Conservation Biology

Question 1

What is conservation biology?

Answer 1

-Scientific study of the nature and status of earth’s biodiversity with the aim of protecting species, their habitats, and ecosystems from excessive rates of extinction and the erosion of biotic interactions

Question 2

What is extinction?

Answer 2

• Fact of life
• all species become extinct eventually
• species becoming extinct 100-1000 faster than before humans

Question 3

Describe how extinctions have come about through history?

Answer 3

• Humans have caused extinctions
• changing climate has caused extinctions
• Australia had large variety of animals that became extinct when humans arrived (Africa didn’t have equivalent mass extinctions)

Question 4

Why are islands prone to extinction?

Answer 4

• They evolved in the absence of predators
• Humans brought competitors and disease
• Island populations are usually small which increases risk for extinction

Question 5

What are endemic species?

Answer 5

• Species found naturally in only one geographic area and no place else
• usually occupy restricted ranges

Question 6

What are hotspots?

Answer 6

-Areas where species have high endemism

Question 7

How is habitat lost and how does it effect species?

Answer 7

• Land can be cleared for agriculture, housing, and economic development
• losing land is a threat to species

Question 8

Describe values of biodiversity?

Answer 8

• Resources for our survival are found: food, medicine, clothing, energy, shelter
• 40% of prescription/nonprescription drugs have active ingredients extracted from plants

Question 9

What economic value is found in biodiversity?

Answer 9

• Pollination
• Water quality
• Buffers against storms/droughts
• Prevent loss of minerals/nutrients
  ex. tropical rainforest provide more economic benefits than if they were destroyed

Question 10

What are the problems of valuing ecosystems?

Answer 10

• No good estimate of monetary value of services provided by the ecosystem
• People who gain benefits of environmental degradation are often not same people who pay the costs

Question 11

What are some causes of extinction?

Answer 11

• Habitat loss
• Introduced species
• Pollution
• Loss of genetic variation

Question 12

What is habitat fragmentation?

Answer 12

• Dividing the habitat into small, unconnected areas

- Bad because of relationship between range size and extinction rate

Question 13

What is edge effects?

Answer 13

• Changes in microclimate along the edge of a habitat

- The climate on the edge of the habitat is different than the center (in respect to habitat fragmentation)

Question 14

Describe pollution?

Answer 14

• Aquatic environments are particularly vulnerable

- Many lakes are sterilized by acid rain

Question 15

Describe disruption?

Answer 15

ex. people who visit bat caves even as little as four times a month caused a large decline in population size

Question 16

What is exploitation?

Answer 16

• Overkilling of a species

ex. whales overkilled, they take 2-3 years to have children so repopulating themselves takes a long time

Question 17

Describe introduced species?

Answer 17

• Brought by others/not originally there

- Threaten native species and habitats

Question 18

Describe colonization?

Answer 18

• process by which a species expands its geographic range
• humans can transport plants and animals, expanding their range
  ex. zebra mussels

Question 19

Describe how extinction cascade happens?

Answer 19

• Disruption to ecosystem causes extinction cascade

- Human activities that effect one species can effect many other species

Question 20

Describe the difference between weather and climate?

Answer 20

• Weather: short term changes
  ex. temp, air pressure, wind, precipitation
• Climate: average conditions in a particular area over a long period of time
  ex. temp, precipitation (fluctuations normal)

Question 21

Describe the natural greenhouse effect?

Answer 21

• Greenhouse gases absorb heat radiated by the earth

- The gases then emit infrared radiation that warms the atmosphere

Question 22

Why are oceans warming?

Answer 22

• They absorb 1/3 of CO2 from the atmosphere
• The CO2 combines with he water to make carbonic acid
• Acidity threatens corals, snails, shelled animals, phytoplankton

Question 23

What are the effects of a warmer atmosphere?

Answer 23

• Positive feedback loop: accelerated melting of polar ice
• Climate tipping point: melting of summer arctic sea ice , changes in arctic seawater temperatures can influence the jet stream