized by exceptionally high levels of species richness and endemism.
• These areas are often under threat and require conservation attention due to their unique biodiversity.

Question 10

Conflict between exploitation, conservation, and sustainable development in tropical biomes

Answer 10

• Exploitation for economic development VS The need for conservation to protect their biodiversity.
• Exploitation activities such as logging, mining, and agriculture can lead to habitat destruction, pollution, and biodiversity loss in tropical biomes.
• Sustainable development aims to find a balance by utilizing natural resources in a responsible manner, both economic growth and environmental well-being.

Question 11

List the levels of the IUCN red list.

Answer 11

• Extinct (EX): No known individuals of the species exist anymore.
• Extinct in the Wild (EW): The species survives only in captivity or through human intervention, with no wild populations remaining.
• Critically Endangered (CR): The species faces an extremely high risk of extinction in the wild.
• Endangered (EN): The species faces a very high risk of extinction in the wild.
• Vulnerable (VU): The species faces a high risk of extinction in the wild.
• Near Threatened (NT): The species is close to qualifying for a threatened category but does not yet meet the criteria.
• Least Concern (LC): The species is not currently at risk of extinction.
• Data Deficient (DD): There is insufficient information available to assess the species’ conservation status.
• Not Evaluated (NE): The species has not yet been evaluated for its conservation status.