Chapter 47 - Biodiversity

Question 1

Define Biodiversity

Answer 1

a measurement of the number/abundance of species present in a given area (biosphere, biome, or ecosystem)

Question 2

What are the 3 types of biodiversity?

Answer 2

• Species - number of species and their abundance
• Genetic - genetic variation present in the individuals in a population or species
• Ecosystem - number of different ecosystems in an area

Question 3

Less than ____% of organisms on Earth have been described and named

Answer 3

20%

Question 4

True or False: Biodiversity is evenly distributed on Earth

Answer 4

False: biodiversity is not evenly distributed because of the different biomes and their different abilities to support life

Question 5

Biomes near the equator have ________ biodiversity than biomes in the ________

Answer 5

greater | far north or far south

Question 6

Equatorial biomes…:

Answer 6

• Receive more annual sunlight
• Consistent annual temperatures
• Large annual precipitation
• Have been around longer
• Increased heterogeneity
• High rate of endemism (hotspots of biodiversity)

Question 7

What 2 things determine biodiversity over time?

Answer 7

Speciation & extinction rates
* macroevolutionary birth and death
* increased speciation = more species
* increased extinction = fewer species

Question 8

There have been _____ major extinction events on Earth

Answer 8

5

Question 9

What are the 5 mass extinctions?

Answer 9

• Ordovician-Silurian - 450 mya; caused by glaciation then extreme warming
• Devonian - 375~360 mya; series of small extinction events
• Permian - 251 mya; largest extinction event caused by volcanic eruptions
• Triassic-Jurassic - 205 mya; 85% of species extinct; occured before Pangaea broke
• Cretaceous - 65 mya; caused by volcanic activity and asteroids; mammals became dominant

Question 10

What is the Anthropogenic/Holocene extinction?

Answer 10

• 6th extinction (not mass yet)
• 400 years ago ~ present
• Coincides with expansion of European colonies
• Extinction rate is increasing exponentially
• Dodo bird, Stellar’s sea cow, Passenger pieon, Carolina parakeet, Japanese sea lion, Caribbean monk seal

Question 11

What is the background extinction rate?

Answer 11

one per million species/year

Question 12

What is the current estimated extinction rate?

Answer 12

100E/MSY
By end of century: 1500E/MSY

Question 13

Species-Area relationship estimates species extinction by _______

Answer 13

habitat loss
increased habitat loss → increased species extinct

Question 14

What is DNA barcoding?

Answer 14

sequences area of rapidly evolving genome that we can use to measure biodiversity and input them into a global database

Question 15

What is used for DNA barcoding work in Eukaryotes, Plants, and Fungi?

Answer 15

• Eukaryotes - mitochondrial DNA
• Plants - chloroplast DNA
• Fungi - internal transcribed spacers in RNA

Question 16

What are the 4 different conservation efforts?

Answer 16

• IUCN - global authority on species conservation
• CITES - prevents illegal pet trade
• ESA - protects species that are critically endangered
• MBTA - protects 800 species of birds

Question 17

What are the other 2 ways to conserve biodiversity?

Answer 17

• Preserves - creating wildlife and ecosystem preserves
• Habitat Restoration - restoring dead or damaged ecosystems
• Captive Breeding Programs - animals are transferred between zoos/aquariums to increase genetic diversity