6: Threats to Biodiversity

Question 1

What does ‘extinct’ mean

Answer 1

Species is extinct when, after a thorough search, no member of the species is found alive anywhere in the world

Question 2

What is extirpated

Answer 2

Species not extinct, but extinct in a specific area/region

Question 3

What is ecologically/functionally extinct

Answer 3

Number of animals so small that they no longer play a significant role in ecosystem function; or the population is no longer viable

Question 4

What is the 6th extinction

Answer 4

Spread of humans causing many species to go extinct due to: hunting, loss of habitat, competition, invasive species

Question 5

What are indirect threats

Answer 5

Agriculture, residential development, industry, energy production, mining, logging, transportation and roads
Leads to direct threats

Question 6

What are direct threats to biodiv

Answer 6

Habitat loss, fragmentation, degradation, overexploitation, invasive species, disease, climate change

Question 7

What is loss of biodiversity

Answer 7

Extinction of species/pops
Degradation of ecosystems
Erosion of genetic diversity

Question 8

Slide 7

Answer 8

Know diagram

Question 9

What is coral bleaching

Answer 9

Water is too warm, corals expel the algae living in their tissues causing coral to turn white
Corals are not dead, can survive bleaching but are under stress and subject to mortality

Question 10

What are some causes of coral reef destruction

Answer 10

Reef trampling
Natural hazards
Tourism
Poor anchoring
Scientific research
Overfishing
Collection of coral
Dynamite fishing

Question 11

What are the main 7 threats to animal populations

Answer 11

1. Exploitation: 37%
2. Habitat degradation and change: 31%
3. Habitat loss: 13%
4. Climate change: 7%
5. invasive species: 5%
6. Pollution: 4%
7. Disease: 2%

Question 12

What are the main threats to birds? Mammals? Fish? Reptiles/amphibians?

Answer 12

Birds = habitat loss/degradation

Mammals = habitat loss/degradation, overexploitation (domestication & hunting)

Fish = overexploitation

Reptiles/amphibians = habitat loss/degradation

Question 13

Reptiles/birds undergo a lot of speciation, meaning?

Answer 13

Group within a species separates and develops unique characteristics
Lots of intraspecies competition

Question 14

The three habitat-related threats

Answer 14

Fragmentation -> degradation -> loss

Question 15

What are the diff types of habitat loss

Answer 15

Aesthetic vs ecological
Permanent vs temporary
Functional (utility gone) vs structural (composition changes)

Question 16

What is the problem with palm oil production?

Answer 16

Major driver of deforestation and degradation of natural habitats in tropical Asia and Central/South America. Put up forests nearly impenetrable to local fauna to grow the palm trees
193 critically endangered species related to palm oil production

Question 17

What is habitat fragmentation

Answer 17

Creates edges, barriers, conduits in habitats
Limits dispersal and alters movement of individuals
Sub-divides, isolates or intersects populations

Question 18

Stages of loss/fragmentation

Answer 18

Dissection -> perforations -> fragmentation -> attrition (erosion)

Question 19

What is the usual cause of habitat degradation?

Answer 19

Pollution
- chemical (to air, water, soil)
- light, noise, electromagnetic

Question 20

Four causes of habitat degradation

Answer 20

Pollution, conversion, climate change, anthropogenic disease

Question 21

What are microplastics? Where do they come from?

Answer 21

Extreme pollution problem
1um-5mm diameter

Personal care products, plastic manufacture/degradation, polyester clothing