Extinction

Question 1

globally extinct

Answer 1

extinct in the wild across its range

Question 2

ecologically extinct

Answer 2

persists at such reduced numbers that its effects on the other species in its community are negligible

Question 3

human-induced extinctions - 3 examples (past)

Answer 3

1 megafauna of Australia and North & South America - 74-86% extinction
2 pacific islands (4000-1000yrs before present) - 2000 species of birds extinct
3 European colonisation of the Pacific (since 1778) - Hawaii

Question 4

greatest extinction

Answer 4

permian-triassic extinction
95% of marine life
50% of taxa

Question 5

The cookie-cutter model

Answer 5

• removing habitat from particular areas has greater impact than other habitats
  are there hotspots for extinction?
• areas with higher concentration of endemic species

Question 6

human-induced extinctions - 2 examples (present)

Answer 6

Madagascar ~20% of global extinctions

Singapore ~26% already lost, ~ 76% loss predicted with current habitat loss (time lag)

Question 7

endemism

Answer 7

found naturally in only one place

Question 8

vulnerability to extinction factor - hunting (with example)

Answer 8

Tasmanian Tiger - extinct 1935

hunted sheep

Question 9

vulnerability to extinction factor - narrow geographical range (with example)

Answer 9

Ivory-billed woodpecker [Southeastern United States]

- very small and limited distribution

Question 10

vulnerability to extinction factor - one or only a few populations (with example)

Answer 10

Bannerman’s turaco [Cameroon]
- montane (mountain) forests
lots of lower forest cleared = fragmented habitat

Question 11

vulnerability to extinction factor - small population

Answer 11

vulnerability to demographic & environmental variation, reduced genetic variability and natural disasters

Question 12

vulnerability to extinction factor - animals with a large home range (with example)

Answer 12

Bengal Tiger

- habitat fragmentation -> lower genetic diversity…

Question 13

vulnerability to extinction factor - animals with large bodies (with example)

Answer 13

Pleistocene megafauna extinctions - larger animals hunted first .

Question 14

vulnerability to extinction factor - poor at dispersing (with example)

Answer 14

Door mouse/deer
E.g. roads divide populations
E.g. wildlife corridors not effective as animals may not know where they are/ predator funnel

Question 15

vulnerability to extinction factor - seasonal migrants (with example)

Answer 15

Nightingale

• being caught and eaten on Malta and Cyprus
• many birds do not survive migration

Question 16

vulnerability to extinction factor - specialised niche requirements (with example)

Answer 16

.Large blue butterfly [UK]

- needs lot of Thyme

Question 17

vulnerability to extinction factor - no previous contact with people (with example)

Answer 17

Dodo [Mauritius]
ship rats
no fear of humans

Question 18

vulnerability to extinction factor - close relative that has gone extinct

Answer 18

relative of Dodo

Question 19

vulnerability to extinction factor - requires pristine, undisturbed environments

Answer 19

Freshwater pearl

- last for hundreds on years

Question 20

vulnerability to extinction factor - form aggregation

Answer 20

passenger pigeon (easier to shoot (+hunting))